Cfr-mediated linezolid-resistance among methicillin-resistant coagulase-negative staphylococci from infections of humans.

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Cui, Lanqing; Wang, Yang; Li, Yun; He, Tao; Schwarz, Stefan; Ding, Yujing; Shen, Jianzhong; Lv, Yuan

2013-01-01

Four methicillin-resistant coagulase-negative staphylococci (MRCoNS), one Staphylococcus haemolyticus and three Staphylococcus cohnii, from infections of humans collected via the Ministry of Health National Antimicrobial Resistance Surveillance Net (Mohnarin) program in China were identified as linezolid-resistant. These four isolates were negative for the 23S rRNA mutations, but positive for the gene cfr. Mutations in the gene for the ribosomal protein L3, which resulted in the amino acid exchanges Gly152Asp and Tyr158Phe, were identified in S. haemolyticus 09D279 and S. cohnii NDM113, respectively. In each isolate, the cfr gene was located on a plasmid of ca. 35.4 kb, as shown by S1 nuclease pulsed-field gel electrophoresis and Southern blotting experiments. This plasmid was indistinguishable from the previously described plasmid pSS-02 by its size, restriction pattern, and a sequenced 14-kb cfr-carrying segment. Plasmid pSS-02 was originally identified in staphylococci isolated from pigs. This is the first time that a cfr-carrying plasmid has been detected in MRCoNS obtained from intensive care patients in China. Based on the similarities to the cfr-carrying plasmid pSS-02 from porcine coagulase-negative staphylococci, a transmission of this cfr-carrying plasmid between staphylococci from pigs and humans appears to be likely.

CRISPR-Cas Systems Features and the Gene-Reservoir Role of Coagulase-Negative Staphylococci

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Ciro C. Rossi

2017-08-01

Full Text Available The claimed role of gene reservoir of coagulase-negative staphylococci (CoNS could be contradicted by estimates that CRISPR/Cas systems are found in the genomes of 40–50% of bacteria, as these systems interfere with plasmid uptake in staphylococci. To further correlate this role with presence of CRISPR, we analyzed, by computational methods, 122 genomes from 15 species of CoNS. Only 15% of them harbored CRISPR/Cas systems, and this proportion was much lower for S. epidermidis and S. haemolyticus, the CoNS most frequently associated with opportunistic infections in humans. These systems are of type II or III, and at least two of them are located within SCCmec, a mobile genetic element of Staphylococcus bacterial species. An analysis of the spacers of these CRISPRs, which come from exogenous origin, allowed us to track the transference of the SCCmec, which was exchanged between different strains, species and hosts. Some of the spacers are derived from plasmids described in Staphylococcus species that are different from those in which the CRISPR are found, evidencing the attempt (and failure of plasmid transference between them. Based on the polymorphisms of the cas1 gene in CRISPRs of types II and III, we developed a multiplex polymerase chain reaction (PCR suitable to screen and type CRISPR systems in CoNS. The PCR was tested in 59 S. haemolyticus strains, of which only two contained a type III cas1. This gene was shown to be expressed in the exponential growth, stationary phase and during biofilm formation. The low abundance of CRISPRs in CoNS is in accordance with their role as gene reservoirs, but when present, their spacers sequence evidence and give an insight on the dynamics of horizontal genetic transfer among staphylococci.

Coagulase-negative Staphylococci in Danish blood cultures: species distribution and antibiotic susceptibility.

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Jarløv, J O; Højbjerg, T; Busch-Sørensen, C; Scheibel, J; Møller, J K; Kolmos, H J; Wandall, D A

1996-03-01

The distribution and antibiotic susceptibility of coagulase-negative staphylococci (CoNS) isolated from blood cultures was examined in samples from hospitals covering most of Denmark. A total of 499 CoNS isolates were detected in 477 blood cultures from 340 patients and speciated as Staphylococcus epidermidis, 285; Staphylococcus hominis, 61; Staphylococcus haemolyticus, 43; Staphylococcus warneri, 12; Staphylococcus cohnii, 7; Staphylococcus saprophyticus, 4; Staphylococcus capitis, 2 and Staphylococcus lugdunensis, 1. Seventy-eight isolates could not be identified to species level and six were Micrococcus spp. In 108 (22.6%) blood culture sets, more than one CoNS strain were found, as detected by species identification, antibiogram and biotyping. Significantly more blood cultures from patients in university hospitals were drawn from central venous catheters. Comparing university and non-university hospitals, the overall antibiotic susceptibility among CoNS was only slightly different, except for methicillin and amikacin. The prevalence of methicillin-resistant strains was 35.1% in the university hospital strains vs. 25.3% in the non-university hospital strains. The overall prevalence of methicillin resistance was 32%. Great geographic variation in both species distribution and antibiotic resistance was observed. The high prevalence of S. epidermidis makes subtyping of this species important.

Isolation of coagulase-negative staphylococci from extended-wear soft contact lenses in asymptomatic patients.

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Faghri, Jamshid

2008-05-01

Coagulase-negative staphylococci and diphtheroids are normal inhabitants of the outer surface of the human eye. These microorganisms serve as part of the defense mechanism of the ocular anatomy in preventing colonization and infection by pathogenic bacteria. Nevertheless, infections associated with contaminated solutions and cases became serious problems for people who wear soft contact lenses. The aim of this study is to isolate and identify aerobic bacteria, particularly, gram-negative species associated with the use of extended-wear soft contact lenses. Extended-wear contact lenses were collected, using aseptic technique, from the eyes of individuals after 30 days of extended wear (5-7 day intermittent periods) and were examined for adhered aerobic bacteria. Coagulase-negative staphylococci were isolated from 74% of the lenses. Serratia marcescens was found at an incidence of 10% and Pseudomonas aeruginosa at an incidence of 6%. The presence of species of bacteria, including P. aeruginosa and S. marcescens, which have been associated with daily wear soft contact lenses, solutions, and cases also seem to be associated with extended-wear lenses.

Challenges in the Prevention of Coagulase-Negative Staphylococcal Sepsis in Neonates

NARCIS (Netherlands)

V. Hira (Vishal)

2013-01-01

textabstractCoagulase-negative staphylococci (CoNS) are the leading cause of late-onset sepsis (LOS) worldwide. As antibiotic resistance is dramatically increasing in these organisms, prevention is becoming more and more important. CoNS that are isolated from blood cultures of neonates with LOS on

Study of antibiotic resistance of staph aureus and coagulase negative staphylococci isolated from patient samples

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M Anvary

2006-04-01

Full Text Available Introduction: Drug resistant Staphylococci are the most important agents of nosocomial infections. In this survey, effect of different antibiotics on these bacteria and their drug resistance was investigated. Methods: The study included 500 strains of Staphylococci. Minimum Inhibitory Concentrations of all antibiotics was determined by the broth macro dilution technique and standard methods from the National Committee for Clinical Laboratory Standards. Result : Oxacillin resistance of S. aureus was 14.2% and that of coagulase-negative staphylococci was 53.4%. The activity of different antibiotics is presented in detail. Conclusion: Surveillance of strains resistant to methicillin is necessary.

Fluoroquinolone susceptibilities to methicillin-resistant and susceptible coagulase-negative Staphylococcus isolated from eye infection Suscetibilidade dos Staphylococcus coagulase negativo meticilina-resistentes e suscetíveis isolados em infecções oculares

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Adália Dias Dourado Oliveira

2007-03-01

Full Text Available PURPOSE: To evaluate the fluoroquinolone susceptibilities of ocular isolate coagulase-negative staphylococci (CoNS, identified at the Microbiology Laboratory - UNIFESP. DESIGN: Experimental laboratory investigation. METHODS: The minimum inhibitory concentrations (MICs of 21 strains of methicillin-resistant coagulase-negative staphylococci (MRCoNS and 22 methicillin-sensitive coagulase-negative staphylococci (MSCoNS to ciprofloxacin, ofloxacin, gatifloxacin and moxifloxacin were determined, using the E-test method standardized by the Clinical and Laboratory Standards Institute (CLSI/NCCLS. RESULTS: The MIC90s (µg/ml for the second generation of tested fluoroquinolones were higher than the fourth generation, especially for the methicillin-resistant coagulase-negative staphylococci group. CONCLUSION: Our results indicate that methicillin-sensitive coagulase-negative staphylococci are more susceptible to quinolones than are methicillin-resistant coagulase-negative staphylococci and that fourth generation fluoroquinolones appear to be more potent, affecting even coagulase-negative staphylococcal strains resistant to second generation fluoroquinolones.OBJETIVOS: Avaliar a suscetibilidade a fluorquinolonas dos Staphylococcus coagulase-negativo (SCoN identificados no Laboratório de Microbiologia Ocular da Unifesp. MÉTODOS: Foi determinada a concentração inibitória mínima de 21 cepas de SCoN meticilina-resistentes e 22 meticilina-sensíveis para ciprofloxacina, ofloxacina, gatifloxacina e moxifloxacina, utilizando o E-test estandartizado pelo CLSI/NCCLS. RESULTADOS: Os MIC90 (µg/ml de 43 SCoN isolados para fluorquinolonas de segunda geração foram maiores do que os de quarta geração, principalmente para o grupo dos meticilina-resistentes. CONCLUSÃO: Nossos resultados indicam que Staphylococcus coagulase-negativo meticilina-sensíveis são mais suscetíveis às quinolonas do que os Staphylococcus coagulase-negativo meticilina

Clinical and molecular features of methicillin-resistant,coagulase-negative staphylococci of pets and horses

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Kern, Andrea; Perreten, Vincent

2017-01-01

Objectives To determine the antibiotic resistance and fingerprint profiles of methicillin-resistant coagulase-negative staphylococci (MRCoNS) from animal infections among different practices and examine the history of antibiotic treatment. Methods Isolates were identified by mass spectrometry and tested for antimicrobial resistance by broth dilution, microarrays and sequence analysis of the topoisomerases. Diversity was assessed by PFGE, icaA PCR and staphylococcal cassette chromosome mec (SC...

Speciation and antibiotic susceptibility patterns of coagulase-negative staphylococci.

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Smith, D J; Kaplan, R L; Landau, W; Trenholme, G M

1982-08-01

During a six month period, 191 isolates of coagulase-negative staphylococci from blood, urine, cerebrospinal fluid and heart valves were identified to species level and tested for antimicrobial susceptibility. Seventy-one percent of isolates were Staphylococcus epidermidis, 8% Staphylococcus warneri, 7% Staphylococcus hominis, 7% Staphylococcus haemolyticus, 4% Staphylococcus capitis, 2% Staphylococcus saprophyticus and 1% Staphylococcus cohnii. Approximately 4% of isolates were felt to be associated with infection. Overall, 18% of isolates were susceptible to penicillin G, 61% oxacillin, 98% cephalothin, 98% cefamandole, 72% cefotaxime, 95% cefsulodin, 76% gentamicin, 64% clindamycin and 98% rifampicin. All isolates were susceptible to vancomycin. Vancomycin, rifampicin, cephalothin and cefamandole showed excellent activity against oxacillin-resistant isolates. With one exception, speciation was not helpful in determining whether or not an isolate was associated with infection.

Finding of coagulase negative staphylococci in the herd with an increased number of somatic cells in milk and their antimicrobial susceptibility

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Katić Vera

2013-01-01

Full Text Available Coagulase-negative staphylococci (CNS are generally considered to be opportunistic pathogens. Controlling CNS mastitis is difficult because the epidemiology is not clear, and the CNS group consists of about 40 different Staphylococcus species. Therefore, the aim of this study was to determine the prevalence of coagulasenegative staphylococci in milk of the cows with subclinical mastitis, as well as to determine different CNS species isolated from quarter milk samples for their susceptibility to antimicrobials used commonly for mastitis therapy. On the farm where there was found an increase of somatic cells in bulk milk, 112 dairy cows were examined by mastitis test. From 52 udder quarters where mastitis test showed an increase of somatic cells, milk samples were taken for bacteriological examination. For isolating the causes of mastitis there was used blood agar. Identification of the causative agents of mastitis was carried out on the basis of colony appearance on blood agar and their physiological characteristics. Coagulasepositive staphylococci sensitivity which cause mastitis was tested by Kirby Bauer method. For susceptibility testing there were used commercially produced discs containing: 10 IU penicillin, amoxicillin/clavulanic acid (20 +10 μg, cloxacillin 25 μg, 30 μg amoxicillin, cephalexin 30 μg, ceftiofur 30 μg, 15 μg lincomycin, gentamicin and tetracycline 30 μg. The sensitivity of microorganisms was evaluated on the basis of inhibition zone diameter recommended by the manufacturer and was labeled as sensitive (S moderately sensitive (I or resistant (R. Coagulase-negative staphylococci were isolated from 61.53% of samples from cows with subclinical mastitis, making them the most common cause of subclinical mastitis. The highest resistance of coagulase-negative staphylococci was found to penicillin G (58.33% of isolates. Full sensitivity of coagulase-negative staphylococci was found to amoxicillin / clavulanic acid (100% of

Distribution of coagulase-positive staphylococci in humans and dogs

OpenAIRE

Jurate Sleiniute; Jurate Siugzdaite

2015-01-01

Staphylococci form part of the normal flora of humans and a wide variety of animals. Some staphylococcal species also cause infections for human and household pets. The aim of this study was to investigate the prevalence of coagulase-positive staphylococci in humans and dogs within a common household. Coagulase-positive staphylococci could not be identified phenotypically in all cases. Molecular methods were used for the correct identification of pathogenic staphylococci. The prevalence of St...

Automated systems in the identification and determination of methicillin resistance among coagulase negative staphylococci

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Juliana Caierão

2006-05-01

Full Text Available Coagulase-negative staphylococci (CoNS are an important cause of nosocomial bacteremia, specially in patients with indwelling devices or those submitted to invasive medical procedures. The identification of species and the accurate and rapid detection of methicillin resistance are directly dependent on the quality of the identification and susceptibility tests used, either manual or automated. The objective of this study was to evaluate the accuracy of two automated systems MicroScan and Vitek - in the identification of CoNS species and determination of susceptibility to methicillin, considering as gold standard the biochemical tests and the characterization of the mecA gene by polymerase chain reaction, respectively. MicroScan presented better results in the identification of CoNS species (accuracy of 96.8 vs 78.8%, respectively; isolates from the following species had no precise identification: Staphylococcus haemolyticus, S. simulans, and S. capitis. Both systems were similar in the characterization of methicillin resistance. The higher discrepancies for gene mec detection were observed among species other than S. epidermidis (S. hominis, S. saprophyticus, S. sciuri, S. haemolyticus, S. warneri, S. cohnii, and those with borderline MICs.

Emergence of linezolid-resistant coagulase-negative staphylococci in an intensive care unit.

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Balandin, Bárbara; Lobo, Beatriz; Orden, Beatriz; Román, Federico; García, Elena; Martínez, Rocío; Valdivia, Miguel; Ortega, Alfonso; Fernández, Inmaculada; Galdos, Pedro

2016-01-01

The aim of this study was to report the emergence of linezolid-resistant coagulase-negative staphylococci (CoNS) in an intensive care unit. An observational study was conducted in critically ill patients with colonization or infection by linezolid-resistant CoNS between January 2010 and December 2014. We analyzed the epidemiological and clinical features, and the mechanism of resistance to linezolid. We also evaluated the association between the incidence of linezolid-resistant CoNS strains and the consumption of linezolid in the study period. During the study period 49 patients had a linezolid-resistant CoNS strain isolated from clinical samples (blood in 42 cases, urine in 6, peritoneal fluid in 1). Molecular study showed a combination of mechanisms of resistance. Most patients were critically ill (APACHE II score = 21.9 ± 8.3) and nearly all had undergone surgery and invasive procedures, and had prior exposure to antibiotics. Linezolid-resistant CoNS were considered to be contaminants in 42 patients and associated with infection in 7 patients, comprising bacteremia and septic shock in most of them. They were successfully treated with glycopeptides or daptomycin. A modest significant correlation was observed between the decrease in linezolid consumption and the lower incidence of resistant isolates. Linezolid-resistant CoNS had emerged in critically ill patients with severe underlying diseases and prior antibiotic exposure. Most isolates represented colonization; however, linezolid-resistant CoNS can produce serious infections in critically ill patients. Glycopeptides and daptomycin seem to provide useful alternatives for therapy of these infections. A relationship was found between linezolid consumption and the incidence of linezolid-resistant CoNS strains.

Methicillin-resistant coagulase-negative staphylococci from healthy dogs in Nsukka, Nigeria

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Kennedy F. Chah

2014-01-01

Full Text Available The occurrence, resistance phenotype and molecular mechanisms of resistance of methicillin-resistant staphylococci from groin swabs of 109 clinically healthy dogs in Nsukka, Nigeria were investigated. The groin swab samples were cultured on mannitol salt agar supplemented with 10 µgof cloxacillin. Sixteen methicillin-resistant coagulase negative staphylococci (MRCoNS, all harbouring the mecA gene were isolated from 14 (12.8% of the 109 dogs studied. The MRCoNS isolated were: S. sciuri subspecies rodentium, S. lentus, S. haemolyticus, and S. simulans with S. sciuri subspecies rodentium (62.5% being the predominant species. Thirteen (81.3% of the MRCoNS were resistant to tetracycline while 12 (75% and 10 (62.5% were resistant to kanamycin and trimthoprim-sulphamethoxazole respectively. None of the isolates was resistant to fusidic acid, linezolid and vancomycin. Thirteen (81.3% of the MRCoNS were multi-drug resistance (MDR. Other antimicrobial genes detected were: blaZ, tet(K, tet(M, tet(L, erm(B, lnu(A, aacA-aphD, aphA3, str, dfr(G, cat pC221,and cat pC223. Methicillin-resistant staphylococci are common colonizers of healthy dogs in Nigeria with a major species detected being S. sciuri subsp. rodentium.

Identification of coagulase-negative staphylococci with the API staph system.

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Gemmell, C G; Dawson, J E

1982-11-01

A kit for the identification of staphylococci based on the biochemical criteria proposed by Kloos and Schleifer (W.E. Kloos and K.H. Schleifer, J. Clin. Microbiol., 1:82-88, 1975) is now available commercially. The system was used to identify 100 strains of coagulase-negative staphylococci isolated from various body sites as the primary etiological agent of clinical infection. The increasing importance of staphylococci and their resistance to antibiotics provided the rationale for such an investigation. Over 90% of the Staphylococcus isolates were easily identified as to their species on the basis of their reaction profile to 19 biochemical tests included in the kit. The remainder, which showed minor variations, could also be assigned to the various species. Identification of the isolates was as follows: S. epidermidis, 54; S. haemolyticus, 5; S. simulans, 2; S. hominis, 1; S. capitis, 4; S. cohnii, 2; S. warneri, 2; S. xylosus, 8; and S. saprophyticus, 22. Antibiotic sensitivity patterns were determined for each of the isolates. Novobiocin resistance was detected in strains of S. saprophyticus and S. xylosus, a property hitherto recognized in Micrococcus sp. type 3 causing bacteriuria in young women. Resistance to penicillin was widespread among strains of several species, whereas resistance to tetracycline was mainly confined to strains of S. epidermidis. General resistance to sulfamethoxazole and nalidixic acid was found among all strains, with almost uniform sensitivity to the other drugs tested.

High prevalence of methicillin-resistant coagulase-negative staphylococci isolated from a university environment in Thailand.

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Seng, Rathanin; Leungtongkam, Udomluk; Thummeepak, Rapee; Chatdumrong, Wassana; Sitthisak, Sutthirat

2017-06-01

The present study was conducted to isolate and characterize the molecular epidemiology of the methicillin-resistant staphylococci in the general university environment, where all five locations; the library, restrooms, canteens, computer rooms and outdoor surfaces, are in common use by a large population of students. We used Mannitol Salt Agar (MSA) supplemented with 4 μg/ml of oxacillin to screen the methicillin-resistant staphylococci. The species level was identified by PCR of rdr (Staphylococcus epidermidis), groESL (Staphylococcus haemolyticus) and nuc (Staphylococcus aureus and Staphylococcus warneri) genes and DNA sequencing of tuf and dnaJ genes. The susceptibility patterns of the isolates were determined using the disk diffusion method. Antibiotic and disinfectant resistance genes, together with SCCmec types, were detected by the PCR method. The methicillin resistant-staphylococci were isolated from 41 of 200 samples (20.5%), and all of them were found to be methicillin-resistant coagulase negative staphylococci (MR-CoNS). The library had the highest percentage of contamination, with 43.3% of the samples found to be contaminated. All isolates belonged to 6 different species including S. haemolyticus, S. epidermidis, S. warneri, S. cohnii, S. saprophyticus and S. hominis. The antimicrobial resistance rates were highest against penicillin (100%), then cefoxitin (73.1%), erythromycin (73.1%) and oxacillin (68.3%). Altogether, the isolates were approximately 61.0% multidrug resistant (MDR), with the S. epidermidis isolates being the most multidrug resistant. The prevalence of the qacA/B gene was detected in 63.4% of the isolates, and SCCmec could be typed in 43.9% (18/41) of the isolates. The type range was: II (n = 1), IVd (n = 1), I (n = 2), V (n = 6), IVa (n = 8) and untypeable (n = 23). This result indicates that these university environments are contaminated with methicillin-resistant coagulase negative staphylococci that carry various SCCmec types and

Adherence of coagulase-negative staphylococci to plastic tissue culture plates: a quantitative model for the adherence of staphylococci to medical devices.

OpenAIRE

Christensen, G D; Simpson, W A; Younger, J J; Baddour, L M; Barrett, F F; Melton, D M; Beachey, E H

1985-01-01

The adherence of coagulase-negative staphylococci to smooth surfaces was assayed by measuring the optical densities of stained bacterial films adherent to the floors of plastic tissue culture plates. The optical densities correlated with the weight of the adherent bacterial film (r = 0.906; P less than 0.01). The measurements also agreed with visual assessments of bacterial adherence to culture tubes, microtiter plates, and tissue culture plates. Selected clinical strains were passed through ...

Detecção do gene mecA em estafilococos coagulase negativa resistentes à oxacilina isolados da saliva de profissionais da enfermagem Detection of mecA gene in oxacillin-resistant coagulase-negative staphylococci isolated from the saliva of nursing professionals

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Juliana de Oliveira Rosa

2009-08-01

Full Text Available Estafilococos coagulase negativa estão frequentemente associados às infecções nosocomiais e os profissionais da saúde podem ser reservatório e dissemina-los no hospital e comunidade. O objetivo desse estudo foi identificar espécies de estafilococos coagulase negativa isolados da saliva de profissionais da enfermagem, determinar o perfil de resistência e detectar o gene mecA. Foram selecionados 100 estafilococos coagulase negativa, sendo 41 identificados como Staphylococcus epidermidis, 25 Staphylococcus saprophyticus, 18 Staphylococcus haemolyticus, 8 Staphylococcus cohnii, 4 Staphylococcus lugdunenses, 3 Staphylococcus capitis, e 1 Staphylococcus Simulans. Desses, 32% apresentaram resistência à oxacilina, 84,4% à mupirocina, 32% à cefoxitina, e todos sensíveis a vancomicina. Dos estafilococos coagulase negativa resistentes à oxacilina, 93,7% desenvolveram-se no agar oxacilina (6µg/ml e o gene mecA foi detectado em 75%. Os resultados sinalizam que maiores investimentos devem ser direcionados a identificação das espécies de estafilococos coagulase negativa nas instituições de saúde e na comunidade.Coagulase-negative staphylococci are frequently associated with nosocomial infections, and healthcare professionals can be reservoirs and spread them in hospitals and in the community. The aim of this study was to identify species of coagulase-negative staphylococci isolated from the saliva of nursing professionals, determine the resistance profile and detect the mecA gene. One hundred coagulase-negative staphylococci were selected: 41 were identified as Staphylococcus epidermidis, 25 as Staphylococcus saprophyticus, 18 as Staphylococcus haemolyticus, eight as Staphylococcus cohnii, four as Staphylococcus lugdunenses, three as Staphylococcus capitis and one as Staphylococcus simulans. Of these, 32% presented oxacillin resistance, 84.4% mupirocin resistance and 32% cefoxitin resistance, and all were vancomycin sensitive. Among the

Factors associated with methicillin-resistant coagulase-negative staphylococci as causing organisms in deep sternal wound infections after cardiac surgery

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R. Sommerstein

2015-07-01

Full Text Available Established preoperative antibiotic prophylaxis in cardiac surgery is ineffective against methicillin-resistant coagulase-negative staphylococci (CoNS. This case–control study aimed to determine factors predicting deep sternal wound infections due to methicillin-resistant CoNS. All cardiac surgery patients undergoing sternotomy between June 2009 and March 2013 prospectively documented in a Swiss tertiary care center were included. Among 1999 patients, 82 (4.1% developed deep sternal wound infection. CoNS were causal in 36 (44% patients, with 25/36 (69% being methicillin resistant. Early reintervention for noninfectious causes (odds ratio (OR 4.3; 95% confidence interval (CI 1.9–9.5 was associated with methicillin-resistant CoNS deep sternal wound infection. Among CoNS deep sternal wound infection, perioperative antimicrobial therapy (p 0.002, early reintervention for noninfectious causes (OR 7.9; 95% CI 0.9–71.1 and time between surgery and diagnosis of infection over 21 days (OR 10.8; 95% CI 1.2–97.8 were associated with methicillin resistance. These findings may help to better tailor preoperative antimicrobial prophylaxis.

Comparative antibiogram of coagulase-negative Staphylococci (CNS) associated with subclinical and clinical mastitis in dairy cows

OpenAIRE

B. K. Bansal; D. K. Gupta; T. A. Shafi; S. Sharma

2015-01-01

Aim: The present study was planned to determine the in vitro antibiotic susceptibility of coagulase-negative Staphylococci (CNS) strains isolated from clinical and subclinical cases of mastitis in dairy cows. Antibiotic sensitivity profile will be helpful to recommend early therapy at the field level prior to availability of CST results. Materials and Methods: The milk samples from cases of clinical mastitis received in Mastitis Laboratory, Guru Angad Dev Veterinary and Animal Sciences Univer...

Susceptibility of coagulase positive staphylococci isolated from cow's mammary gland to antibacterial drugs

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Savić-Rajić Nataša

2009-01-01

Full Text Available Coagulase positive staphylococci are one of the most common causes of chronic udder infection. Indiscriminate use of antimicrobial drugs and their presence in the environment where animals live has led to coagulase positive staphylococci strains resistant to antimicrobial means. Proper and timely treatment of sub-clinical mastitis, based on the most effective use of antimicrobial drugs, is the key to good health of the milk herd. The aim was to determine the antimicrobial efficacy of selected assets in relation to coagulase positive staphylococci isolated from samples of milk taken from individual udder quarters of cows in cases of udder infection from three farms with different mastitis prevalence. From a total of 9245 samples of milk taken from individual udder quarters of cows from three farms, 852 strains isolated were coagulase positive staphylococci. Coagulase positive staphylococci were isolated on blood agar and identified on the basis of macro-morphological characteristics and the coagulase and catalase test. The sensitivity of the coagulase positive staphylococci was tested by the Kirby Bauer agar diffusion method with the following antimicrobials: penicillin 6µg, amoxicillin / sulbactam (20 +10µg, cloxacillin 25 µg, cefalexin 30 µg, ceftiofur 30µg, linkomycin 15µg, 30 µg gentamycin and tetracycline 30 µg. Sensitivity testing of coagulase positive staphylococci, isolated in cases of intramammary cow infections, established a high degree of sensitivity in vitro towards penicilinasa resistant drugs (amoxicillin-sublactam, cloxacilin, cephalosporins of the first and third generations and linkomycin. The highest levels of resistance to penicillin (70.4% were found on a farm with a moderate prevalence of udder infection, then on the farm with the highest prevalence of intramammary infections (60.2% and the lowest on the farm with controlled levels of resistance of infection (43.7%. .

Species Identification And Antibiotic Susceptibilities Of Coagulase- Negative Staphylococci Isolated From Urinary Tract Infection Specimens

International Nuclear Information System (INIS)

Hashmi, A.; Abdullah, F. E.

2016-01-01

Objective: To determine the incidence of Coagulase- negative S. aureusin urinary tract infections and sensitivities of these isolates to antimicrobial agents. Study Design: Cohort study. Place and Duration of Study: Dr. Essa Laboratory and Immunology and Infectious Disease Research Laboratory (IIDRL), Microbiology Department, University of Karachi, from January 2009 to January 2010. Methodology: Urine specimens, suggestive of urinary tract infection (UTI), were identified. Speciation of isolates was done using API-20 Staph.system. Screening of extracellular products was done using SDS-PAGE electrophoresis and Hemolysin on blood-agar plates. Minimum inhibitory concentration (MICs) of antibiotics was estimated by microtiter well plate method. Frequency and percentages were determined and chi-square test was used for comparing proportions with significance at p < 0.05. Results: Coagulase - negative S. aureus(CONS) were the cause of urinary tract infection in 56 out of 1866 outpatient (3 percent) and 164 of 1261 in patient (13 percent), urinary tract infections (p < 0.001). Two hundred and twenty CONS isolates were identified. The most common CONS identified was S. saprophyticus (31 percent, 68 strains). The relative frequency of Coagulase - negative S. aureus was 6 percent (13 strains). All isolates were sensitive to Vancomycin and Linezolid. Resistance was 69 percent to Ampicillin, 53 percent to Methicillin, and 37.5 percent to Ciprofloxacin. Conclusion: CONS are a potential uropathogens, with capability of slime production and resistance to common empirical prescriptions. This also warrants formulation of an appropriate antibiotic policy that covers CONS. (author)

[Left-sided native valve endocarditis by coagulase-negative staphylococci: an emerging disease].

Science.gov (United States)

Haro, Juan Luis; Lomas, José M; Plata, Antonio; Ruiz, Josefa; Gálvez, Juan; de la Torre, Javier; Hidalgo-Tenorio, Carmen; Reguera, José M; Márquez, Manuel; Martínez-Marcos, Francisco; de Alarcón, Arístides

2008-05-01

To describe the epidemiological, clinical, and prognostic characteristics of patients with left-sided native valve endocarditis (LNVE) caused by coagulase-negative staphylococci (CoNS). Prospective multicenter study of endocarditis cases reported in the Andalusian Cohort for the Study of Cardiovascular Infections between 1984 and 2005. Among 470 cases of LNVE, 39 (8.3%) were caused by CoNS, a number indicating a 30% increase in the incidence of this infection over the last decade. The mean age of affected patients was 58.32 +/- 15 years and 27 (69.2%) were men. Twenty-one patients (53.8%) had previous known valve disease and half the episodes were considered nosocomial (90% of them from vascular procedures). Median time interval from the onset of symptoms to diagnosis was 14 days (range: 1-120). Renal failure (21 cases, 53.8%), intracardiac damage (11 cases, 28.2%), and central nervous system involvement (10 cases, 25.6%) were the most frequent complications. There were only 3 cases (7.7%) of septic shock. Surgery was performed in 18 patients (46.2%). Nine patients (23.1%) died, overall. Factors associated with higher mortality in the univariate analysis were acute renal failure (P = 0.023), left-sided ventricular failure (P = 0.047), and time prior to diagnosis less than 21 days (P = 0.018). As compared to LNVE due to other microorganisms, the patients were older (P = 0.018), had experienced previous nosocomial manipulation as the source of bacteremia (P < 0.001), and developed acute renal failure more frequently (P = 0.001). Mortality of LNVE due to CoNS was lower than mortality in Staphylococcus aureus infection, but higher than in Streptococcus viridans infection. Left-sided native valve endocarditis due to CoNS is now increasing because of the ageing of the population. This implies more frequent invasive procedures (mainly vascular) as a consequence of the concomitant disease. Nonetheless, the mortality associated with LNVE due to CoNS does not seem to be

Poor value of surveillance cultures for prediction of septicaemia caused by coagulase-negative staphylococci in patients undergoing haemodialysis with central venous catheters

DEFF Research Database (Denmark)

Nielsen, J; Kolmos, H J; Rosdahl, V T

1998-01-01

Surveillance cultures for the demonstration of coagulase-negative staphylococci in patients on catheter haemodialysis were performed in an attempt to predict dialysis catheter-related septicaemia. In all, 43 patients with 67 haemodialysis catheters were followed for a 1-y period. Once a week, swab...

The relationship between the use of flucloxacillin, vancomycin, aminoglycosides and ciprofloxacin and the susceptibility patterns of coagulase-negative staphylococci recovered from blood cultures.

NARCIS (Netherlands)

Mulder, JG; Kosterink, JGW; Degener, JE

1997-01-01

Antibiotic use is a cause of selection of multiresistant bacterial strains. Over three years (1990-1992) we studied the relation between the use of flucloxacillin, vancomycin, aminoglycosides and ciprofloxacin and the susceptibility of coagulase-negative staphylococci (CNS) recovered from blood

Prevalence of coagulase-negative staphylococci and determination of antimicrobial resistance in accompany with types of SCCmec in isolated of nosocomial infections

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Mohammad Reza Arabestani

2016-03-01

Full Text Available Background: Coagulase-negative staphylococci (CoNS were considered as contaminats previously, but, during the past decade considered as one of the most common photogenic bacteria in hospital. Resistance to beta-lactams especially methicillin in staphylococcus species is being worrying in hospitals. Rapid identification of mechanisms of resistance and confirmation of their resistance to methicillin is a basic principle for antibiotic treatment. The aim of this study was to determine antibiotic resistance, frequency of mecA gene, and determination of SCCmec types in CoNS isolates from teaching hospitals in Iran. Methods: The descriptive cross-sectional study was carried out one hundred clinical samples isolated from patients with an average age of 7-69 years at teaching hospitals in Hamadan City, Iran, from September 2014 to February 2015. After confirmation of isolates by microbiological standard biochemical tests, antimicrobial susceptibility testing was performed by disk agar diffusion (DAD method. After extraction of isolated genomicm, mecA gene was detected. Then, the types of SCCmec were performed by PCR. Results: In this study, 387 clinical samples were collected which among 100 CoNS isolated, Staphylococcus epidermidis was the most prevalent species with frequency 55 (55%, followed by S. haemolyticus 40(40% and S. saprophyticus 5(5%. The highest antibiotic susceptibility was to rifampin 96(96% and the lowest resistance was detected for trimethoprim/sulfamethoxazole (TMP/SMX 47(47%. None of the strains were resistant to vancomycin. Resistance to methicillin was detected in 50% of CoNS isolates. Typing of SCCmec was performed by The polymerase chain reaction (PCR. Frequency types of SCCmec was type III with frequency 13(13%, type V 11(11%, type II 6(6%, type IV 4 (4%, type I 3(3% respectively. Thirteen isolated was not typable in this study. Conclusion: The result of this study showed that a large percentage of coagulase-negative

Linezolid-resistant clinical isolates of meticillin-resistant coagulase-negative staphylococci and Enterococcus faecium from China.

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Cai, Jia Chang; Hu, Yan Yan; Zhang, Rong; Zhou, Hong Wei; Chen, Gong-Xiang

2012-11-01

Seventeen meticillin-resistant coagulase-negative staphylococci (MRCoNS), including ten Staphylococcus capitis, four Staphylococcus cohnii, two Staphylococcus haemolyticus and one Staphylococcus sciuri, and an Enterococcus faecium isolate with various levels of linezolid resistance were isolated from intensive care units in a Chinese hospital. PFGE indicated that the four S. cohnii isolates belonged to a clonal strain, and that nine of the S. capitis isolates were indistinguishable (clone A1) and the other one was closely related (clone A2). A G2576T mutation was identified in domain V of the 23S rRNA gene in the E. faecium isolate. Besides the G2576T mutation, a novel C2104T mutation was detected in the nine clone A1 S. capitis isolates. The cfr gene was detected in all the staphylococci except an S. sciuri isolate, whose 23S rRNA gene contained the G2576T mutation. There was a clonal dissemination of linezolid-resistant MRCoNS in intensive care units of our hospital, and this is the first report, to our knowledge, of linezolid-resistant staphylococci and enterococci in China.

Antimicrobial Resistance Profile of Planktonic and Biofilm Cells of Staphylococcus aureus and Coagulase-Negative Staphylococci

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Adilson de Oliveira

2016-09-01

Full Text Available The objective of the present study was to determine the antimicrobial resistance profile of planktonic and biofilm cells of Staphylococcus aureus and coagulase-negative staphylococci (CoNS. Two hundred Staphylococcus spp. strains were studied, including 50 S. aureus and 150 CoNS strains (50 S. epidermidis, 20 S. haemolyticus, 20 S. warneri, 20 S. hominis, 20 S. lugdunensis, and 20 S. saprophyticus. Biofilm formation was investigated by adherence to polystyrene plates. Positive strains were submitted to the broth microdilution method to determine the minimum inhibitory concentration (MIC for planktonic and biofilm cells and the minimal bactericidal concentration for biofilm cells (MBCB. Forty-nine Staphylococcus spp. strains (14 S. aureus, 13 S. epidermidis, 13 S. saprophyticus, 3 S. haemolyticus, 1 S. hominis, 3 S. warneri, and 2 S. lugdunensis were biofilm producers. These isolates were evaluated regarding their resistance profile. Determination of planktonic cell MIC identified three (21.4% S. aureus strains that were resistant to oxacillin and six (42.8% that were resistant to erythromycin. Among the CoNS, 31 (88.6% strains were resistant to oxacillin, 14 (40% to erythromycin, 18 (51.4% to gentamicin, and 8 (22.8% to sulfamethoxazole/trimethoprim. None of the planktonic isolates were resistant to vancomycin or linezolid. MICs were 2-, 4-, 8-, and up to 16-fold higher for biofilm cells than for planktonic cells. This observation was more common for vancomycin and erythromycin. The MBCB ranged from 8 to >256 µg/mL for oxacillin, 128 to >128 µg/mL for vancomycin, 256 to >256 µg/mL for erythromycin and gentamicin, >64 µg/mL for linezolid, and 32/608 to >32/608 µg/mL for sulfamethoxazole/trimethoprim. The results showed considerably higher MICs for S. aureus and CoNS biofilm cells compared to planktonic cells. Analysis of MBCM confirmed that even high concentrations of vancomycin were unable to eliminate the biofilms of S. aureus and CoNS

Acceleration of direct identification of S.aureus versus Coagulase Negative Staphylococci from blood culture material: a comparison of six bacterial DNA extraction methods

NARCIS (Netherlands)

Prof. Dr. C.A. Bruggeman; Drs H. Kreeftenberg; Dr. Ir. P.F.G. Wolffs; Drs A.J.M. Loonen; Dr. A.J.C. van den Brule, van den; Drs A.R. Jansz

2010-01-01

To accelerate differentiation between Staphylococcus aureus and Coagulase Negative Staphylococci (CNS), this study aimed to compare six different DNA extraction methods from 2 commonly used blood culture materials, i.e. BACTEC and Bact/ALERT. Furthermore, we analyzed the effect of reduced blood

Staphylococcus chromogenes, a Coagulase-Negative Staphylococcus Species That Can Clot Plasma

OpenAIRE

dos Santos, Danielle Cabral; Lange, Carla Christine; Avellar-Costa, Pedro; dos Santos, Katia Regina Netto; Brito, Maria Aparecida Vasconcelos Paiva; Giambiagi-deMarval, Marcia

2016-01-01

Staphylococcus chromogenes is one of the main coagulase-negative staphylococci isolated from mastitis of dairy cows. We describe S. chromogenes isolates that can clot plasma. Since the main pathogen causing mastitis is coagulase-positive Staphylococcus aureus, the coagulase-positive phenotype of S. chromogenes described here can easily lead to misidentification.

Staphylococcus chromogenes, a Coagulase-Negative Staphylococcus Species That Can Clot Plasma

Science.gov (United States)

dos Santos, Danielle Cabral; Lange, Carla Christine; Avellar-Costa, Pedro; dos Santos, Katia Regina Netto; Brito, Maria Aparecida Vasconcelos Paiva

2016-01-01

Staphylococcus chromogenes is one of the main coagulase-negative staphylococci isolated from mastitis of dairy cows. We describe S. chromogenes isolates that can clot plasma. Since the main pathogen causing mastitis is coagulase-positive Staphylococcus aureus, the coagulase-positive phenotype of S. chromogenes described here can easily lead to misidentification. PMID:26912749

Prevalence of enterotoxin-encoding genes and antimicrobial resistance in coagulase-negative and coagulase-positive Staphylococcus isolates from black pudding

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Tiane Martin de Moura

2012-10-01

Full Text Available INTRODUCTION: Staphylococcal species are pathogens that are responsible for outbreaks of foodborne diseases. The aim of this study was to investigate the prevalence of enterotoxin-genes and the antimicrobial resistance profile in staphylococcus coagulase-negative (CoNS and coagulasepositive (CoPS isolates from black pudding in southern Brazil. METHODS: Two hundred typical and atypical colonies from Baird-Parker agar were inoculated on mannitol salt agar. Eighty-two mannitol-positive staphylococci were submitted to conventional biochemical tests and antimicrobial susceptibility profiling. The presence of coagulase (coa and enterotoxin (se genes was investigated by polymerase chain reaction. RESULTS: The isolates were divided into 2 groups: 75.6% (62/82 were CoNS and 24.4% (20/82 were CoPS. The biochemical tests identified 9 species, of which Staphylococcus saprophyticus (37.8% and Staphylococcus carnosus (15.9% were the most prevalent. Antimicrobial susceptibility tests showed resistance phenotypes to antibiotics widely administered in humans, such as gentamicin, tetracycline, chloramphenicol, and erythromycin. The coa gene was detected in 19.5% (16/82 of the strains and 4 polymorphic DNA fragments were observed. Five CoNS isolates carrying the coa gene were submitted for 16S rRNA sequencing and 3 showed similarity with CoNS. Forty strains were positive for at least 1 enterotoxin-encoding gene, the genes most frequently detected were sea (28.6% and seb (27.5%. CONCLUSIONS: The presence of antimicrobial resistant and enterotoxin-encoding genes in staphylococci isolates from black pudding indicated that this fermented food may represent a potential health risk, since staphylococci present in food could cause foodborne diseases or be a possible route for the transfer of antimicrobial resistance to humans.

Bacterial biofilms with emphasis on coagulase-negative staphylococci

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A Oliveira

2008-01-01

Full Text Available In addition to their capacity to attach to surfaces, various groups of microorganisms also produce an extracellular polymeric substance known as "slime". This slime forms a thin layer around cells known as biofilm. Thus, biofilm structure comprises bacterial cells and an extracellular polymeric substance. It also presents a defined architecture, providing the microorganisms with an excellent protective environment and favoring the exchange of genetic material between cells as well as intercellular communication. The ability to produce biofilm is observed in a large group of bacteria, including coagulase-negative staphylococci (CNS which are the predominant microorganisms of normal skin flora and have been implicated as the causative agents of hospital infections. Bacteremia caused by these agents is common in immunodepressed persons, in patients with cancer, in adult and neonatal intensive care units (ICU and in patients using catheters or other prosthetic devices. The pathogenicity of CNS infections is probably related to the production of slime, which adheres preferentially to plastic and smooth surfaces, forming a biofilm that protects against attacks from the immune system and against antibiotic treatment, a fact hindering the eradication of these infections. The main objective of the present review was to describe basic and genetic aspects of biofilm formation and methods for its detection, with emphasis on biofilm creation by CNS and its relationship with diseases caused by these microorganisms which are becoming increasingly more frequent in the hospital environment.

Antimicrobial susceptibility pattern and SCCmec types of methicillin-resistant coagulase-negative staphylococci from subclinical bovine mastitis in Hatay, Turkey

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Aslantaş Özkan

2014-12-01

Full Text Available Eighty-nine isolates of coagulase-negative staphylococci (CoNS of eight species from subclinical bovine mastitis were screened for the phenotypic and genotypic methicilline-resistance. In addition, all methicillin-resistant (MR isolates indicating the mecA gene were examined by PCR for the antimicrobial susceptibility patterns, and staphylococcal cassette chromosome mec (SCCmec types were also determined by multiplex PCR. A total of 21 (23.6% CoNS isolates were found to be resistant to oxacillin in broth microdilution assay. All isolates phenotypically resistant to oxacillin did not have the mecA gene, which was only found in 14.6% (13 of the isolates. Most MR-CoNS isolates were highly resistant to erythromycin (92.3%, fusidic acid (84.6%, penicillin (76.9%, and rifampycin (61.5%, and susceptible to mupirocin (100%, tetracycline (100%, vancomycin (100%, clindamycin (92.3%, and sulfamethoxazole-trimethoprim (69.2%. In conclusion, a high rate of antimicrobial resistance among MR-CoNS isolated from food producing animals emphasises the need for periodic surveillance of their resistance.

Prevalence and antimicrobial resistance of coagulase negative staphylococci clinical isolates from Ethiopia: a meta-analysis.

Science.gov (United States)

Deyno, Serawit; Fekadu, Sintayehu; Seyfe, Sisay

2018-05-25

Antimicrobial resistant Coagulase-negative Staphylococci (CoNS) have limited treatment options, rendered diseases untreatable and made hospitals to be reservoirs of the resistant strains. The aim of this study was to estimate the pooled prevalence and antimicrobial resistance of clinical isolates of CoNS from Ethiopia. The electronic database search yielded 6511 articles of which 21 met predefined inclusion criteria. The pooled prevalence of CoNS from Ethiopia was 12% (95% confidence interval (CI): 8, 16%). The analyses revealed high level of CoNS resistance to methicilin (37%[95% CI: 21, 55%]), vancomycin (911%[95% CI: 0, 35%]), penicillin (58%[95% CI: 42, 74%]), amoxicillin (42%[95% CI: 23, 61%]), amoxicillin-clavulanate (27%[95% CI: 2, 27%]), ampicillin (64%[95% CI: 46, 80%]), tetracycline (60% [95% CI: 49, 70%]), doxycycline (36%[95% CI:19,55%]), Sulfamethoxazole-trimethoprim (50%[95% CI: 36, 64%]), ceftriaxone (27% [95% CI: 18, 38%]), cephalothin (32% [95% CI: 7, 62%]), norfloxacin (39%[95% CI: 24, 56%]), chloramphenicol (40%[95% CI: 23, 58%]), clindamycin (11% [95% CI: 2, 27%]), ciprofloxacin (14%[95% CI: 6, 22%]), gentamicin (27%[95% CI:19,36%]) and erythromycin (30%[95% CI:20%,42%]). High heterogeneity, I 2 ranging from 69.04 to 96.88%; p-values ≤0.01, was observed. Eggers' test did not detect publication bias for the meta-analyses and low risk of bias was observed in included studies. CoNS has gotten resistant to commonly used antimicrobials from Ethiopia. There is a need of launching national antimicrobial treatment, development and implementation of policy guidelines to contain the threat. Further research focusing on factors promoting resistance and the effect of resistance on treatment outcome studies are warranted.

Staphylococcus chromogenes, a Coagulase-Negative Staphylococcus Species That Can Clot Plasma.

Science.gov (United States)

Dos Santos, Danielle Cabral; Lange, Carla Christine; Avellar-Costa, Pedro; Dos Santos, Katia Regina Netto; Brito, Maria Aparecida Vasconcelos Paiva; Giambiagi-deMarval, Marcia

2016-05-01

Staphylococcus chromogenes is one of the main coagulase-negative staphylococci isolated from mastitis of dairy cows. We describe S. chromogenes isolates that can clot plasma. Since the main pathogen causing mastitis is coagulase-positive Staphylococcus aureus, the coagulase-positive phenotype of S. chromogenes described here can easily lead to misidentification. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Rapid detection of methicillin resistance in coagulase-negative staphylococci by a penicillin-binding protein 2a-specific latex agglutination test.

Science.gov (United States)

Horstkotte, M A; Knobloch, J K; Rohde, H; Mack, D

2001-10-01

The detection of PBP 2a by the MRSA-Screen latex agglutination test with 201 clinical coagulase-negative staphylococci had an initial sensitivity of 98% and a high degree of specificity for Staphylococcus epidermidis strains compared to PCR for mecA. Determination of oxacillin MICs evaluated according to the new breakpoint (0.5 microg/ml) of the National Committee for Clinical Laboratory Standards exhibited an extremely low specificity for this population.

Antibacterial activities of coagulase-negative staphylococci from bovine teat apex skin and their inhibitory effect on mastitis-related pathogens.

Science.gov (United States)

Braem, G; Stijlemans, B; Van Haken, W; De Vliegher, S; De Vuyst, L; Leroy, F

2014-05-01

To explore antibacterial activities of coagulase-negative staphylococci (CoNS) from teat apices of dairy cows towards mastitis-causing pathogens. Of 254 CoNS, 38 displayed bacteriocin-like activity after a first screening. Seven of these strains displayed activity against at least one mastitis-related pathogen (Streptococcus uberis, Streptococcus dysgalactiae and Staphylococcus aureus). Staphylococcus chromogenes L217 displayed the strongest inhibitory effect, being active against all tested mastitis-related pathogens and most tested CoNS. Based on cation exchange and reversed-phase chromatography, in addition to N-terminal Edman degradation and PCR, the antibacterial peptide was identified as a nukacin-type bacteriocin and named nukacin L217. Although staphylococcal bacteriocins are generally found in the cell-free supernatants of liquid cultures, Staph. chromogenes L217 only led to detectable activity when grown on agar medium. Bacteriocin-like activities are not uncommon among CoNS from teat apices and may inhibit mastitis-causing pathogens, as found for nukacin L217 production by Staph. chromogenes L217. Nukacin L217 is the first identified bacteriocin of the species Staph. chromogenes and displays unusual production kinetics, that is, requiring surface growth of its producer. The fact that nukacins are produced by different CoNS species suggests a role in the teat skin ecosystem. © 2014 The Society for Applied Microbiology.

Antimicrobial susceptibility of coagulase-negative Staphylococci isolated from mastitic cattle in Brazil Susceptibilidade antimicrobiana de cepas de Staphylococci coagulase-negativa isoladas de leite de bovinos com mastite no Brasil

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T.R.O. Machado

2008-02-01

Full Text Available Um total de 109 cepas de Staphylococci coagulase-negativa foi isolado de leite de vacas com mastite clínica e subclínica, em 35 fazendas, situadas em nove estados brasileiros, no período de fevereiro a maio de 2005. Os isolados foram investigados em relação a susceptibilidade in vitro a diversos agentes antimicrobianos. A resistência à penicilina foi a observação mais freqüente (93,5%, seguida por sulfonamida (88,9%, novobiocina (88,6% e ampicilina (85,3%. Todas as cepas examinadas mostraram resistência a pelo menos uma das drogas antimicrobianas testadas. Cepas apresentando resistência múltipla foram extremamente comuns, com 10,0% dos microrganismos isolados apresentando resistência a todas as drogas antimicrobianas. Os resultados obtidos indicaram que as cepas de Staphylococci coagulase-negativas, isoladas no Brasil, apresentaram um alto grau de resistência a antimicrobianos. Estes resultados são, provavelmente, uma conseqüência da pressão devida ao uso intensivo de drogas antimicrobianas.

Rapid Detection of Methicillin Resistance in Coagulase-Negative Staphylococci by a Penicillin-Binding Protein 2a-Specific Latex Agglutination Test

OpenAIRE

Horstkotte, Matthias A.; Knobloch, Johannes K.-M.; Rohde, Holger; Mack, Dietrich

2001-01-01

The detection of PBP 2a by the MRSA-Screen latex agglutination test with 201 clinical coagulase-negative staphylococci had an initial sensitivity of 98% and a high degree of specificity for Staphylococcus epidermidis strains compared to PCR for mecA. Determination of oxacillin MICs evaluated according to the new breakpoint (0.5 μg/ml) of the National Committee for Clinical Laboratory Standards exhibited an extremely low specificity for this population.

Antibiotic Susceptibility of Coagulase-Negative Staphylococci Isolated from Bovine Subclinical Mastitis in Turkey

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Beytullah Kenar*, Yahya Kuyucuoğlu and Esra Şeker

2012-06-01

Full Text Available A total of 572 California Mastitis Test (CMT positive milk samples were collected from 423 lactating cows on 18 private farms in the Middle Western Anatolia. Coagulase–negative staphylococci colonies and CNS species identification was performed based on conventional biochemical techniques and using the API Staph test. Slime production was detected by Congo Red Agar (CRA method. The antibiotic susceptibility was determined according to the National Committee for Clinical Laboratory Standards guidelines (NCCLS. A total of 67 (11.7% coagulase-negative staphylococci (CNS were isolated from CMT positive milk samples. In total, 11 CNS species: S. epidermidis (n=18, S. simulans (n=14, S. warneri (n=10, S. hominis (n=5, S. chromogenes (n=4, S. caprae (n=4, S. xylosus (n=3, S. haemolyticus (n=3, S. hyicus (n=3, S. cohnii (n=2, and S. capitis (n=1 were identified. The most commonly identified CNS species were Staphylococcus epidermidis (26.8% and Staphylococcus simulans (20.8% followed by Staphylococcus warneri (14.9%. Out of 67 CNS isolates, slime production was found in 37 (55.2% CNS strains. CNS isolates were the most resistance to trimethoprim+sulphamethoxazole (76.2%, erythromycin (73.2%, oxacillin and ampicillin (70.2% followed by penicillin (58.3%, gentamicin (53.8%, tetracycline (52.3%, vancomycin (51.8%, ciprofloxacin (26.9%, cefoxitim (23.9%, and cephalothin (13.5%. These results indicate that CNS species are resistant at high rates to the beta-lactam antibiotics which are intensively used in the prevention and treatment of mastitis without any antibiotic susceptibility test in the Middle Western of Turkey.

Safety Evaluation of the Coagulase-Negative Staphylococci Microbiota of Salami: Superantigenic Toxin Production and Antimicrobial Resistance

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Raquel Soares Casaes Nunes

2015-01-01

Full Text Available The risks of contracting staphylococci food poisoning by the consumption of improperly manufactured salami and the possibility of this food being reservoirs for antibiotic resistance were evaluated. Nineteen coagulase-negative staphylococci (CNS strains were found in commercial and artisanal salami. The species in commercial salami were S. saprophyticus, S. sciuri, S. xylosus, and S. carnosus. Artisanal salami showed S. succinus, S. epidermidis, and S. hominis but no S. carnosus. Phylogenetic analyses grouped the strains into three major staphylococcal species groups, comprised of 4 refined clusters with similarities superior to 90%. Fifteen strains harbored multiple enterotoxin genes, with high incidence of seb/sec and sea, 57% and 50%, respectively, intermediate incidence of sed/seh/selm and sei/seln/tst-H, 33% and 27%, correspondingly, and low incidence of see/selj/selo and seg, of respectively 13% and 1%. Real time RT-PCR and enzyme-linked-immunosorbent assays confirmed the enterotoxigenicity of the strains, which expressed and produced enterotoxins in vitro. The CNS strains showed multiresistance to several antimicrobials of therapeutic importance in both human and veterinarian medicine, such as β-lactams, vancomycin, and linezolid. The effective control of undue staphylococci in fermented meat products should be adopted to prevent or limit the risk of food poisoning and the spread of antimicrobial-resistant strains.

Nasal carriage of methicillin resistant staphylococci

DEFF Research Database (Denmark)

Faria, Nuno A; Conceição, Teresa; Miragaia, Maria

2014-01-01

Coagulase-negative staphylococci (CoNS) are believed to function as reservoirs, as well as possible sources of staphylococcal chromosome cassette mec (SCCmec) to Staphylococcus aureus, but the frequency, preferred partners, and factors promoting SCCmec transfer are not known. Such postulated...

Prevalence and antibiotic resistance of coagulase-negative Staphylococci isolated from poultry farms in three regions of Ghana

DEFF Research Database (Denmark)

Boamah, Vivian Etsiapa; Agyare, Christian; Odoi, Hayford

2017-01-01

The use of antibiotics in animal production has been associated with the development and spread of antibiotic-resistant organisms including commensals. Coagulase-negative Staphylococcus (CoNS) species, which were until recently considered non-pathogenic, have been associated with opportunistic...... usage in both animal production and in humans....... infections and high resistance to several antibiotics. This study sought to determine the prevalence, identity, and phenotypic resistance of coagulase-negative Staphylococcus spp. isolated from some selected poultry farms and farm workers in the Ashanti, Brong Ahafo, and Greater Accra regions of Ghana...

A study of coagulase-negative staphylococci (CoNS isolated from bovine mastitis for the presence of penicillin and methicillin resistance-encoding genes in the north west of Iran

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Dastmalchi Saei, H.

2014-11-01

Full Text Available Coagulase-negative staphylococci (CoNS are often associated with bovine mastitis and may be resistant to antimicrobial therapy. The aim of the current study was to investigate the presence of blaZ (responsible for penicillin resistance and mecA (responsible for methicillin resistance genes among 108 CoNS belonging to 9 different species isolated from bovine mastitis in seven dairy herds (H1-H7. Of 108 CoNS isolates, 44 were Staphylococcus haemolyticus, 17 S. chromogenes, 11 S. epidermidis, 11 S. warneri, 11 S. cohnii, 6 S. simulans, 4 S. hominis, 3 S. capitis, and 1 S. xylosus. The blaZ was detected in 65.7% (n=71 of all Staphylococcus spp. isolates. Five isolates were positive for the presence of mecA gene (4.6%, including 2 S. hominis, 1 S. haemolyticus, 1 S. epidermidis, and 1 S. warneri. All mecA-carrying CoNS were also positive for the blaZ gene and were recovered from two studied herds (H3 and H6. Some variations were also observed in distribution of both blaZ and mecA genes between CoNS species. This study demonstrates that CoNS from bovine mastitis can be reservoirs of blaZ gene. This study also provides evidence of the presence of methicillin resistant CoNS (MR-CoNS and emphasizes the need for their epidemiological monitoring, in order to prevent the risk of spread to human through direct contact and/or consumption of contaminated food.

Genotypic Characterization of Coagulase-negative Staphylococci Isolated from Sheep Milk in Slovakia

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Ivana Pilipčincová

2010-01-01

Full Text Available Hitherto very few reports are available presenting identification and molecular characterization of the coagulase negative staphylococci (CNS from sheep milk in the subclinical stage of mastitis. Furthermore, very scanty data are available on the epidemiological status of CNS in different Slovak provinces. Milk samples from 54 sheep farms located in eastern Slovak region were screened. A total 240 CNS were identified with series of biochemical testes (STAPH-API and subjected further for genotyping with the help of pulse field gel electrophoresis (PFGE. The most frequently occurring CNS species according the biochemical characterization were: S. epidermidis (36.3 %, S. caprae (21.3 %, S. hominis (6.6 %, S. chromogenes (6.3 %, S. xylosus (5.8 %, S. warneri (5.0 % and S. capitis (4.6 %. Further PFGE-based characterization of these isolates revealed six pulsotypes of the S. epidermidis, two of S. caprae, three of S. chromogenes, nine of S. hominis, five of S. capitis and seven of S. xylosus. These results contribute to knowledge of the epidemiological situation of the CNS from the subclinical form of mastitis in Slovakia.

Prevalence and antimicrobial resistance pattern of coagulase ...

African Journals Online (AJOL)

Prevalence and antimicrobial resistance pattern of coagulase negative Staphylococci isolated from pigs and in-contact humans in Jos Metropolis, Nigeria. ... (53/401) of the isolates were CoNS species based on confirmatory test with Microgen biochemical kit and were further subjected to antibiotic susceptibility testing.

A novel MSCRAMM sub-family in Coagulase negative staphylococcal species

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Srishtee eArora

2016-04-01

Full Text Available Coagulase negative staphylococci are important opportunistic pathogens. Staphylococcus epidermidis, a coagulase negative staphylococcus, is the third leading cause of nosocomial infections in the US. Surface proteins like Microbial Surface Components Recognizing Adhesive Matrix Molecules (MSCRAMMs are major virulence factors of pathogenic gram positive bacteria. Here, we identified a new chimeric protein; SesJ in S. epidermidis, which represents a prototype of a new subfamily of MSCRAMMs. Structural predictions show that SesJ has structural features characteristic of a MSCRAMM along with a N-Terminal repeat region and an Aspartic acid containing repeat region, features that have not been previously observed in staphylococcal MSCRAMMs but have been found in other surface proteins from gram positive bacteria. We identified and analyzed structural homologs of SesJ in three other coagulase negative staphylococci. These homologs of SesJ have an identical structural organization but varying sequence identities within the domains. Using flow cytometry, we also show that SesJ is expressed constitutively on the surface of a representative S. epidermidis strain, from early exponential to stationary growth phase. Thus SesJ is positioned to interact with protein targets in the environment and play a role in S. epidermidis virulence.

Antimicrobial susceptibility of coagulase-negative staphylococci isolated from meat-producing ewes with mastitis

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A.M.M.P Della Libera

2010-12-01

Full Text Available Avaliou-se a sensibilidade antimicrobiana in vitro de 121 cepas de estafilococos coagulase-negativa isolada de leite de ovelhas Santa Inês, aos fármacos: penicilina, amoxicilina, ampicilina, estreptomicina, oxaciclina, neomicina, cefalotina, gentamicina e sulfonamida. A resistência à sulfonamida foi a mais frequente (27,3%, seguida pela estreptomicina (14,0% e pela oxaciclina (14,0%, enquanto da gentamicina (1,6% foi a menos frequente. Todas as cepas foram sensíveis a pelo menos um antimicrobiano, e 20,3% das cepas apresentaram resistência múltipla. Os resultados mostram a importância de Staphylococci coagulase-negativas como agentes causadores de mastite em ovinos, e o perfil de resistência múltipla indica a importância da determinação da resistência à oxaciclina como indicador da presença de ilhas de patogenicidade que contêm fatores de virulência e resistência a outros antimicrobianos que contribuem para a sobrevivência da bactéria ao tratamento.

Transmission dynamics and resistance in staphylococci

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Hetem, D.J.

2015-01-01

This thesis will focus on nosocomial transmission and resistance of S. aureus and CoNS. After the general introduction on S. aureus and coagulase-negative staphylococci, part II focuses on the nosocomial transmission capacity of different MRSA clones in the hospital setting. In chapter 2 the

Species Distribution and Antibiotic Resistance in Coagulase ...

African Journals Online (AJOL)

Purpose: The antimicrobial susceptibility of 149 coagulase-negative staphylococci (CoNS) isolates from faecal samples of children in Ile-Ife, Nigeria, was evaluated in order to determine their contribution to antimicrobial resistance in the community. Methods: The isolates were identified to the species level by conventional ...

Antibiotic Resistance in Staphylococcus aureus and Coagulase Negative Staphylococci Isolated from Goats with Subclinical Mastitis

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Salvatore Virdis

2010-01-01

Full Text Available Antimicrobial resistance patterns and gene coding for methicillin resistance (mecA were determined in 25 S. aureus and 75 Coagulase Negative Staphylococci (CNS strains isolates from half-udder milk samples collected from goats with subclinical mastitis. Fourteen (56.0% S. aureus and thirty-one (41.3% CNS isolates were resistant to one or more antimicrobial agents. S. aureus showed the highest resistance rate against kanamycin (28.0%, oxytetracycline (16.0%, and ampicillin (12.0%. The CNS tested were more frequently resistant to ampicillin (36.0% and kanamycin (6.7%. Multiple antimicrobial resistance was observed in eight isolates, and one Staphylococcus epidermidis was found to be resistant to six antibiotics. The mecA gene was not found in any of the tested isolates. Single resistance against β-lactamics or aminoglicosides is the most common trait observed while multiresistance is less frequent.

Characterization of Coagulase-Negative Staphylococci and pheno-genotypic beta lactam resistance evaluation in samples from bovine Intramammary infection

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D.A. Melo

Full Text Available ABSTRACT This study aimed to identify Coagulase-Negative Staphylococci (CoNS species isolated from bovine mastitis, through phenotypic and PCR-RFLP (Restriction Fragment Length Polymorphism-Polimerase Chain Reaction methods and to compare both techniques to matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS technique. Among them, the PCR-RFLP method, using a partially conserved sequence of the groEL gene, is a promising alternative, because of its reproducibility and reliability. On the other hand, the proteomic technique MALDI-TOF MS provides an accurate and much faster diagnosis and has been increasingly employed in microbiological identification. The pheno-genotypic profiles of beta-lactam resistance were also investigated, this characterization is important, considering that the use of antimicrobials is a key element for mastitis control in dairy farms. The concordance of the phenotypic, PCR-RFLP and MALDI-TOF MS assays to identify CoNS species was 77,5% (31/40. S. chromogenes was the species most frequently isolated. Antibiotic resistance rate was relatively low, registering values of 25.5% to penicillin, 9.6% to oxacillin and 6.2% to cefoxitin. Resistance to imipenem, cephalotin and amoxicillin+clavulanate was not observed. The mecA gene and its variant were detected in 7.6% and 4,1% of the isolates respectively. The blaZ gene was found in 43.2% of the strains resistant to penicillin.

Species-specific sensitivity of coagulase-negative Staphylococci to single antibiotics and their combinations.

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Szymańska, Grazyna; Szemraj, Magdalena; Szewczyk, Eligia M

2011-01-01

The activity of beta-lactam antibiotics (oxacillin, cloxacillin, cephalotin), vancomycin, gentamicin and rifampicin applied in vitro individually and in combination against 37 nosocomial methicillin-resistant strains of coagulase-negative staphylococci (CNS) was assessed to demonstrate the heterogeneity of this group of bacteria and estimate the chance of the efficacy of such therapy. The strains belonged to four species: Staphylococcus epidermidis, Staphylococcus haemolyticus, Staphylococcus cohnii, Staphylococcus hominis. They originated from a hospital environment and from the skin of medical staff of the intensive care unit of a paediatric ward at a university hospital. All strains were methicillin-resistant, according to CLSI standards, but individual strains differed in MIC(ox) values. Susceptibility to other tested antibiotics was also characteristic for the species. The increased susceptibility to antibiotics in combinations, tested by calculating the fractional inhibitory concentration (FIC) index, concerned 26 out of 37 investigated strains and it was a feature of a particular species. Combinations of vancomycin and cephalotin against S. epidermidis and oxacillin with vancomycin were significant, as well as cephalotin and rifampicin in growth inhibition of multiresistant S. haemolyticus strains.

Identification of Coagulase-Negative Staphylococci from Bovine Intramammary Infection by Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry

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Gonçalves, Juliano Leonel; Barreiro, Juliana Regina; Braga, Patrícia Aparecida de Campos; Prada e Silva, Luis Felipe; Eberlin, Marcos Nogueira

2014-01-01

Coagulase-negative staphylococci (CoNS) are among the main pathogens causing bovine intramammary infection (IMI) in many countries. However, one of the limitations related to the specific diagnosis of CoNS is the lack of an accurate, rapid, and convenient method that can differentiate the bacterial species comprising this group. The aim of this study was to evaluate the ability of matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) to accurately identify CoNS species in dairy cow IMI. In addition, the study aimed to determine the frequency of CoNS species causing bovine IMI. A total of 108 bacterial isolates were diagnosed as CoNS by microbiological cultures from two milk samples collected from 21 dairy herds; the first sample was collected at the cow level (i.e., 1,242 composite samples from all quarters), while the second sample was collected at the mammary quarter level (i.e., 1,140 mammary samples collected from 285 cows). After CoNS isolation was confirmed by microbiological culture for both samples, all CoNS isolates (n = 108) were genotypically differentiated by PCR restriction fragment length polymorphism (RFLP) analysis of a partial groEL gene sequence and subjected to the MALDI-TOF MS identification procedure. MALDI-TOF MS correctly identified 103 (95.4%) of the CoNS isolates identified by PCR-RFLP at the species level. Eleven CoNS species isolated from bovine IMI were identified by PCR-RFLP, and the most prevalent species was Staphylococcus chromogenes (n = 80; 74.1%). In conclusion, MALDI-TOF MS may be a reliable alternative method for differentiating CoNS species causing bovine IMI. PMID:24622096

Phenotypical and Genotypical Antimicrobial Resistance of Coagulase-negative staphylococci Isolated from Cow Mastitis.

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Klimiene, I; Virgailis, M; Pavilonis, A; Siugzdiniene, R; Mockeliunas, R; Ruzauskas, M

2016-09-01

The objectives of this study were to determine the prevalence and antimicrobial resistance of coagulase-negative staphylococci (CNS) isolated from dairy cows with subclinical mastitis. Antimicrobial resistance in staphylococci were evaluated by breakpoint values specific to the species (EU-CAST). The presence of resistance-encoding genes was detected by multiplex PCR. A total of 191 CNS isolates were obtained. The CNS isolates were typically resistant to penicillin (67.4%), tetracyc-line (18.9%), and erythromycin (13.7%). CNS isolates (78.0%) were resistant to at least one antimicrobial compound, and 22.0% were multiresistant. The multiresistant isolates were predominantly Staphylococcus chromogenes (28.6%), Staphylococcus warneri (19%) and Staphylococcus haemolyticus (14.3%). According to MIC pattern data, multiresistant isolates showed the highest resistance (p<0.05) rates to penicillin (85.7%), tetracycline (66.7%), and erythromycin (48.2%), but all of them were sensitive to daptomycin, oxacillin, qiunupristin/dalfopristin, and vancomycin. S. chromogenes (9.5%), S. haemolyticus (4.8%), and S. capitis ss capitis (2.4%) strains were resistant to methicillin; their resistance to oxacillin and penicillin was more than 8 mg/l. A high rate of resistance to penicillin was linked to a blaZ gene found in 66.6% of the isolated multiresistant CNS strains. Resistance to tetracycline via the tetK (38.1%) gene and penicillin via the mecA (23.8%) gene were detected less frequently. Gene msrAB was responsible for macrolides and lincosamides resistance and detected in 28.6% of the CNS isolates. Antimicrobial resistance genes were identified more frequently in S. epidermidis, S. chromogenes, and S. warneri.

Staphylococcal species associated with bovine mastitis in the North West of Iran: Emerging of coagulase-negative staphylococci

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Somayyeh Hosseinzadeh

2014-06-01

Full Text Available Staphylococcal mastitis is a major and costly problem of dairy cattle all over the world. The objective of this study was to isolate and identify the main staphylococcal species causing bovine mastitis in 7 dairy herds located in 4 different areas of East and West Azerbaijan provinces, Iran. Of the 158 mastitic milk samples collected, 113 staphylococcal isolates were identified (71.5% on the basis of cultural and biochemical features as well as by genus specific PCR. Then, species level identification of staphylococcal isolates was carried out using restriction fragment length polymorphism (RFLP analysis of the gap gene (933 bp. On the basis of polymerase chain reaction-RFLP, 10 different patterns were identified. Of 113 isolates, 5 (4.4% were Staphylococcus aureus and 108 (95.6% were coagulase-negative staphylococci (CoNS. Overall, nine different species of CoNS were identified as: 44 Staphylococcus haemolyticus (40.7%, 17 Staphylococcus chromogenes (15.7%, 11 Staphylococcus epidermidis, Staphylococcus warneri and Staphylococcus cohnii each (10.2%, 6 Staphylococcus simulans (5.5%, 4 Staphylococcus hominis (3.7%, 3 Staphylococcus capitis (2.7% and 1 Staphylococcus xylosus (0.9%. S. haemolyticus, S. chromogenes and S. warneri were the only species identified from clinical mastitis. No significant difference in staphylococcal IMI was found among the studied herds and regions. This study demonstrated that CoNS, especially S. haemolyticus and S. chromogenes, were predominant and thus be considered as emerging pathogens causing mastitis in the North West of Iran. Our results also revealed that the gap PCR-RFLP was useful for identifying staphylococcal isolates derived from bovine mastitis at species level.

Microbial Diversity in Milk of Women With Mastitis: Potential Role of Coagulase-Negative Staphylococci, Viridans Group Streptococci, and Corynebacteria.

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Mediano, Pilar; Fernández, Leonides; Jiménez, Esther; Arroyo, Rebeca; Espinosa-Martos, Irene; Rodríguez, Juan M; Marín, María

2017-05-01

Lactational mastitis constitutes a significant cause of premature weaning. However, its etiology, linked to the presence of pathogenic microorganisms, has been scarcely reported. Research aim: The aim of this study was to describe the microbial diversity in milk samples from women suffering from lactational mastitis and to identify more accurately a collection of isolates belonging to coagulase-negative staphylococci, streptococci, and coryneform bacteria. This is a cross-sectional descriptive one-group study. A total of 5,009 isolates from 1,849 mastitis milk samples was identified by culture, biochemical, and/or molecular methods at the species or genus level. A more precise identification of a collection of 211 isolates was carried out by 16S rRNA gene sequencing. Mean total bacterial count in milk samples was 4.11 log 10 colony-forming units/ml, 95% confidence interval [4.08, 4.15]. Staphylococcus epidermidis was the most common species being isolated from 91.56% of the samples, whereas Staphylococcus aureus was detected in 29.74%. Streptococci and corynebacteria constituted the second (70.20%) and third (16.60%) most prevalent bacterial groups, respectively, found in this study. In contrast, Candida spp. was present in only 0.54% of the samples. Sequencing of the 16S rRNA gene revealed a high diversity of bacterial species among identified isolates. Many coagulase-negative staphylococci, viridans group streptococci, and corynebacteria, usually dismissed as contaminant bacteria, may play an important role as etiologic agents of mastitis. Proper diagnosis of mastitis should be established after performing microbiological testing of milk based on standardized procedures. A reliable analysis must identify the mastitis-causing pathogen(s) at the species level and its(their) concentration(s).

The effects of four different drugs administered through catheters on slime production in coagulase negative Staphylococci

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J. Sedef Göçmen

2012-12-01

Full Text Available Objectives: Higher rate of slime production has been found in pathogen bacteria strains. Accordingly, the factors thatcontribute to higher slime production rate increase the infection risk, while the factors that reduce the slime productionrate will reduce the infection risk. The effect of some drugs that are administered through catheters in intensive careunits on slime production with coagulase negative Staphylococci was investigated.Materials and methods: In this study, the effect of four different preparations containing Glyceryl trinitrate (Perlinganit®, Dexmedetomidine (Precedex®, Esmolol (Brevibloc®, and Propofol (Propofol® on slime production of 24Staphylococcus epidermidis strains isolated from blood cultures of patients, and reference strain were investigated. Slimeproduction was determined using ‘the quantitative microdilution plaque test’ described by Christensen.Results: Under controlled medium, eight strains formed slimes, and in the media containing esmolol, glyceryl trinitrate,dexmedetomidine, and propofol slimes were positive for five, 21, 15, and 18 strains, respectively. The rate of slime productionin glyceryl trinitrate, dexmedetomidine, and propofol containing media were higher than that of the controls.Conclusions: In the light of the results of this study, it is concluded that the drugs and/or additives increase the rate ofslime production. The effects of the preparations administered through catheters on slime production should be investigated,and these effects should be kept in mind during their use. J Microbiol Infect Dis 2012; 2(4: 150-154Key words: Slime Production, Coagulase Negative Staphyloccoci, Parenteral drugs

Antibiotic resistance and biofilm formation among coagulase-negative staphylococci isolated from clinical samples at a tertiary care hospital of eastern Nepal.

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Shrestha, Lok Bahadur; Bhattarai, Narayan Raj; Khanal, Basudha

2017-01-01

Coagulase negative staphylococci were long regarded non-pathogenic as they are the commensals of human skin and mucosa but the recent changes in the medical practice and changes in underlying host populations, they are being considered significant pathogens associated with number of nosocomial infections. The objective of the study was to determine the species, antimicrobial susceptibility pattern, biofilm forming ability of the clinically significant CoNS isolates and to compare the different methods for the detection of biofilm formation. A total of 52 clinically significant CoNS isolates obtained from different units during a year period were studied. Characterization was done using standard microbiological guidelines and antimicrobial susceptibility was done following CLSI guidelines. Biofilm formation was detected by using three methods i.e. tissue culture plate method, congo red agar method and tube adherence method. Among 52 isolates , S. epidermidis (52%) was the most common species which was followed by S. saprophyticus (18%) and S. haemolyticus (14%). Antimicrobial susceptibility pattern of CoNS documented resistance of 80% to ampicillin. Resistance to cefoxitin and ceftriaxone was observed in 58% of the isolates. Biofilm formation was observed in 65.38% of the isolates. The accuracy of Congo red agar and tube adherence method for the detection of biofilm formation was 82% and 76% respectively. CoNS isolates obtained from clinical samples should be processed routinely and antimicrobial susceptibility testing should be performed. Multidrug-resistant CoNS are prevalent. All the three methods i.e. tissue culture plate, Congo red agar and tube adherence method can be used in detecting biofilm formation.

[Oxacillin-resistant coagulase-negative Staphylococci bacteremia at a teaching hospital in Santa Maria, State of Rio Grande do Sul, Brazil].

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Rigatti, Fabiane; Tizotti, Maísa Kraulich; Hörner, Rosmari; Domingues, Vanessa Oliveira; Martini, Rosiéli; Mayer, Letícia Eichstaedt; Khun, Fábio Teixeira; de França, Chirles Araújo; da Costa, Mateus Matiuzzi

2010-01-01

This study aimed to characterize the prevalence and susceptibility profile to oxacillin-resistant Coagulase-negative Staphylococci strains isolated from blood cultures in a teaching hospital, located in Santa Maria, RS. In addition, different methodologies for phenotypic characterization of mecA-mediated oxacillin resistance were compared with genotypic reference testing. After identification (MicroScan - Siemens), the isolates were tested for antimicrobial sensitivity using disk diffusion and automation (MicroScan - Siemens). The presence of mecA gene was identified by the polymerase chain reaction molecular technique. The most common species was Staphylococcus epidermidis (n=40, 67%). The mecA gene was detected in 54 (90%) strains, while analysis of the sensitivity profiles revealed a high rate of resistance to multiple classes of antimicrobial drugs. However, all isolates were uniformly sensitive to vancomycin and tigecycline. The cefoxitin disk was the phenotypic method that best correlated with the gold standard. Analysis of the clinical significance of CoNS isolated from hemocultures and the precise detection of oxacillin resistance represent decisive factors for the correct choice of antibiotic therapy. Although vancomycin constitutes the normal treatment in most Brazilian hospitals, reduction in its use is recommended.

Emerging of coagulase negative staphylococci as a cause of mastitis in dairy animals: An environmental hazard

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Jakeen K. El-Jakee

2013-12-01

Full Text Available In Egypt, knowledge about the coagulase negative staphylococci (CNS involved in mastitic animals is limited. CNS have emerged to be pathogens causing intramammary infections in Egyptian dairy herds. Therefore, the current study was conducted to investigate the occurrence of CNS in dairy ruminants (cattle, buffaloes, sheep and goats. A total of 884 quarter milk samples were investigated to study the prevalence of CNS among mastitic and subclinically mastitic cows, buffalo–cows, ewes and does in Egypt. Identification of the isolates was achieved using API staph test and polymerase chain reaction (PCR. CNS were isolated from the examined subclinical mastitic cattle, buffaloes, sheep and goats with percentages of 16.6%, 59.4%, 50% and 55.6%, respectively. Staphylococcus xylosus, Staphylococcus cohnii, Staphylococcus haemolyticus, Staphylococcus hominis, Staphylococcus saprophyticus, Staphylococcus chromogenes, Staphylococcus lentus, Staphylococcus lugdunensis and Staphylococcus simulans were identified as CNS that recovered from the examined milk samples. The CNS as mastitis-causing agents could not be neglected as they can cause substantial economic losses.

Oxacilin-resistant Coagulase-negative staphylococci (CoNS bacteremia in a general hospital at São Paulo city, Brasil Bacteremias por Staphylococcus coagulase negativos oxacilina resistentes em um hospital na cidade de São Paulo, Brasil

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P.A. D'Azevedo

2008-12-01

Full Text Available In the last decades, coagulase-negative staphylococci (CoNS, especially Staphylococcus epidermidis have become an important cause of bloodstream infections. In addition, rates of methicillin-resistance among CoNS have increased substantially, leading to the use of glicopeptides for therapy. The objective of this study was to evaluate eleven consecutives clinically relevant cases of oxacillin-resistant CoNS bacteremia in a general hospital localized in São Paulo city, Brazil. Five different species were identified by different phenotypic methods, including S. epidermidis (5, S. haemolyticus (3, S. hominis (1, S. warneri (1 and S. cohnii subsp urealyticus (1. A variety of Pulsed Field Gel Electrophoresis profiles was observed by macrorestriction DNA analysis in S. epidermidis isolates, but two of three S. haemolyticus isolates presented the same profile. These data indicated the heterogeneity of the CoNS isolates, suggesting that horizontal dissemination of these microorganisms in the investigated hospital was not frequent. One S. epidermidis and one S. haemolyticus isolates were resistant to teicoplanin and susceptible to vancomycin. The selective pressure due to the use of teicoplanin in this hospital is relevant.Staphylococcus coagulase negativos (SCoN, especialmente Staphylococcus epidermidis tem se tornado causa importante de infecções da corrente circulatória nas últimas décadas. Além disso, percentuais de resistência a meticilina entre os SCoN têm aumentado significativamente, levando ao uso de glicopeptídeos nestes pacientes. O objetivo deste estudo foi avaliar onze casos consecutivos de bacteremia clinicamente relevantes por SCoN oxacilina resistentes em um hospital localizado na cidade de São Paulo, Brasil. Cinco diferentes espécies foram identificadas por diferentes métodos fenotípicos, incluindo S. epidermidis (5, S. haemolyticus (3, S. hominis (1, S. warneri (1 e S. cohnii subsp urealyticus (1. Diferentes perfis

Coagulase-negative staphylococci causing blood stream infection at an Indian tertiary care hospital: Prevalence, antimicrobial resistance and molecular characterisation

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S Singh

2016-01-01

Full Text Available Introduction: Recent years have seen a rise of coagulase-negative staphylococci (CoNS from common contaminants to agents of nosocomial blood stream infections (BSI's. Molecular typing and establishing a correlation with antibiotic resistance is essential particularly in countries like India where genotyping studies for drug-resistant CoNS are sparse. Methods: A prospective study was done over 18 months, wherein 42,693 blood samples were received, and 59 patients with BSI due to CoNS were evaluated. The isolates recovered were identified by a biochemical test panel and matrix-assisted laser desorption ionization – time of flight mass spectrometry followed by antimicrobial susceptibility testing by Kirby–Baur disc diffusion method and E-test strips. Staphylococcal chromosomal cassette mec (SCCmec element was characterised by multiplex polymerase chain reaction for all methicillin-resistant (MR isolates. Results: The majority of CoNS isolated were constituted by Staphylococcus haemolyticus (47.5% followed by Staphylococcus epidermidis (33.9%, Staphylococcus hominis (11.86%, Staphylococcus cohnii (5.08% and Staphylococcus warneri (1.69%. Among all isolates 57.6% were MR with statistically significant higher resistance versus methicillin sensitive-CoNS. This difference was significant for erythromycin (76% vs. 44%, P = 0.011, rifampicin (50% vs. 12%,P= 0.002 and amikacin (26.5% vs. 4%, P = 0.023, ciprofloxacin (64.7% vs. 20%, P = 0.001 and cotrimoxazole (55.9% vs. 20%, P = 0.006. SCCmec type I was predominant (61.8%, P = 0.028 and exhibited multidrug resistance (76.2%. Coexistence of SCCmec type I and III was seen in 8.82% MR isolates. Conclusion: CoNS exhibit high antimicrobial resistance thereby limiting treatment options. The presence of new variants of SCCmec type in hospital-acquired CoNS may predict the antibiotic resistance pattern. This is the first evaluation of the molecular epidemiology of CoNS causing BSI from India and can serve as a

Coagulase-negative staphylococci causing blood stream infection at an Indian tertiary care hospital: Prevalence, antimicrobial resistance and molecular characterisation.

Science.gov (United States)

Singh, S; Dhawan, B; Kapil, A; Kabra, S K; Suri, A; Sreenivas, V; Das, B K

2016-01-01

Recent years have seen a rise of coagulase-negative staphylococci (CoNS) from common contaminants to agents of nosocomial blood stream infections (BSI's). Molecular typing and establishing a correlation with antibiotic resistance is essential particularly in countries like India where genotyping studies for drug-resistant CoNS are sparse. A prospective study was done over 18 months, wherein 42,693 blood samples were received, and 59 patients with BSI due to CoNS were evaluated. The isolates recovered were identified by a biochemical test panel and matrix-assisted laser desorption ionization - time of flight mass spectrometry followed by antimicrobial susceptibility testing by Kirby-Baur disc diffusion method and E-test strips. Staphylococcal chromosomal cassette mec (SCCmec) element was characterised by multiplex polymerase chain reaction for all methicillin-resistant (MR) isolates. The majority of CoNS isolated were constituted by Staphylococcus haemolyticus (47.5%) followed by Staphylococcus epidermidis (33.9%), Staphylococcus hominis (11.86%), Staphylococcus cohnii (5.08%) and Staphylococcus warneri (1.69%). Among all isolates 57.6% were MR with statistically significant higher resistance versus methicillin sensitive-CoNS. This difference was significant for erythromycin (76% vs. 44%, P = 0.011), rifampicin (50% vs. 12%,P= 0.002) and amikacin (26.5% vs. 4%, P = 0.023), ciprofloxacin (64.7% vs. 20%, P = 0.001) and cotrimoxazole (55.9% vs. 20%, P = 0.006). SCCmec type I was predominant (61.8%, P = 0.028) and exhibited multidrug resistance (76.2%). Coexistence of SCCmec type I and III was seen in 8.82% MR isolates. CoNS exhibit high antimicrobial resistance thereby limiting treatment options. The presence of new variants of SCCmec type in hospital-acquired CoNS may predict the antibiotic resistance pattern. This is the first evaluation of the molecular epidemiology of CoNS causing BSI from India and can serve as a guide in the formulation of hospital infection

Antimicrobial susceptibility of coagulase-negative staphylococci isolated from bovine milk samples

NARCIS (Netherlands)

Sampimon, O.C.; Lam, T.G.J.M.; Mevius, D.J.; Schukken, Y.H.; Zadoks, R.N.

2011-01-01

The aim of this study was to examine whether antimicrobial resistance profiles of coagulase-negative Staphylococcus (CNS) species isolated from milk of dairy cows differed between bacterial species, and to compare results obtained by phenotypic and genotypic profiling of resistance to penicillin,

Antibiotic resistance and biofilm formation among coagulase-negative staphylococci isolated from clinical samples at a tertiary care hospital of eastern Nepal

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Lok Bahadur Shrestha

2017-08-01

Full Text Available Abstract Background Coagulase negative staphylococci were long regarded non-pathogenic as they are the commensals of human skin and mucosa but the recent changes in the medical practice and changes in underlying host populations, they are being considered significant pathogens associated with number of nosocomial infections. The objective of the study was to determine the species, antimicrobial susceptibility pattern, biofilm forming ability of the clinically significant CoNS isolates and to compare the different methods for the detection of biofilm formation. Methods A total of 52 clinically significant CoNS isolates obtained from different units during a year period were studied. Characterization was done using standard microbiological guidelines and antimicrobial susceptibility was done following CLSI guidelines. Biofilm formation was detected by using three methods i.e. tissue culture plate method, congo red agar method and tube adherence method. Results Among 52 isolates, S. epidermidis (52% was the most common species which was followed by S. saprophyticus (18% and S. haemolyticus (14%. Antimicrobial susceptibility pattern of CoNS documented resistance of 80% to ampicillin. Resistance to cefoxitin and ceftriaxone was observed in 58% of the isolates. Biofilm formation was observed in 65.38% of the isolates. The accuracy of Congo red agar and tube adherence method for the detection of biofilm formation was 82% and 76% respectively. Conclusion CoNS isolates obtained from clinical samples should be processed routinely and antimicrobial susceptibility testing should be performed. Multidrug-resistant CoNS are prevalent. All the three methods i.e. tissue culture plate, Congo red agar and tube adherence method can be used in detecting biofilm formation.

Coagulase-negative staphylococci: pathogenesis, occurrence of antibiotic resistance genes and in vitro effects of antimicrobial agents on biofilm-growing bacteria.

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Szczuka, Ewa; Jabłońska, Lucyna; Kaznowski, Adam

2016-12-01

Coagulase-negative staphylococci (CoNS) are opportunistic pathogens that particularly cause infections in patients with implanted medical devices. The present research was performed to study the virulence potential of 53 clinical isolates of Staphylococcus capitis, Staphylococcus auricularis, Staphylococcus lugdunensis, Staphylococcus simulans, Staphylococcus cohnii and Staphylococcus caprae. All clinical strains were clonally unrelated. Isolates carried genes encoding resistance to β-lactam (mecA) (15 %), aminoglycoside [aac(6')/aph(2″)(11 %), aph (3')-IIIa (15 %), ant(4')-Ia (19 %)] and macrolide, lincosamide and streptogramin B (MLSB) [erm(A) (4 %), erm(B) (13 %), erm(C) (41 %), msr(A) (11 %)] antibiotics. CoNS isolates (64 %) were able to form biofilms. Confocal laser scanning microscopy revealed that these biofilms formed a three-dimensional structure composed mainly of living cells. All biofilm-positive strains carried the ica operon. In vitro studies demonstrated that a combination treatment with tigecycline and rifampicin was more effective against biofilms than one with ciprofloxacin and rifampicin. The minimum biofilm eradication concentration values were 0.062-0.5 µg ml-1 for tigecycline/rifampicin and 0.250-2 µg ml-1 for ciprofloxacin/rifampicin. All CoNS strains adhered to the human epithelial cell line HeLa, and more than half of the isolates were able to invade the HeLa cells, although most invaded relatively poorly. The virulence of CoNS is also attributed to their cytotoxic effects on HeLa cells. Incubation of HeLa cells with culture supernatant of the CoNS isolates resulted in cell death. The results indicate that the pathogenicity of S. capitis, S. auricularis, S. lugdunensis, S. cohnii and S. caprae is multi-factorial, involving the ability of these bacteria to adhere to human epithelial cells, form biofilms and invade and destroy human cells.

Identification, typing, ecology and epidemiology of coagulase negative staphylococci associated with ruminants.

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Vanderhaeghen, Wannes; Piepers, Sofie; Leroy, Frédéric; Van Coillie, Els; Haesebrouck, Freddy; De Vliegher, Sarne

2015-01-01

Since phenotypic methods to identify coagulase negative staphylococci (CNS) from the milk of ruminants often yield unreliable results, methods for molecular identification based on gene sequencing or fingerprinting techniques have been developed. In addition to culture-based detection of isolates, culture-independent methods may be of interest. On the basis of molecular studies, the five CNS species commonly causing intramammary infections (IMI) are Staphylococcus chromogenes, Staphylococcus epidermidis, Staphylococcus haemolyticus, Staphylococcus simulans and Staphylococcus xylosus. Current knowledge suggests that S. chromogenes is a bovine-adapted species, with most cases of IMI due to this bacterium being opportunistic. S. haemolyticus also appears to be an opportunistic pathogen, but this bacterium occupies a variety of habitats, the importance of which as a source of IMI remains to be elucidated. S. xylosus appears to be a versatile species, but little is known of its epidemiology. S. epidermidis is considered to be a human-adapted species and most cases of IMI appear to arise from human sources, but the organism is capable of residing in other habitats. S. simulans typically causes contagious IMI, but opportunistic cases also occur and the ecology of this bacterium requires further study. Further studies of the ecology and epidemiology of CNS as a cause of IMI in cattle are required, along with careful attention to classification of these bacteria and the diseases they cause. Copyright © 2014 Elsevier Ltd. All rights reserved.

Identification of Variable Traits among the Methicillin Resistant and Sensitive Coagulase Negative Staphylococci in Milk Samples from Mastitic Cows in India

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Sudipta Mahato

2017-07-01

Full Text Available Methicillin resistant Staphylococcus aureus causing bovine mastitis has been very well investigated worldwide. However, there are only limited reports on the characterization of methicillin resistant and sensitive coagulase negative staphylococci (CoNS across the globe. Hence, in the present study, we aim to determine the phenotypic traits based on antimicrobial susceptibility profile and genotypic characterization by verifying the presence of resistance determinants, virulence and toxin genes present in the CoNS causing clinical mastitis. We obtained 62 CoNS isolates from 167 mastitic milk samples collected from three different states of India. The 62 isolates comprises of 10 different CoNS species S. sciuri, S. haemolyticus, S. chromogenes, S. saprophyticus, S. xylosus, S. simulans, S. agnetis, S. epidermidis, S. gallinarum, and S. cohinii. Susceptibility screening against 11 antibiotics determined 45.16% isolates as multidrug resistant (resistant to more than two class of antibiotic, 46.74% resistant (one or two antibiotic class and 8.06% isolates were pan-sensitive (sensitive to all drugs. High resistance was observed against oxacillin and cefoxitin, whereas all isolates were susceptible toward vancomycin and linezolid. Fifty three isolates were methicillin resistant and 9 isolates were sensitive as determined by oxacillin susceptibility assay. The methicillin resistance gene, mecA was found in 95.16% isolates and staphylococcal cassette chromosome mec (SCCmec typing predominantly revealed Type III (n = 34 and Type V (n = 18. Interestingly, 11.9% of mecA positive isolates were oxacillin susceptible and referred as oxacillin susceptible mecA positive staphylococci (OS-MRS. Additionally, genes encoding for enterotoxin, (sea, seb, seh, see toxic shock syndrome (tsst, exfoliatin (eta, etb, etd and virulence (pvl, Y-hlg were also screened. Of all the genes examined, 67.74% of isolate were positive for the Y-hlg gene, followed by the sea gene in

An Activity of Thioacyl Derivatives of 4-Aminoquinolinium Salts towards Biofilm Producing and Planktonic Forms of Coagulase-Negative Staphylococci

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Robert D. Wojtyczka

2015-01-01

Full Text Available Microorganisms present in different environments have developed specific mechanisms of settling on various abiotic and biotic surfaces by forming a biofilm. It seems to be well justified to search for new compounds enabling biofilm reduction, which is highly resistant to antibiotics. This study was thus an initial assessment of the antibacterial activity of two new quinoline derivatives of a structure of 3-thioacyl 1-methyl 4-arylaminoquinolinium salts against coagulase-negative staphylococci (CoNS isolated from a hospital environment, in a form of both biofilms and in planktonic form. Thirty-three stains of CoNS isolated from the hospital environment (air, surfaces and seven reference strains from the ATCC collection were selected for the study. The mean MIC value for 1-methyl-3-benzoylthio-4-(4-chlorophenylaminoquinolinum chloride (4-chlorophenylamino derivative was 42.60 ± 19.91 μg/mL, and in the case of strains subjected to 1-methyl-3-benzoylthio-4-(4-fluorophenylaminoquinolinum chloride (4-fluorophenylamino derivative activity, the mean MIC value was 43.20 ± 14.30 μg/mL. The mean concentration of 4-chlorophenylamino derivative that inhibited biofilm formation was 86.18 ± 30.64 μg/mL. The mean concentration of 4-fluorophenylamino derivatives that inhibited biofilm formation was higher and amounted to 237.09 ± 160.57 μg/mL. Based on the results, both derivatives of the examined compounds exhibit high antimicrobial activity towards strains growing both in planktonic and biofilm form.

Rapid differentiation of Staphylococcus aureus, Staphylococcus epidermidis and other coagulase-negative staphylococci and meticillin susceptibility testing directly from growth-positive blood cultures by multiplex real-time PCR.

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Jukes, Leanne; Mikhail, Jane; Bome-Mannathoko, Naledi; Hadfield, Stephen J; Harris, Llinos G; El-Bouri, Khalid; Davies, Angharad P; Mack, Dietrich

2010-12-01

This study evaluated a multiplex real-time PCR method specific for the mecA, femA-SA and femA-SE genes for rapid identification of Staphylococcus aureus, Staphylococcus epidermidis and non-S. epidermidis coagulase-negative staphylococci (CoNS), and meticillin susceptibility testing directly in positive blood cultures that grew Gram-positive cocci in clusters. A total of 100 positive blood cultures produced: 39 S. aureus [12 meticillin-resistant S. aureus (MRSA), 31% of all the S. aureus]; 30 S. epidermidis (56.6% of the CoNS), 8 Staphylococcus capitis (15.1%), 3 Staphylococcus saprophyticus (5.7%), 4 Staphylococcus hominis (7.5%), 3 Staphylococcus haemolyticus (5.7%), 2 Staphylococcus warneri (3.8%), 1 Staphylococcus cohnii (1.9%) and 2 unidentified Staphylococcus spp. (3.8%); and 1 Micrococcus luteus in pure culture. Two blood cultures had no growth on subculture and five blood cultures grew mixed CoNS. For the 95 blood cultures with pure growth or no growth on subculture, there was very good agreement between real-time PCR and the BD Phoenix identification system for staphylococcal species categorization in S. aureus, S. epidermidis and non-S. epidermidis CoNS and meticillin-resistance determination (Cohen's unweighted kappa coefficient κ=0.882). All MRSA and meticillin-susceptible S. aureus were correctly identified by mecA amplification. PCR amplification of mecA was more sensitive for direct detection of meticillin-resistant CoNS in positive blood cultures than testing with the BD Phoenix system. There were no major errors when identifying staphylococcal isolates and their meticillin susceptibility within 2.5 h. Further studies are needed to evaluate the clinical benefit of using such a rapid test on the consumption of glycopeptide antibiotics and the alteration of empiric therapy in the situation of positive blood cultures growing staphylococci, and the respective clinical outcomes.

Coagulase-negative staphylococci isolated from ocular wound infections after laser refractive surgery: attachment to and accumulation on soft contact lenses.

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Faghri, Jamshid; Razavi, Mohamad Reza

2009-03-01

Disposable soft contact lenses that are commonly used after laser refractive surgery are known to be colonized by bacteria and play a key role in Bacterial Keraitis (BK) pathogenesis. Coagulase-negative staphylococci (CoNS) have been found to be the most common pathogen involved in this postoperative infection. In this study a rapid and a simple assay was developed for studying attachment and accumulation of CoNS on soft contact lenses in vitro using [3H] thymidine. Thirty-five isolates of CoNS were obtained from 27 laser refractive surgery patients. Twenty-five of these thirty-five CoNS were isolated in multiple cultures. Ten CoNS were isolated in cultures from patients who underwent reoperation. The assay was optimized using a biofilm-producing strain, S. epidermidis RP62A, which was subcultured overnight at 37 degrees C on blood agar medium. Quantitative determination of biofilm production was tested. Presence of the genes icaADB and icaD was determined in all isolates. All isolates were biochemically analyzed using the Phene Plate (PhP) system modified for typing of CoNS. The CoNS isolates were further characterized to species level using ID32Staph.Mann-Whitney rank sum test and chi-square test were used to identify statistical differences in adherence, index, antibiotic susceptibility patterns, and biofilm production or presence of the ica operon between clinically significant isolates and non-postoperative BK isolates. No differences in attachment and accumulation were found between isolates causing BK after laser refractive surgery and contaminant isolates. In addition, there were no differences in the distribution of the ica operon between the two groups, as determined by polymerase chain reaction. Nevertheless, the ability to produce biofilm was found to be present significantly more frequently among BK isolates than among non-postoperative BK isolates. This study shows that the method using radioactive thymidine to analyze adherence of CoNS to soft

Epidemiology of coagulase-negative staphylococci intramammary infection in dairy cattle and the effect of bacteriological culture misclassification.

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Dufour, S; Dohoo, I R; Barkema, H W; Descôteaux, L; Devries, T J; Reyher, K K; Roy, J-P; Scholl, D T

2012-06-01

Objectives of this study were to identify the manageable risk factors associated with the lactational incidence, elimination, and prevalence of coagulase-negative staphylococci (CNS) intramammary infections (IMI) while taking into account the difficulties inherent to their diagnosis. A second objective was to evaluate the effect of CNS IMI misclassification in mastitis research. A cohort of 90 Canadian dairy herds was followed throughout 2007 to 2008. In each herd, series of quarter milk samples were collected from a subsample of cows and bacteriological culture was performed to identify prevalent, incident, and eliminated CNS IMI. Practices used on farms were captured using direct observations and a validated questionnaire. The relationships between herd CNS IMI prevalence and herd incidence and elimination rates were explored using linear regression. Manageable risk factors associated with the prevalence, incidence, or elimination of CNS IMI were identified via Bayesian analyses using a latent class model approach, allowing adjustment of the estimates for the imperfect sensitivity and specificity of bacteriological culture. After adjustment for the diagnostic test limitations, a mean CNS IMI quarter prevalence of 42.7% [95% confidence interval (CI): 34.7, 50.1] and incidence and elimination rates of 0.29 new IMI/quarter-month (95% CI: 0.21, 0.37) and 0.79 eliminated IMI/quarter-month (95% CI: 0.66, 0.91), respectively, were observed. Considerable biases of the estimates were observed when CNS IMI misclassification was ignored. These biases were important for measures of association with risk factors, were almost always toward the null value, and led to both type I and type II errors. Coagulase-negative staphylococci IMI incidence appeared to be a stronger determinant of herd IMI prevalence than IMI elimination rate. The majority of herds followed were already using blanket dry cow treatment and postmilking teat disinfection. A holistic approach considering

Prevalence and antibiotic resistance of coagulase-negative Staphylococci isolated from poultry farms in three regions of Ghana.

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Boamah, Vivian Etsiapa; Agyare, Christian; Odoi, Hayford; Adu, Francis; Gbedema, Stephen Yao; Dalsgaard, Anders

2017-01-01

The use of antibiotics in animal production has been associated with the development and spread of antibiotic-resistant organisms including commensals. Coagulase-negative Staphylococcus (CoNS) species, which were until recently considered non-pathogenic, have been associated with opportunistic infections and high resistance to several antibiotics. This study sought to determine the prevalence, identity, and phenotypic resistance of coagulase-negative Staphylococcus spp. isolated from some selected poultry farms and farm workers in the Ashanti, Brong Ahafo, and Greater Accra regions of Ghana. Poultry litter samples and oral swabs of poultry farm workers were collected, from which bacterial species were isolated, identified, and analyzed. Various selective media were used for the presumptive identification of the different species. Confirmation of bacterial identity was done using matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectrometry. Antibiotic susceptibility testing of the isolates was performed using the Kirby-Bauer disk diffusion method. Zones of growth inhibition were interpreted based on the European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines. Two hundred and fifty-six coagulase-negative Staphylococcus spp., comprising S. sciuri (42.97%), S. lentus (35.94%), S. gallinarum (6.64%), S. xylosus (4.30%), S. haemolyticus (3.91%), S. saprophyticus (1.95%), and S. cohnii (0.39%) were confirmed by MALDI-TOF. CoNS were isolated from samples from the Brong Ahafo (48.83%), Ashanti (33.59%), and Greater Accra (17.78%) regions. Isolates from poultry litter constituted 55.47%, and farm workers 44.53%. All the isolates were susceptible to amoxicillin/clavulanic acid and amikacin. The isolates exhibited high resistance toward tetracycline (57.03%), doxycycline (43.75%), and oxacillin (43.36%). Multi-drug resistance (MDR) was observed in 19.14% of the isolates. MDR was higher in isolates obtained from poultry farm

Antimicrobial susceptibility profile and research of mec A and erm genes in coagulase-negative staphylococci isolated from platelet concentrates bags

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Rosiéli Martini

2017-04-01

Full Text Available Abstract In recent years, several studies have described the clinical impact of bacterial infection associated with transfusion of platelet concentrates (PCs. Among the blood components, PCs are responsible for the highest rates of bacterial contamination as well as septic transfusion reactions. We assessed antimicrobial susceptibility profile, resistance to methicillin (MRCoNS, and resistance to macrolides, lincosamides and streptogramins of group B (MLSB of 16 coagulase-negative staphylococci (CoNS isolates from an investigation in 691 PCs bags. We then compared conventional and automated phenotypic methods, disc diffusion test (DD and VITEK(r 2, respectively as well as phenotypic and genotypic methods (Polymerase Chain Reaction - PCR. All CoNS were susceptible to vancomycin. The disc diffusion test characterized 18.75% as MRCoNS and 37.5% with inducible resistance to MLSB (iMLSB, and with VITEK(r 2, 6.3% and 31.25%, respectively. The mecA gene was detected in 18.75% and the erm gene in 31.25% of the isolates. In this study, we found equal percentage values between presence of the mecA gene by PCR and resistance to methicillin using cefoxitin by DD test, evidence of the erm gene by PCR, and iMLSB resistance by automation (VITEK(r 2. Moreover, we identified three strains with beta-lactamase overproduction, and the occurrence of a bigger mistake was verified when automation was compared with DD test. And we observed that D-test was the most reliable for the detection of iMLSB resistance in Staphylococcus sp.

Novel Multiplex PCR Assay for Detection of Chlorhexidine-Quaternary Ammonium, Mupirocin, and Methicillin Resistance Genes, with Simultaneous Discrimination of Staphylococcus aureus from Coagulase-Negative Staphylococci.

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McClure, Jo-Ann; Zaal DeLongchamp, Johanna; Conly, John M; Zhang, Kunyan

2017-06-01

Methicillin-resistant Staphylococcus aureus (MRSA) is a clinically significant pathogen that is resistant to a wide variety of antibiotics and responsible for a large number of nosocomial infections worldwide. The Agency for Healthcare Research and Quality and the Centers for Disease Control and Prevention recently recommended the adoption of universal mupirocin-chlorhexidine decolonization of all admitted intensive care unit patients rather than MRSA screening with targeted treatments, which raises a serious concern about the selection of resistance to mupirocin and chlorhexidine in strains of staphylococci. Thus, a simple, rapid, and reliable approach is paramount in monitoring the prevalence of resistance to these agents. We developed a simple multiplex PCR assay capable of screening Staphylococcus isolates for the presence of antiseptic resistance genes for chlorhexidine and quaternary ammonium compounds, as well as mupirocin and methicillin resistance genes, while simultaneously discriminating S. aureus from coagulase-negative staphylococci (CoNS). The assay incorporates 7 PCR targets, including the Staphylococcus 16S rRNA gene (specifically detecting Staphylococcus spp.), nuc (distinguishing S. aureus from CoNS), mecA (distinguishing MRSA from methicillin-susceptible S. aureus ), mupA and mupB (identifying high-level mupirocin resistance), and qac and smr (identifying chlorhexidine and quaternary ammonium resistance). Our assay demonstrated 100% sensitivity, specificity, and accuracy in a total of 23 variant antiseptic- and/or antibiotic-resistant control strains. Further validation of our assay using 378 randomly selected and previously well-characterized local clinical isolates confirmed its feasibility and practicality. This may prove to be a useful tool for multidrug-resistant Staphylococcus monitoring in clinical laboratories, particularly in the wake of increased chlorhexidine and mupirocin treatments. Copyright © 2017 American Society for Microbiology.

Detection of Staphylococcus aureus among coagulase positive staphylococci from animal origin based on conventional and molecular methods

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Nikolina Velizarova Rusenova

2017-03-01

Full Text Available The present study aimed to detect Staphylococcus aureus (S. aureus among other coagulase positive staphylococci from animal origin by using conventional methods (biochemical tests and latex agglutination and a molecular method, based on the nuc gene, as the gold standard and to assess the usefulness of these methods. For this purpose, total of 344 staphylococcal isolates were collected and analysed. A total of 156 isolates suspicious for S. aureus were detected by a conventional biochemical method – 88 from cows, 18 from goats, 7 from pigs, 17 from poultry, 7 from rabbits and 19 from dogs. The majority of S. aureus strains gave typical biochemical reactions with the exception of 30 (19.2% and 25 (16% that were VP negative and weak positive in fermenting mannitol, respectively. Twelve strains were found to be non-haemolytic (7.7% and four strains did not ferment trehalose (2.6%. Other staphylococci were identified as S. pseudintermedius (n = 103, S. hyicus (n = 23 and the rest were coagulase-negative staphylococci. Latex agglutination test resulted in rapid positive reactions with S. aureus with exception of 5 strains (3.2% from cow mastitis milk. Positive agglutination reactions were also established with S. pseudintermedius, and S. hyicus. PCR confirmed all strains that were preliminary identified as S. aureus by amplification of 270 bp fragment of nuc gene specific for this species. The atypical reactions in certain strains established in this study have shown that the precise detection of S. aureus from animal origin should be done by combination of conventional and molecular methods.

Characterization and Technological Features of Autochthonous Coagulase-Negative Staphylococci as Potential Starters for Portuguese Dry Fermented Sausages.

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Semedo-Lemsaddek, Teresa; Carvalho, Laura; Tempera, Carolina; Fernandes, Maria H; Fernandes, Maria J; Elias, Miguel; Barreto, António S; Fraqueza, Maria J

2016-05-01

The manufacture of dry fermented sausages is an important part of the meat industry in Southern European countries. These products are usually produced in small shops from a mixture of pork, fat, salt, and condiments and are stuffed into natural casings. Meat sausages are slowly cured through spontaneous fermentation by autochthonous microbiota present in the raw materials or introduced during manufacturing. The aim of this work was to evaluate the technological and safety features of coagulase-negative staphylococci (CNS) isolated from Portuguese dry fermented meat sausages in order to select autochthonous starters. Isolates (n = 104) obtained from 2 small manufacturers were identified as Staphylococcus xylosus, Staphylococcus equorum, Staphylococcus saprophyticus, and Staphylococcus carnosus. Genomically diverse isolates (n = 82) were selected for further analysis to determine the ability to produce enzymes (for example, nitrate-reductases, proteases, lipases) and antibiotic susceptibility. Autochthonous CNS producing a wide range of enzymes and showing low antibioresistance were selected as potential starters for future use in the production of dry fermented meat sausages. © 2016 Institute of Food Technologists®

Increasing Resistance of Coagulase-Negative Staphylococci in Total Hip Arthroplasty Infections: 278 THA-Revisions due to Infection Reported to the Norwegian Arthroplasty Register from 1993 to 2007

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Olav Lutro

2014-01-01

Full Text Available We investigated bacterial findings from intraoperative tissue samples taken during revision due to infection after total hip arthroplasty (THA. The aim was to investigate whether the susceptibility patterns changed during the period from 1993 through 2007. Reported revisions due to infection in the Norwegian Arthroplasty Register (NAR were identified, and 10 representative hospitals in Norway were visited. All relevant information on patients reported to the NAR for a revision due to infection, including bacteriological findings, was collected from the medical records. A total of 278 revision surgeries with bacterial growth in more than 2 samples were identified and included. Differences between three 5-year time periods were tested by the chi-square test for linear trend. The most frequent isolates were coagulase-negative staphylococci (CoNS (41%, 113/278 and Staphylococcus aureus (19%, 53/278. The proportion of CoNS resistant to the methicillin-group increased from 57% (16/28 in the first period, 1993–1997, to 84% (52/62 in the last period, 2003–2007 (P = 0.003. There was also significant increase in resistance for CoNS to cotrimoxazole, quinolones, clindamycin, and macrolides. All S. aureus isolates were sensitive to both the methicillin-group and the aminoglycosides. For the other bacteria identified no changes in susceptibility patterns were found.

Antimicrobial susceptibility of coagulase-positive and coagulase-variable Staphylococci from various indications of swine, dogs and cats as determined in the BfT-GermVet monitoring program 2004-2006.

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Schwarz, Stefan; Alesík, Eva; Werckenthin, Christiane; Grobbel, Mirjam; Lübke-Becker, Antina; Wieler, Lothar H; Wallmann, Jürgen

2007-01-01

A total of 248 coagulase-positive and coagulase-variable staphylococci from two indications of swine (infections of the urinary/genital tract including strains from the mastitis metritis agalactia syndrome as well as infections of the skin) as well as two indications of dogs/cats (respiratory tract infections and infections of skin/ear/mouth) were investigated for their susceptibility to numerous antimicrobial agents. Regardless of the animal origin and indication, the most frequently detected resistance properties were resistances against penicillin G (53-77%) and ampicillin (42-75%), tetracycline (33-52%) as well as erythromycin (13-27%). Oxacillin-resistant staphylococci were rarely detected.

Licheniocin 50.2 and Bacteriocins from Lactococcus lactis subsp. lactis biovar. diacetylactis BGBU1-4 Inhibit Biofilms of Coagulase Negative Staphylococci and Listeria monocytogenes Clinical Isolates.

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Cirkovic, Ivana; Bozic, Dragana D; Draganic, Veselin; Lozo, Jelena; Beric, Tanja; Kojic, Milan; Arsic, Biljana; Garalejic, Eliana; Djukic, Slobodanka; Stankovic, Slavisa

2016-01-01

Coagulase negative staphylococci (CoNS) and Listeria monocytogenes have important roles in pathogenesis of various genital tract infections and fatal foetomaternal infections, respectively. The aim of our study was to investigate the inhibitory effects of two novel bacteriocins on biofilms of CoNS and L. monocytogenes genital isolates. The effects of licheniocin 50.2 from Bacillus licheniformis VPS50.2 and crude extract of bacteriocins produced by Lactococcus lactis subsp. lactis biovar. diacetylactis BGBU1-4 (BGBU1-4 crude extract) were evaluated on biofilm formation and formed biofilms of eight CoNS (four S. epidermidis, two S. hominis, one S. lugdunensis and one S. haemolyticus) and 12 L. monocytogenes genital isolates. Licheniocin 50.2 and BGBU1-4 crude extract inhibited the growth of both CoNS and L. monocytogenes isolates, with MIC values in the range between 200-400 AU/ml for licheniocin 50.2 and 400-3200 AU/ml for BGBU1-4 crude extract. Subinhibitory concentrations (1/2 × and 1/4 × MIC) of licheniocin 50.2 inhibited biofilm formation by all CoNS isolates (p < 0.05, respectively), while BGBU1-4 crude extract inhibited biofilm formation by all L. monocytogenes isolates (p < 0.01 and p < 0.05, respectively). Both bacteriocins in concentrations of 100 AU/mL and 200 AU/mL reduced the amount of 24 h old CoNS and L. monocytogenes biofilms (p < 0.05, p < 0.01, p < 0.001). This study suggests that novel bacteriocins have potential to be used for genital application, to prevent biofilm formation and/or to eradicate formed biofilms, and consequently reduce genital and neonatal infections by CoNS and L. monocytogenes.

Prevalence of coagulase-positive staphylococci, other than Staphylococcus aureus, in bovine mastitis.

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Roberson, J R; Fox, L K; Hancock, D D; Gay, J M; Besser, T E

1996-01-01

To determine prevalence and relevance of coagulase-positive Staphylococcus hyicus and S intermedius intramammary infections (IMI) in dairy cows and determine the ability of the 4-hour tube coagulase (TC) test to differentiate the coagulase-positive staphylococci (CPS). Prevalence of CPS was determined for primiparous cows (point prevalence and prevalence at first parturition) and multiparous cows (point prevalence) of 2 herd groups: 10% CPS IMI prevalence = high prevalence (HP). For prevalence, cows of 22 dairy herds. For TC, 1,038 CPS strains isolated from cow milk. Speciation of CPS from aseptically collected composite milk samples was performed. Coagulase-positive isolates from 4 cow groups were tested for their ability to coagulate rabbit plasma by 4 hours: LP and HP primiparous cows at parturition, and LP and HP cows any time after first parturition. Of 487 CPS in the prevalence study, 82.1% were S aureus, 17.7% were coagulase-positive S hyicus, and 0.2% were S intermedius. Of all CPS IMI in LP herds, 34% were coagulase-positive S hyicus; of all CPS IMI in HP herds, 9% were coagulase-positive S hyicus. Coagulase-positive S hyicus appeared to persist to the end of lactation in 4 cows (mean linear somatic cell count = 3.7). The TC test was > or = 97% sensitive, < or = 33% specific, and had a predictive value positive range of 60 to 97% for S aureus isolates. Coagulase-positive S hyicus appears capable of inducing chronic, low-grade IMI. Staphylococcus intermedius does not appear to be an important mastitis pathogen. The TC test is not valid to use as the sole method to differentiate CPS species.

Comparative antibiogram of coagulase-negative Staphylococci (CNS) associated with subclinical and clinical mastitis in dairy cows.

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Bansal, B K; Gupta, D K; Shafi, T A; Sharma, S

2015-03-01

The present study was planned to determine the in vitro antibiotic susceptibility of coagulase-negative Staphylococci (CNS) strains isolated from clinical and subclinical cases of mastitis in dairy cows. Antibiotic sensitivity profile will be helpful to recommend early therapy at the field level prior to availability of CST results. The milk samples from cases of clinical mastitis received in Mastitis Laboratory, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana and those of subclinical mastitis collected during routine screening of state dairy farms, were subjected to microbial culture. Identification of CNS organisms was done by standard biochemical tests. Antibiotic sensitivity testing, based on 30 antibiotics belonging to 12 groups, was done on 58 randomly selected CNS isolates (clinical isolates: 41, subclinical isolates: 17). Isolates were highly susceptible to chloramphenicol (98.3%), gentamicin (93.1%), streptomycin (91.4%), linezolid (91.4%), ceftixozime (87.9%), cloxacillin (86.2%), clotrimazole (86.2%), bacitracin (86.2%), enrofloxacin (84.5%) and ceftrioxone + tazobactum (70.7%), while resistance was observed against amoxicillin (77.6%), penicillin (75.9%), ampicillin (74.1%) and cefoperazone (51.7%). Overall, isolates from clinical cases of mastitis had a higher resistance than subclinical isolates. CNS isolates were susceptible to chloramphenicol, gentamicin and streptomycin, while higher resistance was recorded against routinely used penicillin group.

Significance of coagulase negative Staphylococcus from blood cultures: persisting problems and partial progress in resource constrained settings.

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Sidhu, Shailpreet K; Malhotra, Sita; Devi, Pushpa; Tuli, Arpandeep K

2016-12-01

Coagulase negative Staphylococcus (CoNS) is frequently isolated from blood cultures but their significance is difficult to interpret. CoNS bacteria which are often previously dismissed as culture contaminants are attracting greater importance as true pathogens in the past decades. Clinical evaluation of these isolates suggests that although there is a relative increase of CoNS associated bloodstream infections in recent years, the microorganisms still remain the most common contaminants in blood cultures. The objective of this study was to determine the significance of CoNS isolated from blood cultures. A retrospective study was conducted to evaluate the rate of contamination in blood cultures in a tertiary care hospital. The paired specimens of blood were cultured using conventional culture methods and the isolates of coagulase negative staphylococci were identified by standard methodology. Clinical data, laboratory indices, microbiological parameters and patient characteristics were analyzed. Of 3503 blood samples, CoNS were isolated from blood culture of 307 patients (8.76%). The isolates were reported as true pathogens of bloodstream infections in only 74 out of 307 cases (24.1%). In the vast majority, 212 of 307 (69.0%), they were mere blood culture contaminants and reported as insignificant/contaminant. Determining whether a growth in the blood culture is a pathogen or a contaminant is a critical issue and multiple parameters have to be considered before arriving at a conclusion. Ideally, the molecular approach is for the most part a consistent method in determining the significant isolates of CoNS. However, in countries with inadequate resources, species identification and antibiogram tests are recommended when determining significance of these isolates.

Prevalence and antibiotic resistance of coagulase-negative Staphylococci isolated from poultry farms in three regions of Ghana

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Boamah VE

2017-06-01

Full Text Available Vivian Etsiapa Boamah,1 Christian Agyare,1 Hayford Odoi,1 Francis Adu,1 Stephen Yao Gbedema,1 Anders Dalsgaard2 1Microbiology Section, Department of Pharmaceutics, Faculty of Pharmacy and Pharmaceutical Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana; 2Section of Food Safety and Zoonoses, Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederisksberg, Denmark Abstract: The use of antibiotics in animal production has been associated with the development and spread of antibiotic-resistant organisms including commensals. Coagulase-negative Staphylococcus (CoNS species, which were until recently considered non-pathogenic, have been associated with opportunistic infections and high resistance to several antibiotics. This study sought to determine the prevalence, identity, and phenotypic resistance of coagulase-negative Staphylococcus spp. isolated from some selected poultry farms and farm workers in the Ashanti, Brong Ahafo, and Greater Accra regions of Ghana. Poultry litter samples and oral swabs of poultry farm workers were collected, from which bacterial species were isolated, identified, and analyzed. Various selective media were used for the presumptive identification of the different species. Confirmation of bacterial identity was done using matrix-assisted laser desorption/ionization time of flight (MALDI-TOF mass spectrometry. Antibiotic susceptibility testing of the isolates was performed using the Kirby-Bauer disk diffusion method. Zones of growth inhibition were interpreted based on the European Committee on Antimicrobial Susceptibility Testing (EUCAST guidelines. Two hundred and fifty-six coagulase-negative Staphylococcus spp., comprising S. sciuri (42.97%, S. lentus (35.94%, S. gallinarum (6.64%, S. xylosus (4.30%, S. haemolyticus (3.91%, S. saprophyticus (1.95%, and S. cohnii (0.39% were confirmed by MALDI-TOF. CoNS were isolated from samples

Comparative assessment of antibiotic susceptibility of coagulase-negative staphylococci in biofilm versus planktonic culture as assessed by bacterial enumeration or rapid XTT colorimetry.

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Cerca, Nuno; Martins, Silvia; Cerca, Filipe; Jefferson, Kimberly K; Pier, Gerald B; Oliveira, Rosário; Azeredo, Joana

2005-08-01

To quantitatively compare the antibiotic susceptibility of biofilms formed by the coagulase-negative staphylococci (CoNS) Staphylococcus epidermidis and Staphylococcus haemolyticus with the susceptibility of planktonic cultures. Several CoNS strains were grown planktonically or as biofilms to determine the effect of the mode of growth on the level of susceptibility to antibiotics with different mechanisms of action. The utility of a new, rapid colorimetric method that is based on the reduction of a tetrazolium salt (XTT) to measure cell viability was tested by comparison with standard bacterial enumeration techniques. A 6 h kinetic study was performed using dicloxacillin, cefazolin, vancomycin, tetracycline and rifampicin at the peak serum concentration of each antibiotic. In planktonic cells, inhibitors of cell wall synthesis were highly effective over a 3 h period. Biofilms were much less susceptible than planktonic cultures to all antibiotics tested, particularly inhibitors of cell wall synthesis. The susceptibility to inhibitors of protein and RNA synthesis was affected by the biofilm phenotype to a lesser degree. Standard bacterial enumeration techniques and the XTT method produced equivalent results both in biofilms and planktonic assays. This study provides a more accurate comparison between the antibiotic susceptibilities of planktonic versus biofilm populations, because the cell densities in the two populations were similar and because we measured the concentration required to inhibit bacterial metabolism rather than to eradicate the entire bacterial population. While the biofilm phenotype is highly resistant to antibiotics that target cell wall synthesis, it is fairly susceptible to antibiotics that target RNA and protein synthesis.

Sepsis due to linezolid resistant Staphylococcus cohnii and Staphylococcus kloosii: first reports of linezolid resistance in coagulase negative staphylococci from India.

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Peer, M A; Nasir, R A; Kakru, D K; Fomda, B A; Bashir, G; Sheikh, I A

2011-01-01

Linezolid, a viable alternative to vancomycin against methicillin resistant staphylococcal isolates, has been in use for a decade around the globe. However, resistance against staphylococci remains extremely rare and unreported from most of the Asian countries. Herein, we report two cases of linezolid resistant, coagulase negative staphylococcal sepsis for the first time from India. The first case was an 18-year-old burn patient, who, after a major graft surgery, landed in sepsis, and linezolid resistant Staphylococcus cohnii with an minimum inhibitory concentration (MIC) of >256 μg/ml by both broth microdilution and Etest, was isolated from multiple blood cultures. The second patient was a 60-year-old male with an intracranial bleed and sepsis, from whose blood cultures, linezolid resistant Staphylococcus kloosii was repeatedly isolated. Linezolid MIC was >32 μg/ml by broth microdilution and >16 μg/ml by Etest.

Sepsis due to linezolid resistant Staphylococcus cohnii and Staphylococcus kloosii: First reports of linezolid resistance in coagulase negative staphylococci from India

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M A Peer

2011-01-01

Full Text Available Linezolid, a viable alternative to vancomycin against methicillin resistant staphylococcal isolates, has been in use for a decade around the globe. However, resistance against staphylococci remains extremely rare and unreported from most of the Asian countries. Herein, we report two cases of linezolid resistant, coagulase negative staphylococcal sepsis for the first time from India. The first case was an 18-year-old burn patient, who, after a major graft surgery, landed in sepsis, and linezolid resistant Staphylococcus cohnii with an minimum inhibitory concentration (MIC of >256 μg/ml by both broth microdilution and Etest, was isolated from multiple blood cultures. The second patient was a 60-year-old male with an intracranial bleed and sepsis, from whose blood cultures, linezolid resistant Staphylococcus kloosii was repeatedly isolated. Linezolid MIC was >32 μg/ml by broth microdilution and >16 μg/ml by Etest.

Antibiotic resistance and mecA characterization of coagulase-negative staphylococci isolated from three hotels in London, UK

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Zhen eXu

2015-09-01

Full Text Available Antibiotic resistance in bacteria isolated from non–healthcare environments, is a potential problem to public health. In our survey a total of 71 coagulase negative staphylococci belonging to 11 different species were isolated from 3 large hotels in London, UK. The most prevalent species was Staphylococcus haemolyticus, with S. hominis, S. warneri, S.cohnii and S. epidermidis commonly detected. Antimicrobial susceptibilities and carriage of the mecA gene were determined for all of these isolates. Most (85.9% staphylococci were resistant to multiple antibiotics with all displaying increased susceptibility towards penicillin, fusidic acid, erythromycin and cefepime. 21 (29.5% of the isolates were mecA positive, however MIC values to oxacillin, normally associated with the carriage of mecA, varied widely in this group (from 0.06 mg/L to 256 mg/L. 15 of the 21 mecA positive isolates carried SCCmec of these 7 were type V, 1 type I, 1 type II and 1 type IV. Additionally, five of these 15 isolates carried a previously unreported type, 1A, which involves an association between class A mec complex and ccr type 1. The remaining 6 of the 21 isolates were non-typeable and carried a combination of class A mec complex and ccrC. In addition to this, we also report on new MLST types which were assigned for 5 Staphylococcus epidermidis isolates. 4 out of these 5 isolates had MICs between 0.06 to 256 mg/L to oxacillin and would be regarded as clinically susceptible but one isolate had a high oxacillin MIC of 256 mg/L. We demonstrated widespread multiple drug resistance among different staphylococcal species isolated from non-healthcare environments highlighting the potential for these species to act as a reservoir for methicillin and other forms of drug resistance.

Antibiotic resistance and mecA characterization of coagulase-negative staphylococci isolated from three hotels in London, UK.

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Xu, Zhen; Mkrtchyan, Hermine V; Cutler, Ronald R

2015-01-01

Antibiotic resistance in bacteria isolated from non-healthcare environments, is a potential problem to public health. In our survey a total of 71 coagulase negative staphylococci (CNS) belonging to 11 different species were isolated from three large hotels in London, UK. The most prevalent species was Staphylococcus haemolyticus, with S. hominis, S. warneri, S. cohnii, and Staphylococcus epidermidis commonly detected. Antimicrobial susceptibilities and carriage of the mecA gene were determined for all of these isolates. Most (85.9%) staphylococci were resistant to multiple antibiotics with all displaying increased susceptibility toward penicillin, fusidic acid, erythromycin, and cefepime. Twenty-one (29.5%) of the isolates were mecA positive, however MIC values to oxacillin, normally associated with the carriage of mecA, varied widely in this group (from 0.06 to 256 mg/L). Fifteen of the twenty-one mecA positive isolates carried SCCmec of these seven were type V, one type I, one type II, and one type IV. Additionally, five of these 15 isolates carried a previously unreported type, 1A, which involves an association between class A mec complex and ccr type 1. The remaining six of the 21 isolates were non-typeable and carried a combination of class A mec complex and ccrC. In addition to this, we also report on new MLST types which were assigned for five S. epidermidis isolates. Four out of these five isolates had MICs between 0.06 and 256 mg/L to oxacillin and would be regarded as clinically susceptible but one isolate had a high oxacillin MIC of 256 mg/L. We demonstrated widespread multiple drug resistance among different staphylococcal species isolated from non-healthcare environments highlighting the potential for these species to act as a reservoir for methicillin and other forms of drug resistance.

Comparative antibiogram of coagulase-negative Staphylococci (CNS associated with subclinical and clinical mastitis in dairy cows

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B. K. Bansal

2015-03-01

Full Text Available Aim: The present study was planned to determine the in vitro antibiotic susceptibility of coagulase-negative Staphylococci (CNS strains isolated from clinical and subclinical cases of mastitis in dairy cows. Antibiotic sensitivity profile will be helpful to recommend early therapy at the field level prior to availability of CST results. Materials and Methods: The milk samples from cases of clinical mastitis received in Mastitis Laboratory, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana and those of subclinical mastitis collected during routine screening of state dairy farms, were subjected to microbial culture. Identification of CNS organisms was done by standard biochemical tests. Antibiotic sensitivity testing, based on 30 antibiotics belonging to 12 groups, was done on 58 randomly selected CNS isolates (clinical isolates: 41, subclinical isolates: 17. Results: Isolates were highly susceptible to chloramphenicol (98.3%, gentamicin (93.1%, streptomycin (91.4%, linezolid (91.4%, ceftixozime (87.9%, cloxacillin (86.2%, clotrimazole (86.2%, bacitracin (86.2%, enrofloxacin (84.5% and ceftrioxone + tazobactum (70.7%, while resistance was observed against amoxicillin (77.6%, penicillin (75.9%, ampicillin (74.1% and cefoperazone (51.7%. Overall, isolates from clinical cases of mastitis had a higher resistance than subclinical isolates. Conclusion: CNS isolates were susceptible to chloramphenicol, gentamicin and streptomycin, while higher resistance was recorded against routinely used penicillin group.

First identification of methicillin-resistant Staphylococcus pseudintermedius strains among coagulase-positive staphylococci isolated from dogs with otitis externa in Trinidad, West Indies

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Francis Dziva

2015-12-01

Full Text Available Background: Otitis externa is a common inflammatory ear disease in dogs caused by a variety of pathogens, and coagulase-positive staphylococci are frequently isolated from such infections. Objective: To identify antimicrobial susceptibility profiles and methicillin-resistant strains among coagulase-positive staphylococci isolated from otitis externa in dogs. Methods: A cross-sectional study was performed over 2 years on 114 client-owned dogs presented to the Veterinary Teaching Hospital with a primary complaint of ear infections. Swabs were obtained from both ears and cultured for staphylococci which were subsequently confirmed as coagulase-positive using rabbit plasma. Antimicrobial susceptibility assays were assessed on all isolates followed by subsequent genetic analysis for species identification and detection of the mecA gene. Results: Sixty-five coagulase-positive staphylococci were isolated from 114 client-owned dogs. The isolates exhibited resistance against neomycin (58.5%, streptomycin (49.2%, penicillin (49.2%, polymyxin B (44.6%, tetracycline (36.9%, sulphamethoxazole/trimethoprim (33.8%, kanamycin (33.8%, doxycycline (32.3%, norfloxacin (23.1%, amoxicillin/clavulanate (20%, ciprofloxacin (20%, enrofloxacin (18.5%, gentamicin (16.9%, and cephalothin (9.2%. Forty (61.5% of the isolates were resistant to at least three or more antimicrobials and 10 were sensitive to all. Using a multiplex polymerase chain reaction assay based on species-specific regions of the thermonuclease (nuc gene, 38/65 (58.5% isolates were classified as Staphylococcus aureus, 23/65 (35.4% as S. pseudintermedius, 2/65 (3.1% as S. intermedius, and 2/65 (3.1% as S. schleiferi. Analysis for the mecA gene revealed two positive isolates of S. pseudintermedius which were oxacillin-resistant, representing a first report of such organisms in the Caribbean. Conclusion: Despite the relatively high prevalence of multidrug-resistant coagulase-positive staphylococci in

Antibiotic Susceptibility of Coagulase-Negative Staphylococci Isolated from Bovine Subclinical Mastitis in Turkey

OpenAIRE

Beytullah Kenar*, Yahya Kuyucuoğlu and Esra Şeker

2012-01-01

A total of 572 California Mastitis Test (CMT) positive milk samples were collected from 423 lactating cows on 18 private farms in the Middle Western Anatolia. Coagulase–negative staphylococci colonies and CNS species identification was performed based on conventional biochemical techniques and using the API Staph test. Slime production was detected by Congo Red Agar (CRA) method. The antibiotic susceptibility was determined according to the National Committee for Clinical Laboratory Standards...

The Staphylococci Phages Family: An Overview

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Laurence Van Melderen

2012-11-01

Full Text Available Due to their crucial role in pathogenesis and virulence, phages of Staphylococcus aureus have been extensively studied. Most of them encode and disseminate potent staphylococcal virulence factors. In addition, their movements contribute to the extraordinary versatility and adaptability of this prominent pathogen by improving genome plasticity. In addition to S. aureus, phages from coagulase-negative Staphylococci (CoNS are gaining increasing interest. Some of these species, such as S. epidermidis, cause nosocomial infections and are therefore problematic for public health. This review provides an overview of the staphylococcal phages family extended to CoNS phages. At the morphological level, all these phages characterized so far belong to the Caudovirales order and are mainly temperate Siphoviridae. At the molecular level, comparative genomics revealed an extensive mosaicism, with genes organized into functional modules that are frequently exchanged between phages. Evolutionary relationships within this family, as well as with other families, have been highlighted. All these aspects are of crucial importance for our understanding of evolution and emergence of pathogens among bacterial species such as Staphylococci.

Antibiotic exposure in a low-income country: screening urine samples for presence of antibiotics and antibiotic resistance in coagulase negative staphylococcal contaminants.

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Anne Mette Lerbech

Full Text Available Development of antimicrobial resistance has been assigned to excess and misuse of antimicrobial agents. Staphylococci are part of the normal flora but are also potential pathogens that have become essentially resistant to many known antibiotics. Resistances in coagulase negative staphylococci (CoNS are suggested to evolve due to positive selective pressure following antibiotic treatment. This study investigated the presence of the nine most commonly used antimicrobial agents in human urine from outpatients in two hospitals in Ghana in relation to CoNS resistance. Urine and CoNS were sampled (n = 246 and n = 96 respectively from patients in two hospitals in Ghana. CoNS were identified using Gram staining, coagulase test, and MALDI-TOF/MS, and the antimicrobial susceptibility to 12 commonly used antimicrobials was determined by disk diffusion. Moreover an analytical method was developed for the determination of the nine most commonly used antimicrobial agents in Ghana by using solid-phase extraction in combination with HPLC-MS/MS using electron spray ionization. The highest frequency of resistance to CoNS was observed for penicillin V (98%, trimethoprim (67%, and tetracycline (63%. S. haemolyticus was the most common isolate (75%, followed by S. epidermidis (13% and S. hominis (6%. S. haemolyticus was also the species displaying the highest resistance prevalence (82%. 69% of the isolated CoNS were multiple drug resistant (≧ 4 antibiotics and 45% of the CoNS were methicillin resistant. Antimicrobial agents were detected in 64% of the analysed urine samples (n = 121 where the most frequently detected antimicrobials were ciprofloxacin (30%, trimethoprim (27%, and metronidazole (17%. The major findings of this study was that the prevalence of detected antimicrobials in urine was more frequent than the use reported by the patients and the prevalence of resistant S. haemolyticus was more frequent than other resistant CoNS species when antimicrobial

Acceleration of the direct identification of Staphylococcus aureus versus coagulase-negative staphylococci from blood culture material: a comparison of six bacterial DNA extraction methods.

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Loonen, A J M; Jansz, A R; Kreeftenberg, H; Bruggeman, C A; Wolffs, P F G; van den Brule, A J C

2011-03-01

To accelerate differentiation between Staphylococcus aureus and coagulase-negative staphylococci (CNS), this study aimed to compare six different DNA extraction methods from two commonly used blood culture materials, i.e. BACTEC and BacT/ALERT. Furthermore, we analysed the effect of reduced blood culture incubation for the detection of staphylococci directly from blood culture material. A real-time polymerase chain reaction (PCR) duplex assay was used to compare the six different DNA isolation protocols on two different blood culture systems. Negative blood culture material was spiked with methicillin-resistant S. aureus (MRSA). Bacterial DNA was isolated with automated extractor easyMAG (three protocols), automated extractor MagNA Pure LC (LC Microbiology Kit M(Grade)), a manual kit MolYsis Plus and a combination of MolYsis Plus and the easyMAG. The most optimal isolation method was used to evaluate reduced bacterial incubation times. Bacterial DNA isolation with the MolYsis Plus kit in combination with the specific B protocol on the easyMAG resulted in the most sensitive detection of S. aureus, with a detection limit of 10 CFU/ml, in BacT/ALERT material, whereas using BACTEC resulted in a detection limit of 100 CFU/ml. An initial S. aureus or CNS load of 1 CFU/ml blood can be detected after 5 h of incubation in BacT/ALERT 3D by combining the sensitive isolation method and the tuf LightCycler assay.

Clinical and molecular features of methicillin-resistant, coagulase-negative staphylococci of pets and horses.

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Kern, Andrea; Perreten, Vincent

2013-06-01

To determine the antibiotic resistance and fingerprint profiles of methicillin-resistant coagulase-negative staphylococci (MRCoNS) from animal infections among different practices and examine the history of antibiotic treatment. Isolates were identified by mass spectrometry and tested for antimicrobial resistance by broth dilution, microarrays and sequence analysis of the topoisomerases. Diversity was assessed by PFGE, icaA PCR and staphylococcal cassette chromosome mec (SCCmec), arginine catabolic mobile element (ACME) and multilocus sequence typing. Clinical records were examined retrospectively. MRCoNS were identified as Staphylococcus epidermidis (n=20), Staphylococcus haemolyticus (n=17), Staphylococcus hominis (n=3), Staphylococcus capitis (n=1), Staphylococcus cohnii (n=1) and Staphylococcus warneri (n=1). PFGE identified one clonal lineage in S. hominis isolates and several in S. haemolyticus and S. epidermidis. Fourteen sequence types were identified in S. epidermidis, with sequence type 2 (ST2) and ST5 being predominant. Ten isolates contained SCCmec IV, seven contained SCCmec V and the others were non-typeable. ACMEs were detected in 11 S. epidermidis isolates. One S. hominis and 10 S. epidermidis isolates were icaA positive. In addition to mecA-mediated β-lactam resistance, the most frequent resistance was to gentamicin/kanamycin [aac(6')-Ie-aph(2')-Ia, aph(3')-III] (n=34), macrolides/lincosamides [erm(C), erm(A), msr, lnu(A)] (n=31), tetracycline [tet(K)] (n=22), streptomycin [str, ant(6)-Ia] (n=20), trimethoprim [dfr(A), dfr(G)] (n=17), sulfamethoxazole (n = 34) and fluoroquinolones [amino acid substitutions in GyrA and GrlA] (n=30). Clinical data suggest selection through multiple antibiotic courses and emphasize the importance of accurate diagnosis and antibiograms. MRCoNS from animal infection sites are genetically heterogeneous multidrug-resistant strains that represent a new challenge in the prevention and therapy of infections in veterinary

cfr-mediated linezolid-resistant clinical isolates of methicillin-resistant coagulase-negative staphylococci from China.

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Song, Yunjia; Lv, Yuan; Cui, Lanqing; Li, Yun; Ke, Qian; Zhao, Yixuan

2017-03-01

Three linezolid-resistant coagulase-negative staphylococci (LR-CoNS), including two Staphylococcus cohnii and one Staphylococcus capitis, were isolated from 1104 clinical staphylococcal isolates across China in 2013-2014. Antibiotic susceptibilities of the bacteria were determined by the agar dilution method. PCR and DNA sequencing were performed to determine the potential molecular mechanism of linezolid resistance. The two linezolid-resistant S. cohnii isolates were subjected to pulsed-field gel electrophoresis (PFGE) to investigate their genetic relatedness. Primer walking, S1 nuclease PFGE and Southern blot hybridisation were conducted to ascertain the location and environment of the cfr gene. All three isolates were positive for the cfr gene. Amino acid mutations S158F and S158Y in the ribosomal protein L3 were identified in S. cohnii 13B289 and 13L105, respectively, both of which also had an additional substitution (D159Y) in L3. PFGE indicated that the two S. cohnii isolates belonged to diverse clonal strains. S1 nuclease PFGE and Southern blotting experiments indicated that the cfr gene of the three isolates resided on plasmids of similar size (ca. 35.4kb). The cfr-harbouring segments of S. capitis 13G350 and S. cohnii 13L105 were identical to plasmid pSS-01 reported previously. The cfr-carrying fragment of S. cohnii 13B289 was indistinguishable from the formerly described plasmid pSS-02. In conclusion, the presence of the cfr gene located on a plasmid was the main mechanism contributing to resistance to linezolid in the three staphylococcal isolates. Hence, timely detection and judicious use of antibiotics are essential to prevent further transmission of this resistance mechanism. Copyright © 2016 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.

Genetic characterization of antimicrobial resistance in coagulase-negative staphylococci from bovine mastitis milk.

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Frey, Yvonne; Rodriguez, Joan Peña; Thomann, Andreas; Schwendener, Sybille; Perreten, Vincent

2013-04-01

Coagulase-negative staphylococci (CNS; n=417) were isolated from bovine milk and identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Nineteen different species were identified, and Staphylococcus xylosus, Staphylococcus chromogenes, Staphylococcus haemolyticus, and Staphylococcus sciuri were the most prevalent species. Resistance to oxacillin (47.0% of the isolates), fusidic acid (33.8%), tiamulin (31.9%), penicillin (23.3%), tetracycline (15.8%), streptomycin (9.6%), erythromycin (7.0%), sulfonamides (5%), trimethoprim (4.3%), clindamycin (3.4%), kanamycin (2.4%), and gentamicin (2.4%) was detected. Resistance to oxacillin was attributed to the mecA gene in 9.7% of the oxacillin-resistant isolates. The remaining oxacillin-resistant CNS did not contain the mecC gene or mecA1 promoter mutations. The mecA gene was detected in Staphylococcus fleurettii, Staphylococcus epidermidis, Staph. haemolyticus, and Staph. xylosus. Resistance to tetracycline was attributed to the presence of tet(K) and tet(L), penicillin resistance to blaZ, streptomycin resistance to str and ant(6)-Ia, and erythromycin resistance to erm(C), erm(B), and msr. Resistance to tiamulin and fusidic acid could not be attributed to an acquired resistance gene. In total, 15.1% of the CNS isolates were multidrug resistant (i.e., resistant to 2 or more antimicrobials). The remaining CNS isolates were susceptible to antimicrobials commonly used in mastitis treatment. Methicillin-resistant CNS isolates were diverse, as determined by mecA gene sequence analysis, staphylococcal cassette chromosome mec typing, and pulsed-field gel electrophoresis. Arginine catabolic mobile element types 1 and 3 were detected in both methicillin-resistant and methicillin-susceptible Staph. epidermidis and were associated with sequence types ST59 and ST111. Because this study revealed the presence of multidrug-resistant CNS in a heterogeneous CNS population, we recommend antibiogram analysis

Bacteriological Study of 100 Cases of Pyodermas with Special Reference to Staphylococci, Their Antibiotic Sensitivity and Phage Pattern

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T V Ramani

1980-01-01

Full Text Available One hundred new cases of pyodenna attending King George Hospital, Vishakhapatnam were investigated bacteriologically with antibiotic sensitivity of all the strains isolated and phage typing of coagulm positive staphylocci. Among these 50 had impetigo and 15 each ahd furunculosis and fouiculitis. The remaining included various other clinical entities. Children under 10 years were observed to have high incidence of pyoderma. A total of 88 strains of staphylococci (77 coagulase positive and 11 coagulase negative strains 25 strains of beta haemolytic streptococci and 3 strains of Klebsiella were isolated. Staphylococci were found to be the commonest aetiological agents either single or in association with other organisms. Of the 76 strains of coagulase positive staphylococci 32 strains were not phage typable and among the 44 typable strains 17 (38% belonged to group III and 15 (36.5% to mixed group. Coagulase positive staphylococci showed high sensitivity to garamycin, kanamycin and erythromycin and high resistance to penicillin and streptomycin. Multiple drug resistance was also high among these strains. Coagulase negative staphylococci were found to be more sensitive with less incidence of multiple drug resistance. Most of multiple drug resistant strains belonged to group III phage types. Beta haemolytic streptococci were found to be highly sensitive to all the antibiotics tested.

High-resolution melt analysis for species identification of coagulase-negative staphylococci derived from bovine milk.

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Ajitkumar, Praseeda; Barkema, Herman W; Zadoks, Ruth N; Morck, Douglas W; van der Meer, Frank J U M; De Buck, Jeroen

2013-03-01

Coagulase-negative staphylococci (CNS) are the most frequently isolated pathogens isolated from bovine milk. In this study, we report a rapid assay for species identification of CNS using high-resolution melt analysis (HRMA) of 16S rDNA sequences. Real-time polymerase chain reaction amplification of 16S rRNA gene fragment, spanning the variable region V1 and V2, was performed with a resulting amplicon of 215 bp. A library of distinct melt curves of reference strains of 13 common CNS species was created using HRMA. Sequencing of 16S rRNA and rpoB genes, and, when needed, tuf gene, of 100 CNS isolates obtained from Canadian Bovine Mastitis Research Network was done to determine their species identity, allowing for subsequent evaluation of the performance of HRMA for field isolates of bovine CNS. A combination of HRMA and sequencing revealed that Staphylococcus chromogenes, S. xylosus, S. simulans, and S. sciuri had multiple genotypes, complicating their resolution by HRMA. As the 3 genotypes of S. chromogenes had distinct melt curves, the 3 distinct genotypes were employed as reference strains in a blinded trial of 156 CNS isolates to identify S. chromogenes. HRMA correctly identified all S. chromogenes isolates which were later confirmed by sequencing. Staphylococcus chromogenes (68%) was most frequently found among the CNS isolates, followed by S. haemolyticus (10%) and S. xylosus (6%). The present study revealed that HRMA of 16S rRNA gene (V1-V2) could be used as a rapid, efficient, low-cost, and minimally cumbersome technique for S. chromogenes identification, the most common CNS derived from bovine milk. Copyright © 2013 Elsevier Inc. All rights reserved.

Antibiotic resistance of coagulase-negative staphylococci isolated from artisanal Naples-type salami.

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Mauriello, G; Moschetti, G; Villani, F; Blaiotta, G; Coppola, S

2000-01-01

In the present paper 42 isolates from Italian salami were specified as Staphylococcus xylosus (30), Staph. capitis (1), Staph. saprophyticus (1), Staph. hominis (1), Staph. simulans (1), Staph. cohnii (1) and as Staph. spp. (7). These strains were coagulase-negative and were examined for resistance/sensitivity against 25 antibiotics including beta-lactams (7), macrolides (3), amynoglicosides (5), glycopeptides, lincosamides (4) and novobiocin, fusidic acid, chloramphenicol, rifampicin, tetracycline, minocycline. More than 64% of the strains were resistant to lincomycin, penicillin G, amoxicillin, fusidic acid and novobiocin. All the strains were multiresistant and displayed at least three resistances. Over 75% had a multiple antibiotic resistance (MAR) index between 0.2 and 0.5.

The use of nucleosides and arginine as alternative energy sources by coagulase-negative staphylococci in view of meat fermentation.

Science.gov (United States)

Janssens, M; Van der Mijnsbrugge, A; Sánchez Mainar, M; Balzarini, T; De Vuyst, L; Leroy, F

2014-05-01

The ability of coagulase-negative staphylococci (CNS) to use alternative energy sources in meat may partially explain their occurrence in fermented meats. Of 61 CNS strains tested, all metabolized adenosine and inosine in a meat simulation medium (MSM). The ability to catabolize arginine via the arginine deiminase (ADI) pathway varied between strains. All tested strains of Staphylococcus carnosus and Staphylococcus epidermidis possessed an arcA gene and showed ADI activity, whereas other species, such as Staphylococcus equorum and Staphylococcus succinus, did not. Arginine catabolic mobile elements (ACME), as in the positive control S. epidermidis ATCC 12228, were uncommon and only found in Staphylococcus xylosus 3PA6 (sausage isolate) and Staphylococcus chromogenes G222 (teat apex isolate). Monoculture experiments were performed in MSM with S. carnosus 833 and SS3-4, S. xylosus G211, and S. epidermidis ATCC 12228 and 2S7-4. At all pH values tested (5.3, 5.8, and 6.5), the strains of S. carnosus catabolized arginine faster than the strains of S. xylosus and S. epidermidis. Only at pH 6.5 could a low ADI activity be found for S. xylosus G211. Increased ADI activity occurred in the case of the ACME-positive S. epidermidis ATCC 12228, when compared to the ACME-negative S. epidermidis 2S7-4. Copyright © 2013 Elsevier Ltd. All rights reserved.

Methicillin resistance of airborne coagulase-negative staphylococci in homes of persons having contact with a hospital environment.

Science.gov (United States)

Lis, Danuta O; Pacha, Jerzy Z; Idzik, Danuta

2009-04-01

The persons having contact with a hospital environment (hospital personnel workers and discharged patients) are highly exposed to colonization with multidrug-resistant bacteria. The aim of this study was to evaluate the airborne Staphylococcus genus features in homes in which inhabitants have had contact with the hospital environment. Airborne bacteria were collected using a 6-stage Anderson impactor. The Staphylococcus species composition and resistance to methicillin, and other antimicrobial agents among 3 coagulase-negative staphylococci (CNS) species (S cohnii spp cohnii, S epidermidis, S hominis), were determined. Antibiotic resistance of isolates was tested using the agar screen method with methicillin, the polymerase chain reaction technique to detect the mecA gene, and the disk diffusion method. A higher prevalence of methicillin-resistant (MR) strains among the species isolated (40% of S epidermidis, 40% of S hominis, and 60% of S cohnii spp cohnii) was found in homes of persons who had contact with a hospital environment compared with the reference homes (only 12% of S hominis). The mecA gene was revealed in all MR S epidermidis strains and in some MR S hominis (50%) and S cohnii spp cohnii (33%) strains. All isolated MR CNS strains were susceptible to vancomycin, rifampicin, and linezolid. High numbers of airborne multidrug-resistant MR CNS in the homes of persons having contact with a hospital environment indicates that such inhabitants pose a risk of intrafamilial spreading of MR strains via air.

Reliability of the MicroScan WalkAway PC21 panel in identifying and detecting oxacillin resistance in clinical coagulase-negative staphylococci strains.

Science.gov (United States)

Olendzki, A N; Barros, E M; Laport, M S; Dos Santos, K R N; Giambiagi-Demarval, M

2014-01-01

The purpose of this study was to determine the reliability of the MicroScan WalkAway PosCombo21 (PC21) system for the identification of coagulase-negative staphylococci (CNS) strains and the detection of oxacillin resistance. Using molecular and phenotypic methods, 196 clinical strains were evaluated. The automated system demonstrated 100 % reliability for the identification of the clinical strains Staphylococcus haemolyticus, Staphylococcus hominis and Staphylococcus cohnii; 98.03 % reliability for the identification of Staphylococcus epidermidis; 70 % reliability for the identification of Staphylococcus lugdunensis; 40 % reliability for the identification of Staphylococcus warneri; and 28.57 % reliability for the identification of Staphylococcus capitis, but no reliability for the identification of Staphylococcus auricularis, Staphylococcus simulans and Staphylococcus xylosus. We concluded that the automated system provides accurate results for the more common CNS species but often fails to accurately identify less prevalent species. For the detection of oxacillin resistance, the automated system showed 100 % specificity and 90.22 % sensitivity. Thus, the PC21 panel detects oxacillin-resistant strains, but is limited by the heteroresistance that is observed when using most phenotypic methods.

One-year mortality in coagulase-negative Staphylococcus and Staphylococcus aureus infective endocarditis

DEFF Research Database (Denmark)

Rasmussen, Rasmus V; Snygg-Martin, Ulrika; Olaison, Lars

2009-01-01

The aim of this study was to investigate in-hospital mortality and 12-month mortality in patients with coagulase-negative Staphylococcus (CoNS) compared to Staphylococcus aureus (S. aureus) infective endocarditis (IE). We used a prospective cohort study of 66 consecutive CoNS and 170 S. aureus IE...

Interaction between bovine-associated coagulase-negative staphylococci species and strains and bovine mammary epithelial cells reflects differences in ecology and epidemiological behavior.

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Souza, F N; Piepers, S; Della Libera, A M M P; Heinemann, M B; Cerqueira, M M O P; De Vliegher, S

2016-04-01

Bacteria adherence seems to be an essential first stage for the internalization of bacteria into the cytoplasm of the host cell, which is considered an important virulence strategy enabling bacteria to occupy a microenvironment separated from host defense mechanisms. Thus, this study aimed to explore the difference in the capacity of 4 bovine-associated staphylococci species or strains to adhere to and internalize into bovine mammary epithelial cells (MEC). Three different isolates of coagulase-negative staphylococci (CNS) were used: one strain of Staphylococcus fleurettii isolated from sawdust and considered an environmental opportunistic bacterium, and 2 dissimilar Staphylococcus chromogenes isolates, one cultured from a heifer's teat apex (Staph. chromogenes TA) and the other originating from a chronic intramammary infection (Staph. chromogenes IM). Also, one well-characterized strain of Staphylococcus aureus (Newbould 305) was used for comparison with a major mastitis pathogen. The CNS species and strains adhered to and internalized into MEC slower than did Staph. aureus. Still, we observed high variation in adhesion and internalization capacity among the different CNS, with Staph. chromogenes IM showing a greater ability to adhere to and internalize into MEC than the 2 CNS strains isolated from extramammary habitats. In conclusion, the 3 well-characterized bovine-associated CNS species and strains originating from distinct habitats showed clear differences in their capacity to adhere to and internalize into MEC. The observed differences might be related to their diversity in ecology and epidemiological behavior. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Isolation of coagulase-positive staphylococci from bitches' colostrum and milk and genetic typing of methicillin-resistant Staphylococcus pseudintermedius strains.

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Rota, Ada; Corrò, Michela; Drigo, Ilenia; Bortolami, Alessio; Börjesson, Stefan

2015-07-23

Among the coagulase-positive, potentially pathogenic staphylococci, Staphylococcus pseudintermedius has been frequently isolated from bitches' milk. This organism colonizes the mammary gland or causes infection, while S. aureus has been only occasionally reported. The objective of this study was to investigate the occurrence and persistence of coagulase-positive staphylococci in the colostrum and milk of postpartum bitches, either treated or untreated with antimicrobials, and to assess the incidence, antibiotic resistance profile and genetic type of the methicillin-resistant strains. On postpartum D1, D7 and D15, drops of secretion were collected from the mammary glands of 27 postpartum bitches, nine of which were treated with antimicrobials. Coagulase-positive staphylococci were identified, antimicrobial susceptibility and the presence of mecA were tested and the genetic profile of methicillin-resistant strains was assessed. Staphylococcus pseudintermedius was the only coagulase-positive staphylococcus isolated, and its presence was detected in 21 out of 27 bitches and in 66 out of 145 swabs. In a single bitch, it caused puerperal mastitis. In untreated bitches, the frequency of isolation was lower in colostrum than in milk. All of the isolates except one were resistant to at least three antimicrobial classes, while 14 out of 66 S. pseudintermedius strains were methicillin-resistant mecA positive (MRSP) and were isolated from eight bitches housed in the same breeding kennel. A significant association was found between antimicrobial treatment and the presence of MRSP. Six of the 12 typed isolates belonged to spa-type t02 carrying SCCmec II/III, and another six were non-typeable with spa carrying SCCmec IV. The t02-SCCmec II/III isolates were sequence type (ST) 71; four NT-SCCmec IV isolates were ST258 and two were ST369. PFGE showed that isolates from the same dog had identical band patterns, while isolates from different dogs had unique band patterns. MRSP strains

Tetracycline resistance phenotypes and genotypes of coagulase-negative staphylococcal isolates from bubaline mastitis in Egypt.

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El-Razik, K A Abd; Arafa, A A; Hedia, R H; Ibrahim, E S

2017-06-01

This study was devoted to elucidate the tetracycline resistance of coagulase-negative staphylococci (CNS) derived from normal and subclinical mastitic (SCM) buffaloes' milk in Egypt. A total of 81 milk samples from 46 normal buffalo milk samples and 35 SCM buffalo milk samples at private dairy farms of Egypt were used in this study. CNS were identified using phenotypic and molecular methods (polymerase chain reaction [PCR]). CNS isolates were tested for tetracycline resistance using routine methods and multiplex PCR targeting tetracycline ( tet ) resistance genes followed by sequencing of positive PCR products and phylogenetic analysis. Isolation and identification of 28 (34.5%) CNS from normal and SCM buffaloes' milk, namely, Staphylococcus intermedius (39.2%), Staphylococcus xylosus (25.0%), Staphylococcus epidermidis (10.7%), Staphylococcus hominis (10.7%), and 3.5% to each of Staphylococcus sciuri , Staphylococcus hyicus , Staphylococcus lugdunensis , and Staphylococcus simulans . Using nested PCR, all the 28 CNS isolates revealed positive for 16srRNA gene specific for genus staphylococci and negative for thermonuclease ( nuc ) gene specific for Staphylococcus aureus species. The presence of tetracycline resistance-encoding genes ( tet K, tet L, tet M, and tet O) was detected by multiplex PCR. All isolates were negative for tet L, M, and O genes while 14 (50%) CNS isolates were positive for tet K gene, namely, S. lugdunensis (100%), S. hominis (100%), S. epidermidis (66.6%), S. intermedius (45.4%), and S. xylosus (42.8%). Nucleotide sequencing of tet K gene followed by phylogenetic analysis showed the high homology between our CNS isolates genes of tetracycline resistance with S. aureus isolates including Egyptian ones. This proves the transfer of the tetracycline resistance encoding genes between coagulase-negative and coagulase positive Staphylococcus spp. CNS isolates have distinguishingly high resistance to tetracycline. Abundant tetracycline usage for

Tetracycline resistance phenotypes and genotypes of coagulase-negative staphylococcal isolates from bubaline mastitis in Egypt

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K. A. Abd El-Razik

2017-06-01

Full Text Available Aim: This study was devoted to elucidate the tetracycline resistance of coagulase-negative staphylococci (CNS derived from normal and subclinical mastitic (SCM buffaloes' milk in Egypt. Materials and Methods: A total of 81 milk samples from 46 normal buffalo milk samples and 35 SCM buffalo milk samples at private dairy farms of Egypt were used in this study. CNS were identified using phenotypic and molecular methods (polymerase chain reaction [PCR]. CNS isolates were tested for tetracycline resistance using routine methods and multiplex PCR targeting tetracycline (tet resistance genes followed by sequencing of positive PCR products and phylogenetic analysis. Results: Isolation and identification of 28 (34.5% CNS from normal and SCM buffaloes' milk, namely, Staphylococcus intermedius (39.2%, Staphylococcus xylosus (25.0%, Staphylococcus epidermidis (10.7%, Staphylococcus hominis (10.7%, and 3.5% to each of Staphylococcus sciuri, Staphylococcus hyicus, Staphylococcus lugdunensis, and Staphylococcus simulans. Using nested PCR, all the 28 CNS isolates revealed positive for 16srRNA gene specific for genus staphylococci and negative for thermonuclease (nuc gene specific for Staphylococcus aureus species. The presence of tetracycline resistance-encoding genes (tetK, tetL, tetM, and tetO was detected by multiplex PCR. All isolates were negative for tetL, M, and O genes while 14 (50% CNS isolates were positive for tetK gene, namely, S. lugdunensis (100%, S. hominis (100%, S. epidermidis (66.6%, S. intermedius (45.4%, and S. xylosus (42.8%. Nucleotide sequencing of tetK gene followed by phylogenetic analysis showed the high homology between our CNS isolates genes of tetracycline resistance with S. aureus isolates including Egyptian ones. This proves the transfer of the tetracycline resistance encoding genes between coagulase-negative and coagulase-positive Staphylococcus spp. Conclusion: CNS isolates have distinguishingly high resistance to tetracycline

Gevoeligheid voor diverse antibiotica van coagulase negatieve staphylococcen, geisoleerd uit melkmonsters van Nederlands rundvee

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Sampimon, O.C.; Vernooij, J.C.A.; Mevius, D.J.; Sol, J.

2007-01-01

During recent years the prevalence of coagulase-negative staphylococci in milk samples from Dutch dairy cows has increased. In 1999 16.2% of the bacteria isolated from milk collected from cows with subclinical mastitis were coagulasenegative staphylococci. In 2004 this proportion was 42.2%. The

Coagulase-negative staphylococci from non-mastitic bovine mammary gland: characterization of Staphylococcus chromogenes and Staphylococcus haemolyticus by antibiotic susceptibility testing and pulsed-field gel electrophoresis.

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Pate, Mateja; Zdovc, Irena; Avberšek, Jana; Ocepek, Matjaž; Pengov, Andrej; Podpečan, Ožbalt

2012-05-01

During routine microbiological examination of milk samples from dairy cows without clinical signs of mastitis, quarter milk samples of 231 dairy cows from 12 herds were investigated for the presence of coagulase-negative staphylococci (CNS). The isolates were identified on the basis of colony morphology, Gram staining, catalase and coagulase test and the commercial kit, API Staph. CNS was detected in 29% (67/231) of the cows. A total of seven CNS species were identified with the most prevalent being Staphylococcus (Staph.) chromogenes (30%) and Staph. haemolyticus (28·8%), followed by Staph. simulans (11·2%), Staph. xylosus (11·2%), Staph. epidermidis (7·5%), Staph. hyicus (6·3%) and Staph. sciuri (5%). The predominant species, Staph. chromogenes and Staph. haemolyticus, were further characterized by antibiotic susceptibility testing using the agar disc diffusion method (Kirby-Bauer) and by pulsed-field gel electrophoresis (PFGE). Considerable resistance to ampicillin and penicillin was observed in both species. Isolates with identical or highly similar PFGE profiles were detected at the herd level despite a marked heterogeneity seen for both species. On the basis of somatic cell count, absence of clinical signs of inflammation and heterogeneity of genotypes, we assume that CNS isolated in this study could not be considered as important causative agents of the bovine mammary gland inflammation.

Investigation into the prevalence, persistence and antibiotic resistance profiles of staphylococci isolated from euro currency.

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Gabriel, E M; Coffey, A; O'Mahony, J M

2013-08-01

The study set out to sample € 10 banknotes for the presence of coagulase-positive staphylococci (CPS) such as Staphylococcus aureus (S. aureus) and coagulase-negative staphylococci (CoNS) in Southern Ireland, to assess the levels of antibiotic resistance among those isolated, and determine the persistence of S. aureus on € 10 banknotes and € 2 coins. We report that 97% of € 10 banknotes screened (n = 155) harboured multiple species of staphylococci. From the generated bank of strains, a total of 150 representative staphylococci isolates were used for further study, 71 were CPS and 79 were CoNS. Of these, we found that 62% of the staphylococci demonstrated resistance to at least one of the first-line antibiotics (52.11% of CPS isolates and 76.71% of the CoNS isolates). Resistance to multiple antibiotics was seen in 31.18% of the resistant isolates. In relation to persistence studies, S. aureus was shown to remain viable on euro banknotes and coins for significant periods (on average, 19.33 days on € 10 banknotes and 16.67 days on € 2 coins) as determined using bioluminescence. We advocate the expansion of antibiotic surveillance programs, with a view to tracking/monitoring antibiotic resistance dissemination among environmental contaminants. Additionally, we propose that 'cashless transactions' should be encouraged in high-risk environments such as hospitals and healthcare settings, as well as stricter infection controls. Although it is accepted that circulating currency has the potential to harbour disease-causing pathogens, studies investigating prevalence and persistence of such pathogens on euro currency are virtually nonexistent. In an attempt to rectify this, we examined the prevalence of staphylococci on € 10 banknotes in Ireland and reported relatively high levels of antibiotic resistance among the isolates. Furthermore, we have established the persistence of S. aureus on euro currency for the first time. © 2013 The Society for Applied

Enterotoxin Producing Ability And Antimicrobial Susceptibility Of Coagulase-Negative Staphylococci Isolated From Goat Milk Cheese And Salted Yoghurt In Turkey

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S. Pehlivanlar Onen

2017-10-01

Full Text Available The aim of this study was to determine enterotoxin producing ability and antimicrobial susceptibility of coagulase negative staphylococci CNS in goats bulk milk cheese and salted yoghurt. CNS strains were identified by using GP card in VITEK 2 system. The presence of enterotoxins was determined by enzyme immunoassay test by using RIDASCREEN test kit. Antibiotic susceptibility in CNS strains was detected by using AST-P640 card in VITEK 2 system. A total of 100 CNS strains were isolated in 22 55 bulk milk samples and in 23 57.5 cheese samples. Staphylococcus spp. could not be isolated from salted yoghurt samples. The most encountered species were S. caprae 51.9 S. chromogenes 11.5 and S. xylosus 9.6 from milk samples and S. saprophyticus 60.4 S. xylosus 12.5 and S. haemolyticus 8.3 from cheese samples. Four CNS strains 4 isolated from samples were capable of producing enterotoxin. While all isolates were resistant to at least one antibiotic 74 of CNS strains showed resistance to two or more antibiotics. Enterotoxin production ability and high antibiotic resistance of the CNS strains isolated from goat bulk milk and cheese can lead to a risk for public health.

Unraveling the microbiota of teat apices of clinically healthy lactating dairy cows, with special emphasis on coagulase-negative staphylococci.

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Braem, G; De Vliegher, S; Verbist, B; Piessens, V; Van Coillie, E; De Vuyst, L; Leroy, F

2013-03-01

Swab samples (n=72) obtained from the teat apex of lactating dairy cows without visual signs of inflammation (n=18) were gathered on 2 well-managed Flemish dairy herds (herds 1 and 2) during the same month to assess the bacterial diversity of teat apices before milking. A combination of both culture-dependent [plating and (GTG)(5)-PCR fingerprinting of the colonies] and culture-independent [denaturing gradient gel electrophoresis (PCR-DGGE)] techniques indicated that the teat apices contain a wide diversity of bacterial genera. Despite a low bacterial load, 20 bacterial genera of 3 phyla (Actinobacteria, Firmicutes, and Proteobacteria) were present. The most prevalent bacteria were the coagulase-negative staphylococci (CNS), encompassing a total of 15 species, which were identified to the species level using a combination of (GTG)(5)-PCR fingerprinting, gene sequencing (16S ribosomal RNA and rpoB genes), and a novel PCR-DGGE technique based on the tuf-PCR amplicon. Overall bacterial diversity did not differ significantly between the herds or between noninfected and subclinically infected quarters in herd 1. In herd 1, borderline significant lower CNS species diversity was found on teat apices of noninfected quarters compared with subclinically infected quarters. The most prevalent CNS species were Staphylococcus haemolyticus and Staphylococcus equorum in both herds and Staphylococcus carnosus in herd 2. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Prevalence and characteristics of methicillin-resistant coagulase-negative staphylococci from livestock, chicken carcasses, bulk tank milk, minced meat, and contact persons

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Zweifel Claudio

2011-01-01

Full Text Available Abstract Background Methicillin-resistant coagulase-negative staphylococci (MR-CNS are of increasing importance to animal and public health. In veterinary medicine and along the meat and milk production line, only limited data were so far available on MR-CNS characteristics. The aim of the present study was to evaluate the prevalence of MR-CNS, to identify the detected staphylococci to species level, and to assess the antibiotic resistance profiles of isolated MR-CNS strains. Results After two-step enrichment and growth on chromogenic agar, MR-CNS were detected in 48.2% of samples from livestock and chicken carcasses, 46.4% of samples from bulk tank milk and minced meat, and 49.3% of human samples. Using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS, 414 selected MR-CNS strains belonged to seven different species (S. sciuri, 32.6%; S. fleurettii, 25.1%; S. haemolyticus, 17.4%; S. epidermidis, 14.5%, S. lentus, 9.2%; S. warneri, 0.7%; S. cohnii, 0.5%. S. sciuri and S. fleurettii thereby predominated in livestock, BTM and minced meat samples, whereas S. epidermidis and S. haemolyticus predominated in human samples. In addition to beta-lactam resistance, 33-49% of all 414 strains were resistant to certain non-beta-lactam antibiotics (ciproflaxacin, clindamycin, erythromycin, tetracycline. Conclusions A high prevalence of MR-CNS was found in livestock production. This is of concern in view of potential spread of mecA to S. aureus (MRSA. Multiresistant CNS strains might become an emerging problem for veterinary medicine. For species identification of MR-CNS isolated from different origins, MALDI-TOF MS proved to be a fast and reliable tool and is suitable for screening of large sample amounts.

Diversity of staphylococcal cassette chromosome mec structures in coagulase-negative staphylococci and relationship to drug resistance.

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Garza-González, Elvira; López, Daniel; Pezina, Cesar; Muruet, Walter; Bocanegra-García, Virgilio; Muñoz, Ivan; Ramírez, Camilo; Llaca-Díaz, Jorge M

2010-03-01

The objective of this study was to determine the distribution of staphylococcal cassette chromosome mec (SCCmec) elements in meticillin-resistant coagulase-negative staphylococci (MR-CoNS) isolated from a tertiary-care hospital in Mexico and to examine the relationship to drug resistance. Fifty selected MR-CoNS isolates collected from catheters (n=15), blood (n=15), bone (n=9), bronchial lavage (n=2) and urine (n=2) and one isolate each from an abscess, cerebrospinal fluid, eye, pleural effusion, synovial fluid, tracheal aspirate and wound secretion were examined. Susceptibility testing was performed by the broth microdilution method. SCCmec types were determined by multiplex PCR and PFGE was carried out as described previously for Staphylococcus aureus. Among the MR-CoNS strains studied, the most frequently isolated species were Staphylococcus epidermidis (n=26) and Staphylococcus haemolyticus (n=13). Staphylococcus cohnii (n=5), Staphylococcus hominis (n=3), Staphylococcus sciuri (n=1), Staphylococcus pasteuri (n=1) and the recently described species Staphylococcus pettenkoferi (n=1) were also identified. The most frequent MR-CoNS genotype identified was SCCmec type IVa in S. epidermidis isolates, which also showed a high diversity in their PFGE patterns. A clone was found that amplified both SCCmec III and V elements in five isolates examined. The single MR S. pettenkoferi isolate harboured SCCmec type IVd and the single MR S. pasteuri isolate harboured SCCmec type I. The carriage of SCCmec type III was associated with resistance or intermediate resistance to meropenem (P <0.05). These results confirm the high prevalence of S. epidermidis SCCmec IVa and the high genetic diversity among MR-CoNS strains. As far as is known, this is the first report describing the newly identified S. pettenkoferi possessing SCCmec IVd and S. pasteuri harbouring SCCmec type I. MR-CoNS harbouring SCCmec type III were found to be more resistant to meropenem.

AzaSite® inhibits Staphylococcus aureus and coagulase-negative Staphylococcus biofilm formation in vitro.

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Wu, Eric C; Kowalski, Regis P; Romanowski, Eric G; Mah, Francis S; Gordon, Y Jerold; Shanks, Robert M Q

2010-12-01

The aim of this study was to analyze the effect of azithromycin (AZM) 1% ophthalmic solution in DuraSite® (AzaSite®) on biofilm formation by Staphylococcus aureus and coagulase-negative staphylococci in vitro. Susceptible and resistant clinical strains (n = 8) of S. aureus and coagulase-negative staphylococci were challenged with serial dilutions of AzaSite® and its components: AZM, benzalkonium chloride (BAK), and the DuraSite drug delivery vehicle. After 20 h of incubation, bacterial growth was quantified using a spectrophotometer (A = 600 nm). Plates were stained with crystal violet and biofilm formation was quantified spectrophotometrically at A = 590 nm. AzaSite® and AZM inhibited bacterial growth (P reduction in biofilm formation (P reduction in biofilm formation at concentrations from 1.25 to 10 mg/mL in most strains. DuraSite® inhibited biofilm formation at concentrations between 10% and 2.5% in all studied strains (P < 0.05), without affecting bacterial growth. BAK inhibited bacterial growth and biofilm formation in all strains between concentrations of 0.042 and 0.375 mg/mL (P < 0.05). AzaSite®, AZM, or BAK prevented biofilm formation by inhibiting growth of AZM-susceptible strains. AzaSite®, AZM, and DuraSite® also reduced biofilm formation at subinhibitory concentrations for growth. Our data indicate that AZM has a moderate inhibitory effect on biofilm formation, whereas DuraSite® appears to play a greater role in the inhibition of staphylococcal biofilm formation by AzaSite®.

[A case of subarachnoid hemorrhage due to infective endocarditis by methicillin-resistant coagulase-negative staphylococcus].

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Kajikawa, Shunsuke; Oeda, Tomoko; Park, Kwiyoung; Yamamoto, Kenji; Sugiyama, Hiroshi; Sawada, Hideyuki

2017-12-27

A 77-year-old man visited our hospital with unstable gait following 2 months of anorexia. Brain MRI showed multiple infarcts; cardiac echocardiography revealed mitral-valve vegetation; and blood culture revealed methicillin-resistant coagulase-negative staphylococci. The patient was diagnosed with infective endocarditis (IE). Subarachnoid hemorrhage (SAH) developed ten days after antibiotic treatment. Intracranial aneurysm was not found. We speculated that chronic inflammation of the cerebral arterial walls by bacteria of low virulence was associated with SAH complication. The vegetation disappeared following additional gentamicin administration and the patient recovered to walk.

Genotypic and phenotypic β-lactam resistance and presence of PVL gene in Staphylococci from dry bovine udder.

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Vinodkumar Kulangara

Full Text Available Dairy cows affected with subclinical mastitis can be sources of virulent, antimicrobial-resistant Staphylococci to humans because of the excretion of the bacteria through their milk. This study focussed on the phenotypic and genotypic antibiotic resistance patterns of Staphylococci isolated from dairy cows in early dry period. Among 96 isolates of Gram positive cocci from 157 cows, 76 were identified as Coagulase Negative Staphylococci and the remaining 20 were Staphylococcus aureus. Typical amplicons of coagulase gene were obtained for all 20 samples of S. aureus with three major coagulase types being identified as giving 627 bp (40%, 910 bp (35% and 710 bp (25% long PCR products. The groEL gene was amplified in PCR of all 76 isolates of Coagulase Negative Staphylococci, and incubation of PCR products with restriction enzyme PvuII yielded three distinct PCR-RFLP fragment patterns bearing resemblance to S. chromogenes and S. hyicus. Highest sensitivity of Coagulase Negative Staphylococci was noted for Azithromycin (92.5% and the least to Tetracyclines (76.3%, whereas for S. aureus, it was Cefoperazone (95% and Azithromycin (72.2% respectively. Phenotypic resistance to Oxacillin (25 isolates, and Cefoxitin (11 isolates was detected by dilution method with a commercial strip (Ezy MICTM. Genotypic resistance to β-Lactam antibiotics was found in 65 (34 with mecA gene and 31 with blaZ gene isolates. Eighteen isolates possessed both the genes, with the PVL gene for virulence being detected in five of them. Nine isolates which had mecA gene were phenotypically susceptible to oxacillin while phenotypic resistance to oxacillin was observed in seven isolates that did not have either mecA or blaZ gene. This is the first report of persistent Staphylococcal infections possessing PVL gene and high level of genotypic resistance to β-Lactam antibiotics in small- holder dairy cattle from India.

Genotypic and phenotypic β-lactam resistance and presence of PVL gene in Staphylococci from dry bovine udder

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Sivasailam, Asok; Sasidharan, Suchithra; Kollannur, Justin Davis; Syam, Radhika

2017-01-01

Dairy cows affected with subclinical mastitis can be sources of virulent, antimicrobial-resistant Staphylococci to humans because of the excretion of the bacteria through their milk. This study focussed on the phenotypic and genotypic antibiotic resistance patterns of Staphylococci isolated from dairy cows in early dry period. Among 96 isolates of Gram positive cocci from 157 cows, 76 were identified as Coagulase Negative Staphylococci and the remaining 20 were Staphylococcus aureus. Typical amplicons of coagulase gene were obtained for all 20 samples of S. aureus with three major coagulase types being identified as giving 627 bp (40%), 910 bp (35%) and 710 bp (25%) long PCR products. The groEL gene was amplified in PCR of all 76 isolates of Coagulase Negative Staphylococci, and incubation of PCR products with restriction enzyme PvuII yielded three distinct PCR-RFLP fragment patterns bearing resemblance to S. chromogenes and S. hyicus. Highest sensitivity of Coagulase Negative Staphylococci was noted for Azithromycin (92.5%) and the least to Tetracyclines (76.3%), whereas for S. aureus, it was Cefoperazone (95%) and Azithromycin (72.2%) respectively. Phenotypic resistance to Oxacillin (25 isolates), and Cefoxitin (11 isolates) was detected by dilution method with a commercial strip (Ezy MICTM). Genotypic resistance to β-Lactam antibiotics was found in 65 (34 with mecA gene and 31 with blaZ gene) isolates. Eighteen isolates possessed both the genes, with the PVL gene for virulence being detected in five of them. Nine isolates which had mecA gene were phenotypically susceptible to oxacillin while phenotypic resistance to oxacillin was observed in seven isolates that did not have either mecA or blaZ gene. This is the first report of persistent Staphylococcal infections possessing PVL gene and high level of genotypic resistance to β-Lactam antibiotics in small- holder dairy cattle from India. PMID:29091956

Poststaphylococcal coagulase negative reactive arthritis: a case report.

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Krasniqi, Xhevdet; Rexhepi, Sylejman; Gashi, Masar; Berisha, Blerim; Abazi, Flora; Koçinaj, Dardan

2009-12-18

We report a case of a 49-year-old patient who developed poststaphylococcal coagulase negative reactive arthritis. The woman presented with constitutional symptoms, arthritis, urinary infection and conjunctivitis. The blood culture was positive for the staphylococcal coagulase negative infection. Erythrocyte sedimentation rate and C-reactive protein were elevated, whereas the rheumatoid factor was negative. Radiographic findings confirmed diagnosis of pleuropneumonia, and one year later of chronic asymmetric sacroileitis. Physicians should be aware of possible reactive arthritis after staphylococcal coagulase negative bacteremia.

Antibiotic resistance profile of staphylococci from clinical sources ...

African Journals Online (AJOL)

Infants, children and the aged are among the groups most vulnerable to microbial infections more so when these microbial agents become resistant to antimicrobials. The antibiotic resistant profile of Staphylococcus aureus and selected coagulase negative staphylococci were determined by standard methods. Of the 178 ...

Intramammary infection with coagulase-negative staphylococci at parturition: Species-specific prevalence, risk factors, and effect on udder health.

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De Visscher, A; Piepers, S; Haesebrouck, F; De Vliegher, S

2016-08-01

Coagulase-negative staphylococci (CNS) are the main cause of bovine intramammary infections (IMI) in many countries. Despite a high prevalence of CNS IMI at parturition, species-specific risk factor studies, relying on accurate identification methods, are lacking. Therefore, this observational study aimed at determining the prevalence and distribution of different CNS species causing IMI in fresh heifers and dairy cows in Flemish dairy herds and identifying associated species- and subgroup-specific risk factors at the herd, cow, and quarter level. The effect on udder health was investigated as well. Staphylococcus chromogenes, S. sciuri, and S. cohnii were the most frequently isolated species. The only CNS species causing IMI in fresh heifers and dairy cows in all herds was Staphylococcus chromogenes, whereas large between-herd differences in distribution were observed for the other species. Quarters from heifers and quarters with an inverted teat end had higher odds of being infected with S. chromogenes, S. simulans, or S. xylosus as well as with S. chromogenes solely. Prepartum teat apex colonization with S. chromogenes increased the likelihood of S. chromogenes IMI in the corresponding quarters at parturition. Quarters with dirty teat apices before calving were more likely to be infected with S. cohnii, S. equorum, S. saprophyticus, or S. sciuri, supporting the environmental nature of these CNS species. Three species (S. chromogenes, S. simulans, and S. xylosus) were associated with a higher quarter somatic cell count at parturition as compared with uninfected quarters. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Further evidence for the existence of environmental and host-associated species of coagulase-negative staphylococci in dairy cattle.

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De Visscher, Anneleen; Supré, Karlien; Haesebrouck, Freddy; Zadoks, Ruth N; Piessens, Veerle; Van Coillie, Els; Piepers, Sofie; De Vliegher, Sarne

2014-08-27

Coagulase-negative staphylococci (CNS) are abundantly present in the dairy farm environment and on bovine skin and mucosae. They are also the most prevalent bacteria causing bovine intramammary infections (IMI). Reservoirs and transmission routes of CNS are not yet fully unraveled. The objectives of this study were to explore the distribution of CNS in parlor-related extramammary niches and to compare it to the distributions of CNS causing IMI in those herds. Niches that were targeted in this study were cows' teat apices, milking machine unit liners, and milker's skin or gloves. Each of the three herds had its own CNS microbiota in those niches. The most prevalent species in the parlor-related extramammary niches were Staphylococcus cohnii, S. fleurettii, and S. equorum in the first, second, and third herd, respectively, whereas S. haemolyticus and S. sciuri were found in all herds. S. cohnii and S. fleurettii, as well as S. haemolyticus, which was present in each herd, were also frequently found in milk samples. By contrast, S. chromogenes, S. simulans, and S. xylosus favored the mammary gland, whereas S. equorum was more common in the parlor-associated niches. Within each herd, species distribution was similar between teat apices and milking machine unit liners. In conclusion, some of the extramammary niches related to the milking process might act as infection sources for IMI-causing CNS. This study provides further evidence that the group of CNS species is comprised of environmental, opportunistic and host-adapted species which differ in ecology. Copyright © 2014 Elsevier B.V. All rights reserved.

Coagulase-negative staphylococcal bacteraemia in cancer patients. Time to positive culture can distinguish bacteraemia from contamination.

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Morioka, Shinichiro; Ichikawa, Mika; Mori, Keita; Kurai, Hanako

2018-03-16

Coagulase-negative staphylococci (CoNS) are the most common contaminants of blood cultures, however, we sometimes have difficulties in determining their clinical significance. It is still controversial that there is a significant difference between the contamination group and the true bacteraemia group in the time to positivity (TTP) of blood cultures. We validated the relationship between a TTP and the presence of CoNS bacteraemia in cancer patients by using an objective, non-judgmental definition for CoNS contamination. We retrospectively reviewed 175 sets of blood cultures drawn from 95 patients that yielded CoNS from October 2011 to March 2013. We considered as contamination if an isolate of CoNS was identified in one out of multiple sets of blood cultures. We investigated the TTP, the threshold values and corresponding likelihood ratios to distinguish CoNS bacteraemia from contamination. The median TTP in CoNS bacteraemia group was significantly shorter than that in contamination group (14 h 45 min and 20 h 31 min, respectively, p = .0157). A TTP of ≤16 h had a specificity of 83% for predicting CoNS bacteraemia, and that of >20 h had a sensitivity of 86% for predicting CoNS contamination. We validated that the median TTP in CoNS bacteraemia group was significantly shorter than that in their contamination group, and that a TTP of ≤16 h was associated with CoNS bacteraemia, while that of >20 h was associated with CoNS contamination, if evaluated with an objective, non-judgmental definition for CoNS contamination.

Understanding the physiology and adaptation of staphylococci: a post-genomic approach.

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Becker, Karsten; Bierbaum, Gabriele; von Eiff, Christof; Engelmann, Susanne; Götz, Friedrich; Hacker, Jörg; Hecker, Michael; Peters, Georg; Rosenstein, Ralf; Ziebuhr, Wilma

2007-11-01

Staphylococcus aureus as well as coagulase-negative staphylococci are medically highly important pathogens characterized by an increasing resistance rate toward many antibiotics. Although normally being skin and mucosa commensals, some staphylococcal species and strains have the capacity to cause a wide range of infectious diseases. Many of these infections affect immunocompromised patients in hospitals. However, community-acquired staphylococcal infections due to resistant strains are also currently on the rise. In the light of this development, there is an urgent need for novel anti-staphylococcal therapeutic and prevention strategies for which a better understanding of the physiology of these bacteria is an essential prerequisite. Within the past years, staphylococci have been in the focus of genomic research, resulting in the determination and publication of a range of full-genome sequences of different staphylococcal species and strains which provided the basis for the design and application of DNA microarrays and other genomic tools. Here we summarize the results of the project group 'Staphylococci' within the research network 'Pathogenomics' giving new insights into the genome structure, molecular epidemiology, physiology, and genetic adaptation of both S. aureus and coagulase-negative staphylococci.

Epidemiology of drug resistance: The case of Staphylococcus aureus and coagulase-negative staphylococci infections Epidemiología de la resistencia bacteriana: el caso de Staphylococcus aureus y las infecciones Staphylococcus coagulasa negativas

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Ernesto Calderón-Jaimes

2002-04-01

Full Text Available Objective. To study the activity of several antibiotics against Staphylococcus spp. Material and Methods. The study included 1209 strains of Staphylococcus spp. from two institutions; Instituto Nacional de Pediatría (National Institute of Pediatrics and Hospital Infantil de México Federico Gómez (Mexico City Children's Hospital. Minimum Inhibitory Concentrations of all antibiotics were determined by the agar macrodilution technique and standard methods from the National Committee for Clinical Laboratory Standards. Results. Resistance of S. aureus was 14.2% and that of coagulase-negative staphylococci was 53.4%. The activity of different antibiotics is presented in detail. Conclusions. Surveillance of strains resistant to methicillin is necessary.Objetivo. Determinar la frecuencia de la resistencia a la meticilina y la actividad de varios antibióticos. Material y métodos. Se incluyeron 1 209 cepas de Staphylococcus spp. procedentes de pacientes del Instituto Nacional de Pediatría y del Hospital Infantil de México Federico Gómez. Se utilizó la técnica de dilución en placas con agar. El procedimiento e interpretación fueron acordes con lo establecido por el National Committee for Clinical Laboratory Standards. Resultados. La frecuencia de la resistencia de S. aureus fue de 14.2% y de 53.4% en los Staphylococcus coagulasa negativa. La actividad de otros antimicrobianos se presenta en el texto. Conclusiones. Es necesario vigilar continuamente la progresión de la resistencia de Staphylococcus spp. a la meticilina.

Emergence of methicillin-resistant coagulase-negative staphylococci resistant to linezolid with rRNA gene C2190T and G2603T mutations.

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Cidral, Thiago André; Carvalho, Maria Cícera; Figueiredo, Agnes Marie Sá; de Melo, Maria Celeste Nunes

2015-10-01

The aim of this article were to determinate the mechanism of linezolid resistance in coagulase-negative methicillin-resistant staphylococci from hospitals in the northeast of Brazil. We identified the isolates using VITEK(®) 2 and MALDI-TOF. Susceptibility to antibiotics was measured by the disk-diffusion method and by Etest(®) . Extraction of the whole genome DNA was performed, followed by screening of all the strains for the presence of mecA and cfr genes. The domain V region of 23S rRNA gene was sequenced and then aligned with a linezolid-susceptible reference strain. Pulsed-field gel electrophoresis (PFGE) macro-restriction analysis was performed. Three linezolid-resistant Staphylococcus hominis and two linezolid-resistant Staphylococcus epidermidis strains were analyzed. The isolates showed two point mutations in the V region of the 23S rRNA gene (C2190T and G2603T). We did not detect the cfr gene in any isolate by PCR. The S. hominis showed the same pulsotype, while the S. epidermidis did not present any genetic relation to each other. In conclusion, this study revealed three S. hominis and two S. epidermidis strains with resistance to linezolid due to a double mutation (C2190T and G2603T) in the domain V of the 23S rRNA gene. For the first time, the mutation of C2190T in S. epidermidis is described. This study also revealed the clonal spread of a S. hominis pulsotype between three public hospitals in the city of Natal, Brazil. These findings highlight the importance of continued vigilance of linezolid resistance in staphylococci. © 2015 APMIS. Published by John Wiley & Sons Ltd.

Antibiotic resistance patterns of coagulase-negative staphylococcus strains isolated from blood cultures of septicemic patients in Turkey.

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Koksal, F; Yasar, H; Samasti, M

2009-01-01

The aim of this study is to determine antibiotic resistance patterns and slime production characteristics of coagulase-negative Staphylococci (CoNS) caused nosocomial bacteremia. A total of 200 CoNS strains were isolated from blood samples of patients with true bacteremia who were hospitalized in intensive care units and in other departments of Istanbul University Cerrahpasa Medical Hospital between 1999 and 2006. Among 200 CoNS isolates, Staphylococcus epidermidis was the most prevalent species (87) followed by Staphylococcus haemolyticus (23), Staphylococcus hominis (19), Staphylococcus lugdunensis (18), Staphylococcus capitis (15), Staphylococcus xylosus (10), Staphylococcus warneri (8), Staphylococcus saprophyticus (5), Staphylococcus lentus (5), Staphylococcus simulans (4), Staphylococcus chromogenes (3), Staphylococcus cohnii (1), Staphylococcus schleiferi (1), and Staphylococcus auricularis (1). Resistance to methicillin was detected in 67.5% of CoNS isolates. Methicillin-resistant CoNS strains were determined to be more resistant to antibiotics than methicillin-susceptible CoNS strains. Resistance rates of methicillin-resistant and methicillin-susceptible CoNS strains to the antibacterial agents, respectively, were as follows: gentamicin 90% and 17%, erythromycin 80% and 37%, clindamycin 72% and 18%, trimethoprim-sulfamethoxazole 68% and 38%, ciprofloxacin 67% and 23%, tetracycline 60% and 45%, chloramphenicol 56% and 13% and fusidic acid 25% and 15%. None of the strains were resistant to vancomycin and teicoplanin. Slime production was detected in 86 of 200 CoNS strains. Resistance to methicillin was found in 81% of slime-positive and in 57% of slime-negative strains. Our results indicated that there is a high level of resistance to widely used agents in causative methicillin-resistant CoNS strains. However fusidic acid has the smallest resistance ratio, with the exception of glycopeptides. Additionally, most S. epidermidis strains were slime

Short communication: Prevalence of methicillin resistance in coagulase-negative staphylococci and Staphylococcus aureus isolated from bulk milk on organic and conventional dairy farms in the United States.

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Cicconi-Hogan, K M; Belomestnykh, N; Gamroth, M; Ruegg, P L; Tikofsky, L; Schukken, Y H

2014-05-01

The objective of this study was to evaluate the presence of methicillin-resistant Staphylococcus aureus and coagulase-negative Staphylococcus spp. in bulk tank milk samples from 288 organic and conventional dairy farms located in New York, Wisconsin, and Oregon from March 2009 to May 2011. Due to recent publications reporting the presence mecC (a mecA homolog not detected by traditional mecA-based PCR methods), a combination of genotypic and phenotypic approaches was used to enhance the recovery of methicillin-resistant organisms from bulk tank milk. In total, 13 isolates were identified as methicillin resistant: Staph. aureus (n=1), Staphylococcus sciuri (n=5), Staphylococcus chromogenes (n=2), Staphylococcus saprophyticus (n=3), Staphylococcus agnetis (n=1), and Macrococcus caseolyticus (n=1). The single methicillin-resistant Staph. aureus isolate was identified from an organic farm in New York, for an observed 0.3% prevalence at the farm level. The methicillin-resistant coagulase-negative staphylococci prevalence was 2% in the organic population and 5% in the conventional population. We did not identify mecC in any of the isolates from our population. Of interest was the relatively high number of methicillin-resistant Staph. sciuri recovered, as the number of isolates from our study was considerably higher than those recovered from other recent studies that also assessed milk samples. Our research suggests that the presence of a potential methicillin-resistant Staphylococcus reservoir in milk, and likely the dairy farm population in the United States, is independent of the organic or conventional production system. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Further studies on staphylococci in meats. III. Occurrence and characteristics of coagulase-positive strains from a variety of nonfrozen market cuts.

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JAY, J M

1962-05-01

From 34 retail grocery stores and meat markets, 209 samples of nonfrozen meats were obtained and analyzed for coagulase-positive Staphylococcus aureus, employing six selective media. Sixty-seven (38.7%) of 173 samples obtained from 27 stores yielded S. aureus. No coagulase-positive S. aureus was isolated from 36 samples obtained from 7 of the stores. The 67 meats yielded 272 isolates from 10 different kinds of meats. There were 162 physiological strains represented when classified by store and 36 strains classified without regard to store of origin. The larger stores yielded fewer meats with staphylococci than the smaller stores. The meats from which S. aureus was recovered in the order of frequency of percentage recovery are as follows: chicken, pork liver, fish, spiced ham, round beef steak, hamburger, beef liver, pork chops, veal steak, and lamb chops. The following seven meats did not yield staphylococci: bologna, shucked oysters, olive and pickle loaf, salami, wieners, and chopped ham. Eighty-eight per cent of the isolates produced pigment, 85% were gelatinase positive, only 1 strain failed to form a precipitate on egg yolk agar, 92% formed deoxyribonuclease, 87% produced bound coagulase, 91% produced the alpha-hemolysin, 70% the delta-, 22% the beta-, and 6% were nil in this regard. The isolates are compared with hospital and other food strains, and their possible source in the meats is discussed.

Short communication: Evaluation of MALDI-TOF mass spectrometry and a custom reference spectra expanded database for the identification of bovine-associated coagulase-negative staphylococci.

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Cameron, M; Perry, J; Middleton, J R; Chaffer, M; Lewis, J; Keefe, G P

2018-01-01

This study evaluated MALDI-TOF mass spectrometry and a custom reference spectra expanded database for the identification of bovine-associated coagulase-negative staphylococci (CNS). A total of 861 CNS isolates were used in the study, covering 21 different CNS species. The majority of the isolates were previously identified by rpoB gene sequencing (n = 804) and the remainder were identified by sequencing of hsp60 (n = 56) and tuf (n = 1). The genotypic identification was considered the gold standard identification. Using a direct transfer protocol and the existing commercial database, MALDI-TOF mass spectrometry showed a typeability of 96.5% (831/861) and an accuracy of 99.2% (824/831). Using a custom reference spectra expanded database, which included an additional 13 in-house created reference spectra, isolates were identified by MALDI-TOF mass spectrometry with 99.2% (854/861) typeability and 99.4% (849/854) accuracy. Overall, MALDI-TOF mass spectrometry using the direct transfer method was shown to be a highly reliable tool for the identification of bovine-associated CNS. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Methicillin resistant staphylococci associated with bovine mastitis and their zoonotic importance

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S. Vishnupriya

2014-06-01

Full Text Available Aim: The present study was conducted to determine the zoonotic importance of methicillin resistant staphylococci associated with bovine mastitis and their potential role in transmission to animal handlers. Materials and Methods: A total of 158 milk samples from bovine mastitis cases and 126 nasal swabs from the animal handlers were sampled in and around Pondicherry (Southern India. The Presence of Staphylococcal organism was confirmed by PCR amplification using the genus specific primers and among the isolated Staphylococci; methicillin resistance was identified by genetic amplification of mec A methicillin resistant gene. Then the amplified gene from the bacteria expressing the mecA gene (PBP2a (~2kb fragment was further sequenced using four sets of primer pairs and aligned for determining their genetic relatedness between the sequences. Both phenotypic and genotypic analysis was carried out for the six MRS isolates (three bovine and three human in this study. Results: Out of 158 mastitis milk samples; 96 and 19 bovine isolates were found to be positive for Staphylococcal genus specific PCR and methicillin resistant (mecA gene PCR, respectively. Similarly, Out of 126 human nasal swabs, 64 and 13 human isolates were found to be positive for Staphylococcal genus specific PCR and mec A gene PCR, respectively. Among the 160 staphylococcal isolates (Bovine and Human origin; 51 were identified as coagulase-positive staphylococci (CPS and remaining as coagulase-negative staphylococci (CONS. The results obtained in this study revealed the presence of many species of Staphylococci but the predominant species were Staphylococcus aureus and S. epidermidis. The Sequence analysis of the mec A gene of human isolates obtained in this study had a maximum identity (99% -100% with the bovine isolates. Conclusion: The phenotypic and genotypic analysis carried out for the six MRS (Methicillin Resistant Staphylococci isolates in this study were indistinguishable

21 CFR 866.2160 - Coagulase plasma.

Science.gov (United States)

2010-04-01

... DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2160 Coagulase plasma. (a... intended for medical purposes to perform coagulase tests primarily on staphylococcal bacteria. When... staphylococci. Test results are used primarily as an aid in the diagnosis of disease caused by pathogenic...

Mastite subclínica por Staphylococcus coagulase negativa em ovinos de corte

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T.S. Tejada

2012-08-01

Full Text Available Microorganisms that cause mastitis were isolated in a herd of sheep and their sensitivity to antimicrobials was tested. Twenty-one sheep had their mammary glands monitored during lactation. Eighty-eight milk sample from CMT-positive sheep were analyzed in order to isolate the etiologic agent of mastitis. Coagulase negative Staphylococcus were isolated from 29.5% of samples. Ampicillin and penicillin were the antimicrobials with higher number of resistant strains. The importance of coagulase negative staphylococci has been demonstrated, especially S. lentus and S. sciuri as a cause of ovine mastitis.

Coagulase-Negative Staphylococci in Human Milk From Mothers of Preterm Compared With Term Neonates.

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Soeorg, Hiie; Metsvaht, Tuuli; Eelmäe, Imbi; Metsvaht, Hanna Kadri; Treumuth, Sirli; Merila, Mirjam; Ilmoja, Mari-Liis; Lutsar, Irja

2017-05-01

Human milk is the preferred nutrition for neonates and a source of bacteria. Research aim: The authors aimed to characterize the molecular epidemiology and genetic content of staphylococci in the human milk of mothers of preterm and term neonates. Staphylococci were isolated once per week in the 1st month postpartum from the human milk of mothers of 20 healthy term and 49 preterm neonates hospitalized in the neonatal intensive care unit. Multilocus variable-number tandem-repeats analysis and multilocus sequence typing were used. The presence of the mecA gene, icaA gene of the ica-operon, IS 256, and ACME genetic elements was determined by PCR. The human milk of mothers of preterm compared with term neonates had higher counts of staphylococci but lower species diversity. The human milk of mothers of preterm compared with term neonates more often contained Staphylococcus epidermidis mecA (32.7% vs. 2.6%), icaA (18.8% vs. 6%), IS 256 (7.9% vs. 0.9%), and ACME (15.4% vs. 5.1%), as well as Staphylococcus haemolyticus mecA (90.5% vs. 10%) and IS 256 (61.9% vs. 10%). The overall distribution of multilocus variable-number tandem-repeats analysis (MLVA) types and sequence types was similar between the human milk of mothers of preterm and term neonates, but a few mecA-IS 256-positive MLVA types colonized only mothers of preterm neonates. Maternal hospitalization within 1 month postpartum and the use of an arterial catheter or antibacterial treatment in the neonate increased the odds of harboring mecA-positive staphylococci in human milk. Limiting exposure of mothers of preterm neonates to the hospital could prevent human milk colonization with more pathogenic staphylococci.

Occurrence of cfr-mediated multiresistance in staphylococci from veal calves and pigs, from humans at the corresponding farms, and from veterinarians and their family members.

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Cuny, Christiane; Arnold, Phillippe; Hermes, Julia; Eckmanns, Tim; Mehraj, Jaishri; Schoenfelder, Sonja; Ziebuhr, Wilma; Zhao, Qin; Wang, Yang; Feßler, Andrea T; Krause, Gérard; Schwarz, Stefan; Witte, Wolfgang

2017-02-01

This study reports on the emergence of linezolid-resistant coagulase-negative staphylococci (CoNS) containing the multiresistance gene cfr in veal calves and pigs, as well as in humans exposed to these animals. CoNS (Staphylococcus auricularis, Staphylococcus cohnii, Staphylococcus lentus, Staphylococcus kloosii, Staphylococcus sciuri, Staphylococcus simulans), but not Staphylococcus aureus, carrying the gene cfr were detected in samples of 12 out of 52 calves at three farms which had a history of florfenicol use. Nasal swabs from 10 humans living on these farms were negative for cfr-carrying staphylococci. Nasal swabs taken from 142 calves at 16 farms in the same area that did not use florfenicol were also negative for cfr-carrying staphylococci. 14 cfr-carrying CoNS (S. kloosii, S. saprophyticus, S. simulans) were detected in three of eight conventional pig farms investigated. One of 12 humans living on these farms harboured a cfr-carrying S. cohnii. Among the nasal swabs taken from 169 veterinarians from all over Germany, four (2.3%) were positive for cfr-carrying CoNS (three S. epidermidis, one S. saprophyticus), and three (1.1%) of 263 contact persons of this group also harboured cfr-carrying CoNS (one S. epidermidis, two S. saprophyticus). In vitro conjugation of cfr by filter mating to S. aureus 8325-4 was possible for 10 of 34CoNS and the cfr gene was associated with plasmids of 38-40kb. Moreover, a total of 363 humans of a German municipal community were investigated for nasal carriage of cfr-carrying staphylococci to get an idea whether such isolates are disseminated as nasal colonizers in non-hospitalized humans in the community, were all negative. Copyright © 2016 Elsevier B.V. All rights reserved.

Significância clínica de estafilococos coagulase-negativa isolados de recém-nascidos Clinical significance of coagulase-negative staphylococci isolated from neonates

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Maria de Lourdes R.S. Cunha

2002-01-01

Full Text Available Objetivo: avaliar a significância clínica de estafilococos coagulase-negativa (ECN isolados de processos infecciosos em recém-nascidos da unidade neonatal do Hospital das Clínicas da Faculdade de Medicina de Botucatu. Método: as linhagens de ECN isoladas foram identificadas e classificadas em significativas e contaminantes, com base em uma série de dados clínicos e laboratoriais obtidos dos prontuários dos pacientes internados na unidade neonatal. Foram pesquisados os dados referentes a fatores perinatais de risco para infecção, evolução clínica, alterações do hemograma e/ou positividade de proteína C-reativa e antibioticoterapia. Resultados: das 117 linhagens de ECN isoladas, 60 (51,3% foram classificadas como significativas, e 57 (48,7% como contaminantes. Das 54 crianças com infecção por ECN, 43 (79,6% eram prematuras, e 27 (50,0% tiveram peso ao nascimento Conclusões: a maioria dos recém-nascidos com infecção por ECN apresentou fatores predisponentes importantes para a instalação do processo infeccioso, incluindo o peso de nascimento Objective: to evaluate the clinical significance of coagulase-negative staphylococci (CNS isolated from newborns’ infections at Neonatal Unit of Hospital das Clínicas da Faculdade de Medicina de Botucatu. Methods: the CNS strains isolated were identified and classified as clinically significant and contaminant, based on a series of clinical and laboratory data obtained from patients who stayed in the Neonatal Unit. The following data were analyzed: risk factors for infections, clinical evolution, abnormal blood cell counts and/or C-reactive protein e antibiotic therapy. Results: among the 117 CNS strains isolated, 60 (51.3% were classified as significant and 57 (48.7% as contaminant. Among the 54 infants infected by CNS, 43 (79.6% presented very low birthweight (< 1,500g. Most of the infants infected by CNS were submitted to two or more invasive procedures (77.8%, including use of

Mutasynthesis of lincomycin derivatives with activity against drug-resistant staphylococci

Czech Academy of Sciences Publication Activity Database

Ulanová, Dana; Novotná, Jitka; Smutná, Yvona; Kameník, Zdeněk; Gažák, Radek; Šulc, Miroslav; Sedmera, Petr; Kadlčík, Stanislav; Plháčková, Kamila; Janata, Jiří

2010-01-01

Roč. 54, č. 2 (2010), s. 927-930 ISSN 0066-4804 R&D Projects: GA MŠk 2B08064; GA AV ČR IAA500200810 Institutional research plan: CEZ:AV0Z50200510 Keywords : COAGULASE-NEGATIVE STAPHYLOCOCCI * ERYTHROMYCIN RESISTANCE * SUBSTRATE-SPECIFICITY Subject RIV: EE - Microbiology, Virology Impact factor: 4.672, year: 2010

Comparative evaluation of methods for the detection of biofilm formation in coagulase-negative staphylococci and correlation with antibiogram

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Shrestha LB

2018-04-01

Full Text Available Lok Bahadur Shrestha, Narayan Raj Bhattarai, Basudha Khanal Department of Microbiology and Infectious Diseases, B. P. Koirala Institute of Health Sciences, Dharan, Nepal Introduction: Coagulase-negative staphylococci (CNS are normal commensals of human skin and mucous membranes. The objective of the study was to determine the prevalence of CNS among clinical isolates, characterize them up to species level, compare the three conventional methods for detection of biofilm formation, and study their antimicrobial susceptibility pattern.Materials and methods: CNS were obtained from various clinical samples including blood, urine, central venous catheter tips, endotracheal tube aspirate, and pus during a 1-year period (July 1, 2014, to June 30, 2015. Characterization up to species level was done using biochemical tests, and biofilm formation was detected by tube adherence, Congo red agar, and tissue culture plate method. Antimicrobial susceptibility testing was performed following Clinical and Laboratory Standards Institute guidelines.Results: A total of 71 CNS isolates, comprising of seven species were obtained. Staphylococcus epidermidis was the most common species followed by S. saprophyticus and S. haemolyticus. We detected biofilm formation in 71.8% of isolates. Considering the fact that tissue culture plate method is the gold standard, sensitivity of tube adherence method and Congo red agar method was found as 82% and 78%, respectively. The isolates exhibited high resistance toward penicillin (90%, azithromycin (60%, co-trimoxazole (60%, and ceftriaxone (40%, while all were susceptible to vancomycin and linezolid. Biofilm former isolates showed higher resistance than the non-formers.Conclusion: Among 71 CNS isolated, S. epidermidis was the most common isolate followed by S. saprophyticus and S. haemolyticus. Biofilm formation was detected in 71.8% of the isolates. All of the methods were effective in detecting biofilm-producing CNS strains. The

Rapid identification of staphylococci by Raman spectroscopy

Czech Academy of Sciences Publication Activity Database

Rebrošová, K.; Šiler, Martin; Samek, Ota; Růžička, F.; Bernatová, Silvie; Holá, V.; Ježek, Jan; Zemánek, Pavel; Sokolová, J.; Petráš, P.

2017-01-01

Roč. 7, NOV (2017), s. 1-8, č. článku 14846. ISSN 2045-2322 R&D Projects: GA ČR(CZ) GA15-20645S; GA MŠk(CZ) LO1212; GA MŠk ED0017/01/01 Institutional support: RVO:68081731 Keywords : coagulase-negative staphylococci * Raman spectroscopy * rapid identification Subject RIV: BH - Optics, Masers, Lasers OBOR OECD: Optics (including laser optics and quantum optics) Impact factor: 4.259, year: 2016

Nasal carriage of methicillin-resistant coagulase-negative staphylococci in healthy humans is associated with occupational pig contact in a dose-response manner.

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Li, Ling; Chen, Zhiyao; Guo, Dan; Li, Shunming; Huang, Jingya; Wang, Xiaolin; Yao, Zhenjiang; Chen, Sidong; Ye, Xiaohua

2017-09-01

This study aimed to explore the association between occupational pig contact and human methicillin-resistant coagulase-negative staphylococci (MRCoNS) carriage. We conducted a cross-sectional study of pig exposed participants and controls in Guangdong, China, using a multi-stage sampling design. Participants provided a nasal swab for MRCoNS analysis and resulting isolates were tested for antibiotic susceptibility. The dose-response relation was examined using log binomial regression or Poisson regression models. The adjusted prevalence of MRCoNS carriage in pig exposed participants was 1.67 times (95% CI: 1.32-2.11) higher than in controls. The adjusted average number of resistance to different antibiotic classes of MRCoNS isolates from pig exposed participants was 1.67 times (95% CI: 1.46-1.91) higher than those from controls. Notably, we found the frequency and duration of occupational pig contact was associated with increased prevalence and increased number of resistance to different antibiotic classes of MRCoNS in a dose-response manner. When examining these relations by MRCoNS species, there was still evidence of similar exposure-response relations. Additionally, the proportion of tetracycline-resistant and tet(M)-containing MRCoNS isolates was significantly higher in pig exposed participants than in controls. These findings suggested a potential transmission of MRCoNS from livestock to humans by occupational livestock contact, and the presence of phenotypic and genotypic tetracycline resistance may aid in the differentiation of animal origins of MRCoNS isolates. Copyright © 2017 Elsevier B.V. All rights reserved.

Some coagulase-negative Staphylococcus species affect udder health more than others.

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Supré, K; Haesebrouck, F; Zadoks, R N; Vaneechoutte, M; Piepers, S; De Vliegher, S

2011-05-01

A longitudinal study in 3 dairy herds was conducted to profile the distribution of coagulase-negative Staphylococcus (CNS) species causing bovine intramammary infection (IMI) using molecular identification and to gain more insight in the pathogenic potential of CNS as a group and of the most prevalent species causing IMI. Monthly milk samples from 25 cows in each herd as well as samples from clinical mastitis were collected over a 13-mo period. Coagulase-negative staphylococci were identified to the species level using transfer-RNA intergenic spacer PCR. The distribution of CNS causing IMI was highly herd-dependent, but overall, Staphylococcus chromogenes, Staphylococcus xylosus, Staphylococcus cohnii, and Staphylococcus simulans were the most prevalent. No CNS species were found to cause clinical mastitis. The effect of the most prevalent species on the quarter milk somatic cell count (SCC) was analyzed using a linear mixed model, showing that Staph. chromogenes, Staph. simulans, and Staph. xylosus induced an increase in the SCC that is comparable with that of Staphylococcus aureus. Almost all CNS species were able to cause persistent IMI, with Staph. chromogenes causing the most persistent infections. In conclusion, accurate species identification cannot be ignored when studying the effect of CNS on udder health, as the effect on SCC differs between species and species distribution is herd-specific. Staphylococcus chromogenes, Staph. simulans, and Staph. xylosus seem to be the more important species and deserve special attention in further studies. Reasons for herd dependency and possible cow- and quarter-level risk factors should be examined in detail for the different species, eventually leading to cost-benefit analyses for management changes and, if needed, treatment recommendations. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Slime production and antibiotic susceptibility in staphylococci isolated from clinical samples

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Seza Arslan

2007-02-01

Full Text Available A total of 187 isolates from several clinical specimens were identified to species level as 129 Staphylococcus aureus strains and 58 coagulase-negative staphylococci (CNS strains by the API Staph System (Biomerieux. Slime production was detected both by the conventional Christensen's method as well as by the Congo red agar method. Seventy-two strains of staphylococci isolates (38.5% were found to be slime producers by Christensen's test tube method whereas 58 strains (31% were slime positive with Congo red agar method. There was no statistically significant difference between the two methods for the detection of slime production (P > 0.05. Susceptibility of isolates against antimicrobial agents was tested by the disk diffusion method. Staphylococcal species had resistance to one or more antibiotics. Among the various antimicrobial agents, oxacillin (71.1% and erythromycin (47.1% showed higher resistance than most of the agents used against all isolates. Oxacillin resistant S. aureus (ORSA and oxacillin resistant coagulase-negative staphylococci (ORCNS, 97 (75.2% and 36 (62.1% respectively were frequently observed in strains isolated from clinical materials. Among the ORSA strains, two strains were resistant to vancomycin. Moreover, 96 (74.4% of 129 S. aureus strains were positive for blactamase enzyme. However, 78 (81.25% of 96 b-lactamase positive S. aureus strains were b-lactamase positive ORSA isolates, but none of them had vancomycin resistance.

Speciation and Biofilm Production of Coagulase Negative Staphylococcal Isolates from Clinically Significant Specimens and their Antibiogram

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S. S. Vijayasri Badampudi

2016-04-01

Full Text Available Background: Coagulase Negative Staphylococci (CONS are increasingly recognized as significant nosocomial pathogens. Their ability of biofilm formation and multiple drug resistance are causing serious human infections. Aim and Objectives: To isolate, identify, speciate clinically significant CONS from various specimens, to study antibiotic resistance pattern and biofilm production. Material and Methods: Specimens were collected aseptically, processed and identified upto the species level by a simple scheme of tests urease, novobiocin resistance, mannose and mannitol fermentation, ornithine decarboxylase. Antibiotic sensitivity was done with special reference to methicillin resistance. Biofilm formation was detected by Congo Red Agar (CRA method and Tube Method (TM. Results: Study groupOf 100 isolates majority were pus (40, followed by urine (28, blood (16, CSF (5, body fluids (4 and catheter tips and implants (7. The most common species isolated was S. epidermidis (40% followed by S. haemolyticus (26%, S. saprophyticus (15%, S. schleiferi (13%, S. simulans (2%, S. cohnii (2% and S. warneri and S. capitis each 1%. Resistance to penicillin was 91% followed by ampicillin (79%, cotrimoxazole (67%. Methicillin resistance was 72%. Biofilm producers were 69% by CRAmethod and 33% by TM with majority species S. epidermidis (82.5%- CRA and 55%-TM. Biofilm production was significantly associated with MRCONS (p value 0.0036. Control group-Of 30 isolates were S. epidermidis 66.6% followed by S. haemolyticus (16.66%. Biofilm producers were 53.33% by CRA method and 26.65% by TM with majority species S. epidermidis (65%-CRA and 30%-TM.Methicillin resistance was 26.6%. Conclusion: Clinical significance of CONS is increasing day by day, so there is a need for accurate identification to species level and their antibiogram to avoid multidrug resistance. Biofilm producing CONS species pose a risk and CRA method for screening biofilm can be used in all conventional

Modified DNA extraction for rapid PCR detection of methicillin-resistant staphylococci

International Nuclear Information System (INIS)

Japoni, A.; Alborzi, A.; Rasouli, M.; Pourabbas, B.

2004-01-01

Nosocomial infection caused by methicillin-resistant staphylococci poses a serious problem in many countries. The aim of this study was to rapidly and reliably detect methicillin-resistant-staphylococci in order to suggest appropriate therapy. The presence or absence of the methicillin-resistance gene in 115 clinical isolates of staphylococcus aureus and 50 isolates of coagulase negative staphylococci was examined by normal PCR. DNA extraction for PCR performance was then modified by omission of achromopeptadiase and proteinase K digestion, phenol/chloroform extraction and ethanol precipitation. All isolates with Mic>8 μ g/ml showed positive PCR. No differences in PCR detection have been observed when normal and modified DNA extractions have been performed. Our modified DNA extraction can quickly detect methicillin-resistant staphylococci by PCR. The advantage of rapid DNA extraction extends to both reduction of time and cost of PCR performance. This modified DNA extraction is suitable for different PCR detection, when staphylococci are the subject of DNA analysis

Beta-lactamase detection in Staphylococcus aureus and coagulase-negative Staphylococcus isolated from bovine mastitis

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Bruno F. Robles

2014-04-01

Full Text Available The objectives of the study were to evaluate the presence/production of beta-lactamases by both phenotypic and genotypic methods, verify whether results are dependent of bacteria type (Staphylococcus aureus versus coagulase-negative Staphylococcus - CNS and verify the agreement between tests. A total of 200 bacteria samples from 21 different herds were enrolled, being 100 CNS and 100 S. aureus. Beta-lactamase presence/detection was performed by different tests (PCR, clover leaf test - CLT, Nitrocefin disk, and in vitro resistance to penicillin. Results of all tests were not dependent of bacteria type (CNS or S. aureus. Several S. aureus beta-lactamase producing isolates were from the same herd. Phenotypic tests excluding in vitro resistance to penicillin showed a strong association measured by the kappa coefficient for both bacteria species. Nitrocefin and CLT are more reliable tests for detecting beta-lactamase production in staphylococci.

Technical note: a pilot study using a mouse mastitis model to study differences between bovine associated coagulase-negative staphylococci.

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Breyne, K; De Vliegher, S; De Visscher, A; Piepers, S; Meyer, E

2015-02-01

Coagulase-negative staphylococci (CNS) are a group of bacteria classified as either minor mastitis pathogens or commensal microbiota. Recent research suggests species- and even strain-related epidemiological and genetic differences within the large CNS group. The current pilot study investigated in 2 experiments whether a mouse mastitis model validated for bovine Staphylococcus aureus can be used to explore further differences between CNS species and strains. In a first dose titration experiment, a low inoculum dose of S. aureus Newbould 305 (positive control) was compared with increasing inoculum doses of a Staphylococcus chromogenes strain originating from a chronic bovine intramammary infection to a sham-inoculated mammary glands (negative control). In contrast to the high bacterial growth following inoculation with S. aureus, S. chromogenes was retrieved in very low levels at 24 h postinduction (p.i.). In a second experiment, the inflammation inflicted by 3 CNS strains was studied in mice. The host immune response induced by the S. chromogenes intramammary strain was compared with the one induced by a Staphylococcus fleurettii strain originating from cow bedding sawdust and by a S. chromogenes strain originating from a teat apex of a heifer. As expected, at 28 and 48 h p.i., low bacterial growth and local neutrophil influx in the mammary gland were induced by all CNS strains. As hypothesized, bacterial growth p.i. was the lowest for S. fleurettii compared with that induced by the 2 S. chromogenes strains, and the overall immune response established by the 3 CNS strains was less pronounced compared with the one induced by S. aureus. Proinflammatory cytokine profiling revealed that S. aureus locally induced IL-6 and IL-1β but not TNF-α, whereas, overall, CNS-inoculated glands lacked a strong cytokine host response but also induced IL-1β locally. Compared with both other CNS strains, S. chromogenes from the teat apex inflicted a more variable IL-1β response

Evaluation of oxacillin and cefoxitin disks for detection of resistance in coagulase negative staphylococci.

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Souza Antunes, Ana Lúcia; Secchi, Carina; Reiter, Keli Cristine; Rodrigues Perez, Leandro Reus; Peixoto de Freitas, Ana Lúcia; Alves d'Azevedo, Pedro

2007-09-01

Coagulase-negative Staphylococcus spp. was considered nonpathogenic until the emergence of multiresistance and the demonstration of their participation as infectious agents. In Brazil, oxacillin resistance may be present in over 80% of isolates, and the Clinical and Laboratory Standards Institute standardized a disk-diffusion method to predict this resistance in Staphylococcus. The aim of this study was to evaluate the variability among commercial disks of oxacillin (1 microg) and cefoxitin (30 microg) widely used in clinical laboratories of microbiology, compared with mecA gene and minimum inhibitory concentration (MIC) of oxacillin. The use of oxacillin and cefoxitin disks simultaneously allowed the detection of important differences, particularly, in less frequent species such as S. cohnii, S. haemolyticus, S. saprophyticus, and S. sciuri. Disks of cefoxitin of the brand 2 displayed good correlation with the mecA gene (98.7%) and oxacillin MIC (97.8%), while major discrepancies were observed using disks of brand 1. One of the critical points in the diffusion disk test is the quality of the disks: the use of better quality disks associated with molecular methods lead to better results to define the best antibiotic therapy.

Evaluation of oxacillin and cefoxitin disks for detection of resistance in coagulase negative staphylococci

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Ana Lúcia Souza Antunes

2007-09-01

Full Text Available Coagulase-negative Staphylococcus spp. was considered nonpathogenic until the emergence of multiresistance and the demonstration of their participation as infectious agents. In Brazil, oxacillin resistance may be present in over 80% of isolates, and the Clinical and Laboratory Standards Institute standardized a disk-diffusion method to predict this resistance in Staphylococcus. The aim of this study was to evaluate the variability among commercial disks of oxacillin (1 µg and cefoxitin (30 µg widely used in clinical laboratories of microbiology, compared with mecA gene and minimum inhibitory concentration (MIC of oxacillin. The use of oxacillin and cefoxitin disks simultaneously allowed the detection of important differences, particularly, in less frequent species such as S. cohnii, S. haemolyticus, S. saprophyticus, and S. sciuri. Disks of cefoxitin of the brand 2 displayed good correlation with the mecA gene (98.7% and oxacillin MIC (97.8%, while major discrepancies were observed using disks of brand 1. One of the critical points in the diffusion disk test is the quality of the disks: the use of better quality disks associated with molecular methods lead to better results to define the best antibiotic therapy.

Antimicrobial resistance and detection of the mecA gene besides enterotoxin-encoding genes among coagulase-negative Staphylococci isolated from clam meat of Anomalocardia brasiliana.

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Batista, Jacqueline Ellen Camelo; Ferreira, Ewerton Lucena; Nascimento, Danielle Cristina de Oliveira; Ventura, Roberta Ferreira; de Oliveira, Wagner Luis Mendes; Leal, Nilma Cintra; Lima-Filho, José Vitor

2013-12-01

The marine clam Anomalocardia brasiliana is a candidate as a sentinel animal to monitor the contamination levels of coliforms in shellfish-harvesting areas of Brazil's northeastern region. The aim of the present study was to search enterotoxin-encoding genes plus the mecA gene among coagulase-negative staphylococci (CNS) isolates from shellfish meats of A. brasiliana. The specimen clam (n=48; 40 clams per sample) was collected during low tide in the bay area of Mangue Seco from April through June 2009, and random samples of chilled and frozen shelled clam meat (n=33; 250 g per sample) were obtained from retail shops from January through March 2012. Seventy-nine CNS isolates were identified, including Staphylococcus xylosus, S. cohnii spp. urealyticus, S. sciuri, and S. lentus. A high percentage of isolates resistant to erythromycin (58.5%), penicillin (51.2%), and tetracycline (43.9%), and the fluoroquinolones levofloxacin (39%) and ciprofloxacin (34.1%) were recorded from those environmental samples. Isolates from retail shops were particularly resistant to oxacillin (55.3%) and penicillin (36.8%). All CNS resistant to oxacillin and/or cefoxitin were positive for the presence of the mecA gene, but phenotypically susceptible to vancomycin. Also, the enterotoxin-encoding genes seg and seh were detected through multiplex-polymerase chain reaction in 77.7% and 88.8% of the isolates from environmental samples, versus 90.5% and 100% of the isolates from retail shops, respectively. The data reveal the risk to public health due to consuming raw or undercooked shellfish containing enterotoxigenic plus methicillin-resistant CNS.

Comparison of growth on mannitol salt agar, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, VITEK® 2 with partial sequencing of 16S rRNA gene for identification of coagulase-negative staphylococci.

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Ayeni, Funmilola A; Andersen, Camilla; Nørskov-Lauritsen, Niels

2017-04-01

Mannitol salt agar (MSA) is often used in resources' limited laboratories for identification of S. aureus however, coagulase-negative staphylococci (CoNS) grows and ferments mannitol on MSA. 171 strains of CoNS which have been previously misidentified as S. aureus due to growth on MSA were collected from different locations in Nigeria and two methods for identification of CoNS were compared i.e. ViTEK 2 and MALDI-TOF MS with partial 16S rRNA gene sequencing as gold standard. Partial tuf gene sequencing was used for contradicting identification. All 171 strains (13 species) grew on MSA and ferments mannitol. All tested strains of S. epidermidis, S. haemolyticus, S. nepalensis, S. pasteuri, S. sciuri,, S. warneri, S. xylosus, S. capitis were correctly identified by MALDI-TOF while variable identification were observed in S. saprophyticus and S. cohnii (90%, 81%). There was low identification of S. arlettae (14%) while all strains of S. kloosii and S. gallinarum were misidentified. There is absence of S. gallinarum in the MALDI-TOF database at the period of this study. All tested strains of S. epidermidis, S. gallinarum, S. haemolyticus, S. sciuri,, S. warneri, S. xylosus and S. capitis were correctly identified by ViTEK while variable identification were observed in S. saprophyticus, S. arlettae, S. cohnii, S. kloosii, (84%, 86%, 75%, 60%) and misidentification of S. nepalensis, S. pasteuri. Partial sequencing of 16S rRNA gene was used as gold standard for most strains except S. capitis and S. xylosus where the two species were misidentified by partial sequencing of 16S rRNA contrary to MALDI-TOF and ViTEK identification. Tuf gene sequencing was used for correct identification. Characteristic growth on MSA for CoNS is also identical to S. aureus growth on the media and therefore, MSA could not differentiate between S. aureus and CoNS. The percentage accuracy of ViTEK was better than MALDI-TOF in identification of CoNS. Although partial sequencing of

Public transport as a reservoir of methicillin-resistant staphylococci.

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Stepanović, S; Cirković, I; Djukić, S; Vuković, D; Svabić-Vlahović, M

2008-10-01

The aim of this study was to explore the occurrence of methicillin-resistant staphylococci in a large urban public transport system. Samples were taken from hand rails, which passengers hold onto when they are standing. In total, 1400 swabs taken from 55 vehicles (trolleybuses, trams and buses) were examined. As many as 30.1% samples were positive for the presence of methicillin-resistant coagulase-negative staphylococci (MRCoNS), but none for methicillin-resistant Staphylococcus aureus (MRSA). MRCoNS were isolated from all 55 vehicles. Nearly 50% of MRCoNS isolates displayed resistance not only to beta-lactams, but at least to two or more other classes of antimicrobials as well. This study demonstrated widespread occurrence of MRCoNS on hand rails in public transport vehicles. MRSA was not detected. The recovery of methicillin-resistant staphylococci from public transport system implies a potential risk for transmission of these bacteria in an out-hospital environment.

Prevalence of the antibiotic resistance genes in coagulase-positive- and negative-Staphylococcus in chicken meat retailed to consumers

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Kamelia Mahmoud Osman

2016-11-01

Full Text Available The use of antibiotics in farm management (growing crops and raising animals has become a major area of concern. Its implications is the consequent emergence of antibiotic resistant bacteria (ARB and accordingly their access into the human food chain with passage of antibiotic resistance genes (ARG to the normal human intestinal microbiota and hence to other pathogenic bacteria causative human disease. Therefore, we pursued in this study to unravel the frequency and the quinolone resistance determining region, mecA and cfr genes of methicillin-susceptible Staphylococcus aureus (MSSA, methicillin-resistant S. aureus (MRSA, methicillin-resistant coagulase-negative staphylococci (MRCNS and methicillin-susceptible coagulase-negative staphylococci (MSCNS isolated from the retail trade of ready-to-eat raw chicken meat samples collected during one year and sold across the Great Cairo area. The 50 Staphylococcus isolated from retail raw chicken meat were analyzed for their antibiotic resistance phenotypic profile on 12 antibiotics (penicillin, oxacillin, methicillin, ampicillin-sulbactam, erythromycin, tetracycline, clindamycin, gentamicin, ciprofloxacin, chloramphenicol, sulfamethoxazole-trimethoprim and vancomycin and their endorsement of the quinolone resistance determining region, mecA and cfr genes. The isolation results revealed 50 isolates, CPS (14 and CNS (36, representing ten species (S. aureus, S. hyicus, S. epidermedius, S. lugdunensis, S. haemolyticus, S. hominus, S. schleiferi, S. cohnii, S. intermedius and S. lentus. Twenty seven isolates were methicillin-resistant. Out of the characterized 50 staphylococcal isolates, three were MRSA but only 2/3 carried the mecA gene. The ARG that bestows resistance to quinolones, β-lactams, macrolides, lincosamides and streptogramin B (MLS(B in MRSA and MR-CNS were perceived. According to the available literature, the present investigation was a unique endeavor into the identification of the quinolone

Prevalence of the Antibiotic Resistance Genes in Coagulase-Positive-and Negative-Staphylococcus in Chicken Meat Retailed to Consumers.

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Osman, Kamelia; Badr, Jihan; Al-Maary, Khalid S; Moussa, Ihab M I; Hessain, Ashgan M; Girah, Zeinab M S Amin; Abo-Shama, Usama H; Orabi, Ahmed; Saad, Aalaa

2016-01-01

The use of antibiotics in farm management (growing crops and raising animals) has become a major area of concern. Its implications is the consequent emergence of antibiotic resistant bacteria (ARB) and accordingly their access into the human food chain with passage of antibiotic resistance genes (ARG) to the normal human intestinal microbiota and hence to other pathogenic bacteria causative human disease. Therefore, we pursued in this study to unravel the frequency and the quinolone resistance determining region, mec A and cfr genes of methicillin-susceptible Staphylococcus aureus (MSSA), methicillin-resistant S. aureus (MRSA), methicillin-resistant coagulase-negative staphylococci (MRCNS) and methicillin-susceptible coagulase-negative staphylococci (MSCNS) isolated from the retail trade of ready-to-eat raw chicken meat samples collected during 1 year and sold across the Great Cairo area. The 50 Staphylococcus isolated from retail raw chicken meat were analyzed for their antibiotic resistance phenotypic profile on 12 antibiotics (penicillin, oxacillin, methicillin, ampicillin-sulbactam, erythromycin, tetracycline, clindamycin, gentamicin, ciprofloxacin, chloramphenicol, sulfamethoxazole-trimethoprim, and vancomycin) and their endorsement of the quinolone resistance determining region, mec A and cfr genes. The isolation results revealed 50 isolates, CPS (14) and CNS (36), representing ten species ( S. aureus, S. hyicus, S. epidermedius, S. lugdunensis, S. haemolyticus, S. hominus, S. schleiferi, S. cohnii, S. intermedius , and S. lentus ). Twenty seven isolates were methicillin-resistant. Out of the characterized 50 staphylococcal isolates, three were MRSA but only 2/3 carried the mec A gene. The ARG that bestows resistance to quinolones, β-lactams, macrolides, lincosamides, and streptogramin B [MLS( B )] in MRSA and MR-CNS were perceived. According to the available literature, the present investigation was a unique endeavor into the identification of the quinolone

Estudo da produção de beta -lactamase e sensibilidade às drogas em linhagens de estafilococos coagulase-negativos isolados de recém-nascidos Study of production of beta-lactamase and drugs susceptibility in strains of coagulase-negative staphylococci isolated of neonates

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Maria de Lourdes Ribeiro de Souza da Cunha

2002-01-01

Full Text Available Os estafilococos coagulase-negativos (ECN, embora reconhecidos como saprófitas por muito tempo, têm emergido como agentes etiológicos de uma série de infecções, sendo atualmente os principais responsáveis por sepse em UTI neonatal. Tendo em vista estas características, este estudo objetivou a identificação de estafilococos coagulase-negativos isolados de processos infecciosos em recém-nascidos, bem como a determinação da produção de beta-lactamase e sensibilidade às drogas pelas linhagens isoladas. O Staphylococcus epidermidis foi a espécie mais freqüentemente isolada (77,8%. O estudo da produção de beta-lactamase revelou esta característica na maioria das linhagens de ECN isoladas (71,8%. As linhagens de ECN mostraram, ainda, resistência múltipla aos antibióticos utilizados, com 63,2% dos isolados apresentando resistência a cinco ou mais drogas. A elevada transmissibilidade de plasmídios entre estas linhagens e o uso abusivo de drogas antimicrobianas têm-se constituído em importantes fatores na seleção de amostras multirresistentes e na transferência de genes de resistência.Although coagulase-negative staphylococci (CNS have been recognized as saprophytes for a long time, they had emerged as etiologic agents of infections. They have currently been the most frequently isolated pathogen in sepsis in neonatal intensive care unit (NICU. This study aimed the identification of CNS strains isolated from newborns' infections and to determination of beta-lactamase and drugs susceptibility. Staphylococcus epidermidis was the most frequently isolated species (77,8%. The study of the beta-lactamase production revealed this characteristic in the most of the strains of CNS isolated (71,8%. The strains isolated in this study presented multiple resistance to the antibiotics tested, with 63,2% of isolates presenting resistance to five or more drugs. The high transmissibility of plasmids among those strains and the abusive use of

[Resistance to heavy metals in ruminal staphylococci].

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Lauková, A

1994-01-01

Ruminal, coagulase-negative, urease and bacteriocin-like substances producing staphylococci were screened for their heavy metal ions and antibiotics resistance. All strains tested were resistant to disodium arsenate at a minimal inhibition concentration (MIC > 5 g/l) and cadmium sulphate (MIC > 4 g/l). MIC = 50-60 mg/l was determined in eight staphylococci screened in mercury chloride resistance test (Tab. I). Silver nitrate resistance was detected in seven of the bacteria used (MIC = 40-50 mg/l). All strains were novobiocin resistant. Staphylococcus cohnii subsp. urealyticum SCU 40 was found as a strain with resistance to all heavy metal ions and 5 antibiotics (Tab. II). In addition, this strain produced bacteriocin-like substance which inhibited growth of six indicators of different origin (Tab. II). The most of staphylococci were detected as heavy metal ion polyresistant strains and antibiotic polyresistant strains producing antimicrobial substances with inhibition effects against at least one indicator of different origin. These results represent the first information on heavy metal ion resistance in ruminal bacteria. They also show relation or coresistance between heavy metal ions and antibiotics. Resulting from this study, staphylococci can be used as a bioindicator model for animal environmental studies. In addition, it can be used for specific interactions studies within the framework of ruminal bacterial ecosystem and also mainly with regard to molecular genetic studies.

Clinical characteristics and persistence of bovine mastitis caused by different species of coagulase-negative staphylococci identified with API or AFLP

DEFF Research Database (Denmark)

Taponen, S.; Simojoki, H.; Haveri, M.

2006-01-01

The coagulase-negative staphylococcal species causing mastitis in lactating cattle were identified and possible differences in the clinical characteristics or persistence of mastitis caused by different CNS were evaluated. The effect of antimicrobial treatment was also assessed. In addition, AFLP...... of these species. Approximately half of the mastitis cases were clinical, and in the majority clinical signs were mild. The severity and persistence of intramammary infection were unaffected by CNS species. Fifty-nine percent of the quarter cases were treated with antimicrobials, and the rest were left without...... treatment. Mastitis due to P-lactamase-negative CNS was treated with penicillin G and that due to beta-lactamase-positive CNS with cloxacillin. Nineteen percent of the isolates were P-lactamase-positive. The bacterial cure rate for quarters treated with antimicrobials was high, 85.9%, as opposed to only 45...

Bacteremias por Staphylococcus coagulase negativos oxacilina resistentes em um hospital escola na cidade de Santa Maria, Estado do Rio Grande do Sul Oxacillin-resistant coagulase-negative Staphylococci bacteremia at a teaching hospital in Santa Maria, State of Rio Grande do Sul, Brazil

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Fabiane Rigatti

2010-12-01

Full Text Available INTRODUÇÃO: Neste estudo, objetivou-se caracterizar a prevalência e o perfil de suscetibilidade de cepas de Staphylococcus coagulase negatives resistentes à oxacilina isoladas de culturas de sangue, em um hospital escola, localizado na Cidade de Santa Maria. Além disso, buscou-se comparar ao teste genotípico de referência, diferentes metodologias fenotípicas para a caracterização da resistência mediada pelo gene mecA. MÉTODOS: Após identificação (MicroScan® - Siemens, os isolados foram submetidos a testes de sensibilidade antimicrobiana a partir da difusão do disco e automação (MicroScan® - Siemens. A presença do gene mecA foi evidenciada através da técnica molecular de reação em cadeia da polimerase. RESULTADOS: A espécie prevalente foi Staphylococcus epidermidis (67%. O gene mecA foi detectado em 90% das cepas e conforme análise dos perfis de sensibilidade, observou-se um índice elevado de resistência a várias classes de antimicrobianos. Contudo, todos os isolados mostraram-se uniformemente sensíveis à vancomicina e tigeciclina. O disco de cefoxitina foi a metodologia fenotípica que melhor correlacionou-se com o padrão ouro. CONCLUSÕES: A análise da significância clínica de SCN isolados de hemoculturas e a detecção precisa da resistência à oxacilina representam fatores decisivos para a instituição correta da antibioticoterapia. Apesar da vancomicina constituir o tratamento usual na maioria dos hospitais brasileiros, tem a redução de seu emprego recomendada.INTRODUCTION: This study aimed to characterize the prevalence and susceptibility profile to oxacillin-resistant Coagulase-negative Staphylococci strains isolated from blood cultures in a teaching hospital, located in Santa Maria, RS. In addition, different methodologies for phenotypic characterization of mecA-mediated oxacillin resistance were compared with genotypic reference testing. METHODS: After identification (MicroScan® - Siemens, the

In vitro efficacy and pharmacodynamic indices for antibiotics against coagulase-negative staphylococcus endophthalmitis isolates.

Science.gov (United States)

Harper, Tom; Miller, Darlene; Flynn, Harry W

2007-05-01

To compare pharmacodynamic indices and minimal inhibitory concentrations for vancomycin, gatifloxacin, moxifloxacin, linezolid, and combined quinupristin and dalfopristin for historic and current human coagulase-negative staphylococcus (CoNS) endophthalmitis isolates. Experimental study. Fifty-nine CoNS endophthalmitis isolates retrieved from patients at the Bascom Palmer Eye Institute from 1993 through 2006. Coagulase-negative staphylococcal endophthalmitis isolates were recovered from the microbiology specimen bank, rehydrated, and processed for susceptibility testing using standard microbiological protocols. E tests were used to determine and compare mean inhibitory concentration for 50% of isolates (MIC50) and mean inhibitory concentration for 90% of isolates (MIC90) values. Peak concentration (C(max)) was defined as the maximum attainable aqueous concentration using topical or oral therapy, or both. The MIC50 and MIC90 values for each antibiotic are the minimum concentrations that inhibit 50% and 90% of CoNS endophthalmitis isolates, respectively. Significance was determined by the McNemar test. Pharmacodynamic indices (C(max)/MIC) were calculated using determined MIC values and published intraocular drug concentrations for topical and oral dosing. The pharmacodynamic index was defined as the achievable aqueous humor concentration of an antibiotic divided by the concentration of the antibiotic required to inhibit a specified percentage of microbiologic isolates. Pharmacodynamic indices for new and conventional antibiotics. General in vitro susceptibility patterns in descending order were vancomycin (100%), linezolid (100%), quinupristin and dalfopristin (98%), moxifloxacin (48%), and gatifloxacin (47%). The corresponding MIC50 and MIC90 values were vancomycin, 2 microg/ml and 3 microg/ml, respectively; linezolid, 1 microg/ml and 4 microg/ml; quinupristin and dalfopristin, 0.25 microg/ml and 0.5 microg/ml; moxifloxacin, 0.75 microg/ml and > or =32 microg

Antimicrobial susceptibility and presence of resistance genes in staphylococci from poultry

DEFF Research Database (Denmark)

Aarestrup, Frank Møller; Agersø, Yvonne; Ahrens, Peter

2000-01-01

of conventional biochemical testing and 16S rDNA sequencing. The most common species were Staphylococcus aureus (83), Staphylococcus hyicus (11), Staphylococcus xylosus (9) and Staphylococcus cohnii (6). The isolates were susceptible to most antimicrobials tested. A high frequency of S. aureus (30%) was resistant...... to ciprofloxacin. Only six (7%) S. aureus isolates and one Staphylococcus saprophyticus were penicillin resistant. Resistance to sulphamethoxazole was observed among 16 (19%) of S. aureus isolates and two coagulase negative staphylococci (CNS). Twenty (24%) of the S. aureus isolates were resistant to erythromycin...

Biotechnological Methods for Precise Diagnosis of Methicillin Resistance in Staphylococci

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Aija Zilevica

2005-04-01

Full Text Available Antimicrobial resistance is one of the most urgent problems in medicine nowadays. The purpose of the study was to investigate the microorganisms resistant to first-line antimicrobials, including gram-positive cocci, particularly the methicillin-resistant Staphylococcus aureus and coagulase-negative Staphylococci, the major agents of nosocomial infections. Owing to the multi-resistance of these agents, precise diagnosis of the methicillin resistance of Staphylococci is of greatest clinical importance. It is not enough to use only conventional microbiological diagnostic methods. Biotechnological methods should be also involved. In our studies, the following methicillin resistance identification methods were used: the disk diffusion method, detection of the mecA gene by PCR, E-test and Slidex MRSA test. For molecular typing, PFGL, RAPD tests and detection of the coa gene were used. All the MRS strains were multiresistant to antibacterials. No vancomycine resistance was registered.

Occurrence of bovine mastitis and isolation of Staphyloccocus ...

African Journals Online (AJOL)

Occurrence of bovine mastitis and isolation of Staphyloccocus species from ... the samples that were positive for CMT were found to be culture positive and out of ... S. aureus and 12.3% (12/97) were coagulase-negative staphylococci (CONS).

Short communication: Species group-specific predictors at the cow and quarter level for intramammary infection with coagulase-negative staphylococci in dairy cattle throughout lactation.

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De Visscher, A; Piepers, S; Supré, K; Haesebrouck, F; De Vliegher, S

2015-08-01

Coagulase-negative staphylococci (CNS) are frequently isolated from quarters with subclinical mastitis, teat apices, and the cows' environment. Virulence, ecology, epidemiological behavior, and effect on udder health vary between different CNS species. Staphylococcus chromogenes, Staph. simulans, and Staph. xylosus are frequently present in milk and have a more substantial effect on quarter milk somatic cell count than other species. Therefore, these species are considered the "more relevant" CNS. As species-specific factors associated with CNS intramammary infection (IMI) have not yet been identified and susceptibility for IMI differs between cows and quarters, this study aimed to identify predictors for CNS IMI at the cow and quarter level (some of them changing over time) with a specific focus on the aforementioned more relevant CNS. Precise data were available from a longitudinal study (3,052 observations from 344 quarters from 86 dairy cows belonging to 3 commercial dairy herds). All CNS were molecularly identified to the species level, and multivariable, multilevel logistic regression models taking into account the longitudinal nature of the data, were fit to study the likelihood of infection. Staphylococcus chromogenes, Staph. xylosus, and Staph. cohnii were the most frequently isolated species from CNS IMI in older cows, whereas Staph. chromogenes, Staph. xylosus, and Staph. simulans were the main species found in IMI in heifers. Quarters from heifers (as opposed to multiparous cows), from heifers and multiparous cows in third or fourth month in lactation (as opposed to early lactation, <60 d in milk), and with an increasing quarter milk SCC were more likely to be infected with the more relevant CNS species. Quarter milk SCC was identified as the sole statistically significant predictor for IMI with other CNS species, although the size of the effect was lower [odds ratio of 1.6 (1.4-1.9) vs. 2.1 (1.8-2.5)] than the effect for IMI with the more relevant CNS

Process-driven bacterial community dynamics are key to cured meat colour formation by coagulase-negative staphylococci via nitrate reductase or nitric oxide synthase activities.

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Sánchez Mainar, María; Leroy, Frédéric

2015-11-06

The cured colour of European raw fermented meats is usually achieved by nitrate-into-nitrite reduction by coagulase-negative staphylococci (CNS), subsequently generating nitric oxide to form the relatively stable nitrosomyoglobin pigment. The present study aimed at comparing this classical curing procedure, based on nitrate reductase activity, with a potential alternative colour formation mechanism, based on nitric oxide synthase (NOS) activity, under different acidification profiles. To this end, meat models with and without added nitrate were fermented with cultures of an acidifying strain (Lactobacillus sakei CTC 494) and either a nitrate-reducing Staphylococcus carnosus strain or a rare NOS-positive CNS strain (Staphylococcus haemolyticus G110), or by relying on the background microbiota. Satisfactory colour was obtained in the models prepared with added nitrate and S. carnosus. In the presence of nitrate but absence of added CNS, however, cured colour was only obtained when L. sakei CTC 494 was also omitted. This was ascribed to the pH dependency of the emerging CNS background microbiota, selecting for nitrate-reducing Staphylococcus equorum strains at mild acidification conditions but for Staphylococcus saprophyticus strains with poor colour formation capability when the pH decrease was more rapid. This reliance of colour formation on the composition of the background microbiota was further explored by a side experiment, demonstrating the heterogeneity in nitrate reduction of a set of 88 CNS strains from different species. Finally, in all batches prepared with S. haemolyticus G110, colour generation failed as the strain was systematically outcompeted by the background microbiota, even when imposing milder acidification profiles. Thus, when aiming at colour formation through CNS metabolism, technological processing can severely interfere with the composition and functionality of the meat-associated CNS communities, for both nitrate reductase and NOS activities

Role of Enterotoxin-Producing Staphylococci in Zoonotic Infections in Iran

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Abdolmajid Ghasemian

2018-05-01

Full Text Available Context: Staphylococci spp, are enterotoxin-producing zoonotic agents causing a variety of infections such as mastitis in animals and wound bite infections in humans. This review was conducted to determine the prevalence of Staphylococci infections especially to uncover enterotoxin-producing species in Iran. Evidence acquisition: for this review, words of "Staphylococcus", "zoonotic", "prevalence", "animals", "human" and "Iran" were searched in the internet engines such as Google Scholar, PubMed, Google, Science Direct and so on. Patients with no history of contact with animals were also included in the study for comparison aims. Both veterinary and human coagulase positive isolates were included. Data was analyzed with Graph Pad Prism 6, meta-analysis section. A total of 20 previous studies (450 clinical samples were found. S. intermedius was the predominant isolate identified in veterinary sources. Other coagulase positive spp such as S. hycus and S. simulans were isolated with lower prevalence, but S. delphini has not been detected. Conclusion: S. intermedius was the most isolate identified in veterinary sources with potential of causing infections in humans. Other coagulase positive spp such as S. hycus and S. simulans were isolated with lower prevalence, but S. delphini was not detected.

Comparison of four methods for rapid identification of Staphylococcus aureus directly from BACTEC 9240 blood culture system.

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Ozen, N S; Ogunc, D; Mutlu, D; Ongut, G; Baysan, B O; Gunseren, F

2011-01-01

Differentiation of Staphylococcus aureus (S. aureus) from coagulase-negative staphylococci is very important in blood stream infections. Identification of S. aureus and coagulase-negative staphylococci (CoNS) from blood cultures takes generally 18-24 h after positive signaling on continuously monitored automated blood culture system. In this study, we evaluated the performance of tube coagulase test (TCT), slide agglutination test (Dry Spot Staphytect Plus), conventional polymerase chain reaction (PCR) and LightCycler Staphylococcus MGrade kit directly from blood culture bottles to achieve rapid identification of S. aureus by using the BACTEC 9240 blood culture system. A total of 129 BACTEC 9240 bottles growing gram-positive cocci suggesting Staphylococci were tested directly from blood culture broths (BCBs) with TCT, Dry Spot Staphytect Plus, conventional PCR and LightCycler Staphylococcus MGrade kit for rapid identification of S. aureus. The sensitivities of the tests were 99, 68, 99 and 100%, respectively. Our results suggested that 2 h TCT was found to be simple and inexpensive method for the rapid identification of S. aureus directly from positive blood cultures.

The role of staphylococci in subclinical mastitis of cows and lytic phage isolation against to Staphylococcus aureus

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Aliye Gulmez Saglam

2017-12-01

Full Text Available Aim: This study was conducted to determine the role of Staphylococcus in the formation of subclinical mastitis in cows and to isolate the phage against isolated Staphylococcus aureus strains. Materials and Methods: In this study, 400 milk cows were screened by California Mastitis Test (CMT for subclinical mastitis and 235 udders of 96 cows, which were determined to be positive, were evaluated for Staphylococcus. Milk samples were evaluated using conventional and molecular methods. In addition, phage isolation studies were performed against S. aureus strains causing mastitis. Results: At the result of cultural examination, of 235 milk samples that were found as positive for mastitis by CMT, a total of 117 (49.7% Staphylococcus spp. were isolated as a distribution of 74 (63.24% coagulase-positive staphylococci and 43 (36.75% coagulase-negative staphylococci. Of these isolates, 76 (64.95% were characterized as S. aureus both conventional and molecular techniques. Lytic bacteriophages against two S. aureus strains which were isolated from mastitic milk samples were obtained from wastewater samples. Conclusion: The results of this study show that a significant portion of subclinical mastitis was formed by staphylococci. In addition, phage isolation against S. aureus strains isolated can be considered as one of the steps to be applied in the prophylaxis and treatment of such infections.

Comparison of slime-producing coagulase-negative Staphylococcus colonization rates on vinyl and ceramic tile flooring materials.

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Yazgi, H; Uyanik, M H; Ayyildiz, A

2009-01-01

This study investigated the colonization of slime-producing coagulase-negative Staphylococcus (CoNS) in 80 patient wards in Turkey (40 vinyl and 40 ceramic tile floors). A total of 480 samples that included 557 CoNS isolates were obtained. Slime production was investigated with the Christensen method and methicillin-susceptibility was tested by the disk-diffusion method. There was a significant difference in the percentage of slime-producing CoNS isolates on vinyl (12.4%) versus ceramic tile flooring (4.4%). From vinyl flooring, the percentage of slime producing methicillin-resistant CoNS (MRCoNS) (8.9%) was significantly higher than for methicillin-sensitive CoNS (MSCoNS) (3.6%), whereas there was no difference from ceramic tile flooring (2.5% MRCoNS versus 1.8% MSCoNS). The most commonly isolated slime-producing CoNS species was S. epidermidis on both types of flooring. It is concluded that vinyl flooring seems to be a more suitable colonization surface for slime-producing CoNS than ceramic tile floors. Further studies are needed to investigate bacterial strains colonized on flooring materials, which are potential pathogens for nosocomial infections.

Characterization of coagulase-negative staphylococcus species from cows' milk and environment based on bap, icaA, and mecA genes and phenotypic susceptibility to antimicrobials and teat dips.

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Piessens, V; De Vliegher, S; Verbist, B; Braem, G; Van Nuffel, A; De Vuyst, L; Heyndrickx, M; Van Coillie, E

2012-12-01

The aim of this study was to investigate whether the main coagulase-negative staphylococci (CNS) species involved in bovine intramammary infections (IMI) possess specific characteristics that promote colonization of the udder. Virulence markers associated with biofilm formation, antimicrobial resistance, and biocide tolerance were compared between typically contagious CNS species (Staphylococcus chromogenes, Staphylococcus epidermidis, Staphylococcus haemolyticus, and Staphylococcus simulans) and those rarely causing IMI (Staphylococcus sciuri, Staphylococcus equorum, and others) to find possible associations with pathogenicity. Coagulase-negative staphylococci isolates (n=366) belonging to 22 different species were analyzed by PCR for the presence of the biofilm-associated genes bap and icaA, and the methicillin resistance gene mecA. A selection of 82 isolates was additionally tested for their susceptibility to 5 antibiotics and 2 commercial teat dip products. Minimum inhibitory concentrations of antimicrobials were determined by Etest (AB bioMérieux, Marcy l'Etoile, France), and a microdilution method was optimized to determine minimum biocidal concentrations of teat dips. The bap, icaA, and mecA genes were detected significantly more in isolates from CNS species typically living in the cows' environment than in isolates from IMI-causing species. Antimicrobial resistance was mainly against erythromycin (23%) or oxacillin (16%), and was detected more often in the environmental species. The isolates least susceptible to the teat dips belonged to the IMI-causing species Staph. chromogenes and Staph. simulans. We concluded that carriage of biofilm genes and antimicrobial resistance were not associated with the ability to colonize the mammary gland because free-living CNS species constituted a more significant reservoir of biofilm and resistance determinants than did IMI-causing species. In contrast, increased tolerance to biocides may favor the establishment of

Characterization of Staphylococcus spp. strains in milk from buffaloes with mastitis in Brazil: the need to identify to species level to avoid misidentification

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V. Coimbra-e-Souza

Full Text Available ABSTRACT Mastitis is an inflammation of the mammary gland that affects dairy cattle worldwide causing economic losses. Coagulase-negative staphylococci (CNS are the predominant cause of this type of infection. We have recently showed that coagulase-positive staphylococci could be misidentified. So, the aim of this study was to characterize the Staphylococcus spp. strains initially classified as coagulase-negative Staphylococci, isolated from buffalo with subclinical mastitis. Milk of buffaloes with mastitis in herds was collected and 9 strains were identified as CNS by phenotypic tests. Molecular methodologies latter identified the strains as coagulase-negative Staphylococcus chromogenes (5, coagulase-positive Staphylococcus hyicus (2 and coagulase-positive Staphylococcus aureus (2. Our results strongly support the need to identify the isolates to a species level in order to avoid misidentification and to be aware of the classification using the coagulase test alone.

Occurrence, species distribution, antimicrobial resistance and clonality of methicillin- and erythromycin-resistant staphylococci in the nasal cavity of domestic animals

DEFF Research Database (Denmark)

Bagcigil, Funda A.; Moodley, Arshnee; Baptiste, Keith E.

2007-01-01

beta-Lactams and macrolides are important antibiotics for treatment of staphylococcal infections in both humans and animals. The aim of the study was to investigate the occurrence, species distribution and clonality of methicillin and erythromycin-resistant staphylococci in the nasal cavity of dogs......, horses, pigs, and cattle in Denmark. Nasal swabs were collected from a total of 400 animals, including 100 individuals of each species. Methicillin and erythromycin-resistant staphylococci were isolated on selective media, identified by 16S rDNA sequencing, and typed by pulsed field gel electrophoresis...... (PFGE). Methicillin-resistant coagulase-negative staphylococci (MRCoNS) harbouring mecA were isolated from horses (50%) and dogs (13%), but not from food animals. The species identified were S. haemolyticus (n = 21), S. vitulinus (n = 19), S. sciuri (n = 13), S. epidermidis (n = 8), and S. warneri (n...

Characterization of staphylococci in urban wastewater treatment plants in Spain, with detection of methicillin resistant Staphylococcus aureus ST398

International Nuclear Information System (INIS)

Gómez, Paula; Lozano, Carmen; Benito, Daniel; Estepa, Vanesa; Tenorio, Carmen; Zarazaga, Myriam; Torres, Carmen

2016-01-01

The objective of this study was to determine the prevalence of Staphylococcus in urban wastewater treatment plants (UWTP) of La Rioja (Spain), and to characterize de obtained isolates. 16 wastewater samples (8 influent, 8 effluent) of six UWTPs were seeded on mannitol-salt-agar and oxacillin-resistance-screening-agar-base for staphylococci and methicillin-resistant Staphylococcus aureus recovery. Antimicrobial susceptibility profile was determined for 16 antibiotics and the presence of 35 antimicrobial resistance genes and 14 virulence genes by PCR. S. aureus was typed by spa, agr, and multilocus-sequence-typing, and the presence of immune-evasion-genes cluster was analyzed. Staphylococcus spp. were detected in 13 of 16 tested wastewater samples (81%), although the number of CFU/mL decreased after treatment. 40 staphylococci were recovered (1–5/sample), and 8 of them were identified as S. aureus being typed as (number of strains): spa-t011/agr-II/ST398 (1), spa-t002/agr-II/ST5 (2), spa-t3262/agr-II/ST5 (1), spa-t605/agr-II/ST126 (3), and spa-t878/agr-III/ST2849 (1). S. aureus ST398 strain was methicillin-resistant and showed a multidrug resistance phenotype. Virulence genes tst, etd, sea, sec, seg, sei, sem, sen, seo, and seu, were detected among S. aureus and only ST5 strains showed genes of immune evasion cluster. Thirty-two coagulase-negative Staphylococcus of 12 different species were recovered (number of strains): Staphylococcus equorum (7), Staphylococcus vitulinus (4), Staphylococcus lentus (4), Staphylococcus sciuri (4), Staphylococcus fleurettii (2), Staphylococcus haemolyticus (2), Staphylococcus hominis (2), Staphylococcus saprophyticus (2), Staphylococcus succinus (2), Staphylococcus capitis (1), Staphylococcus cohnii (1), and Staphylococcus epidermidis (1). Five presented a multidrug resistance phenotype. The following resistance and virulence genes were found: mecA, lnu(A), vga(A), tet(K), erm(C), msr(A)/(B), mph(C), tst, and sem. We found that

Heifers infected with coagulase-negative staphylococci in early lactation have fewer cases of clinical mastitis and higher milk production in their first lactation than noninfected heifers.

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Piepers, S; Opsomer, G; Barkema, H W; de Kruif, A; De Vliegher, S

2010-05-01

Intramammary infections (IMI) in recently calved dairy heifers are more common than was formerly believed but their relevance for future performance has been studied only rarely. In the present study, the association between the IMI status of fresh heifers and their subsequent udder health, milk production, and culling in first lactation was explored. Quarter milk samples were collected between 1 and 4 d in milk (DIM) and between 5 and 8 DIM from 191 dairy heifers in 20 dairy herds for bacteriological culturing and somatic cell count (SCC) analysis. Monthly milk recording data including composite milk SCC and test-day milk yield (MY) were obtained for the first 285 DIM or until culling. Farmer-recorded clinical mastitis cases were available. Data were analyzed using mixed models and survival analysis. Approximately 80% of the fresh heifers (79.8%) had at least one culture-positive quarter. Coagulase-negative staphylococci (CNS) were the most frequently isolated pathogens (72%), followed by esculin-positive streptococci (4.6%) and Staphylococcus aureus (3.5%). Overall geometric mean SCC at quarter level decreased between the first and second samplings from 348,000 to 116,000 cells/mL. Heifers infected with CNS had an intermediate average test-day SCC (84,000 cells/mL) during the first 285 DIM compared with noninfected heifers (53,000 cells/mL) and heifers infected with major pathogens (195,000 cells/mL). Heifers infected with major pathogens had a much lower average daily MY (18.3kg) during first lactation compared with noninfected animals (21.3kg). That CNS-infected heifers out-produced their noninfected counterparts could be at least partially explained by their significantly lower incidence of clinical mastitis (incidence risk 3.6 vs. 21.0%) during first lactation compared with noninfected heifers. We conclude that although CNS cause the majority of IMI in heifers around calving, they should not be a reason for serious concern. Copyright 2010 American Dairy

Comparison of four methods for rapid identification of Staphylococcus aureus directly from BACTEC 9240 blood culture system

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N S Ozen

2011-01-01

Full Text Available Purpose: Differentiation of Staphylococcus aureus (S. aureus from coagulase-negative staphylococci is very important in blood stream infections. Identification of S. aureus and coagulase-negative staphylococci (CoNS from blood cultures takes generally 18-24 h after positive signaling on continuously monitored automated blood culture system. In this study, we evaluated the performance of tube coagulase test (TCT, slide agglutination test (Dry Spot Staphytect Plus, conventional polymerase chain reaction (PCR and LightCycler Staphylococcus MGrade kit directly from blood culture bottles to achieve rapid identification of S. aureus by using the BACTEC 9240 blood culture system. Materials and Methods: A total of 129 BACTEC 9240 bottles growing gram-positive cocci suggesting Staphylococci were tested directly from blood culture broths (BCBs with TCT, Dry Spot Staphytect Plus, conventional PCR and LightCycler Staphylococcus MGrade kit for rapid identification of S. aureus. Results: The sensitivities of the tests were 99, 68, 99 and 100%, respectively. Conclusion: Our results suggested that 2 h TCT was found to be simple and inexpensive method for the rapid identification of S. aureus directly from positive blood cultures.

Perfil de contaminação por Staphylococcus e suas enterotoxinas e monitorização das condições de higiene em uma linha de produção de queijo de coalho Contamination profile for staphylococci and its enterotoxins and monitorization of the conditions of hygiene in a ‘coalho' cheese production line

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Maria de Fatima Borges

2008-08-01

Full Text Available Avaliou-se o perfil de contaminação por Staphylococcus e suas enterotoxinas e monitorou-se as condições de higiene em uma linha de produção de queijo de coalho por meio da técnica de bioluminescência (ATP. A população de Staphylococcus sp. variou de This research aimed to evaluate the contamination by staphylococci and its enterotoxins as well as to monitor the conditions of hygiene from a coalho cheese production line, using ATP bioluminescence assay. Staphylococcus sp. population varied from <1CFU mL-1, in pasteurized milk to 1.5 x 107CFU mL-1, in raw milk, whereas coagulase-positive staphylococci count ranged from <1CFU mL-1, in pasteurized milk to 5.0 x 106CFU mL-1 in raw milk. Coagulase-positive staphylococci were detected in 100% (25/25 of the raw milk samples and in 8% (2/25 of cheese samples. Twelve Staphylococcus species were identified within the selected 68 isolates, being nine negative and three positive for coagulase. Raw milk samples showed a high rate of coagulase-positive, being S. aureus the most common, whereas other product samples and equipment surfaces, pieces of furniture, utensils and manipulator gloves samples presented a high frequency of coagulase-negative and low frequency of coagulase-positive. Staphylococcal enterotoxin was detected in 20% of the raw milk samples and therefore in pasteurized milk, curd and cheese. ATP measurement permitted to assess the effectiveness of the surfaces cleaning, being considered adequate in 62.1% (36/95, "alert state" in 23.2% (22/95 and inadequate in 14.7% (14/95 of surfaces evaluated. Detection of staphylococci species with enterotoxigenic potential as well as enterotoxin presence reveal dissemination of contamination at the "coalho" cheese production line, possibly due inappropriate Good Manufacturing Practices (GMP from the initial milking step until the final cheese production.

Incidence, adherence, and antibiotic resistance of coagulase-negative Staphylococcus species causing human disease.

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Needham, C A; Stempsey, W

1984-09-01

Fifty-two isolates of coagulase-negative Staphylococcus species recovered from the blood or intravenous catheters of patients with clinically significant disease were compared to 60 similar isolates from patients who were presumably colonized. All isolates were identified and evaluated for ability to adhere to smooth surfaces, and resistance to anti-staphylococcal penicillins. S. epidermidis, S. hominis, and S. haemolyticus were the most frequently occurring species, representing 65%, 15%, and 10%, respectively, of disease isolates and 57%, 25%, and 8% of colonizers. The seven other species recovered accounted for only 10% of the total in both groups. Differences in isolation rates of each species within the two groups were not significant and were reflective of their reported incidence in the normal flora. All species of coagulase-negative Staphylococcus (except S. capitis and S. cohnii, which were isolated in very small numbers) were capable of adhering to smooth surfaces. S. hominis disease isolates were all capable of adherence, and the difference between the disease isolates and colonizers was statistically significant (p less than 0.02). This was not true for any other species that was analyzed nor for all isolates considered as a whole. Resistance to anti-staphylococcal penicillins was documented for all coagulase-negative Staphylococcus species, and was more frequent in S. epidermidis disease isolates than colonizers (p less than 0.05). No correlation was found between resistance to antistaphylococcal penicillins and ability to adhere.

An investigation of resistance to β-lactam antimicrobials among staphylococci isolated from pigs with exudative epidermitis.

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Park, Jeonghwa; Friendship, Robert M; Weese, J Scott; Poljak, Zvonimir; Dewey, Cate E

2013-10-17

. While this has been reported for acquisition of methicillin-resistance from coagulase negative staphylococci to S. aureus, these data suggest that transmission to or from the porcine pathogen S. hyicus may also occur. The identification of methicillin resistance in a variety of staphylococcal species in pigs does raise concerns about the spread of serious multi-drug resistance in food producing animals and warrants further study.

Biofilm Formation and Antimicrobial Susceptibility of Staphylococcus epidermidis Strains from a Hospital Environment

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Robert D. Wojtyczka

2014-04-01

Full Text Available The hospital environment microflora comprise a wide variety of microorganisms which are more or less pathogenic and where staphylococci are one of the most common types. The aim of the presented study was to evaluate the prevalence of the biofilm forming coagulase-negative staphylococci (CoNS in a hospital environment as a risk factor for nosocomial infections. Among 122 isolated and tested strains of CoNS the most frequent were: S. epidermidis—32 strains, S. haemolyticus—31 strains, S. capitis subsp. capitis— 21 strains, S. hominis—11 strains, S. cohnii subsp. cohnii—nine strains. In case of CoNS, the main molecule responsible for intercellular adhesion is a polysaccharide intercellular adhesin (PIA, encoded on the ica gene operon. The analysis revealed the presence of the icaADBC operon genes in 46.88% of S. epidermidis isolates. IcaA and icaD were present in 34.38% and 28.13% of strains respectively while IcaC gene was present in 37.50% of strains. IcaB gene was found in 21.88% of S. epidermidis strains. In 15 (63% strains all icaADBC operon genes were observed. The assessment of antibacterial drugs susceptibility demonstrated that analyzed CoNS strains were highly resistant to macrolides and lincosamides and more sensitive to rifampicin and linezolid. Our data indicates that the hospital environment can be colonized by biofilm forming coagulase-negative staphylococci and transmission of these strains can cause an increased risk of serious nosocomial infections.

Biofilm formation and antimicrobial susceptibility of Staphylococcus epidermidis strains from a hospital environment.

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Wojtyczka, Robert D; Orlewska, Kamila; Kępa, Małgorzata; Idzik, Danuta; Dziedzic, Arkadiusz; Mularz, Tomasz; Krawczyk, Michał; Miklasińska, Maria; Wąsik, Tomasz J

2014-04-25

The hospital environment microflora comprise a wide variety of microorganisms which are more or less pathogenic and where staphylococci are one of the most common types. The aim of the presented study was to evaluate the prevalence of the biofilm forming coagulase-negative staphylococci (CoNS) in a hospital environment as a risk factor for nosocomial infections. Among 122 isolated and tested strains of CoNS the most frequent were: S. epidermidis-32 strains, S. haemolyticus-31 strains, S. capitis subsp. capitis- 21 strains, S. hominis-11 strains, S. cohnii subsp. cohnii-nine strains. In case of CoNS, the main molecule responsible for intercellular adhesion is a polysaccharide intercellular adhesin (PIA), encoded on the ica gene operon. The analysis revealed the presence of the icaADBC operon genes in 46.88% of S. epidermidis isolates. IcaA and icaD were present in 34.38% and 28.13% of strains respectively while IcaC gene was present in 37.50% of strains. IcaB gene was found in 21.88% of S. epidermidis strains. In 15 (63%) strains all icaADBC operon genes were observed. The assessment of antibacterial drugs susceptibility demonstrated that analyzed CoNS strains were highly resistant to macrolides and lincosamides and more sensitive to rifampicin and linezolid. Our data indicates that the hospital environment can be colonized by biofilm forming coagulase-negative staphylococci and transmission of these strains can cause an increased risk of serious nosocomial infections.

Antimicrobial resistance levels amongst staphylococci isolated from clinical cases of bovine mastitis in Kosovo.

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Mehmeti, Ibrahim; Behluli, Behlul; Mestani, Mergim; Ademi, Arsim; Nes, Ingolf F; Diep, Dzung B

2016-10-31

Mastitis is one of the most frequent and costly disease in cattle. We studied milk samples from cattle with mastitis from farms in Kosovo to identify mastitis-causing pathogens and possible effective antibiotics. Our ultimate goal is to help implement adequate antibiotic management and treatment practices in Kosovo METHODOLOGY: A total of 152 milk samples were collected from cows with clinical mastitis from different farms in Kosovo. After identification of microorganisms, antibiotic susceptibility and the occurrence of enterotoxins was investigated. Staphylococci were found in 89 samples, of which 58 were coagulase negative and 31 coagulase positive. S. aureus was isolated from 27 samples, S. epidermidis from 25, and S. chromogenes from 15, while other species of staphylococci were isolated from the remaining 22 isolates. Interestingly, the bacterial diversity was different between cows in different periods of lactation and among different breeds. Most of the isolates (76/89) were resistant to two or more antibiotics. The highest resistance was to penicillin and ampicillin (> 65%), followed by tetracycline, oxacillin, streptomycin, chloramphenicol (> 23%), and less than 3% to erythromycin. Of the 89 isolates, 40 produced enterotoxins that were most frequently typed as A and C. We detected human bacterial pathogens in the cultures of milk samples from cows with mastitis. The isolates demonstrated resistance to two or more antibiotics, some of which are frequently used to treat animal and human infections. We recommend increased control and more stringent use of antibiotics in veterinary as well as human medicine.

Evaluation of the LightCycler Staphylococcus M GRADE kits on positive blood cultures that contained gram-positive cocci in clusters.

Science.gov (United States)

Shrestha, Nabin K; Tuohy, Marion J; Padmanabhan, Ravindran A; Hall, Gerri S; Procop, Gary W

2005-12-01

We evaluated the Roche LightCycler Staphylococcus M(GRADE) kits to differentiate between Staphylococcus aureus and coagulase-negative staphylococci in blood cultures growing clusters of gram-positive cocci. Testing 100 bottles (36 containing S. aureus), the assay was 100% sensitive and 98.44% specific for S. aureus and 100% sensitive and specific for coagulase-negative staphylococci.

Ocurrence of Vibrio spp., positive coagulase staphylococci and enteric bacteria in oysters (Crassostrea gigas harvested in the south bay of Santa Catarina island, Brazil Ocorrência de Vibrio spp., estafilococos coagulase positivo e bactérias entéricas em ostras (Crassostrea gigas cultivadas na baía sul da ilha de Santa Catarina, Brasil

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Roberta Juliano Ramos

2012-09-01

Full Text Available The aim of this study was to assess the contamination of oysters (Crassostrea gigas, harvested in six different regions of the South Bay of Santa Catarina Island, with Coliforms at 45 ºC, Escherichia coli, Vibrio spp., positive coagulase staphylococci, and Salmonella sp. over a period of one year. One hundred eighty oyster samples were collected directly from their culture sites and analyzed. Each sample consisted of a pool of 12 oysters. All of the samples analyzed showed absence of Salmonella, 18 (10% samples showed presence of Escherichia coli, 15 (8.3% samples were positive for V. alginolyticus, and Vibriocholerae was detected in 4 samples (2.2%. The counts of positive-coagulase staphylococci varied from O objetivo deste estudo foi avaliar a contaminação de ostras (Crassostrea gigas cultivadas em diferentes regiões da Baía Sul da Ilha de Santa Catarina, por coliformes a 45 ºC, Escherichia coli, Vibrio spp. Estafilococos coagulase positiva e Salmonella sp., durante o período de um ano. Foram analisadas 180 amostras, coletadas diretamente no local de cultivo. Todas as amostras analisadas apresentaram ausência de Salmonella, 18 (10% amostras apresentaram presença de Escherichia coli, 15 (8,3% amostras positivas para Vibrio alginolyticus e V. cholerae foi detectado em 4 amostras (2,2%. As contagens de Estafilococos coagulase positiva variaram de <10 a 1,9 x 102 UFC.g-1, enquanto que as contagens de coliformes a 45 ºC e E. coli variaram de <3 a 1,5 x 102 NMP.g-1 e <3 e 4,3 x 10 NMP.g-1, respectivamente. As contagens de V. parahaemolyticus e V. vulnificus variaram de <3 a 7 NMP.g-1, para ambos os microrganismos, sugerindo um monitoramento tanto destas espécies quanto da temperatura das águas marinhas nas regiões de cultivo. Com base nos resultados das análises microbiológicas, as amostras analisadas mostraram qualidade bacteriológica aceitável, ou seja, dentro dos parâmetros estabelecidos na legislação brasileira.

Prevalence and risk factors for carriage of multi-drug resistant Staphylococci in healthy cats and dogs

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Regula, Gertraud; Petrini, Orlando; Zinsstag, Jakob; Schelling, Esther

2013-01-01

We investigated the distribution of commensal staphylococcal species and determined the prevalence of multi-drug resistance in healthy cats and dogs. Risk factors associated with the carriage of multi-drug resistant strains were explored. Isolates from 256 dogs and 277 cats were identified at the species level using matrix-assisted laser desorption ionisation-time of flight mass spectrometry. The diversity of coagulase-negative Staphylococci (CNS) was high, with 22 species in dogs and 24 in cats. Multi-drug resistance was frequent (17%) and not always associated with the presence of the mecA gene. A stay in a veterinary clinic in the last year was associated with an increased risk of colonisation by multi-drug resistant Staphylococci (OR = 2.4, 95% CI: 1.1~5.2, p value LRT = 0.04). When identifying efficient control strategies against antibiotic resistance, the presence of mechanisms other than methicillin resistance and the possible role of CNS in the spread of resistance determinants should be considered. PMID:23820161

Intra-species diversity and epidemiology varies among coagulase-negative Staphylococcus species causing bovine intramammary infections.

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Piessens, V; De Vliegher, S; Verbist, B; Braem, G; Van Nuffel, A; De Vuyst, L; Heyndrickx, M; Van Coillie, E

2012-02-24

Although many studies report coagulase-negative staphylococci (CNS) as the predominant cause of subclinical bovine mastitis, their epidemiology is poorly understood. In the current study, the genetic diversity within four CNS species frequently associated with bovine intramammary infections, Staphylococcus haemolyticus, S. simulans, S. chromogenes, and S. epidermidis, was determined. For epidemiological purposes, CNS genotypes recovered from bovine milk collected on six Flemish dairy farms were compared with those from the farm environment, and their distribution within the farms was investigated. Genetic diversity was assessed by two molecular typing techniques, amplification fragment length polymorphism (AFLP) and random amplification of polymorphic DNA (RAPD) analysis. Subtyping revealed the highest genetic heterogeneity among S. haemolyticus isolates. A large variety of genotypes was found among environmental isolates, of which several could be linked with intramammary infection, indicating that the environment could act as a potential source for infection. For S. simulans, various genotypes were found in the environment, but a link with IMI was less obvious. For S. epidermidis and S. chromogenes, genetic heterogeneity was limited and the sporadic isolates from environment displayed largely the same genotypes as those from milk. The higher clonality of the S. epidermidis and S. chromogenes isolates from milk suggests that specific genotypes probably disseminate within herds and are more udder-adapted. Environmental sources and cow-to-cow transmission both seem to be involved in the epidemiology of CNS, although their relative importance might substantially vary between species. Copyright © 2011 Elsevier B.V. All rights reserved.

Molecular Detection of Inducible Clindamycin Resistance among Staphylococcal Strains Isolated from Hospital Patients

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Shadiyeh Abdollahi

2013-04-01

Full Text Available Background & Objectives: Macrolide, lincosamide and streptogramin B (MLSB antimicrobial agents are used in the treatment of staphylococcal infections. They prevent the microbial protein synthesis system through binding to 23 S rRNA. The aim of this study was to apply molecular methods to detect inducible clindamycin resistance genes among staphylococcal strains isolated from clinical specimens.   Methods : Two hundred staphylococcus strains were isolated from nose and throat swabs of patients in Toohid and Besat hospitals in Sanandaj . Antimicrobial susceptibilities of isolates were determined using disc diffusion method, agar screen test and D-Test. A multiplex PCR was performed using primers specific for erm (A, B, C, TR genes.   Results: Out of 200 isolates, 18.5 % were MRSA and 32% were MRCNS (methicillin resistant coagulase negative staphylococci. Of 80 erythromycin resistant isolates, 48 were coagulase negative and 32 were S. aureus. Among the 48 coagulase negative staphylococci (CONS isolates, 11.63% expressed the MLSB-inducible phenotypes. Using PCR, the frequency of different genes in the collection of isolates were as follows: ermA 5.41 % , erm B 5.41 % , and erm C 3.13%. The ermTR gene was negative in all isolates. Among the 32 S. aureus isolates, 9.38% expressed the MLSB-nducible phenotype. Using PCR, these isolates harbored erm A (2.22%, ermB (2.22%, ermC (2.22% and ermTR (2.22% .   Conclusion: This is the first study to show the rate of inducible clindamycin clinical isolates of staphylococci harboring erm genes in Sananadaj. It also demonstrated the frequency of erm genes was higher among CONS isolates than S. aureus. This data suggested the transfer of resistance gene from nonpathogenic to pathogenic strains is likely to happen. Therefore, screening and control of these resistance genes is recommended at clinical laboratories.

Commensal coagulase-negative Staphylococcus from the udder of healthy cows inhibits biofilm formation of mastitis-related pathogens.

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Isaac, Paula; Bohl, Luciana Paola; Breser, María Laura; Orellano, María Soledad; Conesa, Agustín; Ferrero, Marcela Alejandra; Porporatto, Carina

2017-08-01

Bovine mastitis, considered the most important cause of economic losses in the dairy industry, is a major concern in veterinary medicine. Staphylococcus aureus and coagulase-negative staphylococci (CNS) are the main pathogens associated with intramammary infections, and bacterial biofilms are suspected to be responsible for the persistence of this disease. CNS from the udder are not necessarily associated with intramammary infections. In fact, some commensal CNS have been shown to have biological activities. This issue led us to screen exoproducts from commensal Staphylococcus chromogenes for anti-biofilm activity against different mastitis pathogens. The cell-free supernatant from S. chromogenes LN1 (LN1-CFS) was confirmed to display a non-biocidal inhibition of pathogenic biofilms. The supernatant was subjected to various treatments to estimate the nature of the biofilm-inhibiting compounds. The results showed that the bioactive compound >5KDa in mass is sensitive to thermal treatment and proteinase K digestion, suggesting its protein properties. LN1-CFS was able to significantly inhibit S. aureus and CNS biofilm formation in a dose-independent manner and without affecting the viability of bovine cells. These findings reveal a new activity of the udder microflora of healthy animals. Studies are underway to purify and identify the anti-biofilm biocompound and to evaluate its biological activity in vivo. Copyright © 2017 Elsevier B.V. All rights reserved.

Prevalence of Methicillin Resistant Staphylococcus aureus in Clinical Samples of Teerthankar Mahaveer Medical College Hospital and Research Centre (TMMCH & RC, Moradabad (UP, India

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Bina Pani Gupta

2017-06-01

Full Text Available Staphylococcus aureus is the emerging and prevalent pathogen causing serious infections in community and hospital associated diseases. S. aureus resistant to methicillin is nowadays a big and expanding problem of concern in India. Amongst the different pathogens, S. aureus is being studied for prevalence of infections and drug resistance behavior. The present study describes the dominance of Staphylococcus aureus prevalence in the clinical samples of TMU, Moradabad, India. The study showed the isolation of 450 cultures of S. aureus from different samples. Amongst which, 234 isolates of S. aureus were from pus, 164 isolates were from blood, 15 isolates were from respiratory fluid samples, 33 isolates were from urine samples and 04 isolates were from ear swabs and nasal swabs. These strains of S. aureus were screened for characteristic coagulase assay. The strains were found to be coagulase positive and coagulases negative both. It was observed that, amongst, 450 isolates of Staphylococci, 185 (41.11% strains were coagulase positive and 265 (58.88% were coagulase negative. A total of 142 (76.75% of the coagulase positive staphylococci strains shows resistance to methicillin and 202 (76.22% coagulase negative strains showed methicillin resistance. Methicillin resistance was consistent when tested with other antibiotics in coagulase positive strains but when studied about coagulase negative strains, about 12.5% strains showed sensitivity with other antibiotics although they were found resistant when checked with methicillin. It was determined that, on an average, 85 (18.88% Staphylococci strains were resistant.

Etiology of canine otitis media and antimicrobial susceptibility of coagulase-positive Staphylococci in Fortaleza city, Brazil Etiologia da otite média canina e susceptibilidade a antimicrobianos de Staphylococcus coagulase-positiva em Fortaleza, Brasil

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Lis Christina de Oliveira

2006-06-01

Full Text Available This study evaluated the middle ear microbiota and antimicrobial susceptibility patterns from strains isolated from dogs with otitis media. A total of 62 dogs obtained from Zoonoses Control Center of Fortaleza City Ceará State / Brazil were studied over a 10-month period (August/2003 to June/2004. Of the total, 46.8% (n=30 of the animals were positive for otitis media and the infection was monomicrobial in 76.6% of them. The most frequent isolated agents were coagulase-positive Staphylococci (CPS-55% and Pseudomonas sp (10%. For S. intermedius (n=13 and S. aureus subsp aureus (n=9, respectively, the greater resistance rates were observed using penicillin G (30.76% and 44.44%, ampicillin (7.69% and 44.44%, erythromycin (23.07% and 44.44%, clindamycin (23.07% and 44.44% and thrimethropim/sulfamethoxazol (15.38% and 33.33%.O presente trabalho avaliou a microbiota do ouvido médio e os perfis de susceptibilidade a antimicrobianos de cepas isoladas de cães com otite média. Um total de 62 cães obtidos no Centro de Controle de Zoonoses de Fortaleza Ceará / Brasil foram estudados no período de 10 meses (agosto/2003 a junho/2004. Do total de animais, 46.8% (n=30 foram positivos para otite media e a infecção envolvida era monomicrobiana em 76,6% dos casos. Os agentes isolados com maior frequência foram Staphylococcus coagulase-positiva (CPS-55% e Pseudomonas sp (10%. Considerando-se S. intermedius (n=13 e S. aureus subsp aureus (n=9, respectivamente, as mais elevadas taxas resistência foram observadas frente a: penicilina G (30,76% e 44,44%, ampicilina (7,69% e 44,44%, eritromicina (23,07% e 44,44%, clindamicina (23,07% e 44,44% e trimetropim/sulfametoxazol (15,38% e 33,33%.

Comparação entre o sistema Petrifilm RSA® e a metodologia convencional para a enumeração de estafilococos coagulase positiva em alimentos Comparison of Petrifilm RSA system with the traditional methodology for the enumeration of coagulase-positive Staphylococcus in foods

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Anderson de Souza Sant'ana

2005-09-01

Full Text Available A pesquisa de estafilococos coagulase positiva em alimentos é feita através de sua detecção e enumeração em meios seletivos e diferenciais e posterior caracterização pelos testes de coagulase, termonuclease, Gram e catalase. Estes testes podem requerer até quatro dias para obtenção dos resultados finais, além do tempo e material dispensados ao seu uso. As placas Petrfilm® RSA são uma alternativa a esta metodologia. No presente estudo, foram analisadas 62 amostras de diferentes alimentos comparando-se a metodologia tradicional (ABP, seguido dos testes de coagulaseou Staphytect Plus e o sistema Petrifilm. O sistema Petrifilm® RSA diferiu significativamente da metodologia tradicional, dando médias de contagem superiores. Ao se considerar colônias típicas e atípicas, o ABP seguido de confirmação pelo Staphytect Plus diferiu significativamente dos demais métodos testados. O Petrifilm RSA é uma alternativa para a enumeração de estafilococos coagulase positivos em alimentos, em virtude do menor tempo (aproximadamente 31 horas, para obter-se resultados realmente quantitativos. Deve-se testar tanto colônias típicas quanto atípicas crescidas no ABP, para se evitar falhas na quantificação dos resultados. Esta contagem é mais significativa ao se usar o teste de aglutinação em látex (Staphytect Plus. A análise de estafilococos em alimentos apresenta diversas limitações.Foods are examined for the presence of coagulase-positive staphylococci using selective and differential media followed by characterization for coagulase, thermoestable nuclease, Gram and catalase tests. These tests may require up to four days to obtain the results, besides time and material used. The Petrifilm® rapid S.aureus count plate is a alternative to traditional methodology. In this study, 62 samples of several foods were analysed comparing the BPA method followed by coagulase or latex agglutination tests and Petrifilm® RSA method. The Petrifilm

Microbiological quality of goat milk on rural properties in the region of Macaíba/RN

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Joyce Bruna Paiva Silva

2018-02-01

Full Text Available Goat’s milk is an excellent food that can guarantee beneficial effects to human health, but its characteristics are easily altered by the action of microorganisms and by manipulation. The present study aimed to evaluate the microbiological quality of goat milk in 11 farms in the region of Macaíba/RN. Samples of milk and swabs from the hands of milkers, utensils and goat teats were collected and transported in a thermal box (10 ºC – 12 ºC to the Laboratory of Food Engineering of UFRN. The microorganisms studied were the aerobic mesophilic bacteria, psychrotrophic, coagulase positive and negative staphylococci, coliforms at 35 ºC and 45 ºC. Regarding the hands of milkers, 56% presented contamination by aerobic mesophilic bacteria. In the analyzed utensils were found, in 18.2%, coliforms at 45 ºC and coagulase positive staphylococci, as well as coagulase negative staphylococci (63.6% and coliforms at 35 ºC in 27.3% of the samples. For cold raw goat milk, 10% of the samples presented contamination with psychrotrophic and 17% with coliforms at 45 ºC. Regarding goat teats, 52% of the samples had aerobic mesophilic bacteria counts above 103 CFU/ceiling, 61% presented coagulase negative staphylococci and 10% coagulase positive staphylococci, this one of the main agents causing mastitis. Thus, these values indicate that hygienic procedures need to be adopted appropriately in the milking of raw goat milk, requiring guidelines that enable producers to obtain higher quality milk.

Diversity and evolution of blaZ from Staphylococcus aureus and coagulase-negative staphylococci

DEFF Research Database (Denmark)

Olsen, John E.; Christensen, Henrik; Aarestrup, Frank Møller

2006-01-01

and sequences retrieved from public databases were compared. A phylogenetic tree showed that blaZ exists in three evolutionary lines: one group was of plasmid origin, one group was of chromosomal origin and one intermediate group. Sixty-nine sequence types were demonstrated. They translated into 11 BlaZ protein...... types. The major types all contained strains of both human and bovine origin, and more than one Staphylococcus species, demonstrating a shared gene pool. In a comparison of S. aureus and CoNS obtained from five Danish cattle herds, the same type of blaZ was only detected in one case. Conclusions...

Prevalence of methicillin-resistant staphylococci isolated from different biological samples at Policlinico Umberto I of Rome: correlation with vancomycin susceptibility

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Maria Teresa Mascellino

2011-03-01

Full Text Available The methicillin-resistance is increasing all over the world in the last decade. It is more frequent among coagulase-negative staphylococci (MRCoNS; infact the 52% of S. epidermidis strains results to be resistant to methicillin.The methicillin-resistant strains also show a reduced sensitivity towards the first-line agents such as glycopeptides and other antibiotics commonly used in therapy such as trimethoprim-sulphamethoxazole, imipenem, gentamycin, fosfomycin and chlarytromicin. Unlike MRSA (Methicillin-resistant S. aureus, MRCoNS resistance to glycopeptides generally concerns teicoplanin. Although vancomycin resistance is rare in Staphylococcus isolates, the detected shift towards higher values of MICs might affect patient’s clinical outcome.

Characterization of staphylococci in urban wastewater treatment plants in Spain, with detection of methicillin resistant Staphylococcus aureus ST398.

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Gómez, Paula; Lozano, Carmen; Benito, Daniel; Estepa, Vanesa; Tenorio, Carmen; Zarazaga, Myriam; Torres, Carmen

2016-05-01

The objective of this study was to determine the prevalence of Staphylococcus in urban wastewater treatment plants (UWTP) of La Rioja (Spain), and to characterize de obtained isolates. 16 wastewater samples (8 influent, 8 effluent) of six UWTPs were seeded on mannitol-salt-agar and oxacillin-resistance-screening-agar-base for staphylococci and methicillin-resistant Staphylococcus aureus recovery. Antimicrobial susceptibility profile was determined for 16 antibiotics and the presence of 35 antimicrobial resistance genes and 14 virulence genes by PCR. S. aureus was typed by spa, agr, and multilocus-sequence-typing, and the presence of immune-evasion-genes cluster was analyzed. Staphylococcus spp. were detected in 13 of 16 tested wastewater samples (81%), although the number of CFU/mL decreased after treatment. 40 staphylococci were recovered (1-5/sample), and 8 of them were identified as S. aureus being typed as (number of strains): spa-t011/agr-II/ST398 (1), spa-t002/agr-II/ST5 (2), spa-t3262/agr-II/ST5 (1), spa-t605/agr-II/ST126 (3), and spa-t878/agr-III/ST2849 (1). S. aureus ST398 strain was methicillin-resistant and showed a multidrug resistance phenotype. Virulence genes tst, etd, sea, sec, seg, sei, sem, sen, seo, and seu, were detected among S. aureus and only ST5 strains showed genes of immune evasion cluster. Thirty-two coagulase-negative Staphylococcus of 12 different species were recovered (number of strains): Staphylococcus equorum (7), Staphylococcus vitulinus (4), Staphylococcus lentus (4), Staphylococcus sciuri (4), Staphylococcus fleurettii (2), Staphylococcus haemolyticus (2), Staphylococcus hominis (2), Staphylococcus saprophyticus (2), Staphylococcus succinus (2), Staphylococcus capitis (1), Staphylococcus cohnii (1), and Staphylococcus epidermidis (1). Five presented a multidrug resistance phenotype. The following resistance and virulence genes were found: mecA, lnu(A), vga(A), tet(K), erm(C), msr(A)/(B), mph(C), tst, and sem. We found that

[Influence of testing conditions on the susceptibility results of Staphylococcus cohnii to beta-lactams].

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Nowak, Tonmasz; Szewczyk, Eligia M

2006-01-01

The high occurence of coagulase-negative staphylococci among bacteria responsible for hospital infections is unquestioned. Studies on the poorly-known novobiocin-resistant, coagulase-negative Staphylococcus cohnii were undertaken. The possibilities of optimizing conditions for determination of susceptibility to beta-lactam antibiotics of this species were researched. In the case of S. cohnii the new cefoxitin test for detection of methicillin resistant strains, introduced by the National Reference Centre for Antibiotics in Poland was found as a good and of credible quality. It was also shown, that application in in vitro examination conditions stimulating the mechanisms of resistance to beta-lactam antibiotics, supplies credible results relating to their true susceptibility. The necessity of establishing individual conditions for susceptibility determination in different species of coagulase-negative staphylococci was suggested.

Acute Peritonitis Caused by Staphylococcus capitis in a Peritoneal Dialysis Patient.

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Basic-Jukic, Nikolina

Acute peritonitis remains the most common complication of peritoneal dialysis (PD), with coagulase-negative staphylococci (CoNS) reported to account for more than 25% of peritonitis episodes (1). Staphylococcus capitis is a gram-positive, catalase-positive CoNS that was originally identified as a commensal on the skin of the human scalp (2). Advancement of microbiological technologies for bacterial identification enables diagnosis of previously unknown causes of acute peritonitis. This is the first reported case of acute peritonitis in a PD patient caused by S. capitis. Copyright © 2017 International Society for Peritoneal Dialysis.

Increasing trend of community-acquired methicillin-resistant: Staphylococcal carriers: An alarming bell for urgent measures

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Poongodi Lakshmi Santhana Kumarasamy

2015-01-01

Full Text Available Background: An increase in the incidence of infections caused by community-associated-methicillin resistant Staphylococcus aureus (MRSA has been reported. Hence, the knowledge of resistance pattern of these isolates is a precondition for alleviating emerging antibiotic resistance and devising better treatment strategies Aim: To find out the prevalence of community-acquired methicillin-resistant staphylococcal strains from nasal carriers. Materials and Methods: A total of 352 nasal swabs collected during routine health checkup were analyzed. Results: Of the 58 (16% staphylococci isolated, 32 (55% were S. aureus and 26 (45% were coagulase-negative staphylococci (CoNS. Methicillin resistance was observed in 7 (22% of staphylococci aureus and 11 (42% of CoNS. "D test" was positive in 1 (14% MRSA, 2 (8% methicillin-susceptible S. aureus and 2 (8% methicillin resistant-CoNS. Conclusion: Effective implementation of the antibiotic policy along with measures like hand wash, isolation of patients will reduce the incidence of resistance.

COAGULASE POSITIVE STAPHYLOCOCCI RESISTANCE TO BETALACTAM ANTIBIOTICS: USING IODOMETRIC AND ACIDOMETRIC ASSAY – 1999

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A TAVAKOLI

2002-12-01

Full Text Available Introduction. It is very important to know the resistant bacteria to common used antibiotics in our community. Staphylococcus coagulase positive was the main cause of infection in infectious disease. This study was done to demonstrate the pattern of resistance to batalactamase antibiotics among staphiococci. Methods. During a period of five month, 38 coagulase positive staphylococcus isolates were identified from various clinical specimens from 600 patients at the AI-Zahra university hospital (affiliated to IUMSHS. Results. Betalactamase production assays using rapid acidometric and iodometric tests showed that 78.9 percent and 73.6 percent of isolates were positive, respectively. The differnce in determination rate between acidometric and iodometric tests was not statistically significant. Moreover the acidometric test was cheaper and more easy to perform than iodometric test. In vitro sensitivity testing using the disc diffusion method showed that all of isolates were resistant to carbenicillin, ampicillin and amoxicillin, while 7.9 percent and 13.2 percent were resistant to cefazolin and cephalexin, respectively. Discussion. We recommend use of cefazolin, cephalexin and oxacillin for treatment of patients with staphylococcus infections.

Antibiotic resistance and enterotoxin genes in Staphylococcus sp. isolates from polluted water in Southern Brazil

OpenAIRE

BASSO, ANA P.; MARTINS, PAULA D.; NACHTIGALL, GISELE; SAND, SUELI VAN DER; MOURA, TIANE M. DE; FRAZZON, ANA PAULA G.

2014-01-01

The aim of this study was to evaluate the species distribution, antibiotic-resistance profile and presence of enterotoxin (SE) genes in staphylococci isolated from the Dilúvio stream in South Brazil. Eighty-eight staphylococci were identified, 93.18% were identified as coagulase-negative (CNS) and 6.82% coagulase-positive (CPS). Fourteen Staphylococcus species were detected and the most frequently were Staphylococcus cohnii (30.48%) and S. haemolyticus (21.95%). Resistance to erythromycin was...

The effectiveness of lysostaphin therapy for experimental coagulase-negative Staphylococcus endophthalmitis.

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McCormick, Clare C; Dajcs, Joseph J; Reed, Julian M; Marquart, Mary E; O'Callaghan, Richard J

2006-03-01

To quantitatively determine the effectiveness of lysostaphin therapy for experimental endophthalmitis mediated by coagulase-negative Staphylococcus species, the leading cause of postsurgical endophthalmitis. Minimal inhibitory concentrations (MIC) of lysostaphin were determined for 54 isolates representing the following species: S. epidermidis, S. warneri, S. haemolyticus, S. cohnii, S. simulans, and S. capitis. The effectiveness of lysostaphin therapy was tested in an experimental model of endophthalmitis by intravitreally injecting log phase bacteria (100 colony-forming units; cfu) into rabbit eyes (n = 3 eyes per group). At 8 hr postinfection (PI), lysostaphin (250 microg) was injected intravitreally, and the number of cfu/ml of vitreous was determined at 24 hr PI. Average MIC for S. epidermidis was 0.7 microg/ml for 90% of the 33 strains tested. Six methicillin-resistant strains of S. epidermidis (MRSE) had an average MIC of 0.74 micro g/ml. All other species had MIC values of =1.1 microg/ml, except for one strain of S. capitis (MIC = 15.6 microg/ml) and one S. haemolyticus (MIC = 1.41 microg/ml). At 24 hr PI, all untreated eyes had between 5.7 and 8.08 log cfu/ml vitreous humor. Treatment with lysostaphin significantly reduced the cfu/ml as compared with untreated eyes for 13 strains tested in vivo (p = 0.020), but not for two S. haemolyticus strains (p = 0.13), two MRSE strains (p = 0.544), or one S. cohnii strain (p = 0.1366). Treatment with lysostaphin reduced the cfu/ml of methicillin-sensitive S. epidermidis strains by 6 logs; for S. warneri, there was a 2 log reduction; and for the other species a 4 log reduction in cfu/ml relative to untreated eyes. Lysostaphin was mostly effective in treating coagulase-negative staphylococcal experimental endophthalmitis.

Role of blood culture systems in the evaluation of epidemiological features of coagulase-negative staphylococcal bloodstream infection in critically ill patients.

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Oud, L; Krimerman, S; Salam, N; Srugo, I

1999-12-01

The impact of blood culture systems on the detection of coagulase-negative staphylococcal bloodstream infections in critically ill patients prior to and following the introduction of the Bactec 9240 blood culture system (Becton Dickinson Diagnostic Instrument Systems, USA), which replaced the Bactec NR 730 (Becton Dickinson Diagnostic Instrument Systems), was investigated over a 3-year period. Following the introduction of the new culture system, the incidence of bloodstream infections doubled (P<0.001). Patient demographics, severity of illness, and mortality remained unchanged, while the annual standardized mortality ratio decreased significantly. These data suggest that blood culture systems may have a major impact on the perceived incidence of coagulase-negative staphylococcal bloodstream infections in this population.

Bacterial Aggregates Establish at the Edges of Acute Epidermal Wounds

DEFF Research Database (Denmark)

Bay, Lene; Kragh, Kasper N.; Eickhardt, Steffen R.

2018-01-01

for culturing from the wounds and adjacent skin, and the wounds including adjacent skin were excised. Tissue sections were stained with peptide nucleic acid (PNA) fluorescence in situ hybridization (FISH) probes, counterstained by 4′,6-diamidino-2-phenylindole, and evaluated by confocal laser scanning...... microscopy (CLSM). Results: No bacterial aggregates were detected at day 0. At day 4, coagulase-negative staphylococci (CoNS) were the sole bacteria identified by CLSM/PNA-FISH and culturing. CoNS was isolated from 78% of the wound swabs and 48% of the skin swabs. Bacterial aggregates (5–150 μm) were...

Antimicrobial resistance in coagulase-positive staphylococci isolated from companion animals in Australia: A one year study.

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Saputra, Sugiyono; Jordan, David; Worthing, Kate A; Norris, Jacqueline M; Wong, Hui S; Abraham, Rebecca; Trott, Darren J; Abraham, Sam

2017-01-01

Methicillin-resistant coagulase-positive staphylococci (CoPS) have become increasingly recognised as opportunistic pathogens that limit therapeutic options in companion animals. The frequency of methicillin resistance amongst clinical isolates on an Australia-wide level is unknown. This study determined antimicrobial susceptibility patterns for CoPS isolated from clinical infections in companion animals (dogs, cats and horses) as part of the first nation-wide survey on antimicrobial resistance in animal pathogens in Australia for a one-year period (January 2013 to January 2014). Clinical Staphylococcus spp. isolates (n = 888) obtained from 22 veterinary diagnostic laboratories were identified by MALDI-TOF mass spectrometry and subjected to antimicrobial susceptibility testing for 16 antimicrobials, representing 12 antimicrobial classes. Potential risk factors associated with methicillin resistance in Staphylococcus pseudintermedius isolates from dogs were analysed based on demographic factors and clinical history, including gender, age, previous antimicrobial treatment, chronic and/or recurrent diseases and site of infections. The most commonly identified CoPS were S. pseudintermedius (70.8%; dogs n = 616, cats n = 13) and S. aureus (13.2%, horses n = 53, dogs n = 47 and cats n = 17). Overall, the frequency of methicillin resistance among S. pseudintermedius (MRSP) and S. aureus (MRSA) was 11.8% and 12.8%, respectively. MRSP isolates were strongly associated with resistance to fluoroquinolones (OR 287; 95%CI 91.2-1144.8) and clindamycin (OR 105.2, 95%CI 48.5-231.9). MRSA isolates from dogs and cats were also more likely to be resistant to fluoroquinolones (OR 5.4, 95%CI 0.6-252.1), whereas MRSA from horses were more likely to be resistant to rifampicin. In multivariate analysis, MRSP-positive status was significantly associated with particular infection sites, including surgical (OR 8.8; 95%CI 3.74-20.7), and skin and soft tissue (OR 3.9; 95%CI 1.97-7.51). S

Research on the Phenotypic Characterization of Mrsa Strains Isolated from Animals

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Iulia Maria BUCUR

2017-05-01

Full Text Available Keywords: chromogen, methicillin, MRSA, resistance Introduction: Currently, both in staphylococci isolated from animals with different diseases, as well as in humans, the MRSA strains (Methicillin Resistant S. aureus are monitored, as the methicillin resistance is associated with the resistance to other antibiotic groups. Methicillin resistance is encoded by mec staphylococcal chromosomal cassettes (SCCmec, which are islands of resistance. These strains can be identified by molecular biology tests and tests that reveal several phenotypic characteristics. The research was made in order to characterize and identify phenotypically the MRSA staphylococci strains isolated from animals. Materials and Methods: Researches were made on 240 coagulase positive and coagulase negative strains of staphylococci. Mannitol fermentation was tested on Champan medium, free coagulase was revealed on Baird-Parker medium and to identify S. aureus subsp. aureus was used the chromogenic medium Chromatic Staph. Methicillin-resistant strains were detected by disc diffusion method, using biodiscs with methicillin, oxacillin and cefoxitin. Also, to identify the MRSA strains, was used the chromogenic medium Chromatic MRSA. Results: The isolates were positive to mannitol and produced complete haemolysis or were unhaemolytic. A total of 44 strains produced free coagulase on Baird-Parker medium, considered coagulase positive strains, while 196 were coagulase negative strains. The isolates conducted differently to methicillin: 22,08% of strains were resistant, 51,25% of strains were susceptible and 26,66% had intermediate resistance, while the resistant strains to oxacillin were 42,91%. The increased frequency of methicillin-resistant strains of staphylococci and, particularly, MRSA strains, determined using the cefoxitin disk diffusion test, which is more reliable than methicillin and oxacillin. On the MRSA chromogenic medium, the methicillin-resistant strains of staphylococci

Distribution of coagulase-negative Staphylococcus species from milk and environment of dairy cows differs between herds.

Science.gov (United States)

Piessens, V; Van Coillie, E; Verbist, B; Supré, K; Braem, G; Van Nuffel, A; De Vuyst, L; Heyndrickx, M; De Vliegher, S

2011-06-01

In many parts of the world, coagulase-negative staphylococci (CNS) are the predominant pathogens causing intramammary infections (IMI) in dairy cows. The cows' environment is thought to be a possible source for CNS mastitis and this was investigated in the present paper. A longitudinal field study was carried out in 6 well-managed dairy herds to determine the distribution and epidemiology of various CNS species isolated from milk, causing IMI and living freely in the cows' environment, respectively. In each herd, quarter milk samples from a cohort of 10 lactating cows and environmental samples from stall air, slatted floor, sawdust from cubicles, and sawdust stock were collected monthly (n=13). Isolates from quarter milk samples (n=134) and the environment (n=637) were identified to species level using amplified fragment length polymorphism (AFLP) genotyping. Staphylococcus chromogenes, S. haemolyticus, S. epidermidis, and S. simulans accounted for 81.3% of all CNS milk isolates. Quarters were considered infected with CNS (positive IMI status) only when 2 out of 3 consecutive milk samples yielded the same CNS AFLP type. The species causing IMI were S. chromogenes (n=35 samples with positive IMI status), S. haemolyticus (n=29), S. simulans (n=14), and S. epidermidis (n=6). The observed persistent IMI cases (n=17) had a mean duration of 149.4 d (range 63.0 to 329.8 d). The CNS species predominating in the environment were S. equorum, S. sciuri, S. haemolyticus, and S. fleurettii. Herd-to-herd differences in distribution of CNS species were observed in both milk and the environment, suggesting that herd-level factors are involved in the establishment of particular species in a dairy herd. Primary reservoirs of the species causing IMI varied. Staphylococcus chromogenes and S. epidermidis were rarely found in the environment, indicating that other reservoirs were more important in their epidemiology. For S. haemolyticus and S. simulans, the environment was found as a

Invited review: effect, persistence, and virulence of coagulase-negative Staphylococcus species associated with ruminant udder health.

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Vanderhaeghen, W; Piepers, S; Leroy, F; Van Coillie, E; Haesebrouck, F; De Vliegher, S

2014-09-01

The aim of this review is to assess the effect of coagulase-negative staphylococci (CNS) species on udder health and milk yield in ruminants, and to evaluate the capacity of CNS to cause persistent intramammary infections (IMI). Furthermore, the literature on factors suspected of playing a role in the pathogenicity of IMI-associated CNS, such as biofilm formation and the presence of various putative virulence genes, is discussed. The focus is on the 5 CNS species that have been most frequently identified as causing bovine IMI using reliable molecular identification methods (Staphylococcus chromogenes, Staphylococcus simulans, Staphylococcus haemolyticus, Staphylococcus xylosus, and Staphylococcus epidermidis). Although the effect on somatic cell count and milk production is accepted to be generally limited or nonexistent for CNS as a group, indications are that the typical effects differ between CNS species and perhaps even strains. It has also become clear that many CNS species can cause persistent IMI, contrary to what has long been believed. However, this trait appears to be quite complicated, being partly strain dependent and partly dependent on the host's immunity. Consistent definitions of persistence and more uniform methods for testing this phenomenon will benefit future research. The factors explaining the anticipated differences in pathogenic behavior appear to be more difficult to evaluate. Biofilm formation and the presence of various staphylococcal virulence factors do not seem to (directly) influence the effect of CNS on IMI but the available information is indirect or insufficient to draw consistent conclusions. Future studies on the effect, persistence, and virulence of the different CNS species associated with IMI would benefit from using larger and perhaps even shared strain collections and from adjusting study designs to a common framework, as the large variation currently existing therein is a major problem. Also within-species variation should

Teat apex colonization with coagulase-negative Staphylococcus species before parturition: Distribution and species-specific risk factors.

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De Visscher, A; Piepers, S; Haesebrouck, F; De Vliegher, S

2016-02-01

Coagulase-negative staphylococci (CNS) are the main cause of bovine intramammary infections and are also abundantly present in extramammary habitats such as teat apices. Teat apex colonization (TAC) with CNS has already been explored in lactating dairy cows at the species level, whereas this is not true for dry cows and end-term heifers. Therefore, the aim of this observational study was to describe CNS TAC in nonlactating dairy cows and end-term heifers in Flemish dairy herds and to identify associated risk factors at the herd, cow, and quarter level. All CNS were molecularly identified to the species level using transfer RNA intergenic spacer PCR (tDNA-PCR) and sequencing of the 16S rRNA gene, allowing for species-specific statistical analyses using multivariable, multilevel logistic regression. Staphylococcus devriesei, Staphylococcus chromogenes, Staphylococcus haemolyticus, and Staphylococcus equorum were the most frequently isolated species. Staphylococcus chromogenes was the sole species colonizing teat apices of cows and heifers in all herds, whereas large between-herd differences were observed for the other species. Teat apices of red and white Holstein Friesians, of quarters dried off without an internal teat sealer, and swabbed in months with lower precipitation and higher ambient temperature were significantly more likely to be colonized by S. devriesei. Slightly dirty teat apices and teat apices swabbed in months with lower precipitation had higher odds of being colonized by S. chromogenes, whereas teat apices sampled in months with lower precipitation and higher ambient temperature were more likely to be colonized by S. haemolyticus. Dirty teat apices and teat apices swabbed in months with lower ambient temperature in combination with low precipitation had higher odds of being colonized by S. equorum. Diverse factors explaining CNS TAC, yet mostly related to humidity, ambient temperature, and hygiene, substantiate differences in epidemiological

Nosocomial coagulase-negative staphylococcal infections in bone marrow transplantation recipients with central vein catheter. A 5-year prospective study.

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Engelhard, D; Elishoov, H; Strauss, N; Naparstek, E; Nagler, A; Simhon, A; Raveh, D; Slavin, S; Or, R

1996-02-15

The purpose of this study was to examine coagulase-negative staphylococcal infections in bone marrow transplantation (BMT) patients with central vein catheters by investigating incidence, clinical relevance, risk factors, methicillin resistance, clinical impact of initial empiric antimicrobial therapy without vancomycin, and management of documented catheter-related infections. A 5-year prospective study was conducted with daily evaluation of 242 BMT patients during hospitalization, including clinical assessment and blood culture via the Hickman/Broviac catheter. If fever or infected appearance occurred, peripheral blood cultures or exit site cultures, respectively, were done. Results showed a septicemia incidence of 7.0%, including in 6 patients following colonization, in 1 patient with tunnel infection, in 1 patient with thrombophlebitis, in 1 patient with exit site infection, and in 8 patients with septicemia of unknown origin. Total colonization incidence was 7%, with colonization only in 11 patients who had 16 episodes; incidence of exit site infection was 3.7%. Age > or = 18 years was the only identified risk factor for developing staphylococcal infection (P = 0.03). Despite a methicillin resistance rate of 45% and omission of vancomycin from the routine initial empiric antimicrobial regimen, the clinical course of coagulase-negative staphylococcal infections was relatively benign. A single patient, who experienced marrow rejection, died on day +31 with septicemia and only one patient experienced microbiological failure with recurrent colonization. Bacteria grown in both aerobic and anaerobic bottles were more likely true bacteremia than contaminant (P = 0.03). We conclude that the hazard of coagulase-negative staphylococcal infection does not mandate inclusion of a glycopeptide in the initial empiric antimicrobial regimen in BMT patients, even during febrile neutropenia. Hickman/Broviac-related staphylococcal infections, except for tunnel infection or

Prevalence of antiseptic-resistance genes in staphylococci isolated from orthokeratology lens and spectacle wearers in Hong Kong.

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Shi, Guang-sen; Boost, Maureen; Cho, Pauline

2015-05-01

To compare isolation of staphylococci from periorbital tissues and accessories of orthokeratology (ortho-k) lens and spectacle wearers and investigate prevalence of antiseptic-resistance (QAC) genes. To determine minimum inhibitory concentrations (MIC) of antiseptics and antibiotic susceptibility of isolates. Staphylococci were isolated from eyelids, eyelashes, and conjunctival sacs of 23 ortho-k lens wearers and 20 spectacle wearers. Samples were also collected from ortho-k lenses, lens cases, and spectacle frames. Isolations of Staphylococcus aureus were compared between ortho-k subjects and controls for all samples and for coagulase-negative staphylococci (CNS) from conjunctival sacs. QAC genes were amplified in 110 S. aureus and 59 CNS isolates and prevalence compared in isolates from ortho-k lens and spectacle wearers. Associations were assessed between presence of QAC genes and antibiotic and antiseptic susceptibility. Although isolation of S. aureus did not differ significantly in periorbital samples from ortho-k and control subjects, QAC genes were significantly more common in both S. aureus and CNS from ortho-k subjects (odds ratio 4.4 and 10.74, respectively). Overall, qacA/B was the predominant gene detected, being present in 26.5% CNS and 11% S. aureus. smr and qacH were present in 12% of CNS, but were less common in S. aureus. QAC gene-positive isolates had higher MICs to benzalkonium chloride and chlorhexidine digluconate. Our results suggest that long-term use of multipurpose solutions containing quaternary ammonium compounds may select for carriage of organisms harboring QAC genes. As these genes are associated with antibiotic resistance, their increased prevalence in isolates from contact lens wearers is a concern.

Antimicrobial resistance in coagulase-positive staphylococci isolated from companion animals in Australia: A one year study.

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Sugiyono Saputra

Full Text Available Methicillin-resistant coagulase-positive staphylococci (CoPS have become increasingly recognised as opportunistic pathogens that limit therapeutic options in companion animals. The frequency of methicillin resistance amongst clinical isolates on an Australia-wide level is unknown. This study determined antimicrobial susceptibility patterns for CoPS isolated from clinical infections in companion animals (dogs, cats and horses as part of the first nation-wide survey on antimicrobial resistance in animal pathogens in Australia for a one-year period (January 2013 to January 2014. Clinical Staphylococcus spp. isolates (n = 888 obtained from 22 veterinary diagnostic laboratories were identified by MALDI-TOF mass spectrometry and subjected to antimicrobial susceptibility testing for 16 antimicrobials, representing 12 antimicrobial classes. Potential risk factors associated with methicillin resistance in Staphylococcus pseudintermedius isolates from dogs were analysed based on demographic factors and clinical history, including gender, age, previous antimicrobial treatment, chronic and/or recurrent diseases and site of infections. The most commonly identified CoPS were S. pseudintermedius (70.8%; dogs n = 616, cats n = 13 and S. aureus (13.2%, horses n = 53, dogs n = 47 and cats n = 17. Overall, the frequency of methicillin resistance among S. pseudintermedius (MRSP and S. aureus (MRSA was 11.8% and 12.8%, respectively. MRSP isolates were strongly associated with resistance to fluoroquinolones (OR 287; 95%CI 91.2-1144.8 and clindamycin (OR 105.2, 95%CI 48.5-231.9. MRSA isolates from dogs and cats were also more likely to be resistant to fluoroquinolones (OR 5.4, 95%CI 0.6-252.1, whereas MRSA from horses were more likely to be resistant to rifampicin. In multivariate analysis, MRSP-positive status was significantly associated with particular infection sites, including surgical (OR 8.8; 95%CI 3.74-20.7, and skin and soft tissue (OR 3.9; 95%CI 1.97-7.51. S

Acute Bacterial Meningitis in Qatar: A Hospital-Based Study from 2009 to 2013.

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Khan, Fahmi Yousef; Abu-Khattab, Mohammed; Almaslamani, Eman Abdulrahman; Hassan, Abubaker Ahmed; Mohamed, Shehab Fareed; Elbuzdi, Abdurrahman Ali; Elmaki, Nada Yagoub; Anand, Deshmukh; Sanjay, Doiphode

2017-01-01

Bacterial meningitis is a common medical condition in Qatar. The aim of this study was to describe the clinical characteristics of bacterial meningitis, the frequency of each pathogen, and its sensitivity to antibiotics and risk factors for death. This retrospective study was conducted at Hamad General Hospital between January 1, 2009, and December 31, 2013. We identified 117 episodes of acute bacterial meningitis in 110 patients. Their mean age was 26.4 ± 22.3 years (range: 2-74) and 81 (69.2%) of them were male patients. Fifty-nine episodes (50.4%) were community-acquired infection and fever was the most frequent symptom (94%), whereas neurosurgery is the most common underlying condition. Coagulase-negative staphylococci were the most common causative agent, of which 95% were oxacillin-resistant, while 63.3% of Acinetobacter spp. showed resistance to meropenem. The in-hospital mortality was 14 (12%). Only the presence of underlying diseases, hypotension, and inappropriate treatment were found to be independent predictors of mortality. Acute bacterial meningitis predominantly affected adults and coagulase-negative staphylococci species were the common causative agent in Qatar with majority of infections occurring nosocomially. More than 90% of all implicated coagulase-negative staphylococci strains were oxacillin-resistant.

Acute Bacterial Meningitis in Qatar: A Hospital-Based Study from 2009 to 2013

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Fahmi Yousef Khan

2017-01-01

Full Text Available Background and Objectives. Bacterial meningitis is a common medical condition in Qatar. The aim of this study was to describe the clinical characteristics of bacterial meningitis, the frequency of each pathogen, and its sensitivity to antibiotics and risk factors for death. Patients and Methods. This retrospective study was conducted at Hamad General Hospital between January 1, 2009, and December 31, 2013. Results. We identified 117 episodes of acute bacterial meningitis in 110 patients. Their mean age was 26.4±22.3 years (range: 2–74 and 81 (69.2% of them were male patients. Fifty-nine episodes (50.4% were community-acquired infection and fever was the most frequent symptom (94%, whereas neurosurgery is the most common underlying condition. Coagulase-negative staphylococci were the most common causative agent, of which 95% were oxacillin-resistant, while 63.3% of Acinetobacter spp. showed resistance to meropenem. The in-hospital mortality was 14 (12%. Only the presence of underlying diseases, hypotension, and inappropriate treatment were found to be independent predictors of mortality. Conclusion. Acute bacterial meningitis predominantly affected adults and coagulase-negative staphylococci species were the common causative agent in Qatar with majority of infections occurring nosocomially. More than 90% of all implicated coagulase-negative staphylococci strains were oxacillin-resistant.

Fusidic acid resistance among staphylococci strains isolated from clinical specimens

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Özcan Deveci

2012-03-01

Full Text Available Objectives: The aim of this study was to investigate in vitrosusceptibility of fusidic acid to clinic isolates of staphylococci.Materials and methods: The forty-one coagulase negativestaphylococci (CNS and 18 Staphylococcus aureusstrains isolated from various clinical specimens were includedin this study. Staphylococci isolates were identifiedby conventional methods such as colony morphologyonto medium, gram staining, catalase and coagulasetests. According to “Clinical and Laboratory Standards Institute(CLSI” criteria, antimicrobial susceptibility testingof isolates was performed by Kirby-Bauer’s disk diffusionmethod.Results: The seventy-two percent of the isolated S.aureuswere defined as methicillin sensitive-S.aureus (MSSA,28% of the isolated S.aureus were defined as methicillinresistant-S.aureus (MRSA. The difference among fusidicacid susceptibility rates of MSSA and MRSA strains wasnot statistically significant (p=0.305. The twenty-nine percentof the isolated CNS were defined as methicillin sensitive-CNS (MS-CNS, 71% of the isolated CNS were definedas methicillin resistant-CNS (MR-CNS. There wasno statistically significant difference between MS-CNSand MR-CNS strains for fusidic acid susceptibility rates(p=0.490. But the difference among fusidic acid susceptibilityrates of CNS and S.aureus strains was statisticallysignificant (p<0.001. CNS strains were found more resistancethan S.aureus strains for fusidic acid.Conclusion: In this study, the resistance rates weredetected to increase for fusidic acid along with methicillinresistance. Among CNS isolates, fusidic acid resistancerates were significantly more elevated than that forS.aureus. Fusidic acid remains as an alternative in thetreatment of infections due to staphylococci.

The importance of staphylococci and threshold value of somatic cell count for diagnosis of sub-clinical mastitis in Pirlak sheep at mid-lactation.

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Ozenc, E; Seker, E; Baki Acar, D; Birdane, M K; Darbaz, I; Dogan, N

2011-12-01

This study investigated the bacterial agents causing sub-clinical mastitis and the mean somatic cell counts (SCC) of milk in Pirlak sheep at mid-lactation. The percentage of infected udder halves was 11.4% (53/464). The most frequently isolated species were coagulase-negative staphylococci (CNS) (64.2%), followed by Staphylococcus aureus (24.5%) and Escherichia coli (11.3%). Among the CNS, the most common species was Staphylococcus epidermidis (38.2%). The other species isolated from milk samples were Staphylococcus xylosus (17.7%), Staphylococcus chromogenes (14.7%), Staphylococcus simulans (8.8%) and Staphylococcus hyicus (8.8%). The mean SCC for culture positive and negative samples was 1742×10(3) and 161×10(3) cells/ml, respectively. A significant difference (pmastitis in Pirlak sheep. This is the first study to describe the bacterial agents causing sub-clinical mastitis and threshold limit for SCC in Pirlak sheep in Turkey. © 2011 Blackwell Verlag GmbH.

Study on Prevalence, Antibiotic Susceptibility, and tuf Gene Sequence-Based Genotyping of Species-Level of Coagulase-Negative Staphylococcus Isolated From Keratitis Caused by Using Soft Contact Lenses.

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Faghri, Jamshid; Zandi, Alireza; Peiman, Alireza; Fazeli, Hossein; Esfahani, Bahram Nasr; Safaei, Hajieh Ghasemian; Hosseini, Nafiseh Sadat; Mobasherizadeh, Sina; Sedighi, Mansour; Burbur, Samaneh; Oryan, Golfam

2016-03-01

To study on antibiotic susceptibility and identify coagulase-negative Staphylococcus (CoNS) species based on tuf gene sequencing from keratitis followed by using soft contact lenses in Isfahan, Iran, 2013. This study examined 77 keratitis cases. The samples were cultured and the isolation of CoNS was done by phenotypic tests, and in vitro sensitivity testing was done by Kirby-Bauer disk diffusion susceptibility method. Thirty-eight of isolates were conveniently identified as CoNS. In this study, 27 (71.1%), 21 (55.3%), and 16 (42.1%) were resistant to penicillin, erythromycin, and tetracycline, respectively. One hundred percent of isolates were sensitive to gentamicin, and 36 (94.7%) and 33 (86.8%) of isolates were sensitive to chloramphenicol and ciprofloxacin, respectively. Also, resistances to cefoxitin were 7 (18.4%). Analysis of tuf gene proved to be discriminative and sensitive in which all the isolates were identified with 99.0% similarity to reference strains, and Staphylococcus epidermidis had the highest prevalence among other species. Results of this study showed that CoNS are the most common agents causing contact lens-associated microbial keratitis, and the tuf gene sequencing analysis is a reliable method for distinguishing CoNS species. Also gentamycin, chloramphenicol, and ciprofloxacin are more effective than the other antibacterial agents against these types of bacteria.

Species identification, slime production and oxacillin susceptibility in coagulase-negative staphylococci isolated from nosocomial specimens Identificação de espécies, produção de "slime" e sensibilidade a oxacilina em amostras de Staphylococcus coagulase-negativo isoladas de espécimes nosocomiais

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Lucía E. Alcaráz

2003-04-01

Full Text Available Ninety-two coagulase negative staphylococci (CNS (forty-five of clinical origin and forty-seven of environmental origin, collected in a hospital in San Luis, Argentina, from March to June, 1999, were identified to species level by the ID 32 Staph and API Staph System (bioMérieux. Slime production was investigated by the quantitative and qualitative methods. Oxacillin susceptibility was determined by the disk diffusion test (1 µg, the agar dilution method (0.125 to 4 mg/ml and agar screen (6 µg/ml. The presence of mecA gene was investigated by PCR. The clinical CNS species most commonly isolated were S. epidermidis, S. haemolyticus, S. hominis and S. saprophyticus. The frequency of slime production by clinical and environmental isolates was similar (25/45 and 27/47, respectively and the results obtained by the quantitative and the qualitative methods correlated well. The mecA gene was detected in all S. epidermidis, S. haemolyticus and S. hominis isolates, which were resistant to oxacillin by the phenotypic methods. However, this gene was not present in S. klossii, S. equorum, S. xylosus and S. capitis strains. The gene was neither found in two out of the six S. saprophyticus isolates, in two out of three S. cohnii subsp. urealyticum isolates and in two out of five S. cohnii subsp. cohnii isolates, all of which resulted oxacillin resistant according to MIC. The gene was not found in oxacillin-susceptible strains either. Most of the CNS isolates (enviromental and clinical that were slime producers were found to be oxacillin resistant, which makes the early detection of these microorganisms necessary to prevent their dissemination in hospitals, particularly among immunocompromised patients.Noventa e duas amostras de Staphylococcus coagulase negativo (SCN, (45 amostras clínicas e 47 ambientais, coletadas em um hospital de San Luis, Argentina, durante o período de março a junho de 1999, foram identificadas até espécies, empregando-se os

Prevalence of microorganisms associated with udder infections in dairy goats on small-scale farms in Kenya : short communication

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E.N. Ndegwa

2001-07-01

Full Text Available Six hundred and thirty clinically-normal milk samples from dairy goat flocks comprising a mixed population of German Alpine, Toggenburg, Saanen and Galla crosses were exam-ined over a 3-month period to determine the prevalence of bacterial organisms. Bacteria were isolated in 28.7 % of the milk samples (181/630 either singly (92.8 % or in combination (7.2 %. The most prevalent bacterial organisms were Staphylococcus spp. (60.3 %, followed by Micrococcus spp. (17.7 %, Acinetobacter spp. (5 %, Actinomyces spp. (5% and Streptococcus spp. (1.1 %. The Staphylococcus spp. were mainly coagulase negative (64.3 %. Coagulase-- negative staphylococci and coagulase-positive staphylococci accounted for 37.5 % and 22.7 % respectively of the total bacteria isolated. The isolation of bacteria, some of which are important in clinical and subclinical mastitis, in apparently normal caprine milk, indicates that particular attention should be given to the management of these dairy goat flocks in order to avoid the development of cases of clinical mastitis.

Prevalence and antibiotic susceptibility of coagulase-negative Staphylococcus species from bovine subclinical mastitis in dairy herds in the central region of Argentina.

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Raspanti, Claudia G; Bonetto, Cesar C; Vissio, Claudina; Pellegrino, Matías S; Reinoso, Elina B; Dieser, Silvana A; Bogni, Cristina I; Larriestra, Alejandro J; Odierno, Liliana M

2016-01-01

Coagulase-negative staphylococci (CNS) are a common cause of bovine subclinical mastitis (SCM). The prevalence of CNS species causing SCM identified by genotyping varies among countries. Overall, the antimicrobial resistance in this group of organisms is increasing worldwide; however, little information exists about a CNS species resistant to antibiotics. The aim of the present study was to genotypically characterize CNS at species level and to determine the prevalence and antibiotic resistance profiles of CNS species isolated from bovine SCM in 51 dairy herds located in the central region of the province of Cordoba, Argentina. In this study, we identified 219 CNS isolates at species level by PCR-restriction fragment length polymorphism of the groEL gene. Staphylococcus chromogenes (46.6%) and Staphylococcus haemolyticus (32%) were the most prevalent species. A minimum of three different CNS species were present in 41.2% of the herds. S. chromogenes was isolated from most of the herds (86.3%), whereas S. haemolyticus was isolated from 66.7% of them. The broth microdilution method was used to test in vitro antimicrobial susceptibility. Resistance to a single compound or two related compounds was expressed in 43.8% of the isolates. S. chromogenes and S. haemolyticus showed a very high proportion of isolates resistant to penicillin. Resistance to two or more non-related antimicrobials was found in 30.6% of all CNS. S. haemolyticus exhibited a higher frequency of resistance to two or more non-related antimicrobials than S. chromogenes. Copyright © 2016 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Bacterial subclinical mastitis and its effect on milk yield in low-input dairy goat herds.

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Gelasakis, A I; Angelidis, A S; Giannakou, R; Filioussis, G; Kalamaki, M S; Arsenos, G

2016-05-01

The objectives of this study were (1) to record the major pathogens associated with subclinical mastitis (SCM), (2) to calculate their incidence during the milking period, and (3) to estimate the effect of SCM on daily milk yield (DMY) for goats reared under low-input management schemes. Dairy goats (n=590) of Skopelos and indigenous Greek breeds from 4 herds were randomly selected for the study. The study included monthly monitoring, milk yield recording, and bacteriological analyses of milk of individual goats during the course of 2 successive milking periods. Incidence and cumulative incidence were calculated for SCM cases. Moreover, 2 mixed linear regression models were built to assess the effects of (1) SCM and (2) different pathogens isolated from SCM cases, on DMY. The estimated incidence and cumulative incidence of SCM for the first and the second year of the study were 69.5 and 96.4 new cases of SCM/1,000 goat-months, and 24.1 and 31.7%, respectively. A total of 755 milk samples were subjected to microbiological examination, resulting in 661 positive cultures. Coagulase-negative and coagulase-positive staphylococci were isolated from 50.2 and 34.5% of the positive cultures, respectively. The incidence of infections (new infections per 1,000 goat-months) for the first and the second year of the study were 34 and 53 for coagulase-negative staphylococci, 23 and 28 for coagulase-positive staphylococci, 3 and 5 for Streptococcus/Enterococcus spp., and 5.5 and 9.1 for gram-negative bacteria. Goats with SCM had lower DMY when compared with goats without SCM (ca. 47g/d, corresponding to a 5.7% decrease in DMY). In particular, goats with SCM due to coagulase-positive staphylococci infection produced approximately 80g/d less milk (a reduction of ca. 9.7%) compared with uninfected ones, whereas SCM due to gram-negative bacteria resulted in approximately 15% reduction in DMY. Investigating the epidemiology of SCM and its effects on production traits is critical for

Risk Factors for Nasal Colonization by Methicillin-Resistant Staphylococci in Healthy Humans in Professional Daily Contact with Companion Animals in Portugal.

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Rodrigues, Ana Catarina; Belas, Adriana; Marques, Cátia; Cruz, Luís; Gama, Luís T; Pomba, Constança

2018-05-01

Methicillin-resistant staphylococci (MRS), namely Staphylococcus aureus (MRSA) and Staphylococcus pseudintermedius (MRSP), are opportunistic agents of great importance in human and veterinary medicine. The aims of this study were to investigate the frequency, persistence, and risk factors associated with nasal colonization by MRS in people in daily contact with animals in Portugal. Seventy-nine out of 129 (61.2%) participants were found to be colonized by, at least, one methicillin-resistant (MR) staphylococci species (MR Staphylococcus epidermidis [n = 68], MRSA [n = 19], MR Staphylococcus haemolyticus [n = 7], MRSP [n = 2], and other coagulase-negative staphylococci [n = 4]). Three lineages were identified among the MRSA isolates (n = 7): the major human healthcare clone in Portugal (ST22-t032-IV, n = 3), the livestock-associated MRSA (ST398-t108-V, n = 3), and the New York-/Japan-related clone (ST105-t002-II, n = 1). MRSP isolates belonged to the European clone ST71-II-III. We identified two risk factors for nasal colonization by MRS in healthy humans: (i) being a veterinary professional (veterinarian and veterinary nurse) (p < 0.0001, odds ratio [OR] = 6.369, 95% confidence interval [CI, 2.683-15.122]) and (ii) have contacted with one MRSA- or MRSP-positive animal (p = 0.0361, OR = 2.742, 95% CI [1.067-7.045]). The follow-up study revealed that the majority (85%) remain colonized. This study shows that MRS in veterinary clinical practice is a professional hazard and highlights the need to implement preventive measures to minimize spread.

Laboratory detection methods for methicillin resistance in coagulase negative Staphylococcus isolated from ophthalmic infections Métodos laboratoriais para a detecção da resistência à meticilina nos Staphylococcus coagulase negativos de infecções oculares

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Adália Dias Dourado Oliveira

2007-08-01

Full Text Available PURPOSE: To evaluate different methods of oxacillin susceptibility testing of ocular isolates, considering polymerase chain reaction (PCR as the 'gold standard', and to compare the in vitro susceptibility to oxacillin with that of other antimicrobials used in ophthalmologic practice. METHODS: The Vitek gram-positive identification card was used to identify ocular coagulase negative Staphylococcus species. The presence of the mecA gene was determined by the polymerase chain reaction assay with a combination of two primer sets (mecA and 16S rRNA in a single region. Results were analyzed and compared with other oxacillin susceptibility methods: PBP2a detection by rapid slide latex agglutination test (SLA; oxacillin E-test; the Vitek automated gram-positive susceptibility card (GPS-105; the oxacillin salt agar screening test (OSAS at a concentration of 6.0, 1.0 and 0.75 µg oxacillin per ml and the cefoxitin disk diffusion test (CDD. Automated susceptibility was also determined to other antimicrobial agents (fluoroquinolones, penicillin G, amoxicillin-ampicillin, cefazolin, ampicillin-sulbactam, erythromycin, clindamycin, gentamicin, tetracycline, trimethoprim-sulfamethoxazole, vancomycin and rifampin. RESULTS: Of the 69 CoNS isolates tested, 71% were mecA-positive and 29% mecA-negative. All methods tested had a statistically significant agreement with polymerase chain reaction. There was a tendency of positive polymerase chain reaction predomination among the S. epidermidis isolates in comparison to non-epidermidis isolates, although this was not statistically significant (78.3% vs. 56.5%; chi2= 2.54; P= 0.11. The oxacillin salt agar screening test (0.75 µg oxacillin/ml showed the best performance, with 100% sensitivity and negative predictive value; 95% specificity and 98% positive predictive value. Using the E-test, the mecA-positive isolates were statistically significantly more resistant to ciprofloxacin, ofloxacin, gatifloxacin and

Incidenza della meticillino-resistenza in Staphylococcus aureus e stafilococchi coagulasi-negativi isolati da emocolture

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Alessandra Siddi

2007-12-01

Full Text Available Background: Staphylococci are major cause of nosocomial blood stream infections.This local surveillance study was carry out to monitor frequency of occurrence of Staphylococcus aureus and coagulase-negative staphylococci (CoNS in blood stream infections and the incidence of methicillin-resistant (MET-R strains. Materials and methods: During the period January – December 2006, 9840 blood specimens were analyzed and microrganisms from positive samples were collected. Bacterial identifications were performed according to the standard methods (Murray, 2003.We evaluated, in particular, the antibiotic-resistance phenotype of staphylococci employing disk diffusion test as suggested by the CLSI (2006. The following antimicrobial agents were tested: oxacillin, penicillin, amoxiciclin-clavulanate, cefalotin, cefamandole, imipenem, teicoplanin, linezolid, ciprofloxacin, erythromycin, clindamicin, rifampicin, trimethoprim-sulfamethoxazole, gentamicin, doxiciclin, fosfomycin. Results: The microrganisms isolated were 551: 370 Gram-positives (67%, 131 Gram-negatives (24%, 11 anaerobes (2% and 39 mycetes (7%. In particular, 121 S. epidermidis, 75 S. aureus, 42 S. haemolyticus and other 39 CoNS were analyzed: methicillin-resistance occurred in more than 80% of S.aureus strains collected from Intensive Care Units (ICU and in about 50 % of those isolated from other divisions. In CoNS the incidence of MET-R ranged from 30 to 80 %, the higher values were registered among S. epidermidis and S. haemolyticus. MET-R strains were characterized by high resistance rates even to ciprofloxacin (from 47 to 100%, erythromycin (from 70 to 100%, and in same cases to gentamicin (from 23 to 86% also. Conclusions: Staphylococci are the prevalent cause of blood stream infections.The distinctive feature of MET-R strains is their resistance not only to all b-lactam antibiotics, but also to a wide range of other antimicrobial agents. However, the glycopeptide teicoplanin remains 100

The evolutionary pathway of the staphylococcal cassette chromosome element

Czech Academy of Sciences Publication Activity Database

Indrakova, A.; Mašlaňová, I.; Kováčová, Viera; Doškař, J.; Pantůček, R.

2016-01-01

Roč. 71, č. 11 (2016), s. 1195-1203 ISSN 0006-3088 Institutional support: RVO:68081707 Keywords : coagulase-negative staphylococci * aureus st398 * maximum-likelihood * genome sequence Subject RIV: BO - Biophysics Impact factor: 0.759, year: 2016

Detection of mastitis pathogens by analysis of volatile bacterial metabolites

NARCIS (Netherlands)

Hettinga, K.A.; Valenberg, van H.J.F.; Lam, T.J.G.M.; Hooijdonk, van A.C.M.

2008-01-01

The ability to detect mastitis pathogens based on their volatile metabolites was studied. Milk samples from cows with clinical mastitis, caused by Staphylococcus aureus, coagulase-negative staphylococci, Streptococcus uberis, Streptococcus dysgalactiae, and Escherichia coli were collected. In

Comparison phenotypic and genotypic identification of Staphylococcus species isolated from bovine mastitis

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Felipe Freitas Guimarães

Full Text Available ABSTRACT: In addition to Staphylococcus aureus nowadays other coagulase-positive staphylococci (CoPS and coagulase-negative staphylococci (CoNS, earlier considered of minor importance, are now accepted as relevant pathogens for humans and animals. The involvement of these microorganisms in bovine mastitis etiology and the possibility their transmission through milk to humans justify the requirement of developing reliable methods for identification of the most frequent species among them. The purpose of this study was to compare the phenotypic techniques with the genotypic method carried out by sequencing of the rpoB gene in identification of several species of the genus Staphylococcus isolated from bovine mastitis. A total of 300 staphylococci isolates of bovine mastitis cases from several Brazilian dairy herds were studied by phenotypic and genotypic techniques, respectively: 150 CoPS and 150 CoNS strains. A total of 18 CoNS different species and 4 CoPS species were identified. Among the CoNS the following species were recognized: 48 (32% Staphylococcus warneri, 22(15% S. epidermidis, 20(13% S. hyicus, 10(7% S. xylosus, 7(5% S. haemolyticus, 6(4% S. simulans, 6(4% S. schleiferi subsp schleiferi, 6(4% S. hominis, 5(3% S. pasteuri, 4(2.7% S. cohnii, 3(2% S. saprophyticus subsp. saprophyticus 3(2% S. chromogenes 3(2% S. sciuri, 2(1% S. saccharolyticus, 2(1% S. lugdunensi, 1(0,7% S. auricularis, 1(70% S. saprophyticus subsp. bovis, 1(0.7% S. capitis. And among the 150 CoPS were identified respectively: 105 (70% S. aureus, 21(14%, S. hyicus, 19(13% S. intermedius e 5(3% S. schleiferi subsp coagulans. Considering the 150 CoNS isolates, the identifications performed by phenotypic and genotypic tests presented 96.7% of concordance, kappa coefficient of agreement = 0.933, SE (standard error of kappa=0.021 (95% confidence interval: 0.893 to 0.974, Pearson’s correlation coefficient (r = 0.9977, (confidence interval 95%: 0.9938 a 0.9992 and in relation

Increases of Antibiotic Resistance in Excessive Use of Antibiotics in Smallholder Dairy Farms in Northern Thailand

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W. Suriyasathaporn

2012-09-01

Full Text Available Antibiotic resistance patterns of bacterial isolates from both quarter teat-tip swabs and their quarter milk samples were evaluated in smallholder dairy farms in northern Thailand with excessive use of antibiotics (HIGH compared with normal use (NORM. Results from teat-tip swab samples showed that the percentage of Bacillus spp. resistance to overall antibiotics was significantly lower in the NORM group than that of the HIGH group, whereas, the resistance percentage of coagulase-negative staphylococci in the NORM group was higher than that of the HIGH one. The overall mastitis-causing bacteria isolated from milk samples were environmental streptococci (13.8%, coagulase-negative staphylococci (9.9%, Staphylococcus aureus (5.4%, and Corynebacterium bovis (4.5%. Both staphylococci and streptococci had significantly higher percentages of resistance to cloxacillin and oxacillin in the HIGH group when compared to the NORM one. An occurrence of vancomycin-resistant bacteria was also observed in the HIGH group. In conclusion, the smallholder dairy farms with excessive use of antibiotics had a higher probability of antibiotic-resistant pattern than the farms with normal use.

Characterization of Staphylococcus species isolated from raw milk and milk products (lben and jben) in North Morocco.

Science.gov (United States)

Bendahou, Abdrezzak; Lebbadi, Mariam; Ennanei, Latifa; Essadqui, Fatima Z; Abid, Mohammed

2008-06-01

To investigate the incidence and antibiotic resistance of staphylococcal strains isolated from milk and milk products and to trace the ecological origin of the Staphylococcus aureus isolated. Eighty-one samples of raw milk, lben (whey) and jben (cheese) were analyzed for the presence of staphylococcal strains. Isolates were identified by Gram stains, tests for coagulase, the API staph system and the WalkAway 40/96, which also determines the antimicrobial susceptibility profiles. The S. aureus strains were biotyped, and variable regions of the coagulase gene were amplified using the polymerase chain reaction. The identification results showed a predominance of coagulase-negative staphylococci (54 %). Coagulase-positive staphylococci that were identified were divided into 3 groups comprising S. aureus (40%), Staphylococcus intermedius (2 %) and Staphylococcus hyicus (4%). Among the S. aureus that was isolated, biotype C was the predominant biotype. Among 40 coagulase gene PCR-amplification products, 37 produced a single band, while 3 isolates produced two bands. The antimicrobial susceptibility-profile of the staphylococcal strains revealed a high incidence of S. aureus to penicillin G. In addition, Staphylococcus lentus presented considerable resistance to the oxacillin, erythromycin and lincomycin. The presence of staphylococci in raw milk, lben and jben in areas of northern Morocco poses a health hazard, so it is necessary for the public health inspectors to properly examine the conditions during production, storage and commercialization of all products made with unpasteurized milk.

Staphylococcus cohnii: a case report on an unusual pathogen.

Science.gov (United States)

Fernandes, A P; Perl, T M; Herwaldt, L A

1996-01-01

Coagulase-negative staphylococci have become increasingly important causes of infection in predisposed hosts. such as patients receiving immunosuppressive therapy and broad-spectrum antimicrobial drugs, patients who have prosthetic devices, or those who have prolonged hospital or intensive care unit stays. However, human infections caused by Staphylococcus cohnii rarely have been reported in the literature. In this report, we review the current literature and describe a 38 year-old immunosuppressed woman who developed catheter-related S. cohnii bacteremia. The case illustrates why microbiology laboratories under certain circumstances should identify coagulase-negative staphylococci to the species level. This information may be critical because it may allow clinicians to identify the source of the infecting organism and to choose appropriate antibiotics. Yet in this era of cost containment many laboratories may decrease costs by decreasing services, including species identification.

HEALTH AND HYGIENIC CONDITIONS OF EWE'S MILK PROCESSING FROM THE ASPECT OF FOOD SAFETY

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Jana Pukáčová

2010-07-01

Full Text Available Totally, 47 strains of S. aureus and 578 coagulase negative staphylococci were detected in samples from raw ewe milk. The 35 out 47 isolates of S. aureus from ewe milk were positive for the presence of staphylococcal enterotoxin genes: sea(4 %, sec (48 % a sed (48 %. Staphylococcus epidermis (33.04%, Staphylococcus caprae (21.28% were more prevalent. Staphylococcus chromogenes (7.44 %, Staphylococcus hominis (7.09%, Staphylococcus xylosus (6,92 %, a Staphylococcus warneri (6.40 % were isolated also in ewes milk. Staphylococcus haemolyticus (3.11 %, Staphylococcus capitis (2.94 %, Staphylococcus simulans (2.08 % and Staphylococcus saprophyticus (1.73 % were isolated very rarely from the taken individual milk ewe samples. Sporadically, only in few cases, the others coagulase negative staphylococci were isolated (Staphylococcus cohnii cohnii, Staphylococcus sciuri, Staphylococcus closii, Staphylococcus lugdunensis, Staphylococcus auricularis and Staphylococcus equorum.   doi:10.5219/24

Detection of mastitis pathogens by analysis of volatile bacterial metabolites.

Science.gov (United States)

Hettinga, K A; van Valenberg, H J F; Lam, T J G M; van Hooijdonk, A C M

2008-10-01

The ability to detect mastitis pathogens based on their volatile metabolites was studied. Milk samples from cows with clinical mastitis, caused by Staphylococcus aureus, coagulase-negative staphylococci, Streptococcus uberis, Streptococcus dysgalactiae, and Escherichia coli were collected. In addition, samples from cows without clinical mastitis and with low somatic cell count (SCC) were collected for comparison. All mastitis samples were examined by using classical microbiological methods, followed by headspace analysis for volatile metabolites. Milk from culture-negative samples contained a lower number and amount of volatile components compared with cows with clinical mastitis. Because of variability between samples within a group, comparisons between pathogens were not sufficient for classification of the samples by univariate statistics. Therefore, an artificial neural network was trained to classify the pathogen in the milk samples based on the bacterial metabolites. The trained network differentiated milk from uninfected and infected quarters very well. When comparing pathogens, Staph. aureus produced a very different pattern of volatile metabolites compared with the other samples. Samples with coagulase-negative staphylococci and E. coli had enough dissimilarity with the other pathogens, making it possible to separate these 2 pathogens from each other and from the other samples. The 2 streptococcus species did not show significant differences between each other but could be identified as a different group from the other pathogens. Five groups can thus be identified based on the volatile bacterial metabolites: Staph. aureus, coagulase-negative staphylococci, streptococci (Strep. uberis and Strep. dysgalactiae as one group), E. coli, and uninfected quarters.

Genetic correlations between pathogen-specific mastitis and somatic cell count in Danish Holsteins

DEFF Research Database (Denmark)

Sørensen, Lars Peter; Mark, Thomas; Madsen, P.

2009-01-01

_170) or 300 d (LASCC_300) after calving, and the mastitis traits were unspecific mastitis (all mastitis treatments, both clinical and subclinical, regardless of the causative pathogen) and mastitis caused by either Streptococcus dysgalactiae, Escherichia coli, coagulase-negative staphylococci (CNS...

Antibiotic Exposure in a Low-Income Country: Screening Urine Samples for Presence of Antibiotics and Antibiotic Resistance in Coagulase Negative Staphylococcal Contaminants

DEFF Research Database (Denmark)

Lerbeck, Anne Mette; Tersbøl, Britt Pinkowski; Styrishave, Bjarne

2014-01-01

for the determination of the nine most commonly used antimicrobial agents in Ghana by using solid-phase extraction in combination with HPLC-MS/MS using electron spray ionization. The highest frequency of resistance to CoNS was observed for penicillin V (98%), trimethoprim (67%), and tetracycline (63%). S. haemolyticus......596 respectively) from patients in two hospitals in Ghana. CoNS were identified using Gram staining, coagulase test, and MALDI-TOF/MS, and the antimicrobial susceptibility to 12 commonly used antimicrobials was determined by disk diffusion. Moreover an analytical method was developed...... agents were detected in 64% of the analysed urine samples (n5121) where the most frequently detected antimicrobials were ciprofloxacin (30%), trimethoprim (27%), and metronidazole (17%). The major findings of this study was that the prevalence of detected antimicrobials in urine was more frequent than...

Prevalence of Genotypes That Determine Resistance of Staphylococci to Macrolides and Lincosamides in Serbia

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Milena Mišić

2017-08-01

Full Text Available Macrolides, lincosamides, and streptogramins (MLS resistance genes are responsible for resistance to these antibiotics in Staphylococcus infections. The purpose of the study was to analyze the distribution of the MLS resistance genes in community- and hospital-acquired Staphylococcus isolates. The MLS resistance phenotypes [constitutive resistance to macrolide–lincosamide–streptogramin B (cMLSb, inducible resistance to macrolide–lincosamide–streptogramin B (iMLSb, resistance to macrolide/macrolide–streptogramin B (M/MSb, and resistance to lincosamide–streptogramin A/streptogramin B (LSa/b] were determined by double-disc diffusion method. The presence of the MLS resistance genes (ermA, ermB, ermC, msrA/B, lnuA, lnuB, and lsaA were determined by end-point polymerase chain reaction in 179 isolates of staphylococci collected during 1-year period at the Center for Microbiology of Public Health Institute in Vranje. The most frequent MLS phenotype among staphylococcal isolates, both community-acquired and hospital-acquired, was iMLSb (33.4%. The second most frequent was M/MSb (17.6% with statistically significantly higher number of hospital-acquired staphylococcal isolates (p < 0.05. MLS resistance was mostly determined by the presence of msrA/B (35.0% and ermC (20.8% genes. Examined phenotypes were mostly determined by the presence of one gene, especially by msrA/B (26.3% and ermC (14.5%, but 15.6% was determined by a combination of two or more genes. M/MSb phenotype was the most frequently encoded by msrA/B (95.6% gene, LSa/b phenotype by lnuA (56.3% gene, and iMLSb phenotype by ermC (29.4% and ermA (25.5% genes. Although cMLSb phenotype was mostly determined by the presence of ermC (28.9%, combinations of two or more genes have been present too. This pattern was particularly recorded in methicillin-resistant Staphylococcus aureus (MRSA (58.3% and methicillin-resistant coagulase-negative staphylococci (MRCNS (90.9% isolates with c

Pathogen group specific risk factors at herd, heifer and quarter levels for intramammary infections in early lactating dairy heifers

NARCIS (Netherlands)

Piepers, S.; Peeters, K.; Opsomer, G.; Barkema, H.W.; Frankena, K.; Vliegher, de S.

2011-01-01

Risk factors for intramammary infections caused by coagulase-negative staphylococci, contagious major pathogens and environmental major pathogens in early lactating heifers were evaluated at the herd, heifer and quarter levels. In total, 764 quarters of 191 dairy heifers in 20 randomly selected

Microbiological Findings in Ready-to-Eat and Precooked Food Distributed in Public Catering Halls in Cagliari Province, Italy.

Science.gov (United States)

Brignardello, Silvana; Sabiu, Rosangela; Tedde, Tiziana; Cocco, Enrica; Pitzalis, Gabriella; Meli, Clara; Cogoni, Maria Paola

2014-08-28

During this research 159 samples of ready-to-eat and precooked food were examined for the detection of Salmonella spp., Listeria monocytogenes , Escherichia coli , coagulase-positive staphylococci and Enterobacteriaceae , bacterial count. All samples were negative for Salmonella spp. and Listeria monocytogenes ; although a low count of coagulase-positive staphylococci (no. 5 samples) and E. coli (no. 3) was found. We proceeded with the identification of the isolates on every sample with high, moderate and low-count of Enterobacteriaceae , to better understand the microbial ecology. The Enterobacteriaceae species most frequently detected were Pantoea spp. (29.62%), Enterobacter cloacae (20.37%) and Serratia liquefaciens (12.96%); other different species of Enterobacteriaceae were detected with a ready-to-eat and precooked food, to proceed with the identification of every microorganism.

Time course of radiometric detection of positive blood cultures in childhood

International Nuclear Information System (INIS)

Meadow, W.L.; Schwartz, I.K.

1986-01-01

We have determined the time course of radiometric detection of microbial growth in 2348 positive blood culture specimens obtained at Wyler Children's Hospital during a 5-year interval. Overall 72 and 88% of isolates were detected within 48 and 72 hours after sampling, respectively. For pathogenic organisms aerobic detection was generally more rapid and more inclusive than anaerobic detection. At 48 hours of incubation the detection of six potential pathogens (Salmonella sp., Haemophilus influenzae, Group D streptococci, Neisseria meningitidis, coagulase-negative staphylococci, Candida sp.) was significantly delayed compared with detection of other pathogenic organisms recovered from blood. At 72 hours of incubation the detection rates remained less than 95% for H. influenzae, Staphylococcus aureus, Klebsiella sp., coagulase-negative staphylococci, Group D streptococci and Candida sp. These data should assist clinical decisions regarding duration of antibiotic therapy for the presumptive diagnosis of bacteremia in children

Time course of radiometric detection of positive blood cultures in childhood

Energy Technology Data Exchange (ETDEWEB)

Meadow, W.L.; Schwartz, I.K.

1986-05-01

We have determined the time course of radiometric detection of microbial growth in 2348 positive blood culture specimens obtained at Wyler Children's Hospital during a 5-year interval. Overall 72 and 88% of isolates were detected within 48 and 72 hours after sampling, respectively. For pathogenic organisms aerobic detection was generally more rapid and more inclusive than anaerobic detection. At 48 hours of incubation the detection of six potential pathogens (Salmonella sp., Haemophilus influenzae, Group D streptococci, Neisseria meningitidis, coagulase-negative staphylococci, Candida sp.) was significantly delayed compared with detection of other pathogenic organisms recovered from blood. At 72 hours of incubation the detection rates remained less than 95% for H. influenzae, Staphylococcus aureus, Klebsiella sp., coagulase-negative staphylococci, Group D streptococci and Candida sp. These data should assist clinical decisions regarding duration of antibiotic therapy for the presumptive diagnosis of bacteremia in children.

Antimicrobial resistance and production of biofilms in clinical isolates of coagulase-negative Staphylococcus strains.

Science.gov (United States)

de Allori, María Cristina Gaudioso; Jure, María Angela; Romero, Cintia; de Castillo, Marta Elena Cecilia

2006-08-01

Coagulase-negative Staphylococcus (CNS) strains are frequently associated with bacteremia and hospital-acquired infections. 293 CNS strains were isolated from 744 samples from a dialysis center in S. M. de Tucumán, Argentina, from hemocultures, catheters and urine and identified as S. epidermidis, S. haemolyticus, S. saprophyticus, S. hominis and S. cohnii. 13 antibiotics were tested for antibacterial resistance. 75% of S. saprophyticus, 66% of S. epidermidis and 57% of S. haemolyticus was resistant to erythromycin and 50% of S. haemolyticus was resistant to ciprofloxacin. OXA resistance was found in 43% of S. haemolyticus. Presence of PBP 2a in OXA-R strains was confirmed with the modified agglutination assay (MRSA) and presence of the mecA gene. 15 strains with intermediate halos for vancomycin and teicoplanin showed a MIC in solid and liquid medium resistance to methicillin and biofilm production are decisive for a prompt and appropriate antimicrobial therapy and limited use of inappropriate glycopeptides.

Antibacterial properties studies of trunk barks of Terminalia ivorensis, a commercial and medicinal species on some methicillin-resistant Staphylococci species strains.

Science.gov (United States)

Coulibaly, K; Zirihi, G N; Guessennd-Kouadio, N; Oussou, K R; Dosso, M

2014-09-01

Methicillin-resistant Staphylococcus aureus, Staphylococcus epidermidis and coagulase-negative Staphylococcus infections are a worldwide concern. Terminalia ivorensis, of Combretaceae family plant, is widely used traditional medicinal in Côte d'Ivoire to treat dermal diseases (affection in which Staphylococci are implied) including local inflammation and also to treat voice-loss. This study focused to investigate the effect in vitro of the extracts of trunk barks of Terminalia ivorensis on some methicillin/oxacillin-resistant strains of Staphylococcus aureus, S. epidermidis, coagulase-negative S. and reference strain of S. aureus ATCC 25923. Antibacterial activity of aqueous, 70% ethanolic 70% and aqueous residue extracts was assessed using agar disc-diffusion method and liquid medium microdilution method in 96 multi-well micro-titer plates. This method led us to determine minimum inhibition concentration (M.I.C.) and minimum bactericidal concentration (M.B.C.). The presence of chemical groups major was detected qualitatively. Aqueous and 70% ethanolic 70% extracts showed significant activity against all the bacteria except aqueous residue when compared with the standard antibiotic oxacillin (5 µg/ml). M.I.C. for aqueous and 70% ethanolic 70% extracts ranged from 0,83-16,67 mg/ml and 0,156-13,33 mg/ml respectively. Viable cell determination revealed the bactericidal nature of the two barks extracts. The 70% ethanolic 70% extract exhibited the highest activity according to the M.B.C. values. The phytochemical analysis indicates the presence of tannins, saponins, flavonoids, terpen/sterols, coumarins, polyphenols and traces of alkaloid. The in-vitro antibacterial efficacy shown by the barks of this plant and his lushness in chimical compounds, would justify use of this one in the traditional treatment of some diseases of microbial origin. These compounds could be suggested to provide alternative solution to the development of new therapeutic agents.

Bacteremia and candidemia in hematological malignancies

DEFF Research Database (Denmark)

Bruun, B; Bangsborg, Jette Marie; Hovgaard, D

1988-01-01

of coagulase-negative staphylococci was higher in the latter period while that of Staphylococcus aureus was lower. Of 67 strains of Enterobacteriaceae tested for an aminoglycoside, 6% were found to be resistant, whereas 8% of 48 Enterobacteriaceae strains were found to be cefotaxime resistant. Methicillin...

Multiple bacterial species reside in chronic wounds

DEFF Research Database (Denmark)

Gjødsbøl, Kristine; Christensen, Jens Jørgen; Karlsmark, Tonny

2006-01-01

species present were identified. More than one bacterial species were detected in all the ulcers. The most common bacteria found were Staphylococcus aureus (found in 93.5% of the ulcers), Enterococcus faecalis (71.7%), Pseudomonas aeruginosa (52.2%), coagulase-negative staphylococci (45.7%), Proteus...

Biofilm synthesis and its relationship with genetic characteristics in clinical methicillin-resistant staphylococci

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Nikolaos Giormezis

2015-09-01

Full Text Available Staphylococcus aureus can cause a broad range of infections, including skin infections, pneumonia and bacteraemia. Coagulase-negative staphylococci (CNS, mainly S. epidermidis, have also emerged as important pathogens, especially in immunocompromised patients or those with prosthetic devices, such as intravascular catheters or biomaterials. Of great importance in the initiation of these infections is the ability of staphylococci to adhere to various surfaces, such as host tissues and prosthetic devices and to form biofilm. The staphylococcal adhesins are encoded by a number of genes such as fnbA (S. aureus fibronectin binding protein A, sasG (S. aureus surface protein G, aap (S. epidermidis accumulation associated protein, bhp (Bap homologue protein and fbe (fibrinogen binding protein epidermidis. In this study, 106 methicillin-resistant S. aureus (MRSA, 145 methicillin-resistant S. epidermidis (MRSE and 70 non-epidermidis methicillin-resistant CNS (MR-CNS; 58 S. haemolyticus, 10 S. hominis and two S. lugdunensis were compared in terms of biofilm formation, antimicrobial resistance, clonal distribution and adhesin genes carriage. Isolates were classified into pulsotypes by PFGE and assigned to sequence types by MLST. In total, 121/321 isolates (37.7% produced biofilm and 219 (68.2% carried ica operon. The majority was multidrug resistant (94.7% and carried one or more adhesin genes. MRSE and all other MR-CNS prevailed in biofilm formation (P < 0.001 and antimicrobial resistance (P < 0.05 as compared to MRSA. MRSE also prevailed in ica carriage compared to the other methicillin-resistant staphylococci (P ≤ 0.007 Among MRSE, isolates from bacteraemias prevailed in biofilm formation (P = 0.031, whereas, strains from prosthetic device-associated infections carried more frequently aap (P = 0.003. Even though PFGE showed genetic diversity among MRSE, MLST revealed three major clones (ST2, ST5, ST16. MRSA isolates were less diverse, with five PFGE

Genotypes, antibiotic resistance, and virulence factors of staphylococci from ready-to-eat food.

Science.gov (United States)

Podkowik, Magdalena; Bystroń, Jarosław; Bania, Jacek

2012-01-01

Sixty-seven staphylococcal isolates belonging to 12 species were obtained from 70 ready-to-eat food products. Staphylococcus aureus (n=25), and Staphylococcus epidermidis (n=13) were dominant. Susceptibility to penicillin, oxacillin, tetracycline, clindamycin, gentamicin, erythromycin, ciprofloxacin, and vancomycin was determined. All investigated S. aureus isolates were resistant to at least one antibiotic, and fifteen isolates were resistant to four and more antibiotics. Thirty-eight coagulase-negative staphylococci (CNS) isolates were resistant to at least one antibiotic, and seventeen to four and more antibiotics. Fifteen CNS isolates were mecA positive, and grew in the presence of 6 μg/mL oxacillin. All S. aureus isolates were mecA-negative. Arginine catabolic mobile element (ACME) was found in seven S. epidermidis isolates. Five S. epidermidis isolates harbored ica operon, ACME and were able to form biofilm. Three of them also possessed IS256 element and were mecA-positive. The expression of icaA gene was comparable in five ica-positive S. epidermidis isolates. One of six mecA positive S. epidermidis isolates was classified as sequence type (ST)155, one as ST110, and two as ST88. Two methicillin-resistant Staphylococcus epidermis (MRSE) belonged to new STs, that is, ST362, and ST363. Enterotoxin genes were found in 92% of S. aureus isolates. No enterotoxin gene was detected in analyzed CNS population. We show that ready-to-eat products are an important source of antibiotic-resistant CNS and potentially virulent strains of S. epidermidis, including genotypes undistinguishable from hospital-adapted clones.

Conjunctival sac bacterial flora isolated prior to cataract surgery

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Suto C

2012-01-01

Full Text Available Chikako Suto1,2, Masahiro Morinaga1,2, Tomoko Yagi1,2, Chieko Tsuji3, Hiroshi Toshida41Department of Ophthalmology, Saiseikai Kurihashi Hospital, Saitama; 2Department of Ophthalmology, Tokyo Women's Medical University, Tokyo; 3Department of Clinical Laboratory, Saiseikai Kurihashi Hospital, Saitama; 4Department of Ophthalmology, Juntendo University Shizuoka Hospital, Izunokuni, Shizuoka, JapanObjective: To determine the trends of conjunctival sac bacterial flora isolated from patients prior to cataract surgery.Subjects and methods: The study comprised 579 patients (579 eyes who underwent cataract surgery. Specimens were collected by lightly rubbing the inferior palpebral conjunctival sac with a sterile cotton swab 2 weeks before surgery, and then cultured for isolation of bacteria and antimicrobial sensitivity testing. The bacterial isolates and percentage of drug-resistant isolates were compared among age groups and according to whether or not patients had diabetes mellitus, hyperlipidemia, dialysis therapy, oral steroid use, dry eye syndrome, or allergic conjunctivitis.Results: The bacterial isolation rate was 39.2%. There were 191 strains of Gram-positive cocci, accounting for the majority of all isolates (67.0%, among which methicillin-sensitive coagulase-negative staphylococci was the most frequent (127 strains, 44.5%, followed by methicillin-resistant coagulase-negative staphylococci (37 strains, 12.7%. All 76 Gram-positive bacillary isolates (26.7% were from the genus Corynebacterium. Among the 16 Gram-negative bacillary isolates (5.9%, the most frequent was Escherichia coli (1.0%. The bacterial isolation rate was higher in patients >60 years old, and was lower in patients with dry eye syndrome, patients under topical treatment for other ocular disorders, and patients with hyperlipidemia. There was no significant difference in bacterial isolation rate with respect to the presence/absence of diabetes mellitus, steroid therapy, dialysis, or

Caracterização fenotípica da resistência a antimicrobianos e detecção do gene mecA em Staphylococcus spp. coagulase-negativos isolados de amostras animais e humanas Phenotypic characterization of antimicrobial resistance and detection of the mecA gene in coagulase-negative Staphylococcus spp. isolates from animal and human samples

Directory of Open Access Journals (Sweden)

Lidiane de Castro Soares

2008-08-01

Full Text Available Os estafilococos coagulase-negativos (ECN fazem parte da microbiota normal da pele e, apesar de terem sido considerados saprófitas por muito tempo, o seu significado clínico como agente etiológico tem aumentado com o passar dos anos. Neste estudo, foram obtidos 72 isolados de ECN a partir de amostras do conduto auditivo de cães, de mastite bovina e de infecções humanas. Staphylococcus xylosus foi o microrganismo mais isolado, nas amostras animais, e S. cohnii subsp. cohnii em humanos. Os isolados foram avaliados de modo a traçar o perfil fenotípico de sua resistência aos antimicrobianos mais indicados no tratamento de infecções estafilocócicas. Foi detectado um elevado nível de resistência à penicilina e ampicilina. A gentamicina, a vancomicina e a associação ampicilina+sulbactam foram eficientes frente aos isolados testados. A resistência à oxacilina foi avaliada por meio dos testes de difusão em disco modificada, ágar screen, microdiluição em caldo e diluição em ágar para constatar, se à semelhança do que ocorre com os estafilococos coagulase-positivo, esta pode ser mediada pelo gene mecA e apresentada de forma heterogênea. A presença do gene mecA foi determinada pelo método da Reação em Cadeia de Polimerase (PCR, sendo 5,6% dos isolados mecA positivos.Coagulase-negative staphylococci (SCN make part of the normal microbiota skin and although they have been considered saprophytics for years, nowadays their clinical significance as an etiologic agent has increased. In this study, 72 SCN isolates obtained from external ear canals of dogs, bovine mastitis and human nosocomial infections were evaluated. Staphylococcus xylosus was the most prevalent microorganism in animal samples and S. cohnii subsp. cohnii in human samples. SCN isolates were evaluated in order to establish a phenotypical resistance pattern towards the most indicated antibiotics for staphyloccocal infections. A high level of resistance to penicillin

Prevalence and persistence of coagulase-negative Staphylococcus species in three dairy research herds.

Science.gov (United States)

Gillespie, B E; Headrick, S I; Boonyayatra, S; Oliver, S P

2009-02-16

Coagulase-negative Staphylococcus species (CNS) were isolated from 11.3% (1407 of 12,412) of mammary quarter milk samples obtained from cows in three dairy research herds in 2005. Approximately 27% (383/1407) of CNS was identified to the species level. The species distribution among those CNS identified from all herds was Staphylococcus chromogenes (48%), Staphylococcus hyicus (26%), Staphylococcus epidermidis (10%), Staphylococcus simulans (7%), Staphylococcus warneri (2%), Staphylococcus hominis (2%), Staphylococcus saprophyticus (1%), Staphylococcus xylosus (1%), Staphylococcus haemolyticus (Staphylococcus sciuri (Staphylococcus intermedius (<1%). Staphylococcuschromogenes was the predominant CNS isolated from all three herds; however, differences were seen in the prevalence of other CNS species. A total of 158 CNS (S. chromogenesn=66, S. hyicusn=38, S. epidermidisn=37, S. simulans n=10, and S. warneri n=7) were analyzed by pulsed-field gel electrophoresis (PFGE). The majority (33/41) of CNS isolated from the same mammary quarter on more than one occasion had the same PFGE pattern indicating persistence of the same infection over time. When all PFGE patterns for each CNS were analyzed, no common pulsotype was seen among the three herds indicating that CNS are quite diverse. Composite milk somatic cell count (SCC) data were obtained +/-14d of when CNS were isolated. Average milk SCC (5.32 log(10)/ml) for cows in which CNS was the only bacteria isolated was significantly higher than the average milk SCC (4.90 log(10)/ml) from cows with quarter milk samples that were bacteriologically negative.

Staphylococcus species and their Methicillin-Resistance in 7424 Blood Cultures for Suspected Bloodstream Infections

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Ariana ALMAŞ

2011-06-01

Full Text Available Objectives: The aim of this study was to evaluate the distribution of Staphylococcus species in bloodstream infections and to assess their susceptibility to methicillin. Material and Methods: Between January 1st 2008 - December 31st 2010, 7424 blood culture sets were submitted to the Laboratory Department of the Hospital for Clinical Infectious Diseases in Cluj-Napoca, Romania. The blood cultures were performed using BacT/Alert until January 2010 and BacT/Alert 3D automated system (bioMérieux after that date. The blood culture bottles were incubated at 37°C in a continuously monitoring system for up to 7 days. The strain identifications were performed by conventional methods, ApiStaph galleries and Vitek 2 Compact system. Susceptibility to methicillin was determined by disk diffusion method with cefoxitin disk and by using Vitek 2 Compact system. Results: From the total number of performed blood cultures, 568 were positive with Staphylococcus species. From 168 bacteriemic episodes 103 were with Staphylococcus aureus. Among 65 coagulase-negative staphylococci isolates, Staphylococcus epidermidis was the most frequently isolated species (34, followed by Staphylococcus hominis (15, Staphylococcus haemolyticus (8, Staphylococcus saprophyticus (3, Staphylococcus cohnii (1, Staphylococcus auricularis (1, and 3 strains that were not identified at species level. Methicillin resistance was encountered in 53.40% of Staphylococcus aureus strains and in 80% of coagulase-negative staphylococci. Conclusions: An important percentage of blood cultures were contaminated with Staphylococcus species. The main species identified in true bacteriemia cases were Staphylococcus aureus and Staphylococcus epidermidis. The percentage of methicillin-resistance, proved to be high not only for coagulase-negative staphylococci but also for Staphylococcus aureus.

Short communication: Identification of coagulase-negative staphylococcus species from goat milk with the API Staph identification test and with transfer RNA-intergenic spacer PCR combined with capillary electrophoresis.

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Koop, G; De Visscher, A; Collar, C A; Bacon, D A C; Maga, E A; Murray, J D; Supré, K; De Vliegher, S; Haesebrouck, F; Rowe, J D; Nielen, M; van Werven, T

2012-12-01

Coagulase-negative staphylococci (CNS) are the most commonly isolated bacteria from goat milk, but they have often been identified with phenotypic methods, which may have resulted in misclassification. The aims of this paper were to assess the amount of misclassification of a phenotypic test for identifying CNS species from goat milk compared with transfer RNA intergenic spacer PCR (tDNA-PCR) followed by capillary electrophoresis, and to apply the tDNA-PCR technique on different capillary electrophoresis equipment. Milk samples were collected from 416 does in 5 Californian dairy goat herds on 3 occasions during lactation. In total, 219 CNS isolates were identified at the species level with tDNA-PCR and subjected to the API 20 Staph identification test kit (API Staph; bioMérieux, Durham, NC). If the same species was isolated multiple times from the same udder gland, only the first isolate was used for further analyses, resulting in 115 unique CNS isolates. According to the tDNA-PCR test, the most prevalent CNS species were Staphylococcus epidermidis, Staphylococcus caprae, and Staphylococcus simulans. Typeability with API staph was low (72%). Although the API Staph test was capable of identifying the majority of Staph. epidermidis and Staph. caprae isolates, sensitivity for identification of Staph. simulans was low. The true positive fraction was high for the 3 most prevalent species. It was concluded that the overall performance of API Staph in differentiating CNS species from goat milk was moderate to low, mainly because of the low typeability, and that genotypic methods such as tDNA-PCR are preferred. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Trends of Bacterial Keratitis Culture Isolates in Jerusalem; a 13- Years Analysis.

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Michael Politis

Full Text Available To describe the trends in pathogens and antibacterial resistance of corneal culture isolates in infectious keratitis during a period of 13 years at Hadassah-Hebrew University Medical Center.A Retrospective analysis of bacterial corneal isolates was performed during the months of January 2002 to December 2014 at Hadassah Hebrew University Medical Center. Demographics, microbiological data and antibiotic resistance and sensitivity were collected.A total of 943 corneal isolates were analyzed during a 13 year period. A total of 415 positive bacterial cultures and 37 positive fungal cultures were recovered, representing 48% of the total cultures. The Annual incidence was 34.78 ± 6.54 cases. The most common isolate was coagulase-negative staphylococcus (32%, which had a significant decrease in trend throughout the study period (APC = -8.1, p = 0.002. Methicillin-resistant Staphylococcus aureus (MRSA appears to have a decrease trend (APC = -31.2, P = 0.5. There was an increase in the resistance trend of coagulase-negative staphylococci to penicillin (APC = 5.0, P = <0.001. None of the pathogens had developed any resistance to Vancomycin. (P = 0.88.Coagulase negative staphylococci were the predominant bacteria isolated from patients with keratitis. There was no significant change in the annual incidence of cases of bacterial keratitis seen over the past 13 years. Keratitis caused by MRSA appeared to decrease in contrast to the reported literature.

Aerobic bacteria cultured from the mouth of the American opossum (Didelphis virginiana) with reference to bacteria associated with bite infections.

OpenAIRE

Howell, J M; Dalsey, W C

1990-01-01

The American opossum inflicts bite injuries both when hunted for food and when accidentally provoked when handled in captivity. This study involved aerobically culturing organisms from the mouths of seven wild opossums (Didelphis virginiana). Isolates included streptococci, coagulase-positive and -negative staphylococci, Aeromonas spp., Citrobacter freundii, Eikenella corrodens, and Escherichia coli.

eap Gene as novel target for specific identification of Staphylococcus aureus.

Science.gov (United States)

Hussain, Muzaffar; von Eiff, Christof; Sinha, Bhanu; Joost, Insa; Herrmann, Mathias; Peters, Georg; Becker, Karsten

2008-02-01

The cell surface-associated extracellular adherence protein (Eap) mediates adherence of Staphylococcus aureus to host extracellular matrix components and inhibits inflammation, wound healing, and angiogenesis. A well-characterized collection of S. aureus and non-S. aureus staphylococcal isolates (n = 813) was tested for the presence of the Eap-encoding gene (eap) by PCR to investigate the use of the eap gene as a specific diagnostic tool for identification of S. aureus. Whereas all 597 S. aureus isolates were eap positive, this gene was not detectable in 216 non-S. aureus staphylococcal isolates comprising 47 different species and subspecies of coagulase-negative staphylococci and non-S. aureus coagulase-positive or coagulase-variable staphylococci. Furthermore, non-S. aureus isolates did not express Eap homologs, as verified on the transcriptional and protein levels. Based on these data, the sensitivity and specificity of the newly developed PCR targeting the eap gene were both 100%. Thus, the unique occurrence of Eap in S. aureus offers a promising tool particularly suitable for molecular diagnostics of this pathogen.

Species level identification of coagulase negative Staphylococcus spp. from buffalo using matrix-assisted laser desorption ionization-time of flight mass spectrometry and cydB real-time quantitative PCR.

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Pizauro, Lucas J L; de Almeida, Camila C; Soltes, Glenn A; Slavic, Durda; Rossi-Junior, Oswaldo D; de Ávila, Fernando A; Zafalon, Luiz F; MacInnes, Janet I

2017-05-01

Incorrect identification of Staphylococcus spp. can have serious clinical and zoonotic repercussions. Accordingly, the aim of this study was to determine if matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and/or cydB real- time quantitative PCR (qPCR) could be used to accurately identify coagulase negative Staphylococcus spp. (CoNS) obtained from buffalo milk and milking environment samples. Seventy-five of 84 CoNS isolates could be identified to the species level (score value >1.99) using MALDI-TOF MS. However, as determined by cytochrome d ubiquinol oxidase subunit II (cydB) qPCR and by 16S RNA and cydB gene sequencing, 10S. agnetis strains were wrongly identified as S. hyicus by MALDI-TOF MS. In addition, 9 isolates identified by MALDI-TOF only to the genus level (score values between 1.70 and 1.99) could be identified to species by cydB qPCR. Our findings suggest that MALDI-TOF MS is a reliable method for rapid identification of S. chromogenes and S. epidermidis (species of interest both in human and veterinary medicine) and may be able to correctly identify other Staphylococcus spp. However, at present not all Staphylococcus spp. found in buffalo milk can be accurately identified by MALDI-TOF MS and for these organisms, the cydB qPCR developed in the current study may provide a reliable alternative method for rapid identification of CoNS species. Copyright © 2017 Elsevier B.V. All rights reserved.

Etiologia das infecções intramamárias em vacas primíparas no período pós-parto Etiology of intramammary infections in primiparous cows at postparturition

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Paulo Eduardo Pardo

1998-07-01

Full Text Available Foram analisadas 664 amostras de leite de 83 vacas primíparas da raça Holandesa. As amostras foram colhidas no primeiro e no sétimo dia após o parto. Das 664 amostras analisadas, 488 (73,50% foram bacteriologicamente negativas e 176 (26,50%, positivas para microrganismos aeróbios. Foi observado um alto índice de mastite clínica (20,48%. Os agentes isolados com maior freqüência foram os Staphylococcus spp coagulase negativo (64,20%, Staphylococcus spp coagulase positivo (8,52%, Streptococcus spp (7,96%, Actinomyces pyogenes (4,55%, Mycoplasma bovigenitalium (3,40% e Escherichia coli (2,84%. Foi observado um maior índice de isolamento de patógenos no primeiro dia (17,62% em relação ao sétimo (8,88%.A total of 664 foremilk samples from 83 Holstein cows were cultured. Quarter samples were collected at parturition and 7 days post the first parturition. From 664 milk samples examined, 488 (73.50% were bacteriologically negative and 176 (26.50% were positive. A high incidence (20.48% of clinical mastitis was observed. The most frequently encountered isolates were coagulase negative staphylococci (64.20%, coagulase positive staphylococci (8.52%, streptococci (7.96%, Actinomyces pyogenes (4.55%, Mycoplasma bovigenitalium (3.40% and Escherichia coli (2.84%. The frequency of mastitis pathogen isolation was highest at parturition (17.62% and decreased markedly during the first week (8.88%.

Chronic alcoholism and microbial keratitis.

OpenAIRE

Ormerod, L. D.; Gomez, D. S.; Schanzlin, D. J.; Smith, R. E.

1988-01-01

In a series of 227 consecutive, non-referred patients with microbial keratitis an analysis of the accumulated hospital records showed that one-third were associated with chronic alcoholism. The diagnosis of alcoholism was usually unsuspected on admission to hospital. The microbial pathogenesis in these patients was distinctive; coagulase-negative staphylococci, alpha- and beta-streptococci, moraxellae, enteric Gram-negative bacilli, and polymicrobial infections were unusually prominent. Pseud...

Characterization of Staphylococcus aureus nasal colonization rates ...

African Journals Online (AJOL)

No resistance was detected to linezolid and vancomycin in all isolates. Coagulase negative staphylococci carriage was 87% in all our volunteers and was highest in the HCWs (93%). In conclusion, the study shows the need for a periodic screening of both the community and hospital personnel to adopt strategies for treating ...

Aerobic bacteria cultured from the mouth of the American opossum (Didelphis virginiana) with reference to bacteria associated with bite infections.

Science.gov (United States)

Howell, J M; Dalsey, W C

1990-01-01

The American opossum inflicts bite injuries both when hunted for food and when accidentally provoked when handled in captivity. This study involved aerobically culturing organisms from the mouths of seven wild opossums (Didelphis virginiana). Isolates included streptococci, coagulase-positive and -negative staphylococci, Aeromonas spp., Citrobacter freundii, Eikenella corrodens, and Escherichia coli. PMID:2229365

Bilateral Neck Pyomyositis Caused by Staphylococcus capitis and Staphylococcus saccharolyticus in a Diabetic Adult

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Nicholas Young

2017-01-01

Full Text Available We report a case of pyomyositis of the paraspinal neck muscles caused by two coagulase-negative staphylococci: Staphylococcus capitis and Staphylococcus saccharolyticus. Inflammation in the spermatic cords was an additional feature of this infection. Treatment with six weeks of first-generation cephalosporin therapy resulted in complete clinical and radiological resolution.

Carriage of Staphylococcus species in the veterinary visiting dog population in mainland UK: molecular characterisation of resistance and virulence.

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Wedley, Amy L; Dawson, Susan; Maddox, Thomas W; Coyne, Karen P; Pinchbeck, Gina L; Clegg, Peter; Jamrozy, Dorota; Fielder, Mark D; Donovan, David; Nuttall, Tim; Williams, Nicola J

2014-05-14

This study investigated the prevalence of nasal carriage of staphylococci in dogs and determined the characteristics of the isolates. A total of 724 dogs from 87 veterinary practices across the mainland UK were screened for carriage of Staphylococcus spp. All isolates were examined for meticillin resistance (MR) and the presence of the mecA gene investigated in those isolates showing resistance. All coagulase-positive staphylococci and MR coagulase-negative staphylococci (MRCoNS) were subjected to antimicrobial susceptibility testing. Spa typing and DNA microarray analysis of resistance and virulence genes was carried out on all MR S. aureus (MRSA) and a subset of meticillin susceptible S. aureus (MSSA). Staphylococci were isolated from 399 (55.1%) of the dogs; only seven (1%) carried MRSA, all of which were identified as the dominant UK healthcare-associated strain (EMRSA-15, ST22). MSSA was identified in 47 (6.5%) dogs, the sequence types of which have been suggested as precursors to successful MRSA clones. Forty (5.5%) dogs carried MRCoNS, while no dogs carried MR S. pseudintermedius, although this is increasingly reported in mainland Europe. Resistance to antimicrobials among the isolates varied between species, with multidrug resistance (MDR) in 87.5% of MRCoNS and 21.8% of coagulase positive staphylococci. Microarray analysis of MRSA and a subset of MSSA isolates identified numerous virulence genes associated with pathogenesis, which are commonly identified in isolates of human origin. However, no isolates carried Panton-Valentine leukocidin (PVL) genes. This study suggests that MRSA carriage is low in the vet visiting dog population, but there is a diverse range of virulence and resistance determinants in canine S. aureus and MRCoNS isolates. Copyright © 2014 Elsevier B.V. All rights reserved.

Worldwide Endemicity of a Multidrug-Resistant Staphylococcus capitis Clone Involved in Neonatal Sepsis.

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Butin, Marine; Martins-Simões, Patricia; Rasigade, Jean-Philippe; Picaud, Jean-Charles; Laurent, Frédéric

2017-03-01

A multidrug-resistant Staphylococcus capitis clone, NRCS-A, has been isolated from neonatal intensive care units in 17 countries throughout the world. S. capitis NRCS-A prevalence is high in some neonatal intensive care units in France. These data highlight the worldwide endemicity and epidemiologic relevance of this multidrug-resistant, coagulase-negative staphylococci clone.

[Bacteremia and sepsis in patients hospitalized at the Dr. Fran Mihaljevíc Clinic for Infectious Diseases in Zagreb 1987-1991].

Science.gov (United States)

Skerk, V; Schönwald, S; Bobinac, E; Bejuk, D; Zrinsćak, J

1995-01-01

A total number of 836 episodes of bacteremia and fungemia were examined in 823 hospitalized patients in the University Hospital of Infectious Diseases "Dr Fran Mihaljević" Zagreb from the beginning of 1987 to the end of 1991. Twenty-five percent of them were nosocomial bacteremias and 5% were polymicrobial bacteremias. The most frequently isolated causative agents were Salmonella spp. (26%), Escherichia coli (17%), Streptococcus pneumoniae (11%) and Staphylococcus aureus (8%). There were 34% of gram-positive bacteremias. The increased frequency of nosocomial bacteremias caused by coagulase-negative staphylococci was recorded. The frequency of coagulase-negative staphylococci strains resistant to gentamicin and Klebsiella spp. strains resistant to cefotaxime was increased. Shock was present in 19% of episodes. Relation between septic shock occurrence and causative agent of bacteremia was not proved. Mortality in patients with bacteremia was 13%, and total mortality was 20%. The outcome of the disease was in direct relation with causative agent of bacteremia. The initial empiric antimicrobial therapy was prolonged in 91% of episodes of bacteremia after blood culture results were known.

Trends in udder health and emerging mastitogenic pathogens in South African dairy herds

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I.M. Petzer

2009-05-01

Full Text Available The aim of this study was to retrospectively analyse the results of milk samples obtained from South African dairy herds during the period 1996 to April 2007 in order to identify possible trends in isolates of microorganisms and their pathogenicity under field conditions. Milk samples were obtained from 7 of the 9 provinces in South Africa where there are low numbers of dairy cows. Although there is scientific limitation to a country wide survey, such as the variation in herd size, management skills, parity, milk yield, milking frequency and other parameters, the size of this database helps to give a fair indication of general udder health in South Africa. Cytology and routine bacteriology were performed on 379 000 milk samples of lactating cows and bacteriology on 11 946 samples from non-lactating cows. According to the results obtained, mastitis did not decrease in South Africa over the test period. The prevalence of mastitis and teat canal infection was lowest in 2002. Mastitis and teat canal infection increased from 2002 to 2006 from 8.1 % and 24.1 % to 15.4 and 30.0 % respectively. The percentage of mastitogenic pathogens isolated from cows over these years also varied. Previously unknown or almost eradicated mastitogenic pathogens such as αβ haemolytic Staphylococcus aureus which is thought to be of human origin, Streptococcus agalactiae and Enterococcus canis were responsible for numerous mastitis outbreaks seen in the test samples. Coagulase-negative staphylococci were the most frequently isolated bacteria in milk samples from both lactating and dry cows, followed by Staphylococcus aureus and Streptococcus agalactiae. Although Staphylococcus aureus remained the principal mastitogenic pathogen in South Africa, owing to its chronic nature and resultant economic losses, most cases of mastitis were caused by coagulase-negative staphylococci. This finding increases the importance of coagulase-negative staphylococci (formerly described as a

Browse Title Index

African Journals Online (AJOL)

Items 301 - 350 of 458 ... F.C. Thomas, O.S. Aduloju, B Okediran, E.S. Ajibola, E.N. Maduagwu. Vol 37, No 3 (2016), Prevalence and antimicrobial resistance pattern of coagulase negative Staphylococci isolated from pigs and in-contact humans in Jos Metropolis, Nigeria, Abstract PDF. A.H. Momoh, J. K. P. Kwaga, M. Bello, ...

Investigate Nasal Colonize Staphylococcus Species Biofilm Produced

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Cemil Demir

2014-03-01

Full Text Available Aim: 127 S.aureus and 65 CoNS strains were isolated from patients noses%u2019. To produce a biofilm ability was investigated using three different methods. Slime-positive and negative staphylococcies%u2019 resistance were evaluated against different antibiotics. Material and Method: Swap samples puted 7% blood agar. Staphylococcus aureus and coagulase-negative staphylococci (CoNS isolates biofilm produced ability were investigated using Congo Red Agar (CRA, microplates (MP and Standard Tube (ST methods. In addition to that, presence of antibiotic resistance of the staphylococcal isolates are determined agar disc diffusion method. Results: The rate of biofilm producing Staphylococcus spp strains was found to be 72.4%, 67.7%, and 62.9%, respectively with CRA, MP, and ST tests. There was no significant relationship among the tests (p>0.05. In addition, antibiotic resistance of Staphylococcus spp. against various antibiotics was also determined by the agar disk diffusion method. Resistance rates of biofilm positive (BP Staphylococcus spp for penicilin G, ampicilin, amocycilin/clavulanic acid, tetracyclin, eritromycin, gentamycin, and enrofloxacin 71.7%, 69.7%, 6.2%, 20.7%, 21.4%, 1.4%, and 0.7%, respectively. Resistance rates of biofilm negative (BN spp for 42.6%, 23.4%, 4.3%, 14.9%, 19.1%, 0.0%, 0.0% respectively. All Staphylococcus isolates were found to be susceptible to vancomycin and teicaplonin. Although BP strains antibiotic resistance rates were observed higher than BN strains. But resistance rates were not found statistically significant (p>0.05. Discussion: CRA is the reliablity and specifity method to determine Staphylococcus spp. biofilm produce ability.

Microbiological diagnosis in revision of infected knee arthroplasties in Denmark

DEFF Research Database (Denmark)

Lindberg-Larsen, Martin; Pitter, Frederik Taylor; Voldstedlund, Marianne

2017-01-01

. METHODS: One hundred and two partial revisions (open debridement and exchange of tibial insert) and 213 two-stage procedures performed due to infection in 275 patients from 1 July 2011 to 30 June 2013 were included and analysed by linkage to data from a nationwide registry on microbiological test results....... RESULTS: 78 (24.8%) revisions were culture negative, 192 (60.9%) showed monomicrobial growth and 43 (14.3%) polymicrobial growth. Staphylococcus aureus was the most frequent isolate in mono-culture in 70 (22.2%) revisions and in polymicrobial culture in 15 revisions with a total frequency of 27.0%. Only...... one case (1.4%) of methicillin-resistance was registered. Coagulase-negative staphylococci (CoNS) were frequent, sole pathogen in 65 revisions and in polymicrobial cultures in 28 revisions with a total frequency of 29.5%. A pre-operative knee aspiration was performed in 50% and preoperative blood...

Bacteriological quality of raw human milk: effect of storage in a refrigerator.

Science.gov (United States)

Olowe, S A; Ahmed, I; Lawal, S F; Ransome-Kuti, S

1987-12-01

Eighty-seven breast milk samples were obtained from 63 mothers of infants on the neonatal intensive care unit of the Lagos University Teaching Hospital. The samples were cultured for bacteria immediately after collection (0 h) and then stored in a domestic refrigerator from where cultures were repeated at 6-hourly intervals for 24 h. At 0 h, three (3.4%) of the samples were sterile; 56 (64%) grew coagulase negative staphylococci, and one (1.1%) Streptococcus viridans. Thus, 60 (69%) of the samples were either sterile or contained only skin commensals. Twenty-nine (31%) grew potential pathogens--coagulase positive staphylococci in two (2.3%) and mixed growth of staphylococci, coliforms and klebsiella in 25 (28.3%). During the 24 h storage in the refrigerator, bacteria multiplied in 50 and their growth was inhibited in 32 of the samples. But the mean bacterial count at any time during the 24 h was not significantly different from that at the beginning of the storage in the refrigerator. It is proposed that expressed breast milk stored in a domestic refrigerator can be given safely to infants within 24 h of collection if heavy contamination is prevented at the time of collection.

The typing of Staphylococcus epidermidis by a lectin-binding assay

DEFF Research Database (Denmark)

Jarløv, J O; Hansen, J E; Rosdahl, V T

1992-01-01

A new typing method for Staphylococcus epidermidis was developed. Four biotinylated lectins--wheat germ agglutinin (WGA), soy bean agglutinin (SBA), lentil agglutinin (LCA) and Concanavalin A (ConA)--were added to immobilised whole cells of coagulase-negative staphylococci (CNS) in microtitration...... plates. The amount of bound lectin was measured by peroxidase-conjugated avidin followed by a peroxidase reaction. The method was compared to antibiotic-resistance analysis, phage typing, plasmid DNA profiles and slime production. A total of 113 isolates of CNS from 21 patients was investigated and 71...... strains of CNS, including 64 strains of S. epidermidis, were detected if all typing methods were taken into consideration. If only one typing method was used the highest discriminatory power among the S. epidermidis isolates was obtained with the lectin-binding assay which allowed 49 different strains...

Enterotoxigenic coagulase positive Staphylococcus in milk and milk products, lben and jben, in northern Morocco.

Science.gov (United States)

Bendahou, Abdrezzak; Abid, Mohammed; Bouteldoun, Nadine; Catelejine, Dierick; Lebbadi, Mariam

2009-04-30

The aim of this research was to determine the prevalence of enterotoxin genes (sea-seo) in Coagulase Positive Staphylococcus (CPS) isolated from unpasteurized milk and milk products. These results were compared with the results obtained by using the detection kit SET-RPLA for the specific detection of staphylococcal enterotoxins (SEA-SED). Eighty-one samples of milk and milk products were analyzed for the presence of Staphylococcus strains. Forty-six coagulase positive Staphylococcus isolates were tested for the production of staphylococcal enterotoxins (SEA-SED) by using the reversed passive latex agglutination method. The strains were also tested for the presence of se genes (sea-seo) by polymerase chain reaction. One or more classical enterotoxin products (SEA-SED) were observed in 39% of the strains tested, while se genes were detected in 56.5%. SEA and sea were most commonly detected. For newly discovered se genes among CPS isolates tested in this study, except the seh gene which was revealed in four isolates (8.7 %), none of the strains harbored any of the other se genes (see, seg, sei, sej, sek, sel, sem, seo and sen). The finding of a pathogen such as staphylococci-producing SEs and containing se genes in milk and milk products in northern Morocco may indicate a problem for public health in this region. The presence of enterotoxigenic strains in food does not always necessarily mean that the toxin will be produced. For that reason, the combination of both methods (RPLA and PCR) is a guarantee for success in diagnostic analysis tests.

Long-term epidemiology of bacterial susceptibility profiles in adults suffering from febrile neutropenia with hematologic malignancy after antibiotic change

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J Mebis

2010-07-01

Full Text Available J Mebis1,2, H Jansens3, G Minalu4, G Molenberghs4, WA Schroyens1, AP Gadisseur1, A van de Velde1, I Vrelust1, H Goossens3, ZN Berneman11Division of Hematology, Antwerp University Hospital, Edegem, 2Division of Medical Oncology, Jessa Hospital, Hasselt, 3Division of Microbiology, Antwerp University Hospital, Edegem, 4Interuniversity Institute for Biostatistics and Statistical Bioinformatics, Hasselt University, Hasselt, BelgiumObjective: The aim of this study was to investigate the epidemiology and antibiotic ­susceptibility profiles of isolated bacterial organisms in relation to empiric treatment of neutropenic fever over a 15-year period.Methods: All patients with or at risk febrile neutropenia and treated in the hematology ward of the Antwerp University Hospital during 1994–2008 were prospectively included. Skin, blood, and urine cultures were taken. Oral quinolone prophylaxis was started in patients with neutropenia without fever. Empiric starting therapy consisted of amikacin in combination with cefepime.Results: A total of 3624 bacteria were isolated. The most common pathogens were coagulase-negative Staphylococci (46%, followed by Escherichia coli (25%, Enterobacteriaceae (15.6%, Staphylococcus aureus (7.2%, and Pseudomonas aeruginosa (3.8%. The balance between Gram-positive and Gram-negative bacteria remained stable, with a majority of Gram-positive bacteria. A shift from oxacillin-sensitive to oxacillin-resistant coagulase-negative Staphylococci was observed. Regarding susceptibility patterns, no vancomycin resistance was detected in coagulase-negative Staphylococci or in S. aureus. The E. coli susceptibility rates remained stable. However, 66% of bloodstream infections were ciprofloxacin-resistant. A reduced susceptibility of P. aeruginosa strains to meropenem was noticed.Conclusions: Improvement in antibiotic susceptibility of inducible Enterobacteriaceae ­following a switch of empiric antibiotic therapy was maintained 15 years

Genetic regulation of the intercellular adhesion locus in staphylococci

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David R Cue

2012-03-01

Full Text Available The formation of biofilms by Staphylococcus aureus and Staphylococcus epidermidis is an important aspect of many staphylococcal infections, most notably endocarditis, osteomyelitis and infections associated with indwelling medical devices. The major constituents of S. aureus biofilms are polysaccharides, such as poly N-acetyl glucosamine (PIA/PNAG, cell surface and secreted bacterial proteins, and extracellular DNA. The exact composition of biofilms often varies considerably between different strains of staphylococci and between different sites of infection by the same strain. PIA/PNAG is synthesized by the products of 4 genes, icaADBC, that are encoded in a single operon. A fifth gene, icaR, is a negative regulator of icaADBC. Expression of icaADBC is tightly regulated, but can often be induced in vitro by growing staphylococci in the presence of high salt, high glucose or ethanol. Regulation of icaADBC is complex and numerous regulatory factors have been implicated in control of icaADBC. Many of these are well known global transcriptional regulatory factors like SarA and sigmaB, whereas other regulators, such as IcaR, seem to affect expression of relatively few genes. Here, we will attempt to summarize how various regulatory factors affect the production of PIA/PNAG in staphylococci.

[Investigation of biofilm formation properties of staphylococcus isolates].

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Öcal, Duygu Nilüfer; Dolapçı, İştar; Karahan, Zeynep Ceren; Tekeli, Alper

2017-01-01

Biofilm production is an important virulence factor which allows staphylococci to adhere to medical devices. The principal component of biofilm is a "polysaccharide intercellular adhesin (PIA)" which is composed of a beta-1,6-N-acetylglucosamine polymer synthesized by an enzyme (N-acetylglucosamine transferase) encoded by the ica operon found on the bacterial chromosome. This operon is composed of four genes (A, B, C, and D), and a transposable element IS256. In this study, we aimed to determine the biofilm production characteristics of invasive/non-invasive staphylococcus isolates and different staphylococcus species. Biofilm production of 166 staphylococci was phenotypically investigated on Congo Red Agar (CRA); the presence of icaA, icaD and IS256 genes were investigated by polymerase chain reaction (PCR). 74 of the isolates (44.6%) were identified as methicillin resistant Staphylococcus aureus (MRSA), 25 (15.1%) as methicillin sensitive S.aureus (MSSA), 25 (37.3%) as Staphylococcus hominis, 20 (12%) as S.epidermidis, ten (15%) as Staphylococcus haemolyticus, nine (13.4%) as Staphylococcus capitis, two (3%) Staphylococcus saprophyticus and one (1.5%) as Staphylococcus warnerii. Of the MRSA strains, 52 were isolated from blood and 22 from nose; all MSSA strains were isolated from nose cultures. Coagulase-negative staphylococci (CoNS) strains were composed of invasive and non-invasive strains isolated from nose, catheter tip and blood cultures from patients with catheter. Production with CRA method was found to be statistically significant in invasive isolates (paureus isolates produced biofilm on CRA (paureus when compared with CoNS. Carriage of three genes and biofilm formation capacity of invasive isolates can cause refractory infections and the importance of carriage and hospital infections of these bacteria, it is important to prevent the spread of these isolates. A combination of phenotypic and genotypic tests is recommended for the investigation of biofilm

Opportunistic microorganisms in patients undergoing antibiotic therapy for pulmonary tuberculosis

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Silvia Maria Rodrigues Querido

2011-12-01

Full Text Available Antimicrobial therapy may cause changes in the resident oral microbiota, with the increase of opportunistic pathogens. The aim of this study was to compare the prevalence of Candida, Staphylococcus, Pseudomonas and Enterobacteriaceae in the oral cavity of fifty patients undergoing antibiotic therapy for pulmonary tuberculosis and systemically healthy controls. Oral rinsing and subgingival samples were obtained, plated in Sabouraud dextrose agar with chloramphenicol, mannitol agar and MacConkey agar, and incubated for 48 h at 37ºC. Candida spp. and coagulase-positive staphylococci were identified by phenotypic tests, C. dubliniensis, by multiplex PCR, and coagulase-negative staphylococci, Enterobacteriaceae and Pseudomonas spp., by the API systems. The number of Candida spp. was significantly higher in tuberculosis patients, and C. albicans was the most prevalent specie. No significant differences in the prevalence of other microorganisms were observed. In conclusion, the antimicrobial therapy for pulmonary tuberculosis induced significant increase only in the amounts of Candida spp.

Phenol-Soluble Modulin Toxins of Staphylococcus haemolyticus

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Fei Da

2017-05-01

Full Text Available Coagulase-negative staphylococci (CoNS are important nosocomial pathogens and the leading cause of sepsis. The second most frequently implicated species, after Staphylococcus epidermidis, is Staphylococcus haemolyticus. However, we have a significant lack of knowledge about what causes virulence of S. haemolyticus, as virulence factors of this pathogen have remained virtually unexplored. In contrast to the aggressive pathogen Staphylococcus aureus, toxin production has traditionally not been associated with CoNS. Recent findings have suggested that phenol-soluble modulins (PSMs, amphipathic peptide toxins with broad cytolytic activity, are widespread in staphylococci, but there has been no systematic assessment of PSM production in CoNS other than S. epidermidis. Here, we identified, purified, and characterized PSMs of S. haemolyticus. We found three PSMs of the β-type, which correspond to peptides that before were described to have anti-gonococcal activity. We also detected an α-type PSM that has not previously been described. Furthermore, we confirmed that S. haemolyticus does not produce a δ-toxin, as results from genome sequencing had indicated. All four S. haemolyticus PSMs had strong pro-inflammatory activity, promoting neutrophil chemotaxis. Notably, we identified in particular the novel α-type PSM, S. haemolyticus PSMα, as a potent hemolysin and leukocidin. For the first time, our study describes toxins of this important staphylococcal pathogen with the potential to have a significant impact on virulence during blood infection and sepsis.

Characterization of mannitol-fermenting methicillin-resistant staphylococci isolated from pigs in Nigeria

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Clifford C. Ugwu

2015-09-01

Full Text Available This study was conducted to determine the species distribution, antimicrobial resistance pheno- and genotypes and virulence traits of mannitol-positive methicillin-resistant staphylococci (MRS isolated from pigs in Nsukka agricultural zone, Nigeria. Twenty mannitol-positive methicillin-resistant coagulase-negative staphylococcal (MRCoNS strains harboring the mecA gene were detected among the 64 Staphylococcus isolates from 291 pigs. A total of 4 species were identified among the MRCoNS isolates, namely, Staphylococcus sciuri (10 strains, Staphylococcus lentus (6 strains, Staphylococcus cohnii (3 strains and Staphylococcus haemolyticus (one strain. All MRCoNS isolates were multidrug-resistant. In addition to β-lactams, the strains were resistant to fusidic acid (85%, tetracycline (75%, streptomycin (65%, ciprofloxacin (65%, and trimethoprim/sulphamethoxazole (60%. In addition to the mecA and blaZ genes, other antimicrobial resistance genes detected were tet(K, tet(M, tet(L, erm(B, erm(C, aacA-aphD, aphA3, str, dfrK, dfrG, catpC221, and catpC223. Thirteen isolates were found to be ciprofloxacin-resistant, and all harbored a Ser84Leu mutation within the QRDR of the GyrA protein, with 3 isolates showing 2 extra substitutions, Ser98Ile and Arg100Lys (one strain and Glu88Asp and Asp96Thr (2 strains. A phylogenetic tree of the QRDR nucleotide sequences in the gyrA gene revealed a high nucleotide diversity, with several major clusters not associated with the bacterial species. Our study highlights the possibility of transfer of mecA and other antimicrobial resistance genes from MRCoNS to pathogenic bacteria, which is a serious public health and veterinary concern.

Characterization of mannitol-fermenting methicillin-resistant staphylococci isolated from pigs in Nigeria.

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Ugwu, Clifford C; Gomez-Sanz, Elena; Agbo, Ifeoma C; Torres, Carmen; Chah, Kennedy F

2015-01-01

This study was conducted to determine the species distribution, antimicrobial resistance pheno- and genotypes and virulence traits of mannitol-positive methicillin-resistant staphylococci (MRS) isolated from pigs in Nsukka agricultural zone, Nigeria. Twenty mannitol-positive methicillin-resistant coagulase-negative staphylococcal (MRCoNS) strains harboring the mecA gene were detected among the 64 Staphylococcus isolates from 291 pigs. A total of 4 species were identified among the MRCoNS isolates, namely, Staphylococcus sciuri (10 strains), Staphylococcus lentus (6 strains), Staphylococcus cohnii (3 strains) and Staphylococcus haemolyticus (one strain). All MRCoNS isolates were multidrug-resistant. In addition to β-lactams, the strains were resistant to fusidic acid (85%), tetracycline (75%), streptomycin (65%), ciprofloxacin (65%), and trimethoprim/sulphamethoxazole (60%). In addition to the mecA and blaZ genes, other antimicrobial resistance genes detected were tet(K), tet(M), tet(L), erm(B), erm(C), aacA-aphD, aphA3, str, dfrK, dfrG, cat pC221, and cat pC223. Thirteen isolates were found to be ciprofloxacin-resistant, and all harbored a Ser84Leu mutation within the QRDR of the GyrA protein, with 3 isolates showing 2 extra substitutions, Ser98Ile and Arg100Lys (one strain) and Glu88Asp and Asp96Thr (2 strains). A phylogenetic tree of the QRDR nucleotide sequences in the gyrA gene revealed a high nucleotide diversity, with several major clusters not associated with the bacterial species. Our study highlights the possibility of transfer of mecA and other antimicrobial resistance genes from MRCoNS to pathogenic bacteria, which is a serious public health and veterinary concern.

Identification of a novel vga(E) gene variant that confers resistance to pleuromutilins, lincosamides and streptogramin A antibiotics in staphylococci of porcine origin.

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Li, Jun; Li, Beibei; Wendlandt, Sarah; Schwarz, Stefan; Wang, Yang; Wu, Congming; Ma, Zhiyong; Shen, Jianzhong

2014-04-01

To investigate the genetic basis of pleuromutilin resistance in coagulase-negative staphylococci of porcine origin that do not carry known pleuromutilin resistance genes and to determine the localization and genetic environment of the identified resistance gene. Plasmid DNA of two pleuromutilin-resistant Staphylococcus cohnii and Staphylococcus simulans isolates was transformed into Staphylococcus aureus RN4220. The identified resistance plasmids were sequenced completely. The candidate gene for pleuromutilin resistance was cloned into shuttle vector pAM401. S. aureus RN4220 transformants carrying this recombinant shuttle vector were tested for their MICs. S. cohnii isolate SA-7 and S. simulans isolate SSI1 carried the same plasmid of 5584 bp, designated pSA-7. A variant of the vga(E) gene was detected, which encodes a 524 amino acid ATP-binding cassette protein. The variant gene shared 85.7% nucleotide sequence identity and the variant protein 85.3% amino acid sequence identity with the original vga(E) gene and Vga(E) protein, respectively. The Vga(E) variant conferred cross-resistance to pleuromutilins, lincosamides and streptogramin A antibiotics. Plasmid pSA-7 showed an organization similar to that of the apmA-carrying plasmid pKKS49 from methicillin-resistant S. aureus and the dfrK-carrying plasmid pKKS966 from Staphylococcus hyicus. Sequence comparisons suggested that recombination events may have played a role in the acquisition of this vga(E) variant. A novel vga(E) gene variant was identified, which was located on a small plasmid and was not associated with the transposon Tn6133 [in contrast to the original vga(E) gene]. The plasmid location may enable its further dissemination to other staphylococci and possibly also to other bacteria.

Subclinical mastitis in sheep: Causes and their sensitivity to antibiotics

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Vakanjac Slobodanka

2010-01-01

Full Text Available The California mastitis test (CMT was used to examine the milk of 6609 sheep, actually, from 13218 mammary complexes. A total of 986 milk samples were found to contain an increased number of somatic cells, and causes of mastitis were isolated from 910 (92.3% of these samples. The most frequently isolated microorganisms were: E. coli isolated from 189 (20.76% samples, Micrococcus sp from 186 (20.43% samples, Bacillus sp. from 177 (19.45%, Staphylococcus aureus from 172 (18.9% samples, and Proteus sp. from 121 (13.29% samples of sheep milk. Coagulase-negative staphylococci (CNS were isolated in a much smaller number, from 25 (2.74% samples, Streptococcus sp. was isolated from 19 (2.08% samples, Pseudomonas sp. from 14 (1.53% samples, haemolytic E. coli was isolated from only 6 (0.65% samples, and Streptococcus agalactiae from only one sample. Among the 25 isolates of coagulase-negative staphylococci, 16 (64% isolates were identified as Staphylococcus chromogenes, and 9 (36% isolates as Staphylococcus simulans. The sensitivity of the isolated causes of mastitis to antibiotics was examined using the disc diffusion method. .

Staphylococcus agnetis sp. nov., a coagulase-variable species from bovine subclinical and mild clinical mastitis.

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Taponen, Suvi; Supré, Karlien; Piessens, Veerle; Van Coillie, Els; De Vliegher, Sarne; Koort, Joanna M K

2012-01-01

Thirteen Gram-positive-staining coagulase-variable staphylococci were isolated from subclinical and mild clinical mastitic bovine milk (n=12) and a teat apex (n=1). The results of sequence analysis of the 16S rRNA gene and two housekeeping genes, rpoB and tuf, and DNA fingerprinting with amplified fragment length polymorphism (AFLP) analysis showed that the isolates formed a separate branch within the genus Staphylococcus. The phylogenetically most closely related species were Staphylococcus hyicus and Staphylococcus chromogenes. DNA-DNA hybridization with S. hyicus DSM 20459(T) and S. chromogenes DSM 20674(T) confirmed that the isolates belonged to a separate species. The predominant fatty acids were i-C(15:0), ai-C(15:0), i-C(17:0) and C(20:0) and the peptidoglycan type was A3α L-Lys-Gly(5). Based on the results of genotypic and phenotypic analyses, it is proposed that the thirteen isolates represent a novel species, for which the name Staphylococcus agnetis sp. nov. is proposed. Strain 6-4(T) (=DSM 23656(T)=CCUG 59809(T)) is the type strain.

Antistaphylococcal activity of LBM415, a new peptide deformylase inhibitor, compared with those of other agents.

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Credito, Kim; Lin, Gengrong; Ednie, Lois M; Appelbaum, Peter C

2004-10-01

The MICs of LBM415, a new peptide diformylase inhibitor, were coagulase-negative staphylococci. LBM415 MICs were similar irrespective of whether the strains were methicillin susceptible or resistant. All strains were also susceptible to vancomycin, linezolid, ranbezolid, daptomycin, oritavancin, and quinupristin-dalfopristin. LBM415 at the MIC was bacteriostatic after 24 h.

Community-acquired meningitis due to Staphylococcus capitis in the absence of neurologic trauma, surgery, or implants.

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Oud, Lavi

2011-01-01

Community-acquired meningitis due to coagulase-negative staphylococci in adults has been rarely reported and generally develops in patients with ventricular shunts or after neurosurgery or neurotrauma. Staphylococcus capitis is a rare cause of adult meningitis. We describe a patient with community-acquired meningitis due to S. capitis, in the absence of traditional risk factors, with atypical presentation. Copyright © 2011 Elsevier Inc. All rights reserved.

Coagulase-negative Staphylococcus species in bulk milk: Prevalence, distribution, and associated subgroup- and species-specific risk factors.

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De Visscher, A; Piepers, S; Haesebrouck, F; Supré, K; De Vliegher, S

2017-01-01

Coagulase-negative staphylococci (CNS) have become the main pathogens causing bovine mastitis in recent years. A huge variation in species distribution among herds has been observed in several studies, emphasizing the need to identify subgroup- and species-specific herd-level factors to improve our understanding of the differences in ecological and epidemiological nature between species. The use of bulk milk samples enables the inclusion of a large(r) number of herds needed to identify herd-level risk factors and increases the likelihood of recovering enough isolates per species needed for conducting subgroup- and, eventually, species-specific analyses at the same time. This study aimed to describe the prevalence and distribution of CNS species in bulk milk samples and to identify associated subgroup- and species-specific herd-level factors. Ninety percent of all bulk milk samples yielded CNS. Staphylococcus equorum was the predominant species, followed by Staphylococcus haemolyticus and Staphylococcus epidermidis. A seasonal effect was observed for several CNS species. Bulk milk samples from herds with a loose-pack or a tiestall housing system were more likely to yield CNS species compared with herds with a freestall barn, except for S. epidermidis, Staphylococcus simulans, and Staphylococcus cohnii. In September, herds in which udders were clipped had lower odds of yielding Staphylococcus chromogenes, S. simulans, and Staphylococcus xylosus, the CNS species assumed to be most relevant for udder health, in their bulk milk than herds in which udder clipping was not practiced. Bulk milk of herds participating in a monthly veterinary udder health-monitoring program was more likely to yield these 3 CNS species. Herds always receiving their milk quality premium or predisinfecting teats before attachment of the milking cluster had lower odds of having S. equorum in their bulk milk. Herds not using a single dry cotton or paper towel for each cow during premilking udder

Antimicrobial susceptibility of coagulase-negative Staphylococcus species isolated from bovine milk.

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Sawant, A A; Gillespie, B E; Oliver, S P

2009-02-16

Coagulase-negative Staphylococcus (CNS) isolates (n=168) obtained from milk from heifers and dairy cows were screened for minimum inhibitory concentration (MIC) to antimicrobials used commonly for mastitis therapy. Of the 10 CNS species included in the study, the predominant species were Staphylococcus chromogenes (n=61), Staphylococcus epidermidis (n=37), Staphylococcus hyicus (n=37), and Staphylococcus simulans (n=16). The majority of CNS was susceptible to ampicillin, oxacillin, cephalothin, and ceftiofur. Erythromycin and pirlimycin were also very effective in vitro inhibitors of CNS. The only exception was observed with S. epidermidis. Of 37 S. epidermidis evaluated, 13 (35%) exhibited efflux-based resistance to erythromycin (> or =16 microg/ml) encoded by msrA and one isolate carried ermC encoding ribosomal methylase-based resistance to both erythromycin (> or =64 microg/ml) and pirlimycin (> or =64 microg/ml). A total of 17 S. epidermidis, 11 S. chromogenes, and one S. hyicus exhibited phenotypic resistance to ampicillin (> or =0.5 microg/ml). Constitutive beta-lactamase production was observed in all ampicillin resistant isolates except 4 S. epidermidis that exhibited inducible beta-lactamase production. Induced beta-lactamase production was also observed in 13 S. epidermidis that were phenotypically susceptible to the entire MIC panel. All isolates that produced beta-lactamase either constitutively or by induction carried blaZ. S. epidermidis (n=12, 32%) that were resistant to methicillin (oxacillin > or =0.5 microg/ml) carried low affinity penicillin-binding protein encoded by mecA. Most multi-drug resistant (MDR) S. epidermidis (> or =2 resistance genes) were resistant to ampicillin, erythromycin and methicillin. All except one MDR S. epidermidis had icaAB, which encodes for polysaccharide intercellular adhesion. Based on pulsed field gel electrophoresis, MDR S. epidermidis were closely related genotypically, and were isolated from different cows on the

Identification and antimicrobial susceptibility patterns of Staphylococcus spp. isolated from canine chronic otitis externa

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Silva N.

2001-01-01

Full Text Available Swab samples obtained from 96 dogs with chronic otitis externa were cultured for the isolation of Staphylococcus species. Of 57 staphylococcal strains, 41 (72% were coagulase-negative (CNS. The identification of staphylococci strains was made by standard procedures for the routine identification of staphylococci in clinical practice. S. sciuri was the most frequent species isolated (22.8% from chronic otitis externa in dogs followed by S. intermedius (12.3%, S. auricularis (10.5% and S. aureus (8.8%. Three (5.2% CNS strains could not be identified. Bacterial isolates were susceptible to enrofloxacin, gentamicin, cephalothin, chloramphenicol and neomycin. Resistance was most common to penicillin G, oxacillin and ampicillin.

Antibiotic resistance and enterotoxin genes in Staphylococcus sp. isolates from polluted water in Southern Brazil.

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Basso, Ana P; Martins, Paula D; Nachtigall, Gisele; Van Der Sand, Sueli; De Moura, Tiane M; Frazzon, Ana Paula G

2014-12-01

The aim of this study was to evaluate the species distribution, antibiotic-resistance profile and presence of enterotoxin (SE) genes in staphylococci isolated from the Dilúvio stream in South Brazil. Eighty-eight staphylococci were identified, 93.18% were identified as coagulase-negative (CNS) and 6.82% coagulase-positive (CPS). Fourteen Staphylococcus species were detected and the most frequently were Staphylococcus cohnii (30.48%) and S. haemolyticus (21.95%). Resistance to erythromycin was verified in 37.50% of the strains, followed by 27.27% to penicillin, 12.50% to clindamycin, 6.81% to trimethoprim-sulfamethoxazole, 5.68% to chloramphenicol and 2.27% to norfloxacin. None of the investigated strains showed gentamicin and ciprofloxacin resistance. The strains were tested for the presence of sea, seb, sec, sed and see genes by PCR and only CNS strains (43.18%) showed positive results to one or more SE genes. The scientific importance of our results is due to the lack of data about these topics in polluted waters in Brazil. In conclusion, polluted waters from the Dilúvio stream may constitute a reservoir for disseminating antibiotic-resistance and enterotoxin into the community. In addition, the detection of staphylococci in the polluted waters of the Dilúvio stream indicated a situation of environmental contamination and poor sanitation conditions.

The Antibiotic Resistance Profiles of Bacterial Strains Isolated from Patients with Hospital-Acquired Bloodstream and Urinary Tract Infections

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Hamed Ghadiri

2012-01-01

Full Text Available Treatment of nosocomial infections is becoming difficult due to the increasing trend of antibiotics resistance. Current knowledge on antibiotic resistance pattern is essential for appropriate therapy. We aimed to evaluate antibiotic resistance profiles in nosocomial bloodstream and urinary tract pathogens. A total of 129 blood stream and 300 urinary tract positive samples were obtained from patients referring to Besat hospital over a two-year period (2009 and 2010. Antibiotic sensitivity was ascertained using the Kirby-Bauer disk diffusion technique according to CLSI guidelines. Patient's data such as gender and age were recorded. The ratio of gram-negative to gram-positive bacteria in BSIs was 1.6 : 1. The most prevalent BSI pathogen was Coagulase-Negative Staphylococci (CoNS. The highest resistance rate of CoNS was against penicillin (91.1% followed by ampicillin (75.6%, and the lowest rate was against vancomycin (4.4%. Escherichia coli was the most prevalent pathogen isolated from urinary tract infections (UTIs. Ratio of gram-negative to gram-positive bacteria was 3.2 : 1. The highest resistance rate of E. coli isolates was against nalidixic acid (57.7%. The present study showed that CoNS and E. coli are the most common causative agents of nosocomial BSIs and UTIs, and control of infection needs to be addressed in both antibiotic prescription and general hygiene.

Antimicrobial resistance and detection of mecA and blaZ genes in coagulase-negative Staphylococcus isolated from bovine mastitis

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Lidiane C. Soares

2012-08-01

Full Text Available The present study evaluated the pheno- and genotypical antimicrobial resistance profile of coagulase-negative Staphylococcus (CNS species isolated from dairy cows milk, specially concerning to oxacillin. Of 100 CNS isolates, the S. xylosus was the prevalent species, followed by S. cohnii, S. hominis, S. capitis and S. haemolyticus. Only 6% were phenotypically susceptible to the antimicrobial agents tested in disk diffusion assay. Penicillin and ampicillin resistance rates were significantly higher than others antimicrobials. Four isolates were positive to mecA gene (4%, all represented by the S. xylosus species. The blaZ gene was detected in 16% of the isolates (16/100. It was noticed that all mecA + were also positive to this gene and the presence of both genes was correlated to phenotypic beta-lactamic resistance. We conclude that CNS species from bovine milk presented significantly distinct antimicrobial resistance profiles, evaluated by phenotypic and genotypic tests, which has implications for treatment and management decisions.

Comparative effectiveness of linezolid versus vancomycin as definitive antibiotic therapy for heterogeneously resistant vancomycin-intermediate coagulase-negative staphylococcal central-line-associated bloodstream infections in a neonatal intensive care unit.

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Blanchard, A C; Fortin, E; Laferrière, C; Goyer, I; Moussa, A; Autmizguine, J; Quach, C

2017-06-01

Heterogeneously resistant vancomycin-intermediate coagulase-negative staphylococci (hVICoNS) are emerging pathogens causing central-line-associated bloodstream infections (CLABSIs) in neonatal intensive care unit (NICU) patients. Given the burden of disease associated with CLABSI and the current lack of therapeutic guidelines, we aimed to compare the effectiveness of linezolid versus vancomycin used as the definitive antibiotic therapy for hVICoNS CLABSI. We performed a retrospective cohort study of infants with hVICoNS CLABSI from a single NICU between 2009 and 2014, treated with either linezolid or vancomycin as definitive antibiotic therapy. CLABSI duration, early and late recurrence and in-hospital mortality were compared using propensity score-adjusted proportional hazards and logistic regression models. Of 89 infants with hVICoNS CLABSI, 33 (37.1%) treated with linezolid were compared with 56 (62.9%) treated with vancomycin. The median duration of CLABSI was 5 (range 1-12) versus 4 days (range 0-14) ( P  =   0.11), early recurrences were 3.0% versus 7.1% ( P  =   0.42), late recurrences 0% versus 14.3% ( P  =   0.02) and mortality 27.3% versus 28.6% ( P  =   0.90), when treated with linezolid versus vancomycin, respectively. When adjusting using a continuous propensity score, linezolid had an HR of 0.78 (95% CI 0.48-1.27) for CLABSI duration, an OR of 0.23 (95% CI 0.02-2.56) for early recurrence and an OR of 0.9 (95% CI 0.3-2.67) for mortality, relative to vancomycin. There was no statistically significant difference between linezolid and vancomycin when used as definitive treatment for hVICoNS CLABSI in NICU patients, in terms of CLABSI duration, recurrence or all-cause mortality. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Local host response following an intramammary challenge with Staphylococcus fleurettii and different strains of Staphylococcus chromogenes in dairy heifers

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Piccart , Kristine; Verbeke , Joren; De Visscher , Anneleen; Piepers , Sofie; Haesebrouck , Freddy; De Vliegher , Sarne

2016-01-01

International audience; AbstractCoagulase-negative staphylococci (CNS) are a common cause of subclinical mastitis in dairy cattle. The CNS inhabit various ecological habitats, ranging between the environment and the host. In order to obtain a better insight into the host response, an experimental infection was carried out in eight healthy heifers in mid-lactation with three different CNS strains: a Staphylococcus fleurettii strain originating from sawdust bedding, an intramammary Staphylococc...

A STUDY OF SUBCLINICAL MASTITIS IN TWO HERDS, ONE MANAGED ORGANICALLY, THE OTHER CONVENTIONALLY, AND THE EFFECT OF DIFFERENT MANAGEMENT STRATEGIES

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Thatcher, A.; Petrovski, K.; Shadbolt, N.; Martin, N.

2014-01-01

Mastitis in two herds managed as a comparison between organic and conventional dairy farming systems was monitored for 9 years utilising regular bacterial culture of milk samples, individual and bulk somatic cell counts and observation by farm staff. The most important isolates in pure cultures were coagulase-negative staphylococci, Staphylococcus aureus, Streptococcus uberis, and Bacillus spp. Positive cultures were generally not associated with subclinical mastitis. The objective was to dev...

Antistaphylococcal activity of DX-619, a new des-F(6)-quinolone, compared to those of other agents.

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Bogdanovich, Tatiana; Esel, Duygu; Kelly, Linda M; Bozdogan, Bülent; Credito, Kim; Lin, Gengrong; Smith, Kathy; Ednie, Lois M; Hoellman, Dianne B; Appelbaum, Peter C

2005-08-01

The in vitro activity of DX-619, a new des-F(6)-quinolone, was tested against staphylococci and compared to those of other antimicrobials. DX-619 had the lowest MIC ranges/MIC(50)s/MIC(90)s (microg/ml) against 131 Staphylococcus aureus strains (32), and ciprofloxacin (>32/>32). Raised quinolone MICs were associated with mutations in GyrA (S84L) and single or double mutations in GrlA (S80F or Y; E84K, G, or V) in all S. aureus strains tested. A recent vancomycin-resistant S. aureus (VRSA) strain (Hershey) was resistant to available quinolones and was inhibited by DX-619 at 0.25 microg/ml and sitafloxacin at 1.0 microg/ml. Vancomycin (except VRSA), linezolid, ranbezolid, tigecycline, and quinupristin-dalfopristin were active against all strains, and teicoplanin was active against S. aureus but less active against coagulase-negative staphylococci. DX-619 produced resistant mutants with MICs of 1 to >32 microg/ml after 32 microg/ml for ciprofloxacin, sitafloxacin, moxifloxacin, and gatifloxacin. DX-619 and sitafloxacin were also more active than other tested drugs against selected mutants and had the lowest mutation frequencies in single-step resistance selection. DX-619 and sitafloxacin were bactericidal against six quinolone-resistant (including the VRSA) and seven quinolone-susceptible strains tested, whereas gatifloxacin, moxifloxacin, levofloxacin, and ciprofloxacin were bactericidal against 11, 10, 7, and 5 strains at 4x MIC after 24 h, respectively. DX-619 was also bactericidal against one other VRSA strain, five vancomycin-intermediate S. aureus strains, and four vancomycin-intermediate coagulase-negative staphylococci. Linezolid, ranbezolid, and tigecycline were bacteriostatic and quinupristin-dalfopristin, teicoplanin, and vancomycin were bactericidal against two, eight, and nine strains, and daptomycin and oritavancin were rapidly bactericidal against all strains, including the VRSA. DX-619 has potent in vitro activity against staphylococci, including

Therapeutic effects of antimicrobial treatment during lactation of recently acquired bovine subclinical mastitis: two linked randomized field trials.

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van den Borne, B H P; van Schaik, G; Lam, T J G M; Nielen, M

2010-01-01

Two linked randomized field trials were performed on 39 herds in the Netherlands to 1) determine therapeutic effects of antimicrobial treatment of recently acquired subclinical mastitis (RASCM) during lactation, 2) evaluate the effect of duration of subclinical mastitis on therapeutic outcome, and 3) identify factors related to the therapeutic success of RASCM. Cows with a first elevated composite somatic cell count (CSCC) after 2 consecutive low CSCC measurements were eligible for enrollment in trial 1 (treatment at the first elevated CSCC). Quarter milk samples were collected to determine bacteriological status for major pathogens and coagulase-negative staphylococci. Cows with one or more culture-positive quarters with a quarter somatic cell count (QSCC) >or=100,000 cells/mL were defined to have RASCM and were randomly assigned treatment or control (no treatment). Untreated cows from trial 1 that had a second elevated CSCC at the next milk recording were eligible for enrollment in trial 2 (treatment at the second elevated CSCC). In trial 2, staphylococci-positive cows (Staphylococcus aureus and coagulase-negative staphylococci) were randomly assigned to treatment or control. Farmers used their own treatment protocols to treat quarters in both trials. Bacteriological cure was defined as absence of the pathogen identified pre-intervention in 2 samples post-intervention; QSCC, CSCC, and milk yield were also analyzed. Hierarchical logistic and linear models were used to determine therapeutic effects and to identify factors related to therapy outcome. Treated quarters had a higher bacteriological cure rate than control quarters for all pathogens in both trials. Treatment resulted in lower QSCC and CSCC, whereas milk yield was not affected by treatment. Bacteriological cure of RASCM was better in quarters with a low QSCC pre-intervention and in coagulase-negative staphylococci-positive quarters. Control quarters with a single culture-positive sample pre

Contaminant bacteria in traditional-packed honey

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Hening Tjaturina Pramesti

2007-03-01

Full Text Available Honey may be contaminated by microorganisms during its harvesting, processing, and packaging. Honey selected for clinical purposes must safe, sterile, and contain antimicrobial activity, so it must be evaluated using laboratory testing. The aim of this descriptive laboratory study was to isolate and identify the bacterial contaminant in the traditional-packed honey dealing with the use of honey for medical purposes. the colony forming units of honey sample cultured on blood agar were counted using Stuart bacterial colony counter. The suspected bacterial colonies were isolated and identified based on cultural morphology characteristics. The isolates of suspected bacterial colonies were stained according to Gram and Klein method and then were examined by the biochemical reaction. The results showed that there were two contaminant bacteria. Gram-positive cocci which were presumptively identified as coagulase-negative Staphylococci and gram-positive rods which were presumptively identified as Bacillus subtilis. In conclusion, the contaminant bacteria were regarded as low pathogen bacteria. The subtilin enzyme of B subtilis may cause an allergic reaction and coagulase-negative Staphylococci, Staphylococcus epidermidis is also an opportunist pathogen. Inevitably, for medical purposes, traditional-packed honey must be well filtered, water content above 18%, and standardized sterilization without loss of an antibacterial activity or change in properties.

Isolation of methicillin-resistant Staphylococcus pseudintermedius from breeding dogs.

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Rota, Ada; Milani, Chiara; Drigo, Ilenia; Drigo, Michele; Corrò, Michela

2011-01-01

The overuse of antimicrobials can select resistant bacteria strains; staphylococci have the ability to become resistant to all beta-lactam antimicrobials and are a significant concern in human medicine and a growing issue for veterinary medicine. Because antimicrobials are sometimes incorrectly used in breeding kennels, the objective of the work was to assess the occurrence of methicillin-resistant coagulase-positive staphylococci in breeding dogs. The research was carried out in 13 kennels that were allotted to three categories according to the intensity of antimicrobial use. Vaginal and milk swabs were taken from 87 healthy bitches around parturition and also from multiple organs of 27 of their pups that died within the first 2 weeks. Standard bacteriological examinations were carried out and coagulase-positive staphylococci were identified. All the coagulase-positive staphylococci resulted to be Staphylococcus pseudintermedius. Susceptibility to oxacillin and the presence of the mecA gene were tested. Nine out of 89 strains (six isolated from the bitches' milk and three from dead puppies, all belonging to kennels characterized by an excessive use of antimicrobials) were multidrug-resistant, methicillin-resistant and mecA positive. Our results confirm that excessive use of antimicrobials entails the risk of selecting resistant staphylococci strains. Our data also indicate that the bacterial flora of healthy dogs belonging to specific populations may act as a reservoir of resistance genes. Copyright © 2011 Elsevier Inc. All rights reserved.

Frequency and Antimicrobial Susceptibility of Coagulasenegative Staphylococci Isolated from Bovine Mastitis in Dairy Farms from Tolima, Colombia

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María del Pilar Sánchez Bonilla

2015-09-01

Full Text Available Objective: To determine the antimicrobial presence and susceptibility of the coagulase-negative staphylococci group (ECN, for its initials in Spanish in some cattle farms from Tolima, Colombia. Materials and methods: Using the California test for the diagnosis of mastitis (CMT, for its initials in Spanish, 484 quarters belonging to 121 cows from five small production ranches from a region of central Tolima were evaluated. CMT positive samples were cultivated for bacterial isolation. The ECN found were tested for susceptibility to the antibiotics. The results were analyzed with descriptive statistics. Results: 252 (52% quarters did not show any type of reaction to the CMT, nor did they show any clinical signs of mastitis, therefore they were considered free of the disease. From the quarters, 73 (15% turned positive for CMT and bacteriological culture. From these, 36 strains of ECN were isolated (7.4% of the total of quarters; S. aureus-ECP, 28 (5.8%; Streptococcus spp., 6 (1.2%.; Escherichia coli, 2 (0.4%, and Klebsiella pneumoniae, 2 (0.2%. The clinical and subclinical mastitis in the quarter occurred in 1.4% and 13.6%, respectively. In 5 (1.0% of the quarters, clinical mastitis caused by ECN was found and subclinical mastitis in 31 (6.4%. 61% of the ECN strains were resistant to penicillin, and 58%, to tetracycline; 97% were sensitive to cefoperazone. Conclusion: The ECN group, considered a global emergent of mastitis, is evidenced with high frequency in ranches from Tolima, Colombia, causing clinical and subclinical mastitis with varied response to antimicrobials.

ClpP-Independent Function of ClpX Interferes with Telithromycin Resistance Conferred by Msr(A) in Staphylococcus aureus

Czech Academy of Sciences Publication Activity Database

Vimberg, Vladimír; Lenart, Jakub; Janata, Jiří; Balíková Novotná, Gabriela

2015-01-01

Roč. 59, č. 6 (2015), s. 3611-3614 ISSN 0066-4804 R&D Projects: GA MŠk(CZ) EE2.3.20.0055; GA ČR GPP302/12/P632; GA MŠk(CZ) EE2.3.30.0003; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:61388971 Keywords : COAGULASE-NEGATIVE STAPHYLOCOCCI * ZINC-BINDING DOMAIN * STRESS TOLERANCE Subject RIV: EE - Microbiology, Virology Impact factor: 4.415, year: 2015

Antibiotic resistance and enterotoxin genes in Staphylococcus sp. isolates from polluted water in Southern Brazil

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ANA P. BASSO

2014-12-01

Full Text Available The aim of this study was to evaluate the species distribution, antibiotic-resistance profile and presence of enterotoxin (SE genes in staphylococci isolated from the Dilúvio stream in South Brazil. Eighty-eight staphylococci were identified, 93.18% were identified as coagulase-negative (CNS and 6.82% coagulase-positive (CPS. Fourteen Staphylococcus species were detected and the most frequently were Staphylococcus cohnii (30.48% and S. haemolyticus (21.95%. Resistance to erythromycin was verified in 37.50% of the strains, followed by 27.27% to penicillin, 12.50% to clindamycin, 6.81% to trimethoprim-sulfamethoxazole, 5.68% to chloramphenicol and 2.27% to norfloxacin. None of the investigated strains showed gentamicin and ciprofloxacin resistance. The strains were tested for the presence of sea, seb, sec, sed and see genes by PCR and only CNS strains (43.18% showed positive results to one or more SE genes. The scientific importance of our results is due to the lack of data about these topics in polluted waters in Brazil. In conclusion, polluted waters from the Dilúvio stream may constitute a reservoir for disseminating antibiotic-resistance and enterotoxin into the community. In addition, the detection of staphylococci in the polluted waters of the Dilúvio stream indicated a situation of environmental contamination and poor sanitation conditions.

Glucose & sodium chloride induced biofilm production & ica operon in clinical isolates of staphylococci

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Astha Agarwal

2013-01-01

Full Text Available Background & objectives: All colonizing and invasive staphylococcal isolates may not produce biofilm but may turn biofilm producers in certain situations due to change in environmental factors. This study was done to test the hypothesis that non biofilm producing clinical staphylococci isolates turn biofilm producers in presence of sodium chloride (isotonic and high concentration of glucose, irrespective of presence or absence of ica operon. Methods: Clinical isolates of 100 invasive, 50 colonizing and 50 commensal staphylococci were tested for biofilm production by microtiter plate method in different culture media (trypticase soy broth alone or supplemented with 0.9% NaCl/ 5 or 10% glucose. All isolates were tested for the presence of ica ADBC genes by PCR. Results: Biofilm production significantly increased in the presence of glucose and saline, most, when both glucose and saline were used together. All the ica positive staphylococcal isolates and some ica negative isolates turned biofilm producer in at least one of the tested culture conditions. Those remained biofilm negative in different culture conditions were all ica negative. Interpretation & conclusions: The present results showed that the use of glucose or NaCl or combination of both enhanced biofilm producing capacity of staphylococcal isolates irrespective of presence or absence of ica operon.

Long-term outcome of acute prosthetic joint infections due to gram-negative bacilli treated with retention of prosthesis.

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Jaén, N; Martínez-Pastor, J C; Muñoz-Mahamud, E; García-Ramiro, S; Bosch, J; Mensa, J; Soriano, A

2012-09-01

To update the clinical information of the 47 patients with a prosthetic joint infection due to Gram-negative bacilli included in a previous study and to reassess the predictors of failure after a longer follow-up. Using the electronic files of our hospital, all the information regarding readmissions to the hospital, new surgical procedures and the reason for the new surgery (infection, aseptic loosening), and the last visit in the hospital were registered. The medical chart of the 35 patients that were considered in remission in the previous publication was reviewed. In 30 patients no clinical evidence of failure was detected and no additional surgery on the previously infected prosthesis was necessary and they were considered in long-term remission. In 5 cases a late complication was identified. One case had a reinfection due to coagulase-negative staphylococci after 22 months from the open debridement and required a 2-stage revision surgery. The other 4 cases developed an aseptic loosening and it was necessary to perform a 1-stage exchange. Receiving a fluoroquinolone when all the Gram-negatives involved in the infection were susceptible to fluoroquinolones was the only factor associated with remission in the univariate analysis (p=0.002). After a long-term follow-up, our results support the importance of using fluoroquinolones in acute PJI due to Gram-negative bacilli.

Identification of Staphylococcus spp. isolated during the ripening process of a traditional minas cheese

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B.M. Borelli

2011-04-01

Full Text Available The population dynamics of Staphylococcus spp. was studied during the ripening of Canastra Minas cheese at three farms located in the State of Minas Gerais, Brazil. The presence of coagulase (coa, thermonuclease (nuc, and enterotoxin (sea, seb, sec, and sed genes was investigated in Staphylococcus strains isolated during the 60-day cheese-ripening period. The presence of the staphylococcal enterotoxins A, C, and D was also investigated in the cheese samples. Cheese samples that were matured for 0, 7, 15, 30, and 45 days presented staphylococci counts from 10³ to 10(8cfu/g. All isolates considered coagulase-positive by physiological tests had the coa gene. However, no association was observed between the results obtained with biochemical tests and those obtained by PCR using gene-specific primers for coagulase-negative strains. Coagulase and thermonuclease genes occurred simultaneously in 41.3% of Staphylococcus spp. tested. None of the investigated Staphylococcus strains expressed enterotoxins SEA, SEB, SEC, and SED. Enterotoxins A, C, and D were not detected in any of the cheese samples.

Conjunctival endogenous microbiota in patients submitted to cataract surgery Microbiota endógena conjuntival em pacientes submetidos à cirurgia de catarata

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Claudete I. Locatelli

2003-07-01

Full Text Available Bacterial isolation, identification and antimicrobial susceptibility tests were carried out in ocular material collected with swab and polimethylmethacrylate (PMMA or silicone intraocular lenses (IOL from forty six patients submitted to cataract surgery. Seventy six isolates and seven different microorganisms were identified. Coagulase-negative staphylococci (CNS were the predominant microorganisms isolated from swabs (71.4% of cases, PMMA lenses (81.3% and silicon lenses (77.8%. Coagulase-negative staphylococci isolates revealed high resistance to penicillin G followed by tetracycline, chloramphenicol and aminoglicosides. However, these isolates displayed great susceptibility to vancomycin, cephalothin and ofloxacin. Except for penicillin G, Staphylococcus aureus was very sensitive to the antimicrobial agents including oxacillin. Among Gram-negatives, Proteus mirabilis was prevalent and presented high resistance to tetracycline and chloramphenicol. Enterococcus isolates were vancomycin sensitive.A partir de material ocular coletado de 46 pacientes submetidos à cirurgia de catarata foram realizados isolamento, identificação e teste de susceptibilidade de microrganismos frente a antimicrobianos, utilizando-se suabes e lentes intraoculares (LIO. Foram obtidos 76 isolados e identificados 7 tipos de microrganismos. Estafilococos coagulase-negativos (CNS foram os microrganismos mais freqüentemente detectados de suabes (71,4% dos casos, lentes de PMMA (81,3% e lentes de silicone (77,8%. Isolados de CNS apresentaram elevada resistência à penicilina G, seguida por tetraciclina, cloranfenicol e aminoglicosídeos. No entanto, estes isolados mostraram grande sensibilidade à vancomicina, cefalotina e ofloxacina. Com exceção da penicilina G, os isolados de Staphylococcus aureus foram bastante sensíveis aos agentes antimicrobianos, incluindo a oxacilina. Entre as gram-negativas, Proteus mirabilis foi a bactéria mais freqüente e também se mostrou

Diversity and antimicrobial susceptibility profiling of staphylococci isolated from bovine mastitis cases and close human contacts.

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Schmidt, T; Kock, M M; Ehlers, M M

2015-09-01

The objectives of this study were to examine the diversity of Staphylococcus spp. recovered from bovine intramammary infections and humans working in close contact with the animals and to evaluate the susceptibility of the staphylococcal isolates to different antimicrobials. A total of 3,387 milk samples and 79 human nasal swabs were collected from 13 sampling sites in the KwaZulu-Natal province of South Africa. In total, 146 Staph. aureus isolates and 102 coagulase-negative staphylococci (CNS) were recovered from clinical and subclinical milk samples. Staphylococcusaureus was isolated from 12 (15.2%) of the human nasal swabs and 95 representative CNS were recovered for further characterization. The CNS were identified using multiplex-PCR assays, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), and tuf gene sequencing. Seven Staphylococcus spp. were identified among the CNS of bovine origin, with Staph.chromogenes (78.4%) predominating. The predominant CNS species recovered from the human nasal swabs was Staph.epidermidis (80%) followed by Staph.chromogenes (6.3%). The antimicrobial susceptibility of all staphylococcal isolates was evaluated using disk diffusion and was supplemented by screening for specific antimicrobial resistance genes. Ninety-eight (67.1%) Staph.aureus isolates of bovine origin were pansusceptible; 39 (26.7%) isolates were resistant to a single class, and 7 (4.8%) isolates were resistant to 2 classes of antimicrobials. Two Staph. aureus (1.4%) isolates were multidrug-resistant. Resistance to penicillin was common, with 28.8% of the bovine and 75% of the human Staph. aureus isolates exhibiting resistance. A similar observation was made with the CNS, where 37.3% of the bovine and 89.5% of the human isolates were resistant to penicillin. Multidrug-resistance was common among the human CNS, with 39% of the isolates exhibiting resistance to 3 or more classes of antimicrobials. The antimicrobial

Central Venous Catheter (CVC related infections: a local retrospective study

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Manuela Fresu

2008-06-01

Full Text Available Background. Central venous catheter (CVC related infection is associated with significant increases in morbidity, mortality, and health care cost.This local surveillance study was carry out to monitor the frequency of occurrence of CVC-related blood stream infections. Materials and methods. During the period January – December 2005, 226 CVC specimens were analyzed (quantitative method and microrganism identification from positive samples was performed by Vitek II. In 53 patients it was possible to compare quantitative results with those obtained from blood cultures. Results. Positive CVC samples were 125 (55% and 130 microrganisms were isolated: 109 Gram-positives (84%, 4 Gram-negatives (3%, and 17 mycetes (13%. Among pathogens collected simultaneously from CVC and blood samples, the most frequently isolated were Staphylococcus spp. (30% coagulase-negative staphylococci and 20%. S. aureus and Candida spp. (45%. In the group of patients that presented positive CVC and negative blood samples the most frequently recovered microrganisms were staphylococci. Many isolates (33% were polymicrobial. Conclusions. Catheter-related infections occurred in those patients who presented the same pathogen in both CVC and blood cultures. These infections were principally caused by staphylococci and Candida spp. On the contrary, a possible CVC contamination could be suspected when positive CVC and negative blood cultures were found.

Prevalence and antimicrobial susceptibility patterns of bacteria from milkmen and cows with clinical mastitis in and around Kampala, Uganda.

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David Patrick Kateete

Full Text Available BACKGROUND: Identification of pathogens associated with bovine mastitis is helpful in treatment and management decisions. However, such data from sub-Saharan Africa is scarce. Here we describe the distribution and antimicrobial susceptibility patterns of bacteria from cows with clinical mastitis in Kampala, Uganda. Due to high concern of zoonotic infections, isolates from milkmen are also described. METHODOLOGY/PRINCIPAL FINDINGS: Ninety seven milk samples from cows with clinical mastitis and 31 nasal swabs from milkmen were collected (one sample per cow/human. Fifty eight (60% Gram-positive isolates namely Staphylococci (21, Enterococci (16, Streptococci (13, Lactococci (5, Micrococci (2 and Arcanobacteria (1 were detected in cows; only one grew Staphylococcus aureus. Furthermore, 24 (25% coliforms namely Escherichia coli (12, Klebsiella oxytoca (5, Proteus vulgaris (2, Serratia (2, Citrobacter (1, Cedecea (1 and Leclercia (1 were identified. From humans, 24 Gram-positive bacteria grew, of which 11 were Staphylococci (35% including four Staphylococcus aureus. Upon susceptibility testing, methicillin-resistant coagulase-negative staphylococci (CoNS were prevalent; 57%, 12/21 in cows and 64%, 7/11 in humans. However, methicillin-resistant Staphylococcus aureus was not detected. Furthermore, methicillin and vancomycin resistant CoNS were detected in cows (Staphylococcus hominis, Staphylococcus lugdunensis and humans (Staphylococcus scuiri. Also, vancomycin and daptomycin resistant Enterococci (Enterococcus faecalis and Enterococcus faecium, respectively were detected in cows. Coliforms were less resistant with three pan-susceptible isolates. However, multidrug resistant Klebsiella, Proteus, Serratia, Cedecea, and Citrobacter were detected. Lastly, similar species grew from human and bovine samples but on genotyping, the isolates were found to be different. Interestingly, human and bovine Staphylococcus aureus were genetically similar (spa-CC435

Contribution of natural milk culture to microbiota, safety and hygiene of raw milk cheese produced in alpine malga

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Rosaria Lucchini

2018-04-01

Full Text Available Processing of alpine milk in malga farms is carried out under conditions that can favor contamination by coliforms, coagulase-positive staphylococci, or pathogens such as Listeria monocytogenes. With the aim to improve the hygienic characteristics and safety of cheese produced in four malga farms the use of lyophilized Natural Milk Culture prepared with selected strains was tested. Two cheesemaking tests were carried out in the same day always starting from the same milk: in the first case following the malga recipe that uses either Natural Whey Culture or without the addition of a starter, in the second one using a Natural Milk Culture. Cheesemaking were carried out in four malga farms located in the west area of Trentino region within the same week. For hygienic and safety evaluation, aerobic colony count, coagulase-positive staphylococci, Escherichia coli, staphylococcal toxins, Listeria monocytogenes , and Salmonella spp, pH and aw were determined in raw milk from evening and morning milking, curd in vat, curd after extraction and two months-ripened cheese. Pathogens or toxins, high values of coagulase- positive staphylococci and E. coli were not found in cheese samples. However, in the curd coagulase-positive staphylococci reached values almost of 5 Log CFU/g in the two malga without starter cultures. The use of Natural Milk Culture reduced E. coli counts. In addition, DNA was extracted from cheese samples and from Natural Milk Culture and the composition of the microbial community determined by Next Generation Sequencing method. The determination of cheese microbial communities demonstrated that the use of Natural Milk Culture exerted different effects in the different malga, in any case preserving bacterial biodiversity.

Ocorrência de Staphylococcus sp. em água utilizada em propriedades leiteiras do Estado de São Paulo Incidence of Staphylococcus sp. in the water used by dairy farms in the State of Sao Paulo

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L.A. Amaral

2003-10-01

Full Text Available Com o objetivo de verificar o papel da água utilizada durante a produção do leite como via de transmissão de Staphylococcus sp., fez-se a contagem de Staphylococcus coagulase negativa e Staphylococcus aureus nas amostras de água das fontes, dos reservatórios e dos estábulos de 30 propriedades leiteiras situadas na região Nordeste do Estado de São Paulo. As maiores ocorrências de isolamentos (10,0 e 16,6% e os maiores valores médios (4,3×10(4 e 2,5×10(4 de contagens desses microrganismos foram encontrados nas amostras de água dos estábulos utilizada na obtenção de leite. Estes resultados são importantes pois evidenciam a possibilidade de contaminação do leite ou dos animais por cepas patogênicas.With the objective to verify the role of the water in the transmission of Staphylococcus sp., the counting of coagulase negative staphylococci, and Staphylococcus aureus in the water samples of the sources, reservoirs, and stables of 30 dairy farms, located in the Northeast region of the State of São Paulo was carried out. The major occurrence of coagulase negative staphylococci and Staphylococcus aureus, respectively, 10.0%, and 16.6%, were found in the water used for milking, with the major average of counting of 4.3×10(4 and 2.5×10(4. The results show the risk of water as a vehicle for transmission of mastitis, and the possibility of milk contamination by strains responsible for foodborne diseases.

Case report of a pustular dermatitis outbreak in sheep: Clinical and food safety considerations

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Mariana Roccaro

2018-04-01

Full Text Available The objective of this report is to describe an outbreak of pustular dermatitis in a flock of about 200 sheep, its clinical evolution and food safety implications. The onset of the symptoms was sudden and the lesions spread very quickly from ewe to ewe, so that in about 3 days almost all of the lactating sheep were stricken. Pustules from 5 different animals, six milk samples, two cheese samples, teat cup samples from the milking machine and farmer’s hands were analysed. A pure culture of Staphylococcus aureus, producing staphylococcal enterotoxin (SE C, was isolated from pustules. Milk and cheese showed a contamination by coagulase positive staphylococci <15 and 30 colony forming units respectively and the absence of SE. Farmer’s hands and teat cups samples resulted negative for coagulase positive staphylococci. Therapy with daily topical medicaments was prescribed and a prophylactic intervention was suggested by the administration of an autovaccine. The low level of milk and cheese contamination and the absence of SE in cheese supported the decision to not advise the farmer to recall cheese produced with milk from affected animals.

Detection of pathogenic bacteria in skin lesions of patients with chiclero's ulcer: reluctant response to antimonial treatment

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Isaac-Márquez Angélica Patricia

2003-01-01

Full Text Available We investigated the bacterial flora present in skin lesions of patients with chiclero's ulcer from the Yucatan peninsula of Mexico using conventional culture methods (11 patients, and an immunocolorimetric detection of pathogenic Streptococcus pyogenes (15 patients. Prevalence of bacteria isolated by culture methods was 90.9% (10/11. We cultured, from chiclero's ulcers (60%, pathogenic bacterial such as Staphylococcus aureus (20%, S. pyogenes (1.6%, Pseudomonas aeruginosa (1.6%, Morganella morganii (1.6%, and opportunist pathogenic bacteria such as Klebsiella spp. (20.0%, Enterobacter spp. (20%, and Enterococcus spp. (20%. We also cultured coagulase-negative staphylococci in 40% (4/10 of the remaining patients. Micrococcus spp. and coagulase-negative staphylococci constituted the bacterial genuses more frequently isolated in the normal skin of patients with chiclero's ulcer and healthy individuals used as controls. We also undertook another study to find out the presence of S. pyogenes by an immunocolorimetric assay. This study indicated that 60% (9/15 of the ulcerated lesions, but not normal controls, were contaminated with S. pyogenes. Importantly, individuals with purulent secretion and holding concomitant infections with S. pyogenes, S. aureus, P. aeruginosa, M. morganii, and E. durans took longer to heal Leishmania (L. mexicana infections treated with antimonial drugs. Our results suggest the need to eliminate bacterial purulent infections, by antibiotic treatment, before starting antimonial administration to patients with chiclero's ulcer.

Evaluation of a culture-based pathogen identification kit for bacterial causes of bovine mastitis.

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Viora, L; Graham, E M; Mellor, D J; Reynolds, K; Simoes, P B A; Geraghty, T E

2014-07-26

Accurate identification of mastitis-causing bacteria supports effective management and can be used to implement selective use of antimicrobials for treatment. The objectives of this study were to compare the results from a culture-based mastitis pathogen detection test kit ('VetoRapid', Vétoquinol) with standard laboratory culture and to evaluate the potential suitability of the test kit to inform a selective treatment programme. Overall 231 quarter milk samples from five UK dairy farms were collected. The sensitivity and specificity of the test kit for the identification of Escherichia coli, Staphylococcus aureus, coagulase-negative staphylococci, Streptococcus uberis and Enterococcus spp. ranged from 17 per cent to 84 per cent and 92 per cent to 98 per cent, respectively. In total, 23 of 68 clinical samples were assigned as meeting the requirement for antimicrobial treatment (Gram-positive organism cultured) according to standard culture results, with the test kit results having sensitivity and specificity of 91 per cent and 78 per cent, respectively. Several occurrences of misidentification are reported, including S. aureus being misidentified as coagulase-negative staphylococci and vice versa. The test kit provides rapid preliminary identification of five common causes of bovine mastitis under UK field conditions and is likely to be suitable for informing selective treatment of clinical mastitis caused by Gram-positive organisms. British Veterinary Association.

Inducible Clindamycin Resistance in Staphylococcus Species

International Nuclear Information System (INIS)

Afridi, F. I.; Zeb, M.; Farooqi, B. J.; Murtaza, G.; Hussain, A.

2014-01-01

Objective: To determine the frequency of inducible clindamycin resistance in clinical isolates of Staphylococcus species by phenotypic D-test. Study Design: Observational study. Place and Duration of Study: Ziauddin University Hospital, Karachi, from July to December 2011. Methodology: Consecutive clinical isolates of Staphylococcus species were collected and identified by conventional microbiological techniques. Antimicrobial susceptibility testing and inducible clindamycin resistance was carried out by performing D-test using CLSI criteria. Methicillin resistance was detected by using Cefoxitin disk as a surrogate marker. Statistical analysis was performed by SPSS version-17. Results: A total of 667 clinical isolates of Staphylococcus species were obtained during the study period. In these isolates, 177 (26.5%) were Staphylococcus aureus, and 490 (73.5%) were coagulase negative Staphylococci. The total frequency of inducible clindamycin resistance among isolates of Staphylococcus species was 120/667 (18%). Frequency of inducible clindamycin resistance among coagulase negative Staphylococci group and Staphylococcus aureus group were 18.57% and 16.38% respectively. Median age of patients in D-test positive group was 19.5 (1 - 54) years. Conclusion: The frequency of inducible clindamycin resistance among Staphylococcus species may differ in different hospital setup. Clinical microbiology laboratories should implement testing simple and effective D-test on all Staphylococcus species. D-test positive isolates should be reported clindamycin resistant to decrease treatment failure. (author)

Interpretive criteria for mupirocin susceptibility testing of Staphylococcus spp. using CLSI guidelines.

LENUS (Irish Health Repository)

Creagh, S

2012-02-03

Mupirocin is an antimicrobial agent commonly used to treat staphylococcal infection or to eliminate persistent carriage. To date, interpretive criteria have not been established to define susceptibility or resistance when performing mupirocin susceptibility testing. In this evaluation, using CLSI guidelines, a total of 502 staphylococci comprising 219 methicillin-sensitive Staphylococcus aureus, 222 methicillin-resistant S. aureus and 61 coagulase-negative staphylococci are tested by broth microdilution, disc diffusion and E-test. Disc diffusion using 5 microg mupirocin discs was found to be a reliable method to distinguish susceptible and resistant strains. Minimum inhibitory concentration (MIC) determination was required to differentiate low-level and high-level resistance to mupirocin. E-test was found to be an accurate alternative to broth microdilution for the routine determination of MIC values of staphylococci to mupirocin. Broth microdilution and disc-diffusion results were plotted on a scattergram, and error rates were calculated. No errors were found using susceptibility criteria of < 4 microg\\/mL (MIC) and > 19 mm (zone diameter).

Risk factors and impacts of clinical and subclinical mastitis in commercial meat-producing sheep flocks in Quebec, Canada.

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Arsenault, Julie; Dubreuil, Pascal; Higgins, Robert; Bélanger, Denise

2008-11-17

We conducted a prospective observational study on clinical and subclinical mastitis in 30 commercial meat-producing sheep flocks from 2 regions of the province of Quebec, Canada. A total of 2,792 ewes selected in late gestation were followed from lambing to weaning of lambs. The incidence of clinical mastitis for the total lactation period (average of 58 days) ranged among flocks from 0 to 6.6%, with a median of 1.2%. The most frequently isolated bacteria from the cases of clinical mastitis, in pure or mixed culture, were Mannheimia haemolytica (26%), Staphylococcus aureus (23%), and coagulase-negative staphylococci (17%). Incidence of clinical mastitis was higher in ewes that gave birth to 3 or more lambs and from the Estrie region, and was associated with an increase in ewe mortality, an increase in lamb mortality at the litter level, and a decrease in lamb's weaning weight for lambs born in multiple litter size or from ewes >or=4 years old. Among 354 selected ewes with clinically normal udder at the end of lactation, 28.8% had potentially pathogenic bacteria isolated from milk. The most prevalent bacteria were S. aureus (9.3%) and coagulase-negative staphylococci (9.3%). The risk of having a positive culture in at least one half was different between the two regions. Prevalence of ewes (n=261) with California Mastitis Test (CMT) positive result in at least one half was 24.1 and 14.9% using a cut-off of >or=1+ and >or=2+, respectively. Prevalence of culture-positive udder halves was 11.7% for CMT-negative compared with 53.6% for CMT 3+ halves. CMT status was positively associated with the isolation of coagulase-negative staphylococci, M. haemolytica, S. aureus, and various Streptococcus species, but not with other isolated bacteria. Additionally, prevalence of CMT-positive halves was higher in ewes from the Estrie region, aged of >or=4 years versus 1 year, having clinical mastitis previously detected in the lactation and/or with low body condition score. Lamb

Normal flora of conjunctiva and lid margin, as well as its antibiotic sensitivity, in patients undergoing cataract surgery at Phramongkutklao Hospital.

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Ratnumnoi, Ravee; Keorochana, Narumon; Sontisombat, Chavalit

2017-01-01

This study aimed to evaluate the normal flora of conjunctiva and lid margin, as well as its antibiotic sensitivity. This was a prospective cross-sectional study. A prospective study was conducted on 120 patients who underwent cataract surgery at the Phramongkutklao Hospital from September 2014 to October 2014. Conjunctival and lid margin swabs were obtained from patients before they underwent cataract surgery. These swabs were used to inoculate blood agar and chocolate agar plates for culturing. After growth of the normal flora, the antibiotic sensitivity method using tobramycin, moxifloxacin, levofloxacin, and cefazolin was applied. Normal flora of conjunctiva and lid margin, along with its antibiotic sensitivity, from patients who underwent cataract surgery was assessed. A total of 120 eyes were included in this study, and bacterial isolation rates were identified. Five bacteria from the lid margin were cultured, namely, coagulase-negative staphylococcus (58.33%), Streptococcus spp. (2.5%), Corynebacterium (1.67%), Micrococcus spp. (1.67%), and Staphylococcus aureus (0.83%). Two bacteria from the conjunctiva were cultured, namely, coagulase-negative staphylococcus (30%) and Streptococcus spp. (0.83%). Results of antibiotic sensitivity test showed that all isolated bacteria are sensitive to cefazolin 100%, tobramycin 98.67%, levofloxacin 100%, and moxifloxacin 100%. Coagulase-negative staphylococci are the most common bacteria isolated from conjunctiva and lid margin.

Staphylococcus epidermidis adhesion and biofilm formation onto biomaterials

OpenAIRE

Sousa, Cláudia

2009-01-01

Tese de doutoramento em Engenharia Química e Biológica Staphylococcus epidermidis is a coagulase-negative Staphylococcus (CNS) that often colonizes the skin and mucous membranes of the human body, as part of its normal microflora. However, when a rupture of the cutaneous surface occurs, by any type of trauma or insertion of a medical device, staphylococci can enter the host and become pathogenic. Therefore, S. epidermidis has emerged in recent years as a major nosocomial pathogen associate...

Cultural characters of a newly recognized group of hospital staphylococci.

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Jevons, M P; John, M; Parker, M T

1966-07-01

Members of a newly recognized group of hospital staphylococci, which are believed to have arisen from 83A staphylococci by lysogenization, differ from them in several cultural characters. Some but not all of these characters appear to be determined by the carriage of phage.

Growth of enterotoxigenic Staphylococcus aureus in povi masima, a traditional Pacific island food.

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Wong, T L; Whyte, R J; Graham, C G; Saunders, D; Schumacher, J; Hudson, J A

2004-01-01

To obtain preliminary data on the microbiology and hurdles to pathogen growth in the traditional Pacific Island food, povi masima, which is essentially beef brisket cured in brine. Six containers of povi masima were prepared and two were inoculated with five enterotoxigenic strains of Staphyloccocus aureus. The povi masima were divided into two lots each containing two uninoculated control and an inoculated container. Lot 1 was incubated at room temperature (20 degrees C) and lot 2 under refrigeration (4-5 degrees C) for up to 98 days. During storage, samples were removed and tested for aerobic plate count, coagulase-producing Staphylococci, Clostridium perfringens, staphylococcal enterotoxin and various chemical parameters of the food. Coagulase-producing Staphylococci and aerobic plate counts grew to high levels in both the inoculated and uninoculated lots stored at room temperature, but enterotoxin was only detected at one time point in these lots and this may represent a false positive result. The concentration of NaCl in the meat increased with time as concentrations equilibrated, and nitrite was rapidly lost in those lots stored at room temperature. Storage at 4-5 degrees C prevented proliferation of coagulase-producing Staphylococci. For safe curing and storage, this food should be kept under refrigeration as this prevented growth of staphylococci. Optimum storage would also be achieved with improved attempts to ensure equal distribution of NaCl prior to storage. Under conditions traditionally used to cure and store this food, enterotoxigenic staphylococci can grow to numbers where toxigenesis might occur, especially during the early stages of curing where the salt has not diffused from the brine into the meat.

Pathogen-specific effects of quantitative trait loci affecting clinical mastitis and somatic cell count in danish holstein cattle

DEFF Research Database (Denmark)

Sørensen, Lars Peter; Guldbrandtsen, Bernt; Thomasen, J.R.

2008-01-01

The aim of this study was to investigate whether quantitative trait loci (QTL) affecting the risk of clinical mastitis (CM) and QTL affecting somatic cell score (SCS) exhibit pathogen-specific effects on the incidence of mastitis. Bacteriological data on mastitis pathogens were used to investigate...... pathogen specificity of QTL affecting treatments of mastitis in first parity (CM1), second parity (CM2), and third parity (CM3), and QTL affecting SCS. The 5 most common mastitis pathogens in the Danish dairy population were analyzed: Streptococcus dysgalactiae, Escherichia coli, coagulase...... against coagulase-negative staphylococci and Strep. uberis. Our results show that particular mastitis QTL are highly likely to exhibit pathogen-specificity. However, the results should be interpreted carefully because the results are sensitive to the sampling method and method of analysis. Field data were...

Biofilm Formation by Bacteria Isolated from Intravenous Catheters

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Sina Hedayati

2015-10-01

Full Text Available Background: Reports on the association of nosocomial bacterial infections with indwelling medical devices such as intravenous catheters (IVC has increased in recent years. The potential to form biofilm on these devices seems to be the main reason for establishment of such infections. The aim of this study was to measure the potential of biofilm formation by bacterialisolates from IVCs.Methods: Seventy-one IVCs were collected from hospitalized patients in ICU, NICU, hematology and oncology wards at Taleghani Hospital from Jan 2010 to Jan 2011. The bacterial isolates were identified using the standard biochemical tests and the potential to form biofilms was determined by the microtiter plate assay method (MTP and colony morphology using Congo red agar plates (CRA.Results: Overall, 54 (71% IVCs were colonized and 76 bacteria were isolated among which, 64 (84.2% were coagulase negative staphylococci (CoNS, 3 (3.9% S. aureus, 3 (3.9% Enterococcus spp., 2 (2.6% E. coli and 4 (5.3% were miscellaneous isolates not further identified. Among the CoNS, biofilm formation was observed in 68.7% and 82.8% of bacteriausing MTP and CRA methods, respectively. S. aureus and E. coli isolates also were biofilm producers but Enterococcus and other unknown isolates were biofilm negative.Conclusions: Our results confirm that the prevalent biofilm forming bacteria on IVCs were CoNS and that was the reason for high rates of nosocomial infections.

[Pyomyositis, sacroiliitis and spondylodiscitis caused by Staphylococcus hominis in a immunocompetent woman].

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Gómez Rodríguez, N; Durán Muñoz, O

2006-12-01

In absence of risk factors, osteoarticular infections by coagulase-negative staphylococci are very infrequent. We described the case of a immunocompetent 73-year-old-woman that suffered pyomyositis, left sacroiliitis and spondylodiscitis involving the first and second thoracic vertebrae by Staphylococcus hominis. This multifocal infection occurred five-weeks after intramuscular administration of NSAI for treatment of low back pain associated with a herniated disc L4-L5. This is the first know case of a multifocal muscle skeletal infection by Staphylococcus hominis in a patient immunocompetent.

Molecular epidemiology of clinical and carrier strains of methicillin resistant Staphylococcus aureus (MRSA in the hospital settings of north India

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Dar Mohammad J

2006-09-01

Full Text Available Abstract Background The study was conducted between 2000 and 2003 on 750 human subjects, yielding 850 strains of staphylococci from clinical specimens (575, nasal cultures of hospitalized patients (100 and eye & nasal sources of hospital workers (50 & 125 respectively in order to determine their epidemiology, acquisition and dissemination of resistance genes. Methods Organisms from clinical samples were isolated, cultured and identified as per the standard routine procedures. Susceptibility was measured by the agar diffusion method, as recommended by the Nat ional Committee for Clinical Laboratory Standards (NCCLS. The modified method of Birnboin and Takahashi was used for isolation of plasmids from staphylococci. Pulsed-field gel electrophoresis (PFGE typing of clinical and carrier Methicillin resistant Staphylococcus aureus (MRSA strains isolated during our study was performed as described previously. Results It was shown that 35.1% of Staphylococcus aureus and 22.5% of coagulase-negative staphylococcal isolates were resistant to methicillin. Highest percentage of MRSA (35.5% was found in pus specimens (n = 151. The multiple drug resistance of all MRSA (n = 180 and Methicillin resistant Coagulase-negative Staphylococcus aureus (MRCNS (n = 76 isolates was detected. In case of both methicillin-resistant as well as methicillin-sensitive Saphylococcal isolates zero resistance was found to vancomycin where as highest resistance was found to penicillin G followed by ampicillin. It was shown that the major reservoir of methicillin resistant staphylococci in hospitals are colonized/infected inpatients and colonized hospital workers, with carriers at risk for developing endogenous infection or transmitting infection to health care workers and patients. The results were confirmed by molecular typing using PFGE by SmaI-digestion. It was shown that the resistant markers G and T got transferred from clinical S. aureus (JS-105 to carrier S. aureus (JN-49

Methicillin-Resistant Staphylococcus aureus from Brazilian Dairy Farms and Identification of Novel Sequence Types.

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Oliveira, C J B; Tiao, N; de Sousa, F G C; de Moura, J F P; Santos Filho, L; Gebreyes, W A

2016-03-01

The aim of this study was to investigate the phenotypic and genotypic diversity and anti-microbial resistance among staphylococci of dairy herds that originated from Paraiba State, north-eastern Brazil, a region where such studies are rare. Milk samples (n = 552) were collected from 15 dairy farms. Isolates were evaluated for anti-microbial susceptibility by Kirby-Bauer disc diffusion method. Confirmation of methicillin-resistant Staphylococcus aureus (MRSA) was performed using multiplex PCR targeting mecA and nuc genes in addition to phenotypic assay based on PBP-2a latex agglutination. Clonal relatedness of isolates was determined by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) genotyping. Staphylococci were detected in 269 (49%) of the samples. Among these, 65 (24%) were S. aureus. The remaining 204 isolates were either coagulase-negative staphylococci (n = 188; 70%) or coagulase positive other than S. aureus (n = 16; 6%). Staphylococci were cultured in seven (35%) of the 20 hand swab samples, from which five isolates were S. aureus. The isolates were most commonly resistant against penicillin (43%), ampicillin (38%) and oxacillin (27%). The gene mecA was detected in 21 S. aureus from milk and in one isolate from a milker's hand. None of the isolates were resistant to vancomycin. PFGE findings showed high clonal diversity among the isolates. Based on MLST, we identified a total of 11 different sequence types (STs 1, 5, 6, 83, 97, 126, 1583, 1622, 1623, 1624 and 1625) with four novel STs (ST1622-ST1625). The findings show that MRSA is prevalent in milk from semi-extensive dairy cows in north-eastern Brazil, and further investigation on its extent in various types of milk production systems and the farm-to-table continuum is warranted. © 2015 Blackwell Verlag GmbH.

Microbiological study of therapeutic soft contact lenses used in the treatment of recurrent corneal erosion syndrome.

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Park, Young Min; Kwon, Han Jo; Lee, Jong Soo

2015-03-01

To determine the bacteriological spectrum of the removed therapeutic soft contact lenses (TSCLs) and to establish efficacy of prophylactic antibiotics on TSCLs used for 2 weeks for treatment of patients with recurrent corneal erosion syndrome (RCES). This study included idiopathic RCES treated using highly oxygen-permeable silicone hydrogel contact lenses (CLs), and treated 4 times per day with topical tobramycin 3% for 2 weeks. After TSCLs were applied for 2 weeks, the lenses were removed with sterile forceps under which a speculum was inserted, and placed on blood agar with the inner face down. The TSCLs were analyzed for bacterial colonization, and antibiotic susceptibility tests were performed for the isolates, using disk diffusion. Of the 40 lenses analyzed, 9 (22.5%) yielded positive cultures. Staphylococcus epidermidis was the most commonly isolated microorganism; there were five methicillin-sensitive coagulase-negative staphylococci and two methicillin-resistant coagulase-negative staphylococci. Furthermore, we found two lenses that were colonized by Enterobacter gergoviae and Citrobacter freundii. All cultured bacteria showed intermediate or complete sensitivity to ciprofloxacin, tigecycline, and tobramycin. Despite bacterial colonization in 9 CLs, no clinical signs of infectious keratitis were found in any of the patients with prophylactic topical tobramycin 3%. In case of using TSCLs for 2 weeks, tobramycin or ciprofloxacin may be useful as prophylactic topical antibiotics for preventing secondary corneal infections. Considering currently growing incidence of ciprofloxacin-resistant ocular isolates, tobramycin seems to be a reasonable prophylactic topical antibiotic susceptible broad spectrum of bacteria in clinics.

Synovial fluid multiplex PCR is superior to culture for detection of low-virulent pathogens causing periprosthetic joint infection.

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Morgenstern, Christian; Cabric, Sabrina; Perka, Carsten; Trampuz, Andrej; Renz, Nora

2018-02-01

Analysis of joint aspirate is the standard preoperative investigation for diagnosis of periprosthetic joint infection (PJI). We compared the diagnostic performance of culture and multiplex polymerase chain reaction (PCR) of synovial fluid for diagnosis of PJI. Patients in whom aspiration of the prosthetic hip or knee joint was performed before revision arthroplasty were prospectively included. The performance of synovial fluid culture and multiplex PCR was compared by McNemar's chi-squared test. A total of 142 patients were included, 82 with knee and 60 with hip prosthesis. PJI was diagnosed in 77 patients (54%) and aseptic failure in 65 patients (46%). The sensitivity of synovial fluid culture and PCR was 52% and 60%, respectively, showing concordant results in 116 patients (82%). In patients with PJI, PCR missed 6 high-virulent pathogens (S. aureus, streptococci, E. faecalis, E. coli) which grew in synovial fluid culture, whereas synovial fluid culture missed 12 pathogens detected by multiplex PCR, predominantly low-virulent pathogens (Cutibacterium acnes and coagulase-negative staphylococci). In patients with aseptic failure, PCR detected 6 low-virulent organisms (predominantly C. acnes). While the overall performance of synovial fluid PCR was comparable to culture, PCR was superior for detection of low-virulent bacteria such as Cutibacterium spp. and coagulase-negative staphylococci. In addition, synovial fluid culture required several days for growth, whereas multiplex PCR provided results within 5hours in an automated manner. Copyright © 2017 Elsevier Inc. All rights reserved.

Microbiological and molecular characterization of human clinical isolates of Staphylococcus cohnii, Staphylococcus hominis, and Staphylococcus sciuri.

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Garza-González, Elvira; Morfin-Otero, Rayo; Martínez-Vázquez, Manuel A; Gonzalez-Diaz, Esteban; González-Santiago, Omar; Rodríguez-Noriega, Eduardo

2011-12-01

The incidence of coagulase-negative staphylococci reported as causative agents of nosocomial infections has risen in the last decade. The aim of this study was to characterize biofilm formation, antibiotic resistance, SCCmec type, and genetic relatedness in clinical isolates of Staphylococcus cohnii, Staphylococcus hominis, and Staphylococcus sciuri recovered from humans. Clinically relevant isolates of S. cohnii (n = 15), S. hominis (n = 9), and S. sciuri (n = 6), were collected from patients. Biofilm formation was evaluated using crystal violet staining, drug susceptibility was assessed using the broth microdilution method, and methicillin resistance was measured using the cefoxitin disk test. SCCmec was typed using 2 different methodologies, and genetic relatedness was determined by pulsed-field gel electrophoresis (PFGE). Sixty percent (9/15) of S. cohnii, 33% (3/9) of S. hominis, and 50% (3/6) of S. sciuri isolates were categorized as weak producers of biofilm. None of the isolates were resistant to vancomycin or linezolid. All 3 species showed a high resistance (> 66%) to ampicillin, levofloxacin, erythromycin, and ceftriaxone, and the majority of the isolates were methicillin-resistant. PFGE revealed that the S. cohnii isolates comprised 1 dominant clone. The S. cohnii, S. hominis, and S. sciuri isolates analyzed in this study showed a high methicillin resistance and resistance to other antimicrobials. The results of this study strongly suggest that coagulase-negative staphylococci harbour new SCCmec elements. We report the first case of a clone of S. cohnii associated with human disease.

21 CFR 524.1044h - Gentamicin sulfate, mometasone furoate, clotrimazole otic suspension.

Science.gov (United States)

2010-04-01

... (Pseudomonas spp. [including P. aeruginosa], coagulase-positive staphylococci, Enterococcus faecalis, Proteus mirabilis, and beta-hemolytic streptococci). [66 FR 712, Jan. 4, 2001, as amended at 68 FR 15370, Mar. 31...

LAB Bacteriocins Controlling the Food Isolated (Drug-Resistant Staphylococci

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Jesús Perales-Adán

2018-06-01

Full Text Available Staphylococci are a group of microorganisms that can be often found in processed food and they might pose a risk for human health. In this study we have determined the content of staphylococci in 7 different fresh goat-milk cheeses. These bacteria were present in all of them, ranging from 103 to 106 CFU/g based on growth on selective media. Thus, a set of 97 colonies was randomly picked for phenotypic and genotypic identification. They could be clustered by RAPD-PCR in 10 genotypes, which were assigned by 16S rDNA sequencing to four Staphylococcus species: Staphylococcus aureus, Staphylococcus chromogenes, S. simulans, and S. xylosus. Representative strains of these species (n = 25 were tested for antibiotic sensitivity, and 11 of them were resistant to at least one of the antibiotics tested, including erythromycin, amoxicillin-clavulanic acid and oxacillin. We also tested two bacteriocins produced by lactic acid bacteria (LAB, namely the circular bacteriocin AS-48 and the lantibiotic nisin. These peptides have different mechanism of action at the membrane level. Nevertheless, both were able to inhibit staphylococci growth at low concentrations ranging between 0.16–0.73 μM for AS-48 and 0.02–0.23 μM for nisin, including the strains that displayed antibiotic resistance. The combined effect of these bacteriocins were tested and the fractional inhibitory concentration index (FICI was calculated. Remarkably, upon combination, they were active at the low micromolar range with a significant reduction of the minimal inhibitory concentration. Our data confirms synergistic effect, either total or partial, between AS-48 and nisin for the control of staphylococci and including antibiotic resistant strains. Collectively, these results indicate that the combined use of AS-48 and nisin could help controlling (pathogenic staphylococci in food processing and preventing antibiotic-resistant strains reaching the consumer in the final products.

Community-acquired pneumonia due to Staphylococcus cohnii in an HIV-infected patient: case report and review.

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Mastroianni, A; Coronado, O; Nanetti, A; Manfredi, R; Chiodo, F

1995-10-01

Coagulase-negative staphylococci recently have been implicated as a cause of serious infections in immunocompromised individuals. An unusual case of community-acquired pneumonia due to Staphylococcus cohnii in an HIV-infected drug user is described. Results of a study conducted to examine the prevalence of infection due to Staphylococcus cohnii strains and their antibiotic-sensitivity patterns show a low frequency but a high morbidity. These results and a brief review of the literature emphasize the importance of these organisms and other staphylococcal species as emerging opportunistic pathogens in patients with AIDS.

Antimicrobial efficacy of preoperative skin antisepsis and clonal relationship to postantiseptic skin-and-wound flora in patients undergoing clean orthopedic surgery.

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Daeschlein, G; Napp, M; Layer, F; von Podewils, S; Haase, H; Spitzmueller, R; Assadian, O; Kasch, R; Werner, G; Jünger, M; Hinz, P; Ekkernkamp, A

2015-11-01

Nosocomial surgical site infections (SSI) are still important complications in surgery. The underlying mechanisms are not fully understood. The aim of this study was to elucidate the possible role of skin flora surviving preoperative antisepsis as a possible cause of SSI. We conducted a two-phase prospective clinical trial in patients undergoing clean orthopedic surgery at a university trauma center in northern Germany. Quantitative swab samples were taken from pre- and postantiseptic skin and, additionally, from the wound base, wound margin, and the suture of 137 patients. Seventy-four patients during phase I and 63 during phase II were investigated. Microbial growth, species spectrum, and antibiotic susceptibility were analyzed. In phase two, the clonal relationship of strains was additionally analyzed. 18.0 % of the swab samples were positive for bacterial growth in the wound base, 24.5 % in the margin, and 27.3 % in the suture. Only 65.5 % of patients showed a 100 % reduction of the skin flora after antisepsis. The microbial spectrum in all postantiseptic samples was dominated by coagulase-negative staphylococci (CoNS). Clonally related staphylococci were detected in ten patients [nine CoNS, one methicillin-susceptible Staphylococcus aureus (MSSA)]. Six of ten patients were suspected of having transmitted identical clones from skin flora into the wound. Ethanol-based antisepsis results in unexpected high levels of skin flora, which can be transmitted into the wound during surgery causing yet unexplained SSI. Keeping with the concept of zero tolerance, further studies are needed in order to understand the origin of this flora to allow further reduction of SSI.

From Clinical Microbiology to Infection Pathogenesis: How Daring To Be Different Works for Staphylococcus lugdunensis

Science.gov (United States)

Frank, Kristi L.; del Pozo, José Luis; Patel, Robin

2008-01-01

Staphylococcus lugdunensis has gained recognition as an atypically virulent pathogen with a unique microbiological and clinical profile. S. lugdunensis is coagulase negative due to the lack of production of secreted coagulase, but a membrane-bound form of the enzyme present in some isolates can result in misidentification of the organism as Staphylococcus aureus in the clinical microbiology laboratory. S. lugdunensis is a skin commensal and an infrequent pathogen compared to S. aureus and S. epidermidis, but clinically, infections caused by this organism resemble those caused by S. aureus rather than those caused by other coagulase-negative staphylococci. S. lugdunensis can cause acute and highly destructive cases of native valve endocarditis that often require surgical treatment in addition to antimicrobial therapy. Other types of S. lugdunensis infections include abscess and wound infection, urinary tract infection, and infection of intravascular catheters and other implanted medical devices. S. lugdunensis is generally susceptible to antimicrobial agents and shares CLSI antimicrobial susceptibility breakpoints with S. aureus. Virulence factors contributing to this organism's heightened pathogenicity remain largely unknown. Those characterized to date suggest that the organism has the ability to bind to and interact with host cells and to form biofilms on host tissues or prosthetic surfaces. PMID:18202439

The diversity of antimicrobial resistance genes among staphylococci of animal origin.

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Wendlandt, Sarah; Feßler, Andrea T; Monecke, Stefan; Ehricht, Ralf; Schwarz, Stefan; Kadlec, Kristina

2013-08-01

Staphylococci of animal origin harbor a wide variety of resistance genes. So far, more than 40 different resistance genes have been identified in staphylococci from animals. This includes genes that confer resistance to virtually all classes of antimicrobial agents approved for use in animals, such as penicillins, cephalosporins, tetracyclines, macrolides, lincosamides, phenicols, aminoglycosides, aminocyclitols, pleuromutilins, and diaminopyrimidines. The gene products of some of these resistance genes confer resistance to only specific members of a class of antimicrobial agents, whereas others confer resistance to the entire class or even to members of different classes of antimicrobial agents. The resistance mechanisms specified by the resistance genes fall into three major categories: (i) enzymatic inactivation, (ii) active efflux, or (iii) protection/modification/replacement of the cellular target sites of the antimicrobial agents. Mobile genetic elements, in particular plasmids and transposons, play a major role as carriers of antimicrobial resistance genes in animal staphylococci. They facilitate the exchange of resistance genes with staphylococci of human origin but also with other Gram-positive bacteria. Copyright © 2013 Elsevier GmbH. All rights reserved.

Methicillin-resistant Staphylococci in companion animals

DEFF Research Database (Denmark)

Baptiste, Keith Edward; Williams, Kerry; Williams, Nicola J.

2005-01-01

We determined the molecular characteristics of methicillin-resistant staphylococci from animals and staff at a small animal and equine hospital. Methicillin-restistant Staphylococcus aureus identical to human EMRSA-15 was found in dogs and hospitalstaff. In contrast, 5 distinct MRSA strains were...

Cationic compounds with activity against multidrug-resistant bacteria: interest of a new compound compared with two older antiseptics, hexamidine and chlorhexidine.

Science.gov (United States)

Grare, M; Dibama, H Massimba; Lafosse, S; Ribon, A; Mourer, M; Regnouf-de-Vains, J-B; Finance, C; Duval, R E

2010-05-01

Use of antiseptics and disinfectants is essential in infection control practices in hospital and other healthcare settings. In this study, the in vitro activity of a new promising compound, para-guanidinoethylcalix[4]arene (Cx1), has been evaluated in comparison with hexamidine (HX) and chlorhexidine (CHX), two older cationic antiseptics. The MICs for 69 clinical isolates comprising methicillin-resistant Staphylococcus aureus, methicillin-sensitive S. aureus, coagulase-negative staphylococci (CoNS) (with or without mecA), vancomycin-resistant enterococci, Enterobacteriaceae producing various beta-lactamases and non-fermenting bacilli (Pseudomonas aeruginosa, Acinetobacter baumanii, Stenotrophomonas maltophilia) were determined. Cx1 showed similar activity against S. aureus, CoNS and Enterococcus spp., irrespective of the presence of mecA or van genes, or associated resistance genes, with very good activity against CoNS (MIC compound against all strains, with broad-spectrum and conserved activity against multidrug-resistant strains. HX showed a lower activity, essentially against Gram-positive strains. Consequently, the differences observed with respect to Cx1 suggest that they are certainly not the consequence of antibiotic resistance phenotypes, but rather the result of membrane composition modifications (e.g. of lipopolysaccharide), or of the presence of (activated) efflux-pumps. These results raise the possibility that Cx1 may be a potent new antibacterial agent of somewhat lower activity but significantly lower toxicity than CHX.

Comparison of 'time to detection' values between BacT/ALERT VIRTUO and BacT/ALERT 3D instruments for clinical blood culture samples.

Science.gov (United States)

Congestrì, Francesco; Pedna, Maria Federica; Fantini, Michela; Samuelli, Michela; Schiavone, Pasqua; Torri, Arianna; Bertini, Stefania; Sambri, Vittorio

2017-09-01

The early detection of bacteraemia and fungemia is of paramount importance to guide antimicrobial therapy in septic patients. In this study the 'time to detection' (TTD) value for the new blood culture system BacT/ALERT VIRTUO (VIRTUO) was evaluated in 1462 positive clinical bottles and compared with the TTD for 1601 positive clinical bottles incubated in the BacT/ALERT 3D system (BTA-3D). The most representative microorganisms isolated from bottles incubated in both blood culture systems were divided into eight categories (in order of frequency): coagulase-negative staphylococci (CoNS), Escherichia coli, Enterobacteriaceae (other than E. coli), Staphylococcus aureus, Enterococcus spp, viridans group streptococci, Pseudomonas aeruginosa, and Candida spp. The comparison of TTD values for the two blood culture systems strongly indicated that growth of the first five groups listed above was detected earlier with VIRTUO than with BTA-3D (p culture system can reduce the TTD for more than 75% of isolated microorganisms. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Use of genotypic identification by sodA sequencing in a prospective study to examine the distribution of coagulase-negative Staphylococcus species among strains recovered during septic orthopedic surgery and evaluate their significance.

Science.gov (United States)

Sivadon, V; Rottman, M; Chaverot, S; Quincampoix, J-C; Avettand, V; de Mazancourt, P; Bernard, L; Trieu-Cuot, P; Féron, J-M; Lortat-Jacob, A; Piriou, P; Judet, T; Gaillard, J-L

2005-06-01

A total of 212 coagulase-negative Staphylococcus strains recovered prospectively during 119 surgeries for proven or suspected bone and joint infection (BJI) were identified by sodA sequencing. These strains were identified as 151 Staphylococcus epidermidis isolates, 15 S. warneri isolates, 14 S. capitis isolates, 9 S. hominis isolates, 6 S. lugdunensis isolates, 5 S. haemolyticus isolates, 4 S. caprae isolates, 4 S. pasteuri isolates, 3 S. simulans isolates, and 1 S. cohnii isolate. Only S. epidermidis, S. lugdunensis, S. capitis, and S. caprae were found to be infecting organisms and were involved, respectively, in 35 (81.4%), 3 (7.0%), 3 (7.0%), and 2 (4.6%) cases of BJI.

High prevalence of Staphylococcus haemolyticus and Staphylococcus saprophyticus in environmental samples of a Tunisian hospital.

Science.gov (United States)

Dziri, Raoudha; Klibi, Naouel; Lozano, Carmen; Ben Said, Leila; Bellaaj, Ridha; Tenorio, Carmen; Boudabous, Abdellatif; Ben Slama, Karim; Torres, Carmen

2016-06-01

The purpose of this study was to evaluate the rate of detection of coagulase negative staphylococci (CoNS) in environmental samples of 17 services in a Tunisian hospital, determining the antimicrobial resistance phenotypes and genotypes of recovered isolates. To our knowledge, this is the first study that determines the prevalence of CoNS with correlation of antibiotic resistance in the hospital environment in Tunisia. CoNS were obtained from 83 of the 200 tested samples (41.5%). Staphylococcus haemolyticus was the most prevalent species (45.8%), followed by S. saprophyticus (36.1%). The remaining CoNS species detected were S. epidermidis, S. cohnii, S. warneri, S. sciuri, S. simulans, S. pasteuri, S. arlettae, and S. xilosus. Methicillin-resistant CoNS were detected in 20 of the 200 tested samples (10%), and the mecA gene was demonstrated in 18 S. haemolyticus, one S. epidermidis and one S. saprophyticus isolates. Methicillin susceptible isolates were detected in 63 samples (31.5%). Antimicrobial resistance genes detected were as follows (number of isolates): erythromycin [msr(A) (n = 32); erm(C) (n = 8)], tetracycline [tet(K) and/or tet(M) (n = 21)], gentamicin [aac(6')-Ie-aph(2″)-Ia (n = 16)], kanamycin [(aph(3')-IIIa (n = 19)], tobramycin [ant(4')-Ia (n = 14)], and streptomycin [ant(6')-Ia (n = 3)]. The high frequency of detection of multi-drug-resistant CoNS in the hospital environment, especially S. haemolyticus and S. saprophyticus, is of relevance and could be due to cross-transmission between patients, staff, and environment. Copyright © 2016 Elsevier Inc. All rights reserved.

Characterization of staphylococci and their role in pathology of children

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M. A. Harуfulina

2014-03-01

Full Text Available The problem of human staphylococcal infection in the world has been considered. It is known that there are 27 species of staphylococci, 14 of them colonize the skin and mucous membranes of humans, and 3 of them may cause diseases. They are Staphylococcus aureus, S. epidermidis and S. saprophyticus. Staphylococci are causative agents of the large part of community-acquired and nosocomial bacteremia, pneumonia, infections of skin and soft tissues, bones and joints. Of all cases of nosocomial infections, S. aureus accounts for 31%. During the identification of 65 strains of bacteria isolated from people with respiratory tract lesions, it was found that 58.5% of cases were connected with presence of staphylococci. 86.8% of isolates identified belong to species S. aureus and 13.2% to S. saprophyticus. Study of pathogenicity factors manifestation revealed that all strains identified as S. aureus had plasmocoagulase; lipase and lecitinase were simultaneously detected in 78.3% of them, among S. saprophyticus strains in 20%. Presence of haemolysins was determined for 82.1% of strains of staphylococci. Ability to film formation was detected in 21 (63.6% strains of S. aureus and 2 (40% of S. saprophyticus strains. Given high frequency of carriers of staphylococci among healthy individuals, they should be considered as potentially pathogenic microorganisms and opportunistic pathogens. Due to their pathogenicity factors (adhesins, capsule, cell wall components, enzymes and toxins, staphylococci may cause diseases such as sepsis, meningitis, peritonitis, endocarditis, pneumonia, tonsillitis, and in young children they may result in serious Ritter illness (“babies scalded syndrome”, foodstuff infection and staphylococcal enterocolitis, in lactating women – mastitis, toxic shock syndrome. To solve the problem of staphylococcal infection prevention, it is necessary to use the following prophylaxis methods: to avoid decrease in immunity, to observe the

Bacterial Contamination of Iranian Paper Currency and Their Antibiotic Resistance Patterns

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Farzaneh Firoozeh

2017-11-01

Full Text Available Background: Paper currency is used in exchange for services, and thisis why the circulation of paper currency from person to person expandsmicroorganisms. Objectives:: Paper banknotes would be a vector for transmission of pathogenic microorganisms through handling. This study aimed to determine bacterial contamination of Iranian paper currencies in circulation and their antibiotic resistance patterns. Materials and Methods: In this study, 337 currency notes of different value were collected from markets, shops, restaurants, bus stations and banks in Kashan, Iran during April 2015 to March 2016. The currency notes transferred to microbiology laboratory and were tested for bacterial contamination using standard microbiological methods. Antibiotic resistance patterns of isolated bacteria were determined by disk diffusion method according to CLSI standards. The results and data were analyzed using descriptive statistics. Results: Of 337 currency notes, 262 (77.7% were identified with bacterial contamination. Bacteria isolated from currency notes were as follows: Bacillus spp 113 (43.1%, coagulase-negative Staphylococci 99 (37.7%, Escherichia coli 20 (7.6%, Enterococci species 14 (5.3%, Staphylococcus aureus 8 (3.1%, Klebsiella spp 4 (1.5%, Shigella species 2 (0.8%, Pseudomonas species 2 (0.8%. The most and least contaminated currency notes were 50000 and 500 Rials, respectively. The most resistance rates in gram negative rods were against nalidixicacid, and ampicillin. Also most resistance rates in Staphylococcus aureus, coagulase-negative Staphylococci and Enterococci species were against ampicillin, erythromycin and tetracycline. Conclusion: Our study revealed that the bacterial contamination among Iranian paper currency in circulation especially those obtained from certain sources including shops and bus stations is high and in most cases these bacterial isolates are antibiotic resistant strains.

Incidence rate of clinical mastitis on Canadian dairy farms.

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Olde Riekerink, R G M; Barkema, H W; Kelton, D F; Scholl, D T

2008-04-01

No nationwide studies of the incidence rate of clinical mastitis (IRCM) have been conducted in Canada. Because the IRCM and distribution of mastitis-causing bacteria may show substantial geographic variation, the primary objective of this study was to determine regional pathogen-specific IRCM on Canadian dairy farms. Additionally, the association of pathogen-specific IRCM with bulk milk somatic cell count (BMSCC) and barn type were determined. In total, 106 dairy farms in 10 provinces of Canada participated in the study for a period of 1 yr. Participating producers recorded 3,149 cases of clinical mastitis. The most frequently isolated mastitis pathogens were Staphylococcus aureus, Escherichia coli, Streptococcus uberis, and coagulase-negative staphylococci. Overall mean and median IRCM were 23.0 and 16.7 cases per 100 cow-years in the selected herds, respectively, with a range from 0.7 to 97.4 per herd. No association between BMSCC and overall IRCM was found, but E. coli and culture-negative IRCM were highest and Staph. aureus IRCM was lowest in low and medium BMSCC herds. Staphylococcus aureus, Strep. uberis, and Streptococcus dysgalactiae IRCM were lowest in the Western provinces. Staphylococcus aureus and Strep. dysgalactiae IRCM were highest in Québec. Cows in tie-stalls had higher incidences of Staph. aureus, Strep. uberis, coagulase-negative staphylococci, and other streptococcal IRCM compared with those in free-stalls, whereas cows in free stalls had higher Klebsiella spp. and E. coli IRCM than those in tie-stall barns. The focus of mastitis prevention and control programs should differ between regions and should be tailored to farms based on housing type and BMSCC.

Direct Identification and Antimicrobial Susceptibility Testing of Bacteria From Positive Blood Culture Bottles by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry and the Vitek 2 System.

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Jo, Sung Jin; Park, Kang Gyun; Han, Kyungja; Park, Dong Jin; Park, Yeon-Joon

2016-03-01

We evaluated the reliability and accuracy of the combined use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) bacterial identification and Vitek 2 antimicrobial susceptibility testing (AST) for bacteria from positive blood culture bottles. Direct identification and AST were performed in parallel to the standard methods in monomicrobial positive blood culture bottles. In total, 254 isolates grown on aerobic and/or anaerobic bottles were identified with MALDI-TOF Vitek MS (bioMérieux, France), and 1,978 microorganism/antimicrobial agent combinations were assessed. For isolates from anaerobic bottles, an aliquot of the culture broth was centrifuged, washed, and filtered through a nylon mesh. For isolates from aerobic/pediatric bottles, a lysis step using 9.26% ammonium chloride solution and 2% saponin solution was included. The overall correct identification rate was 81.8% (208/254) and that for gram-positive/gram-negative isolates was 73.9%/92.6%, respectively, and it was 81.8%, 87.6%, and 57.9% for isolates from aerobic, anaerobic, and pediatric bottles, respectively. Identification was not possible in 45 cases, and most of these isolates were streptococci (N=14) and coagulase-negative staphylococci (N=11). Misidentification occurred only in one case. Compared with standard methods, direct AST showed 97.9% (1,936/1,978) agreement with very major error of 0.25%, major error of 0.05%, and minor error of 1.8%. This simple and cost-effective sample preparation method gives reliable results for the direct identification and AST of bacteria. For the identification of streptococci and coagulase-negative staphylococci, the method should be further improved.

The analysis of milk components and pathogenic bacteria isolated from bovine raw milk in Korea.

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Park, Y K; Koo, H C; Kim, S H; Hwang, S Y; Jung, W K; Kim, J M; Shin, S; Kim, R T; Park, Y H

2007-12-01

Bovine mastitis can be diagnosed by abnormalities in milk components and somatic cell count (SCC), as well as by clinical signs. We examined raw milk in Korea by analyzing SCC, milk urea nitrogen (MUN), and the percentages of milk components (milk fat, protein, and lactose). The associations between SCC or MUN and other milk components were investigated, as well as the relationships between the bacterial species isolated from milk. Somatic cell counts, MUN, and the percentages of milk fat, protein, and lactose were analyzed in 30,019 raw milk samples collected from 2003 to 2006. The regression coefficients of natural logarithmic-transformed SCC (SCCt) on milk fat (-0.0149), lactose (-0.8910), and MUN (-0.0096), and those of MUN on milk fat (-0.3125), protein (-0.8012), and SCCt (-0.0671) were negative, whereas the regression coefficient of SCCt on protein was positive (0.3023). When the data were categorized by the presence or absence of bacterial infection in raw milk, SCCt was negatively associated with milk fat (-0.0172), protein (-0.2693), and lactose (-0.4108). The SCCt values were significantly affected by bacterial species. In particular, 104 milk samples infected with Staphylococcus aureus had the highest SCCt (1.67) compared with milk containing other mastitis-causing bacteria: coagulase-negative staphylococci (n = 755, 1.50), coagulase-positive staphylococci (except Staphylococcus aureus; n = 77, 1.59), Streptococcus spp. (Streptococcus dysgalactiae, n = 37; Streptococcus uberis, n = 12, 0.83), Enterococcus spp. (n = 46, 1.04), Escherichia coli (n = 705, 1.56), Pseudomonas spp. (n = 456, 1.59), and yeast (n = 189, 1.52). These results show that high SCC and MUN negatively affect milk components and that a statistical approach associating SCC, MUN, and milk components by bacterial infection can explain the patterns among them. Bacterial species present in raw milk are an important influence on SCC in Korea.

[New container of sample: role in the reduction of bacterial contamination of standard platelet units].

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Fehri, S; Tazi, I; Loukhmass, L; Benchemsi, N

2006-12-01

Bacterial contamination of unstable blood products constitutes today the most frequent infectious risk transmitted by blood transfusion. Platelet concentrates are often incrimineted. As responsible germs are in general of cutaneous origin, a sample procedure with diversion of the first 20 ml during blood donation is studied. The aim of this study is to evaluate the results of this technique on bacterial contamination rate of standard platelet units prepared at the regional blood transfusion center in Casablanca. A comparative study of two types of sample pockets is made: 500 Standard Platelet concentrates (CPS) are prepared after collection using standard triple bags (Baxter) (group 1) and 560 pockets of CPS were prepared after collection using triple bags with Sample Diversion Pouch sampling system for elimination of the first 20 ml of donation (Macopharma and Terumo) (group 2). The skin was disinfected in two times with alcohol 70%. The bacteriological study was made in the two groups at the third day of conservation. Six CPS of group 1 were contaminated, of which five were staphylococci coagulase negative and one bacillus sp. Six CPS of group 2 were contaminated, of which five were staphylococci coagulase negative and one staphylococcus aureus. The bacteria isolated were those of cutaneous flora at 100%. Diversion of first 20 ml of blood donation results in a 16.6% reduction in bacterial contamination of CPS (P>0.05). The non-significant reduction in the prevalence of the bacterial infection of CP formulates the problem of the indication of the sampling devices with derivation of first 20 ml during blood collection.

Nasal Carriage of 200 Patients with Nasal Bone Fracture in Korea

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Jun Wook Lee

2013-09-01

Full Text Available Background Pathogens in the nasal cavity during nasal surgery could lead to a systemicinfectious condition, such as bacteremia, nosocomial infection, or toxic shock syndrome.However, there is no research about the prevalence of nasal carriage in patients with nasalbone fracture.Methods This was a prospective, double-blind, randomized study about the rate of nasalcarriage in 200 patients with nasal bone fracture in Korea. Nasal secretions were taken fromboth the middle nasal meatus and colonized. All analyses were carried out using SPSS software.Results Pathogens were identified in 178 of the 200 cases. Coagulase-negative staphylococci(CNS were the most cultured bacteria in 127 (66.84% of the 190 total patients after excluding10 cases of contaminated samples, and methicillin-resistant coagulase-negative staphylococci(MRCNS were found in 48 (25.26%. Staphylococcus aureus was the second mostidentified pathogen, found in 36 (18.95%, followed by 7 cases (3.68% of methicillin-resistantStaphylococcus aureus (MRSA. The prevalence rate of MRSA in the females was higher thanthat in the males (RR=4.70; 95% CI, 1.09-20.18, but other demographic factors had no effecton the prevalence rate of MRSA and MRCNS.Conclusions The prevalence rate of these pathogens in patients with nasal bone fracture inKorea was similar to other reports. However, few studies have addressed the prevalence rateof CNS and MRCNS in accordance with risk factors or the change in prevalence according tospecific prophylaxis against infectious complications. Additional research is needed on thepotential connections between clinical factors and microbiological data.

Central venous catheter-related bloodstream infections in cancer patients

International Nuclear Information System (INIS)

Butt, T.; Afzal, R.K.; Ahmad, R.N.; Hussain, I.; Anwar, M.

2004-01-01

Objective: To determine the frequency of central venous catheter-related bloodstream infections (CR-BSI) in cancer patients and the antimicrobial susceptibility pattern of the isolates. Subjects and Methods: Cancer patients requiring short or long-term central venous catheterization at the time of admission or thereafter were included. Catheter tips on removal were cultured quantitatively; specimens of blood and pus were cultured qualitatively. Isolates were identified and antimicrobial susceptibility testing was performed by standard techniques. Results: Eighty-nine patients were included in the study. The frequency of CR-BSI was 17%. Out of the 19 organisms isolated, 10 (53%) were Gram-positive cocci, 8 (42%) were Gram-negative rods and 1 (5%) was a fungus. Coagulase negative staphylococci (27%) were the predominant pathogens. Among the staphylococci, 46% of the isolates were methicillin-resistant. All Gram-positive isolates were susceptive to glycopeptides. Gram-negative rods were resistant to most of the commonly used antimicrobial groups. Conclusion: Central venous catheter is an important source of bloodstream infections in cancer patients. Most of the infections are caused by Gram-positive cocci. Rigorous infection control measures and continuous surveillance is required to curb the frequency of these infections. (author)

Microbiological Quality of Raw Goat Milk in Bogor, Indonesia

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E. Taufik

2011-08-01

Full Text Available Milk samples were investigated for counts and prevalence of indicator bacteria, which were TPC, coliforms, coagulase positive Staphylococci (CPS, and coagulase negative Staphylococci (CNS. Ten potential risk factors were also evaluated in relation to the prevalence of indicator bacteria. The results showed that the median values of indicator bacterial counts from overall udder-half milk samples were 3.74, 0.70, 1.70, and 2.52 log cfu/ml and from bulk milk samples were 5.69, 2.98, 3.66 and 3.32 log cfu/ml for TPC, coliforms, CPS, and CNS, respectively. None of the median values of overall udder-half milk samples exceeded the maximum limit of the standards for all indicator bacteria. However, in the bulk milk samples only the median value of TPC below the maximum limit of the standards. Overall prevalence of coliforms, CPS and CNS from udder-half milk samples were 46.3%, 37.7%, and 66.0%, respectively, and from bulk milk samples were 86.7%, 76.7%, and 86.7%, respectively. Saanen crossbreed, fifth parity and udders with inflammation were found to be risk factors. This study results indicated that the hygienic practices in the dairy goat farms are still need to be increased. To increase the hygienic level of the milk, the identified significant risk factors must be controlled.

Two Distinct Coagulase-Dependent Barriers Protect Staphylococcus aureus from Neutrophils in a Three Dimensional in vitro Infection Model

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Guggenberger, Christoph; Wolz, Christiane; Morrissey, Julie A.; Heesemann, Jürgen

2012-01-01

Staphylococcus aureus is a pyogenic abscess-forming facultative pathogenic microorganism expressing a large set of virulence-associated factors. Among these, secreted proteins with binding capacity to plasma proteins (e.g. fibrinogen binding proteins Eap and Emp) and prothrombin activators such as Coagulase (Coa) and vWbp are involved in abscess formation. By using a three-dimensional collagen gel (3D-CoG) supplemented with fibrinogen (Fib) we studied the growth behavior of S. aureus strain Newman and a set of mutants as well as their interaction with mouse neutrophils by real-time confocal microscopy. In 3D-CoG/Fib, S. aureus forms microcolonies which are surrounded by an inner pseudocapsule and an extended outer dense microcolony-associated meshwork (MAM) containing fibrin. Coa is involved in formation of the pseudocapsule whereas MAM formation depends on vWbp. Moreover, agr-dependent dispersal of late stage microcolonies could be observed. Furthermore, we demonstrate that the pseudocapsule and the MAM act as mechanical barriers against neutrophils attracted to the microcolony. The thrombin inhibitor argatroban is able to prevent formation of both pseudocapsule and MAM and supports access of neutrophils to staphylococci. Taken together, this model can simulate specific stages of S. aureus abscess formation by temporal dissection of bacterial growth and recruitment of immune cells. It can complement established animal infection models in the development of new treatment options. PMID:22253592

Prevalence of coagulase gene polymorphism in Staphylococcus aureus isolates causing bovine mastitis

DEFF Research Database (Denmark)

Aarestrup, Frank Møller; Dangler, C. A.; Sordillo, L. M.

1995-01-01

This study was conducted to investigate polymorphism of the coagulase gene of Staphylococcus aureus causing bovine mastitis. One hundred eighty-seven strains of S. aureus were isolated from bovine mastitic milk samples obtained from 187 different Danish dairy farms. The isolates were characterised......% of the isolates. The ease of analysing coagulase gene polymorphisms among a large number of strains, and the multiple distinct polymorphic patterns generated, supports the use of this technique in epidemiological investigations of bovine mastitis. The predominating variants may have predelection for causing...

Molecular Typing and Antimicrobial Susceptibility of Methicillin-Resistant Staphylococcus aureus Isolated from Bovine Milk in Tanzania.

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Mohammed, Jibril; Ziwa, Michael Henry; Hounmanou, Yaovi Mahuton Gildas; Kisanga, Adela; Tuntufye, Huruma Nelwike

2018-01-01

Methicillin-resistant Staphylococcus aureus (MRSA) in raw milk can be transmitted from animals to humans, and in Tanzania raw milk is sold in local markets and consumed as purchased. This study was performed to determine the molecular characteristics and antimicrobial susceptibility pattern of MRSA strains isolated from raw bovine milk sold at local markets in Tanzania. A total of 117 raw milk samples were cultured on Baird-Parker medium to isolate S. aureus and PCR was used for amplification of gltB gene for S. aureus identification and the presence of mecA gene for methicillin-resistant strains. Coagulase-negative (CN) S. aureus were reconfirmed using tube coagulase, DNase, and API Staph tests. MRSA isolates were spa typed whereas antimicrobial susceptibility testing was performed by the disc diffusion method. Forty-six coagulase positives (CP) and two CN S. aureus were identified. Most strains were resistant to penicillin (72%), and 3 isolates: 2 CN S. aureus and 1 coagulase-negative Staphylococci (CNS), were phenotypically resistant to vancomycin, oxacillin, and cefoxitin and were confirmed to carry mecA. Resistance to clindamycin, trimethoprim-sulfamethoxazole, and tetracycline was 23.9%, 30.4%, and 41.3%, respectively. Twelve isolates exhibited multidrug resistance; however, only one mecA positive strain among the three was typeable and belonged to spa type t2603. This study reports for the first time the presence of CN variant of MRSA, which was assigned the spa type t2603, and the presence of multidrug resistant S. aureus isolates from bovine milk in Morogoro, Tanzania.

SadA-Expressing Staphylococci in the Human Gut Show Increased Cell Adherence and Internalization

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Arif Luqman

2018-01-01

Full Text Available Summary: A subgroup of biogenic amines, the so-called trace amines (TAs, are produced by mammals and bacteria and can act as neuromodulators. In the genus Staphylococcus, certain species are capable of producing TAs through the activity of staphylococcal aromatic amino acid decarboxylase (SadA. SadA decarboxylates aromatic amino acids to produce TAs, as well as dihydroxy phenylalanine and 5-hydroxytryptophan to thus produce the neurotransmitters dopamine and serotonin. SadA-expressing staphylococci were prevalent in the gut of most probands, where they are part of the human intestinal microflora. Furthermore, sadA-expressing staphylococci showed increased adherence to HT-29 cells and 2- to 3-fold increased internalization. Internalization and adherence was also increased in a sadA mutant in the presence of tryptamine. The α2-adrenergic receptor is required for enhanced adherence and internalization. Thus, staphylococci in the gut might contribute to gut activity and intestinal colonization. : Luqman et al. examine the sadA gene and argue that it contributes to TAs. They found that neuromodulator-producing staphylococci were present in the gut of most probands. The produced neuromodulators enhanced the adherence and internalization of staphylococci to cells in culture. Keywords: adherence, aromatic amino acid decarboxylase, gut microbiota, internalization, neuromodulator, neurotransmitter, staphylococcus

Prevalence and antibiotic resistance of Staphylococci isolated from ...

African Journals Online (AJOL)

, often causing therapeutic impasses. Our study was conducted at the Bacteriology Laboratory of Kolea (Tipaza, Algeria) Hospital. The aim of this study was to determine the prevalence of staphylococci in clinical purulent, sepsis and urinary ...

The role of breast milk in the colonization of neonatal gut and skin with coagulase-negative staphylococci.

Science.gov (United States)

Soeorg, Hiie; Metsvaht, Tuuli; Eelmäe, Imbi; Merila, Mirjam; Treumuth, Sirli; Huik, Kristi; Jürna-Ellam, Marika; Ilmoja, Mari-Liis; Lutsar, Irja

2017-11-01

BackgroundWe aimed to determine the genetic relatedness between Staphylococcus epidermidis colonizing breast milk (BM) and BM-fed neonates during the first month of life.MethodsS. epidermidis was isolated from the stool and skin swabs of 20 healthy term and 49 preterm neonates hospitalized in the neonatal intensive care unit and from the BM of mothers once a week and typed by multilocus variable-number tandem-repeat analysis. Virulence-related genes were determined by PCR.ResultsThe gut (95%) and skin (100%) of term neonates were colonized with strains genetically similar to those in BM and carrying mecA and IS256 at low rate (both skin (34.7%) and in the gut in the first week of life (14.3%), but the prevalence of mecA (>90.6%) and IS256 (>61.7%) was high. By the fourth week, in the gut of preterm neonates the prevalence of mecA (73.8%) and IS256 (18.4%) decreased, but colonization with strains genetically similar to those in BM increased (83.7%).ConclusionDuring early life, the skin and gut of preterm neonates is colonized with S. epidermidis that is distinct from strains found in BM, but gradually the gut is enriched with strains genetically similar to those in BM, as in term neonates.

In-vitro activity and beta-lactamase stability of methicillin, isoxazolyl penicillins and cephalothin against coagulase-negative staphylococci

DEFF Research Database (Denmark)

Jarløv, J O; Rosdahl, V T; Mortensen, I

1988-01-01

-level of the isoxazolyl penicillins showed a high degree of uniformity. However more strains were resistant to cloxacillin and oxacillin than to dicloxacillin and flucloxacillin. Only a weak correlation was found between beta-lactamase production, and resistance to the six antibiotics. Methicillin was the most stable...

Occurrence and characterization of Staphylococcus bacteria isolated from poultry in Western Poland.

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Marek, Agnieszka; Stepień-Pyśniak, Dagmara; Pyzik, Ewelina; Adaszek, Łukasz; Wilczyński, Jarosław; Winiarczyk, Stanisław

2016-01-01

In the pathology of poultry, infections caused by Staphylococcus spp. are taking on increasing significance. Although the Staphylococcus species most frequently isolated from these animals is Staphylococcus aureus, the literature data indicate that other species, both coagulase-positive and coagulase-negative, can also cause infections in birds. The aim of the study was to assess the frequency of occurrence of Staphylococcus infections in various poultry species in Western Poland and to test the susceptibility of isolated strains to selected antibiotics. The results obtained showed a relatively high rate of Staphylococcus infection in the poultry. From 2805 samples tested 302 strains (10.8%) of Staphylococcus were isolated. As many as 25 Staphylococcus species were distinguished among the strains isolated. S. cohnii (23.50%), S. aureus (15.89%) and S. lentus (13.90%) accounted for the highest percentages. Over half of the isolated staphylococci exhibited resistance to five of the antibiotics applied, with the highest percentage of resistant strains, 65%, noted for enrofloxacin.

In vitro mecA gene transfer among Staphylococcus aureus in ...

African Journals Online (AJOL)

AJL

2012-01-05

Jan 5, 2012 ... culture experiments, two types of the transconjugants were obtained. Transconjugants .... were brought together in coagulase-negative staphylo- cocci (CoNS) ..... pathogen to contagious bovine mastitis bacteria. PLoS ONE ...

Breastmilk donations: Bacteriological assessment, analysis of causes of non-compliance and suggestions for improvement.

Science.gov (United States)

Mullié, C; Obin, O; Outurquin, G; Grognet, S; Léké, A; Adjidé, C

2018-05-01

A total of 1099 breastmilk donations received by the milk bank at the Amiens University Hospital from January to June 2016 were assessed for bacteriological contamination according to French regulations. This consisted in enumerating the total aerobic flora before and after heat treatment as well as the specific enumeration of coagulase-positive staphylococci. Results above the mandatory limits for at least one of these parameters were found in 25.9% of the donations, resulting in the destruction of approximately one-quarter of the volume of the donations (∼195L). This is a huge loss in both economic and health-related terms for neonates, especially for pre-terms. To identify ways to improve the bacteriological assessment results and reduce the percentage of discarded milk, an analysis of the causes was conducted. The two main causes of non-compliance were the detection of a cultivable aerobic flora after heat treatment and the presence of coagulase-positive staphylococci above the mandatory limit (11.7% and 11.2% of the tested donations, respectively). Bacillus spp. were the leading cause of post-heat-treatment non-compliance. Therefore, the implementation of better environmental control could help reduce this kind of contamination. As for samples harboring coagulase-positive staphylococci, a further detection of toxins using molecular biology techniques could help discriminate actual health-hazardous donations that have to be destroyed while enabling the use of toxin-negative donations. Nevertheless, the economic viability of this proposal needs to be further assessed because these techniques are costly. Finally, a change in breastmilk dilutions used to enumerate the total aerobic flora to better reflect the actual level of these bacteria in the milk was proposed. Indeed, the comparison of various combinations of milk dilutions led to the conclusion that the association of the 1/10 and 1/100 dilutions was the best compromise between technical ease of

Evaluation of the synergistic potential of vancomycin combined with other antimicrobial agents against methicillin-resistant Staphylococcus aureus and coagulase-negative Staphylococcus spp strains

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Lívia Viganor da Silva

2011-02-01

Full Text Available Methicillin-resistant Staphylococcus aureus (MRSA and coagulase-negative Staphylococcus spp (CNS are the most common pathogens that cause serious long term infections in patients. Despite the existence of new antimicrobial agents, such as linezolid, vancomycin (VAN remains the standard therapy for the treatment of infections caused by these multidrug-resistant strains. However, the use of VAN has been associated with a high frequency of therapeutic failures in some clinical scenarios, mainly with decreasing concentration of VAN. This work aims to evaluate the synergic potential of VAN plus sulfamethoxazole/trimethoprim (SXT, VAN plus rifampin (RIF and VAN plus imipenem (IPM in sub-minimum inhibitory concentrations against 22 clinical strains of MRSA and CNS. The checkerboard method showed synergism of VAN/RIF and VAN/SXT against two and three of the 22 strains, respectively. The combination of VAN with IPM showed synergistic effects against 21 out of 22 strains by the E-test method. Four strains were analyzed by the time-kill curve method and synergistic activity was observed with VAN/SXT, VAN/RIF and especially VAN/IPM in sub-inhibitory concentrations. It would be interesting to determine if synergy occurs in vivo. Evidence of in vivo synergy could lead to a reduction of the standard VAN dosage or treatment time.

Isolation, Biochemical and Molecular Identification, and In-Vitro Antimicrobial Resistance Patterns of Bacteria Isolated from Bubaline Subclinical Mastitis in South India.

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P L Preethirani

Full Text Available Buffaloes are the second largest source of milk. Mastitis is a major impediment for milk production, but not much information is available about bubaline mastitis, especially subclinical mastitis. The aim of this study was to (a investigate the application of various tests for the diagnosis of bubaline subclinical mastitis, (b identify the major bacteria associated with it, and (c evaluate the antibiotic resistance pattern of the bacteria. To this end, 190 quarter milk samples were collected from 57 domesticated dairy buffaloes from organized (64 samples and unorganized (126 samples sectors. Of these, 48.4%, 40.0%, 45.8%, 61.1%, and 61.6% were positive for subclinical mastitis by somatic cell count, electrical conductivity, California mastitis test, bromothymol blue test, and N-acetyl glucosaminidase test, respectively. As compared to the gold standard of somatic cell count, California mastitis test performed the best. However, a combination of the two methods was found to be the best option. Microbiological evaluation, both by biochemical methods as well as by monoplex and multiplex polymerase chain reaction, revealed that coagulase-negative staphylococci were the most predominant (64.8% bacteria, followed by streptococci (18.1%, Escherichia coli (9.8% and Staphylococcus aureus (7.3%. Most of the pathogens were resistant to multiple antibiotics, especially to β-lactam antibiotics. We propose that California mastitis test be combined with somatic cell count for diagnosis of subclinical mastitis in domestic dairy buffaloes. Further, our results reveal high resistance of the associated bacteria to the β-lactam class of antibiotics, and a possible major role of coagulase-negative staphylococci in causing the disease in India.

Isolation, Biochemical and Molecular Identification, and In-Vitro Antimicrobial Resistance Patterns of Bacteria Isolated from Bubaline Subclinical Mastitis in South India.

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Preethirani, P L; Isloor, Shrikrishna; Sundareshan, S; Nuthanalakshmi, V; Deepthikiran, K; Sinha, Akhauri Y; Rathnamma, D; Nithin Prabhu, K; Sharada, R; Mukkur, Trilochan K; Hegde, Nagendra R

2015-01-01

Buffaloes are the second largest source of milk. Mastitis is a major impediment for milk production, but not much information is available about bubaline mastitis, especially subclinical mastitis. The aim of this study was to (a) investigate the application of various tests for the diagnosis of bubaline subclinical mastitis, (b) identify the major bacteria associated with it, and (c) evaluate the antibiotic resistance pattern of the bacteria. To this end, 190 quarter milk samples were collected from 57 domesticated dairy buffaloes from organized (64 samples) and unorganized (126 samples) sectors. Of these, 48.4%, 40.0%, 45.8%, 61.1%, and 61.6% were positive for subclinical mastitis by somatic cell count, electrical conductivity, California mastitis test, bromothymol blue test, and N-acetyl glucosaminidase test, respectively. As compared to the gold standard of somatic cell count, California mastitis test performed the best. However, a combination of the two methods was found to be the best option. Microbiological evaluation, both by biochemical methods as well as by monoplex and multiplex polymerase chain reaction, revealed that coagulase-negative staphylococci were the most predominant (64.8%) bacteria, followed by streptococci (18.1%), Escherichia coli (9.8%) and Staphylococcus aureus (7.3%). Most of the pathogens were resistant to multiple antibiotics, especially to β-lactam antibiotics. We propose that California mastitis test be combined with somatic cell count for diagnosis of subclinical mastitis in domestic dairy buffaloes. Further, our results reveal high resistance of the associated bacteria to the β-lactam class of antibiotics, and a possible major role of coagulase-negative staphylococci in causing the disease in India.

Effect of septoplasty and per-operative antibiotic prophylaxis on nasal flora.

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Karaman, E; Alimoglu, Y; Aygun, G; Kilic, E; Yagiz, C

2012-01-01

Septoplasty is one of the most commonly performed procedures in otolaryngology practice. Prophylactic use of antibiotics is controversial. Disruption of nasal flora may predispose individuals to infection. We investigated the effect of antibiotic prophylaxis and septoplasty on nasal flora. We included 115 consecutive patients who underwent septoplasty because of symptomatic nasal septal deviation. Patients were divided into study and control groups. Study patients received prophylactic parenteral sodium cefazoline twice a day beginning intra-operatively and while the nasal packing remained in the nose for 48 h, and expandable polyvinyl acetate (Merocel) packing covered with antibiotic ointment containing 0.2% nitrofurazone was inserted into each nostril at the end of the operation. Control patients received neither parenteral antibiotic prophylaxis nor antibiotic ointment around the Merocel packs. Both groups received oral prophylactic cefuroxime axetil for 5 d after nasal packing was removed. Nasal flora was determined pre-operatively, post-operatively when nasal packing was removed, and 3 mo after surgery. Study patients were compared to control patients at pack removal and 1 mo after surgery The effect of antibiotic use in septoplasty on nasal flora was as follows: Increased isolation rate of gram-positive rods (p = 0.007), decreased methicillin-sensitive coagulase-negative staphylococci (p = 0.002). Pre-operative and post-operative culture results at 3 mo were compared. The effect of septoplasty on nasal flora was as follows: Decreased coagulase-negative staphylococci (p = 0.05), decreased Klebsiella (p flora. Antibiotics do not protect against S. aureus colonization and contribute to a decrease in normal flora. Antibiotics do not seem to confer benefit in terms of flora changes. Studies investigating flora changes with a longer follow-up should be conducted.

Nasal Carriage of 200 Patients with Nasal Bone Fracture in Korea

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Jun Wook Lee

2013-09-01

Full Text Available BackgroundPathogens in the nasal cavity during nasal surgery could lead to a systemic infectious condition, such as bacteremia, nosocomial infection, or toxic shock syndrome. However, there is no research about the prevalence of nasal carriage in patients with nasal bone fracture.MethodsThis was a prospective, double-blind, randomized study about the rate of nasal carriage in 200 patients with nasal bone fracture in Korea. Nasal secretions were taken from both the middle nasal meatus and colonized. All analyses were carried out using SPSS software.ResultsPathogens were identified in 178 of the 200 cases. Coagulase-negative staphylococci (CNS were the most cultured bacteria in 127 (66.84% of the 190 total patients after excluding 10 cases of contaminated samples, and methicillin-resistant coagulase-negative staphylococci (MRCNS were found in 48 (25.26%. Staphylococcus aureus was the second most identified pathogen, found in 36 (18.95%, followed by 7 cases (3.68% of methicillin-resistant Staphylococcus aureus (MRSA. The prevalence rate of MRSA in the females was higher than that in the males (RR=4.70; 95% CI, 1.09-20.18, but other demographic factors had no effect on the prevalence rate of MRSA and MRCNS.ConclusionsThe prevalence rate of these pathogens in patients with nasal bone fracture in Korea was similar to other reports. However, few studies have addressed the prevalence rate of CNS and MRCNS in accordance with risk factors or the change in prevalence according to specific prophylaxis against infectious complications. Additional research is needed on the potential connections between clinical factors and microbiological data.

Sorveglianza delle infezioni ospedaliere: osservazioni presso il Presidio Ospedaliero di Penne (Pescara

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Dina Ridolfi

2006-12-01

Full Text Available Healthcare-associated infection is one of the major challenges to providing high quality healthcare. Faced with expectations to improve patient safety and contain costs, the health care system is under increasing pressure to comprehensively and objectively account for nosocomial infections. Laboratory records represent the main surveillance method for evaluation of healthcare-associated infections and antimicrobial drug resistance. Object:We review the occurrence, microbiology, risk factors for healthcare-associated infections, particularly antimicrobial drug resistance and diffusion of Staphylococcus aureus methicillin-resistant (MRSA among healthcare workers. Methods: Records from biological materials in the period January 1st 2000 and December 31st 2004 were considered. Isolated microrganisms, antibiotic assay (Vitek system, bioMérieux were analysed. 92 health care workers attending surgical theatre (surgical dept, ICU and anaesthesiology dept. were screened for MRSA. Results: 1754 bacteria were isolated. Escherichia coli was the more common bacteria (38%, followed by S. aureus, Enterococcus faecalis, Pseudomonas aeruginosa, Proteus mirabilis, Klebsiella pneumoniae, coagulase-negative staphylococci, and Enterobacter spp.The oxacillin resistance was 71% in coagulase-negative staphylococci, and 32% in S. aureus. Among the Enterobacteriaceae the more resistant has been the Enterobacter spp. Imipenem has demonstrated the highest antimicrobial activity (sensibility 82% in P. aeruginosa infections. Nasal plugs from healthcare workers demonstrated 40% colonized by S. aureus, and none of them carrier of MRSA. Conclusion: Laboratory chart review represent the mainstay for preventing of Nosocomial Infections. Prudent prescribing of antimicrobial drugs to hospital in patients may reduce incidences of antimicrobial drug resistance and healthcare-associated infections.The reservoirs for antibiotic-resistant organisms are colonized patients, and the

[Role of proton-motive force in the conjugative DNA transport in Staphylococci].

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Gavriliuk, V G; Vinnikov, A I

1997-01-01

Sensitivity of the conjugative process in staphylococci to the action of uncouplers of oxidative phosphorylation and inhibitors of electron transport systems have been proved, that testifies to the energy-dependent character of conjugative transport of DNA. Proceeding of the conjugation process depends upon the generation of delta microH+ on the membrane of both the donor and recipient cells. contribution of protonmotive forces to providing for the transfer of plasmids during conjugation to staphylococci has been defined.

The combination of ultrasound with antibiotics released from bone cement decreases the viability of planktonic and biofilm bacteria: an in vitro study with clinical strains.

Science.gov (United States)

Ensing, Geert T; Neut, Daniëlle; van Horn, Jim R; van der Mei, Henny C; Busscher, Henk J

2006-12-01

Antibiotic-loaded bone cements are used for the permanent fixation of joint prostheses. Antibiotic-loaded cements significantly decrease the incidence of infection. The objective of this study was to investigate whether the viability of bacteria derived from patients with a prosthesis-related infection could be further decreased when antibiotic release from bone cements was combined with application of pulsed ultrasound. Escherichia coli ATCC 10798, Staphylococcus aureus 7323, coagulase-negative staphylococci (CoNS 7368 and CoNS 7391) and Pseudomonas aeruginosa 5148 were grown planktonically in suspension and as a biofilm on three different bone cements: Palacos R without gentamicin as control, gentamicin-loaded Palacos R-G and gentamicin/clindamycin-loaded Copal. The viability of planktonic and biofilm bacteria was measured in the absence and presence of pulsed ultrasound for 40 h. Ultrasound itself did not affect bacterial viability. However, application of pulsed ultrasound in combination with antibiotic release by antibiotic-loaded bone cements yielded a reduction of both planktonic and biofilm bacterial viability compared with antibiotic release without application of ultrasound. This study shows that antibiotic release in combination with ultrasound increases the antimicrobial efficacy further than antibiotic release alone against a variety of clinical isolates. Application of ultrasound in combination with antibiotic release in clinical practice could therefore lead to better prevention or treatment of prosthesis-related infections.

The effects of daily chlorhexidine bathing on cutaneous bacterial isolates: a pilot study

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Soma VL

2012-04-01

Full Text Available Vijaya L Soma1, Xuan Qin2, Chuan Zhou1, Amanda Adler1, Jessica E Berry2, Danielle M Zerr11Department of Pediatrics, 2Department of Laboratory Medicine, University of Washington, Seattle, WA, USAAbstract: Chlorhexidine gluconate (CHG is a topical antiseptic used in a myriad of clinical settings. Recently, CHG baths have been shown to decrease multidrug-resistant organism acquisition and infections and catheter-associated bloodstream infections. The present study examined the effects of daily bathing with CHG on the recovery and antimicrobial susceptibility of cultivable cutaneous bacteria. The objectives of this study were to (1 explore the effects of clinical CHG bathing on cultivable cutaneous bacteria, (2 study the relationship between CHG minimum inhibitory concentration and antimicrobial susceptibility of coagulase-negative staphylococci, and (3 demonstrate the feasibility of the approach so a more definitive study may be performed. Significant decreases in bacterial colony counts and phenotypic diversity occurred with greater CHG exposure. The findings also suggest an inverse relationship between CHG minimum inhibitory concentration and antimicrobial susceptibility. Larger prospective studies are necessary to fully investigate the clinical impact of CHG usage.Keywords: antiseptic, resistance, Staphylococcus, coagulase-negative

Survey of Staphylococcus isolates among hospital personnel, environment and their antibiogram with special emphasis on methicillin resistance

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Shobha K

2005-01-01

Full Text Available The objective of this study was to find the prevalence of Staphylococcus spp. carriage among hospital personnel and hospital environment and their antibiogram with special emphasis on methicillin resistance. A total of 205 samples from hospital personnel and environment were collected from casualty, oncology and multidisciplinary cardiac unit ward of Kasturba Medical College Hospital, Manipal. Samples were collected using sterile cotton wool swabs and inoculated into brain heart infusion broth. Subcultures were done onto blood agar and MacConkey′s agar. Isolates were identified by standard methods up to species level. Antimicrobial susceptibility test was performed according to standardized disc diffusion Kirby-Bauer method. Each of the isolates was screened for methicillin resistance using oxacillin disc on Mueller Hinton agar plate followed by MIC for methicillin and cefoxitin susceptibility test by disc diffusion method. Sixty five out of 205 strains (31.7% were Staphylococcus spp. and all of them were coagulase negative. Most of the strains belonged to S.epidermidis 49.23%(32/65 followed by S. saprophyticus 26.15%(17/65. Maximum isolates of S.epidermidis were from anterior nares 28.12%(9/32 strains of S.epidermidis . Highest number of methicillin resistant coagulase negative strains (3/9, 33.33% were isolated from stethoscope of multidisciplinary cardiac unit ward followed by carriers in the anterior nares (2/9, 22.22%. Methicillin resistant coagulase negative staphylococci are prevalent in anterior nares of hospital personnel and in the hospital environment thereby providing a definite source for hospital acquired infection. All isolates were sensitive to vancomycin, ciprofloxacin and amikacin.

Are healthcare workers' mobile phones a potential source of nosocomial infections? Review of the literature.

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Ulger, Fatma; Dilek, Ahmet; Esen, Saban; Sunbul, Mustafa; Leblebicioglu, Hakan

2015-10-29

Mobile communication devices help accelerate in-hospital flow of medical information, information sharing and querying, and contribute to communications in the event of emergencies through their application and access to wireless media technology. Healthcare-associated infections remain a leading and high-cost problem of global health systems despite improvements in modern therapies. The objective of this article was to review different studies on the relationship between mobile phones (MPs) and bacterial cross-contamination and report common findings. Thirty-nine studies published between 2005 and 2013 were reviewed. Of these, 19 (48.7%) identified coagulase-negative staphylococci (CoNS), and 26 (66.7%) identified Staphylococcus aureus; frequency of growth varied. The use of MPs by healthcare workers increases the risk of repetitive cyclic contamination between the hands and face (e.g., nose, ears, and lips), and differences in personal hygiene and behaviors can further contribute to the risks. MPs are rarely cleaned after handling. They may transmit microorganisms, including multiple resistant strains, after contact with patients, and can be a source of bacterial cross-contamination. To prevent bacterial contamination of MPs, hand-washing guidelines must be followed and technical standards for prevention strategies should be developed.

Resistance to antimicrobials and biofilm formation in Staphylococcus spp. isolated from bovine mastitis in the Northeast of Brazil.

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da Costa Krewer, Carina; Santos Amanso, Evandro; Veneroni Gouveia, Gisele; de Lima Souza, Renata; da Costa, Mateus Matiuzzi; Aparecido Mota, Rinaldo

2015-03-01

Mastitis is the principal disease affecting dairy herds worldwide. The aim of the present study was to characterize phenotypic and genotypic features associated with resistance to antimicrobials in Staphylococcus spp. isolated from 2064 milk samples of 525 lactating cows in the Northeast of Brazil. Of the 218 isolates analyzed, 57.8% were characterized as Staphylococcus aureus, 28% as coagulase-positive staphylococci other than S. aureus (oCPS), and 14.2% as coagulase-negative staphylococci (CNS). The test for susceptibility to antimicrobials showed amoxicillin (32.6%) to be the less effective drug in vitro, and the multi-drug resistance (MDR) rate for beta-lactams varied from 0 to 0.75. The genotypic characterization showed that 93.1% of the samples were tested positive for the blaZ gene, while none amplified mecA. The antibiotic efflux mechanism was observed in 0.9% of isolates. The biofilm formation was found in 3.7 and 96.3% of samples, respectively, on Congo red agar and on the microplate adhesion test, while the icaD gene was present in 92.2% of Staphylococcus spp. The high frequency of blaZ gene observed in this study was associated with the resistance of most Staphylococcus spp. to one or more of the beta-lactams tested, which are routinely used in Brazilian herds for mastitis treatment. The biofilm formation was also detected in the isolates analyzed being an important characteristic for pathogenicity and antimicrobial resistance of bacteria.

Virulence factors genes of Staphylococcus spp. isolated from caprine subclinical mastitis.

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Salaberry, Sandra Renata Sampaio; Saidenberg, André Becker Simões; Zuniga, Eveline; Melville, Priscilla Anne; Santos, Franklin Gerônimo Bispo; Guimarães, Ednaldo Carvalho; Gregori, Fábio; Benites, Nilson Roberti

2015-08-01

The aim of this study was to investigate genes involved in adhesion expression, biofilm formation, and enterotoxin production in isolates of Staphylococcus spp. from goats with subclinical mastitis and associate these results with the staphylococcal species. One hundred and twenty-four isolates were identified and polymerase chain reaction (PCR) was performed to detect the following genes: cna, ebpS, eno, fib, fnbA, fnbB, bap, sea, seb, sec, sed and see. The most commonly Staphylococcus species included S. epidermidis, S. lugdunensis, S. chromogenes, S. capitis ss capitis and S. intermedius. With the exception of fnbB, the genes were detected in different frequencies of occurrence in 86.3% of the Staphylococcus spp. isolates. Eno (73.2%) and bap (94.8%) were more frequently detected in coagulase-negative staphylococci (CNS); ebpS (76%), fib (90.9%) and fnbA (87%) were the most frequent genes in coagulase-positive staphylococci (CPS). Regarding enterotoxins, genes sed (28.2%) and see (24.2%) had a higher frequency of occurrence; sec gene was more frequently detected in CPS (58.8%). There was no association between the presence of the genes and the Staphylococcus species. Different virulence factors genes can be detected in caprine subclinical mastitis caused by CNS and CPS. The knowledge of the occurrence of these virulence factors is important for the development of effective control and prevention measures of subclinical mastitis caused by CNS and CPS in goats. Copyright © 2015 Elsevier Ltd. All rights reserved.

A molecular epidemiological study of methicillin-resistant Staphylococci environmental contamination in railway stations and coach stations in Guangzhou of China.

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Lin, J L; Peng, Y; Ou, Q T; Lin, D X; Li, Y; Ye, X H; Zhou, J L; Yao, Z J

2017-02-01

Methicillin-resistant Staphylococcus aureus (MRSA) has caused a series of public health problems since it was first found in 1961. However, there are few research studies on the MRSA environmental contamination in railway stations and coach stations. Therefore, the aim of this study was to determine MRSA environmental contamination in public transport stations. Between December 2013 and January 2014, 380 surface samples from three railway stations (180) and four coach stations (200) in Guangzhou were collected to isolate and determine the prevalence and characteristics of Staphylococci strains. 39·21% of all samples were Staphylococci isolates, 1·58% of Staphylococci isolates were MRSA isolates, and 6·05% were methicillin-susceptible S. aureus. The proportion of multidrug resistant among 149 Staphylococci isolates was 75·84%. None of MRSA isolates was identified with the Panton-Valentine Leukocidin (PVL) genes, and one of them was identified with the qac gene. Four MRSA isolates were Staphylococcal Cassette Chromosome mec IVa, and the other two were nontypeable. Staphylococcus aureus isolates were classified into several sequence types (STs), and STs showed possible cross-transmissions of isolates from various sources. Methicillin-resistant Staphylococci contamination prevalence was high, and the environment of stations may be the vectors transmitting the Staphylococci to passengers. This is the first study to comprehensively report the prevalence, antibiotic resistance, and molecular characteristics of contamination of Staphylococci isolates in railway stations and coach stations of China. It will have great public health implications on infection control in community settings because of the serious hazard of Staphylococci, especially methicillin-resistant Staphylococci. Our findings have provided evidence for relevant departments to reduce the contamination of Staphylococci in environment of public transport stations. © 2016 The Society for Applied

Effects of fibrin, thrombin, and blood on breast capsule formation in a preclinical model.

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Marques, Marisa; Brown, Spencer A; Cordeiro, Natália D S; Rodrigues-Pereira, Pedro; Cobrado, M Luís; Morales-Helguera, Aliuska; Lima, Nuno; Luís, André; Mendanha, Mário; Gonçalves-Rodrigues, Acácio; Amarante, José

2011-03-01

The root cause of capsular contracture (CC) associated with breast implants is unknown. Recent evidence points to the possible role of fibrin and bacteria in CC formation. The authors sought to determine whether fibrin, thrombin, and blood modulated the histological and microbiological outcomes of breast implant capsule formation in a rabbit model. The authors carried out a case-control study to assess the influence of fibrin, thrombin, and blood on capsule wound healing in a rabbit model. Eighteen New Zealand white rabbits received four tissue expanders. One expander acted as a control, whereas the other expander pockets received one of the following: fibrin glue, rabbit blood, or thrombin sealant. Intracapsular pressure/volume curves were compared among the groups, and histological and microbiological evaluations were performed (capsules, tissue expanders, rabbit skin, and air). The rabbits were euthanized at two or four weeks. At four weeks, the fibrin and thrombin expanders demonstrated significantly decreased intracapsular pressure compared to the control group. In the control and fibrin groups, mixed inflammation correlated with decreased intracapsular pressure, whereas mononuclear inflammation correlated with increased intracapsular pressure. The predominant isolate in the capsules, tissue expanders, and rabbit skin was coagulase-negative staphylococci. For fibrin and thrombin, both cultures that showed an organism other than staphylococci and cultures that were negative were associated with decreased intracapsular pressure, whereas cultures positive for staphylococci were associated with increased intracapsular pressure. Fibrin application during breast implantation may reduce rates of CC, but the presence of staphylococci is associated with increased capsule pressure even in the presence of fibrin, so care should be taken to avoid bacterial contamination.

Antimicrobial susceptibility pattern and plasmid-mediated ...

African Journals Online (AJOL)

negative Staphylococci (CoNS) were isolated from clinical samples and isolates subjected to antibiotic susceptibility testing, plasmid curing and plasmid DNA isolation. Result: The highest percentages isolates were recovered from urine samples and ...

Plasmid-Mediated Antimicrobial Resistance in Staphylococci and Other Firmicutes.

Science.gov (United States)

Schwarz, Stefan; Shen, Jianzhong; Wendlandt, Sarah; Fessler, Andrea T; Wang, Yang; Kadlec, Kristina; Wu, Cong-Ming

2014-12-01

In staphylococci and other Firmicutes, resistance to numerous classes of antimicrobial agents, which are commonly used in human and veterinary medicine, is mediated by genes that are associated with mobile genetic elements. The gene products of some of these antimicrobial resistance genes confer resistance to only specific members of a certain class of antimicrobial agents, whereas others confer resistance to the entire class or even to members of different classes of antimicrobial agents. The resistance mechanisms specified by the resistance genes fall into any of three major categories: active efflux, enzymatic inactivation, and modification/replacement/protection of the target sites of the antimicrobial agents. Among the mobile genetic elements that carry such resistance genes, plasmids play an important role as carriers of primarily plasmid-borne resistance genes, but also as vectors for nonconjugative and conjugative transposons that harbor resistance genes. Plasmids can be exchanged by horizontal gene transfer between members of the same species but also between bacteria belonging to different species and genera. Plasmids are highly flexible elements, and various mechanisms exist by which plasmids can recombine, form cointegrates, or become integrated in part or in toto into the chromosomal DNA or into other plasmids. As such, plasmids play a key role in the dissemination of antimicrobial resistance genes within the gene pool to which staphylococci and other Firmicutes have access. This chapter is intended to provide an overview of the current knowledge of plasmid-mediated antimicrobial resistance in staphylococci and other Firmicutes.

Kinetic study on coagulase formation and growth of 'Staphylococcus aureus': comparative and combined action of antibiotics and gamma radiation

International Nuclear Information System (INIS)

Kiortsis, M.

1980-01-01

Coagulase production is preserved in Staphylococcus aureus cultures although growth was strongly reduced after irradiation with 90,000 rads by a 60 Co source. Kinetic studies on the growth and coagulase formation by non-irradiated and irradiated bacteria are reported, using various antibiotics such as chloramphenicol, actinomycin D and mitomycin. Both chloramphenicol (1-50 μg/ml) and actinomycin D (0.05-0.8 μg/ml) added to S. aureus cultures reduce and finally inhibit growth rate and coagulase synthesis proportionally to their concentration in the medium; irradiated and non-irradiated cultures behave similarly to the inhibitory action of those antibiotics. Mitomycin between 0.2-9.6 μg/ml reduces growth, but enzyme production is slightly affected; high levels of coagulase are observed in non-growing cultures. Mitomycin and gamma radiation affecting DNA give similar results: inhibition of growth but not of enzyme formation. Kinetic studies show that coagulase is synthesized during the first five minutes either in irradiated or in non-irradiated cultures. Indication of a de novo synthesis, instead of a mere release of ready-formed enzyme, is given by using chloramphenicol or actinomycin which strongly inhibit coagulase production in irradiated S. aureus. Cultures treated by those antibiotics have their coagulase levels reduced to the same degree, were they irradiated or not; it is assumed that both types of cultures behave similarly, as far as enzyme production is concerned. A massive irradiation dose alone -or mitomycin in high concentrations alone- may suspend bacterial growth although enzyme synthesis continues. A similar result is obtained by combining lower irradiation doses with an appropriate antibiotic. The combined and/or synergistic actions of gamma radiation and antibiotics could successfully differentiate between the two cellular functions: growth and enzyme synthesis [fr

Incidence of enterotoxigenic staphylococci and their toxins in foods.

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Soriano, J M; Font, G; Rico, H; Moltó, J C; Mañes, J

2002-05-01

Of 504 food samples collected from cafeterias, 19 (3.8%) yielded strains of enterotoxigenic staphylococci, and 10 (52.6%), 4 (21.1%), 3 (15.8%), and 2 (10.5%) of these strains produced enterotoxins C (SEC), D (SED), B (SEB), and A (SEA), respectively. Moreover, SEA, SEB, and SEC were isolated from three hamburger samples. Of 181 food samples collected from four restaurants before the implementation of the hazard analysis and critical control point (HACCP) system, 7 (3.9%) were found to contain enterotoxigenic strains, and SED, SEC, and SEA were produced by 4 (57.1%), 2 (28.6%), and 1 (14.3%) of these strains, respectively. One meatball sample with SEC was detected in a restaurant. After the implementation of the HACCP system in four restaurants, neither enterotoxigenic staphylococci nor enterotoxins were detected in 196 studied samples.

Ultrastructural changes in biofilm forms of staphylococci cultivated in a mixed culture with lactobacilli

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G. Lavryk

2017-02-01

Full Text Available The capacity of opportunistic bacteria for biofilm formation plays an important role in the development of chronic inflammatory processes, which are difficult to treat. To improve antimicrobial therapy methods, the influence of lactobacilli on the ultrastructure of biofilm-forming clinical strains of staphylococci when co-cultured was investigated. 5 biofilm-forming clinical strains of S. aureus from the skin of acne vulgaris patients (n = 24 were isolated. Using transmission electron microscopy (TEM the morphological changes of S. aureus cells in the mixed culture with standard strains of Lactobacillus plantarum 8P-A3 and clinical strains of L. fermentum (n = 4 were studied. It was found that in 48 hours after the inoculation on the medium of samples of mixed cultures of L. plantarum 8P-A3 and S. aureus growth of staphylococci was not revealed. Only in some cases of mixed cultures of L. fermentum and biofilm-forming staphylococci was growth of S. aureus obtained. In electron diffraction patterns of control samples of 24-hour staphylococcal monocultures and 48-hour lactobacilli monocultures, natural development of the population at the cellular level was observed. Destructive changes under the influence of lactobacilli (probiotic and clinical strains were detected in all ultrathin sections of the cells of biofilm-forming and planktonic staphylococci. Significant destructive changes in the cell wall of the staphylococci were observed: thickening, obtaining of irregular form, detachment of the cytoplasmic membrane, the complete destruction of the peptidoglycan layer and the emergence of "shadow cells". On all electron diffraction patterns fibrillar-threadlike structures of DNA could not be observed, but in some cases mesosome-like formations were poorly contrasted. It was established that the surface S-layer of lactobacilli was expressed on a significantly larger scale in the mixed culture with staphylococci. In mixed culture of clinical strains

Antibiotic resistance profile of staphylococci from clinical sources ...

African Journals Online (AJOL)

JOHN

was recorded in 2 infants while another 2 had impetigo along with urinary tract infection. Urinary tract infection with skin sepsis was recorded in 6 subjects and tetanus occurred along with septicemia in 2 subjects. Distribution of Staphylococci. Altogether, a total of 178 staphylococcal isolates were cultured from 245 samples ...

Study of conjunctival flora in patients after peripheral blood stem cell transplantation and its correlation with tear secretion

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Shin-Yi Chen

2012-12-01

Full Text Available Background: Human tear film plays an important role in protecting the ocular surface against vari­ous pathogens. Dry eye, the major ocular complication of peripheral blood stem cell trans­plantation (PBSCT, may predispose bacterial colonization to the conjunctiva, and increase the risk of infectious keratitis. The aim of this study is to investigate the con­junctival bacterial flora in patients receiving PBSCT and to stratify the severity of dry eye for comparison. Methods: This cross-sectional study encompassed patients who received PBSCT from 2002 to 2008 in our hospital. At least 1 year after PBSCT, patients were re-evaluated for ocu­lar surface status, and bacterial culture of the conjunctival sac was performed. The eyes of patients were divided into three groups in accordance to the result of the Schirmer Ia test. In the control group, we enrolled dry-eye patients with underlying dis­ease other than hematopoietic stem cell transplantation of which the age range was simi­lar to the study group. Results: Thirty-six patients with 72 eyes were included in our study. The first group (n=36 was defined as having Schirmer Ia test result of 0-5 mm, and the culture of conjuncti­val sac were positive in 8 eyes (22%. The second group (n=20 was defined as having Schirmer Ia result between 6 and 9 mm, and 4 of which were positive for bacterial cul­ture (20%. In the third group (n=16 with Schirmer Ia result of ≧10mm, flora in pa­tients receiving PBSCT were coagulase-negative Staphylococci, Staphylococcus au­reus and Corynebacterium sp. The bacterial colonization rate in the post-PBSCT group was not higher than the control group (22.2% vs. 30.8%, and coagulase-nega­tive Staphylococci was the most common flora in the control group. Conclusion: Despite not having statistical significance, there seems to be a positive correlation be­tween the colonization rate and the severity of dry eye. However, bacterial profile iso­lated in post

Prevalence of mecA gene among staphylococci from clinical ...

African Journals Online (AJOL)

Background: The staphylococci have increasingly been associated with infections worldwide and anti-microbial resistance has made these versatile pathogens more recalcitrant in the hospital setting. Objectives: This study sought to investigate the occurrence and distribution of Staphylococcus species as well as determine ...

Persistence of mixed staphylococci assemblages following disinfection of hospital room surfaces.

Science.gov (United States)

Sigler, V; Hensley, S

2013-03-01

The distribution of staphylococcal assemblages on surfaces in hospital rooms was assessed before and after daily disinfection with quaternary ammonia products. DNA was extracted from enrichment cultures of bacteria, which were swabbed from each of nine surface types, and subjected to analysis by staphylococci-specific, denaturing gradient gel electrophoresis. A genetic marker for Staphylococcus epidermidis/kloosii was detected on all surface types before and after cleaning, whereas markers for Staphylococcus aureus and Staphylococcus lugdunensis were detected on five surface types. Overall, genetic makers for several staphylococci known to colonize and infect humans remained ubiquitous in each room following daily disinfection practices. Copyright © 2013 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

In vitro antibacterial activity of doripenem against clinical isolates from French teaching hospitals: proposition of zone diameter breakpoints.

Science.gov (United States)

Lascols, C; Legrand, P; Mérens, A; Leclercq, R; Armand-Lefevre, L; Drugeon, H B; Kitzis, M D; Muller-Serieys, C; Reverdy, M E; Roussel-Delvallez, M; Moubareck, C; Lemire, A; Miara, A; Gjoklaj, M; Soussy, C-J

2011-04-01

The aims of the study were to determine the in vitro activity of doripenem, a new carbapenem, against a large number of bacterial pathogens and to propose zone diameter breakpoints for clinical categorization in France according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) minimum inhibitory concentration (MIC) breakpoints. The MICs of doripenem were determined by the broth microdilution method against 1,547 clinical isolates from eight French hospitals. The disk diffusion test was performed (10-μg discs) according to the Comité de l'Antibiogramme de la Société Française de Microbiologie (CASFM) method. The MIC(50/90) (mg/L) values were as follows: methicillin-susceptible Staphylococcus aureus (MSSA) (0.03/0.25), methicillin-resistant Staphylococcus aureus (MRSA) (1/2), methicillin-susceptible coagulase-negative staphylococci (MSCoNS) (0.03/0.12), methicillin-resistant coagulase-negative staphylococci (MRCoNS) (2/8), Streptococcus pneumoniae (0.016/0.25), viridans group streptococci (0.016/2), β-hemolytic streptococci (≤0.008/≤0.008), Enterococcus faecalis (2/4), Enterococcus faecium (128/>128), Enterobacteriaceae (0.06/0.25), Pseudomonas aeruginosa (0.5/8), Acinetobacter baumannii (0.25/2), Haemophilus influenzae (0.12/0.25), and Moraxella catarrhalis (0.03/0.06). According to the regression curve, the zone diameter breakpoints were 24 and 19 mm for MICs of 1 and 4 mg/L, respectively. This study confirms the potent in vitro activity of doripenem against Pseudomonas aeruginosa, Acinetobacter, Enterobacteriaceae, MSSA, MSCoNS, and respiratory pathogens. According to the EUCAST MIC breakpoints (mg/L) ≤1/>4 for Enterobacteriaceae, Pseudomonas aeruginosa, and Acinetobacter, and ≤1/>1 for streptococci, pneumococci, and Haemophilus, the zone diameter breakpoints could be (mm) ≥24/<19 and ≥24/<24, respectively.

Mediation analysis to estimate direct and indirect milk losses due to clinical mastitis in dairy cattle.

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Detilleux, J; Kastelic, J P; Barkema, H W

2015-03-01

Milk losses associated with mastitis can be attributed to either effects of pathogens per se (i.e., direct losses) or effects of the immune response triggered by intramammary infection (indirect losses). The distinction is important in terms of mastitis prevention and treatment. Regardless, the number of pathogens is often unknown (particularly in field studies), making it difficult to estimate direct losses, whereas indirect losses can be approximated by measuring the association between increased somatic cell count (SCC) and milk production. An alternative is to perform a mediation analysis in which changes in milk yield are allocated into their direct and indirect components. We applied this method on data for clinical mastitis, milk and SCC test-day recordings, results of bacteriological cultures (Escherichia coli, Staphylococcus aureus, Streptococcus uberis, coagulase-negative staphylococci, Streptococcus dysgalactiae, and streptococci other than Strep. dysgalactiae and Strep. uberis), and cow characteristics. Following a diagnosis of clinical mastitis, the cow was treated and changes (increase or decrease) in milk production before and after a diagnosis were interpreted counterfactually. On a daily basis, indirect changes, mediated by SCC increase, were significantly different from zero for all bacterial species, with a milk yield decrease (ranging among species from 4 to 33g and mediated by an increase of 1000 SCC/mL/day) before and a daily milk increase (ranging among species from 2 to 12g and mediated by a decrease of 1000 SCC/mL/day) after detection. Direct changes, not mediated by SCC, were only different from zero for coagulase-negative staphylococci before diagnosis (72g per day). We concluded that mixed structural equation models were useful to estimate direct and indirect effects of the presence of clinical mastitis on milk yield. Copyright © 2015 Elsevier B.V. All rights reserved.

The Evolving Nature of Infective Endocarditis in Spain: A Population-Based Study (2003 to 2014).

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Olmos, Carmen; Vilacosta, Isidre; Fernández-Pérez, Cristina; Bernal, José L; Ferrera, Carlos; García-Arribas, Daniel; Pérez-García, Carlos N; San Román, J Alberto; Maroto, Luis; Macaya, Carlos; Elola, Francisco J

2017-12-05

Little information exists regarding population-based epidemiological changes in infective endocarditis (IE) in Europe. This study sought to analyze temporal trends in IE in Spain from 2003 to 2014. This retrospective, population-based, temporal trend study analyzed the incidence, epidemiological and clinical characteristics, and outcome of all patients discharged from hospitals included in the Spanish National Health System with a diagnosis of IE, from January 2003 to December 2014. Overall, 16,867 episodes of IE were identified during the study period, 66.3% in men. The rate of IE significantly increased, from 2.72 in 2003 to 3.49 per 100,000 person-years in 2014, and this rise was higher among older adults. The most frequent microorganisms were staphylococci (28.7%), followed by streptococci (20.4%) and enterococci (13.1%). Twenty-three percent of patients underwent cardiac surgery. The in-hospital mortality rate was 20.4%. Throughout the study period, the proportion of patients with previously known heart valve disease and diabetes mellitus significantly increased, whereas the prevalence of intravenous drug use decreased. Regarding microorganisms, Staphylococcus aureus and streptococci slightly declined, whereas coagulase-negative staphylococci and enterococci consistently increased over the years. In-hospital complications and cardiac surgery rates significantly increased across the years. The risk-adjusted in-hospital mortality rate diminished (0.2% per year) during the study period. The incidence of IE episodes significantly increased over the decade of the study period, particularly among older adults. Relevant changes in clinical and microbiological profile included older patients with more comorbidity and a rise in enterococci and coagulase-negative staphylococcal infections. Adjusted mortality rates slightly declined over the study period. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights

Matrix-assisted laser desorption ionization time of flight mass spectrometry and diagnostic testing for prosthetic joint infection in the clinical microbiology laboratory.

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Peel, Trisha N; Cole, Nicolynn C; Dylla, Brenda L; Patel, Robin

2015-03-01

Identification of pathogen(s) associated with prosthetic joint infection (PJI) is critical for patient management. Historically, many laboratories have not routinely identified organisms such as coagulase-negative staphylococci to the species level. The advent of matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) has enhanced clinical laboratory capacity for accurate species-level identification. The aim of this study was to describe the species-level identification of microorganisms isolated from periprosthetic tissue and fluid specimens using MALDI-TOF MS alongside other rapid identification tests in a clinical microbiology laboratory. Results of rapid identification of bacteria isolated from periprosthetic joint fluid and/or tissue specimens were correlated with clinical findings at Mayo Clinic, Rochester, Minnesota, between May 2012 and May 2013. There were 178 PJI and 82 aseptic failure (AF) cases analyzed, yielding 770 organisms (median, 3/subject; range, 1-19/subject). MALDI-TOF MS was employed for the identification of 455 organisms (59%) in 197 subjects (123 PJIs and 74 AFs), with 89% identified to the species level using this technique. Gram-positive bacteria accounted for 68% and 93% of isolates in PJI and AF, respectively. However, the profile of species associated with infection compared to specimen contamination differed. Staphylococcus aureus and Staphylococcus caprae were always associated with infection, Staphylococcus epidermidis and Staphylococcus lugdunensis were equally likely to be a pathogen or a contaminant, whereas the other coagulase-negative staphylococci were more frequently contaminants. Most streptococcal and Corynebacterium isolates were pathogens. The likelihood that an organism was a pathogen or contaminant differed with the prosthetic joint location, particularly in the case of Propionibacterium acnes. MALDI-TOF MS is a valuable tool for the identification of bacteria isolated from patients

Effect of perioperative mupirocin and antiseptic body wash on infection rate and causative pathogens in patients undergoing cardiac surgery.

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Kohler, Philipp; Sommerstein, Rami; Schönrath, Felix; Ajdler-Schäffler, Evelyne; Anagnostopoulos, Alexia; Tschirky, Sandra; Falk, Volkmar; Kuster, Stefan P; Sax, Hugo

2015-07-01

Preoperative nasal mupirocin has been shown to reduce surgical site infections (SSIs) in patients undergoing cardiac surgery. We analyzed the effect of mupirocin plus antiseptic body wash on SSI rate and etiology. Prospective SSI surveillance was done for patients undergoing cardiac surgery before and after implementation of mupirocin nasal ointment and chlorhexidine/octenidine body wash. Overall SSI rate was 8.6% (81 out of 945) for the control and 6.9% (58 out of 842) for the intervention cohort (P = .19). In multivariable analysis, the study protocol was associated with an odds ratio of 0.61 (95% confidence interval, 0.41-0.91; P = .015) with regard to any SSI. This effect was exclusively due to a reduction in superficial SSIs and was observed both in patients with preoperative and postoperative treatment initiation. Coagulase-negative staphylococci (CoNS), the most commonly isolated pathogen, were found in 37% and 48% (P = .19) of patients in the control and the intervention cohort, respectively. CoNS were methicillin resistant in 69% of cases. Mupirocin and antiseptic body wash reduced the rate of superficial but not deep or organ/space SSIs. Postoperative patient treatment may be critical in reducing the risk for superficial SSI, presumably due to a reduction of bacterial skin load. A high proportion of SSI was due to methicillin-resistant CoNS and thus not covered by routine perioperative antimicrobial prophylaxis. Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

Bacteraemia Due to ESKAPE Pathogens: An Emerging Problem in Cancer Patients

International Nuclear Information System (INIS)

El-Mahallawy, H.A.; Hassan, S.S.; El-Wakil, M.; Moneer, M.M.

2016-01-01

Background and aim: In recent years, a few of the antibiotic-resistant bacteria, known as ESKAPE pathogens, have been found responsible for serious infections. We investigated the risk factors, and impact of ESKAPE pathogens on course of blood stream infections (BSIs) in cancer patients in comparison to coagulase negative Staphylococci (CoNS). Patients and methods: The data of patients with ESKAPE positive blood cultures at National Cancer Institute, Cairo University were analyzed. Identification and antimicrobial susceptibility of isolates were done using Microscan Walk Away 96. Results: In a 6 month period, ESKAPE pathogens were isolated from non-duplicate blood cultures in 81 episodes of 72 cases of pediatric cancer patients, while CoNS were isolated from 135 blood cultures of 116 patients. The ESKAPE pathogens isolated were Enterobacter spp., methicillin- resistant Staphylococcus aureus (MRSA), Klebsiella pneumoniae , Acinetobacter baumannii , Pseudomonas aeruginosa , and Enterococci in 12%, 23%, 37%, 10%, 9%, and 9% of episodes, respectively. Health-care acquired infections constituted 75% of ESKAPE infections. Duration of episodes and overall mortality were significantly higher in ESKAPE BSIs when compared to CoNS (14.5 ± 7.6 versus 09.9 ± 6.9), and (26% versus 4%); respectively, p value <0.001. Conclusions: ESKAPE pathogens were significantly associated with higher rates of morbidity and mortality indicating the need for improving the means of prevention of these types of infections within health care premises. Microbiology laboratories have a role in defining more dangerous infections and rapid diagnostics are required in the era of resistance.

Presence of Staphylococcus spp. and Candida spp. in the human oral cavity

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Martins Clélia Aparecida de Paiva

2002-01-01

Full Text Available The presence of yeasts and staphylococci in the oral cavity is important because they can act as supplementary microbiota and in certain situations can cause oral or systemic diseases. The aim of this work was to study the prevalence of Candida spp. and Staphylococcus spp. in the human oral cavity. Oral rinses were collected from sixty-eight individuals according to the technique described by Samaranayake and MacFarlane and then cultured on Sabouraud medium supplemented with chloramphenicol and Baird-Parker agar. After the incubation period, the microorganisms were isolated and identified through biochemical tests. The data obtained were statistically analysed by ANOVA. Candida spp. were isolated from 61.76% of the examined individuals and C. albicans was the more frequently isolated specie. Staphylococcus spp. were isolated from 95.60% of the individuals and 41 strains were coagulase negative (63%. Among the coagulase positive strains, nine were S. aureus, 11 S. hyicus and 4 S. schleiferi subspecie coagulans. No correlation was observed between the counts (cfu of the isolated Candida spp. and Staphylococcus spp.

The diversities of staphylococcal species, virulence and antibiotic resistance genes in the subclinical mastitis milk from a single Chinese cow herd.

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Xu, Jia; Tan, Xiao; Zhang, Xinyu; Xia, Xiaoli; Sun, Huaichang

2015-11-01

Staphylococci are the leading pathogens of bovine mastitis which is difficult to control. However, the published data on the prevalence of staphylococcal species, virulence and antibiotic resistance genes in bovine mastitis from China are limited. In this study, 104 out of 209 subclinical mastitis milk samples from a single Chinese dairy herd were cultured-positive for staphylococci (49.8%), which were further identified as coagulase-positive staphylococci (CPS) or coagulase-negative staphylococci (CNS). According to the partial tuf and/or 16S rRNA gene sequence, the 28 CPS isolates were confirmed to be Staphylococcus aureus (26.9%), and 76 CNS isolates were assigned to 13 different species (73.1%) with Staphylococcus arlettae, Staphylococcus sciuri, Staphylococcus xylosus and Staphylococcus chromogenes as the dominant species. In the 28 S. aureus isolates, the most prevalent general virulence genes were coa, Ig and eno (100%), followed by hla (96.4%), hlb (92.9%), fib (92.9%), clfA (89.3%), clfB (85.7%) and nuc (85.7%). Both exotoxin and biofilm-associated genes were significantly less prevalent than the previously reported. Although 19 different virulence gene patterns were found, only one was dominant (32.1%). The prevalence of blaZ (82.1%) or mecA gene (35.7%) was much higher than the previously reported. In the 76 CNS isolates, the virulence genes were significantly less prevalent than that in the S. aureus isolates. Among the 4 main CNS species, S. chromogenes (n = 12) was the only species with high percentage (75%) of blaZ gene, while S. sciuri (n = 12) was the only species with the high percentage (66.7%) of mecA gene. The most of antibiotic resistance genes were present as multi-resistance genes, and the antibiotic resistances were attributed by different resistance genes between resistant S. aureus and CNS isolates. These data suggest that the prevalence of staphylococcal species, virulence and antibiotic resistance in the mastitis milk from the Chinese

Native Chromium Resistant Staphylococci Species from a Fly Ash ...

African Journals Online (AJOL)

Sixty-six chromium-resistant Staphylococci species belonging to S. epidermidis, S. aureus, S. saprophyticus and S. arlettae were previously isolated from a chromium-polluted Fly ash (FA) dumping site in South Africa. However the genetic mechanisms responsible for chromium resistance were not known. Polymerase chain ...

Use of tuf as a target for sequence-based identification of Gram-positive cocci of the genus Enterococcus, Streptococcus, coagulase-negative Staphylococcus, and Lactococcus

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Li Xuerui

2012-11-01

Full Text Available Abstract Background Accurate identification of isolates belonging to genus Enterococcus, Streptococcus, coagulase-negative Staphylococcus, and Lactococcus at the species level is necessary to provide a better understanding of their pathogenic potential, to aid in making clinical decisions, and to conduct epidemiologic investigations,especially when large blind samples must be analyzed. It is useful to simultaneously identify species in different genera using a single primer pair. Methods We developed a primer pair based on the tuf gene (encoding elongation factor sequence to identify 56 Gram-positive cocci isolates. Results The target sequences were amplified from all 56 samples. The sequencing results and the phylogenetic tree derived from the partial tuf gene sequences identified the isolates as three enterococcal species, two lactococcal species, two staphylococcal species, and six streptococcal species, as well as eight isolates that were novel species of the genus Streptococcus. Partial gene sequence analysis of the sodA, dnaK, and 16S RNA genes confirmed the results obtained by tuf gene sequencing. Conclusion Based on the uniform amplification of the tuf gene from all samples and the ability to identify all isolates at both the genus and species levels, we conclude that the primer pair developed in this research provides a powerful tool for identifying these organisms in clinical laboratories where large blind samples are used.

Environmental gram-positive mastitis treatment: in vitro sensitivity and bacteriologic cure.

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Cattell, M B; Dinsmore, R P; Belschner, A P; Carmen, J; Goodell, G

2001-09-01

A clinical trial was conducted in a large dairy herd to determine the efficacy of intramammary pirlimycin hydrochloride administration during lactation for bacteriologic clearance of gram-positive environmental clinical and subclinical mastitis infections. Quarters infected with environmental streptococci that received pirlimycin therapy (13/28) were 1.8 times more likely to resolve infection than untreated quarters (5/14). The small numbers of quarters infected with coagulase-negative staphylococci resulted in inadequate power to assess treatment differences in cure rate. Although the association was not statistically significant, quarters from cows with sensitive environmental streptococci isolates from composite samples (8/13) resolved infection with treatment at approximately twice the rate of treated quarters with resistant isolates (3/10).

Emerging mastitis pathogens

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Janus. A

2009-02-01

Full Text Available Mastitis means inflammation of the parenchyma of the mammary gland. Many infective agents have been implicated as causes of mastitis. Worldwide, farmers have achieved tremendous success in reducing the incidence of contagious mastitis by adopting the traditional methods of mastitis control. The greatest impact of these control measures has been on infections caused by the contagious bacteria such as Staphylococcus aureus and Streptococcus agalactia. But this success has not been demonstrated for clinical mastitis caused by other agents. Organisms such as coagulase negative Staphylococci, environmental Streptococci, Mycoplasma spp and Serratia spp have increasingly been isolated from dairy herds that had low somatic cell counts. [Vet. World 2009; 2(1.000: 38-39

The Current State of Screening and Decolonization for the Prevention of Staphylococcus aureus Surgical Site Infection After Total Hip and Knee Arthroplasty.

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Weiser, Mitchell C; Moucha, Calin S

2015-09-02

The most common pathogens in surgical site infections after total hip and knee arthroplasty are methicillin-sensitive Staphylococcus aureus (MSSA), methicillin-resistant S. aureus (MRSA), and coagulase-negative staphylococci. Patients colonized with MSSA or MRSA have an increased risk for a staphylococcal infection at the site of a total hip or knee arthroplasty. Most colonized individuals who develop a staphylococcal infection at the site of a total hip or total knee arthroplasty have molecularly identical S. aureus isolates in their nares and wounds. Screening and nasal decolonization of S. aureus can potentially reduce the rates of staphylococcal surgical site infection after total hip and total knee arthroplasty. Copyright © 2015 by The Journal of Bone and Joint Surgery, Incorporated.

DETECTION OF BIOFILM PRODUCTION IN BLOOD CULTURE ISOLATES OF STAPHYLOCOCCI

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Gupta Puja, Gupta Pratima, Mittal Garima, Agarwal RK, Goyal Rohit

2015-01-01

Full Text Available Background: Biofilm producing bacteria which are inherently resistant to antibiotics and disinfectants are widely associated with implant associated infections. Staphylococcus is the most commonly associated pathogens with bloodstream infection. Aims: The current study was conducted to detect biofilm production in Staphylococci isolated from blood culture specimens. Materials and Methods: 70 clinically significant staphylococcal isolates from blood culture were screened for biofilm production by Tissue culture plate (TCP method, Tube method (TM and Congo red agar (CRA method and their antibiotic susceptibility profile was studied. Results: 59 out of 70 staphylococcal isolates were positive by TCP, out of these 21.4% staphylococci were high biofilm producers, 62.8% staphylococci were moderate biofilm producers and 15.8% were non-biofilm producers. Maximum resistance was observed in biofilm producers to cotrimoxazole (74.5% and erythromycin (62.7% and none were resistant to vancomycin and linezolid. Out of total 59 biofilm producers, 20.3 % (12 were methicillin resistant and all these were S. aureus isolates. 19% (1 out of total 11 biofilm non-producers were methicillin resistant. Conclusion: Biofilm production was seen to be a major virulence factor in most of the staphylococcal isolates obtained from patients with signs and symptoms of septicaemia. S. aureus was found to be the major pathogen and timely detection of biofilm producing phenotype should be carried out using a simple and reproducible method, TCP which is both qualitative and quantitative.

Infecciones intrahospitalarias en pacientes pediátricos con enfermedades hematológicas, 2006-2009 Nosocomial infections in pediatric patients with hematological diseases, 2006-2009

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Librada Martell-Martorell

2012-09-01

Full Text Available Se realizó un estudio descriptivo transversal en el Servicio de Pediatría del Instituto de Hematología e Inmunología, en el período comprendido entre diciembre de 2006 y marzo de 2009. Se incluyeron 36 pacientes que presentaron 60 infecciones con documentación microbiológica, lo que representó el 29 % del total. La mayoría de las infecciones se presentaron en pacientes con hemopatías malignas, de los cuales una gran parte tuvo neutropenia severa. En los episodios infecciosos las bacterias gramnegativas fueron las más frecuentes, seguidas de las grampositivas y los hongos, estos últimos siempre asociados con infecciones bacterianas. El estafilococo coagulasa negativo fue el microorganismo de mayor incidencia. Los pacientes que tuvieron colocado el catéter venoso central en región femoral tuvieron mayor riesgo de presentar bacteriemia por bacilos gramnegativos.A cross-sectional study was performed at the Pediatric Department of the Institute of Hematology and Immunology from December 2006 to March 2009. There were 36 patients who had 60 infections with microbiological documentation, which represented 29 % of the total. Most infections occurred in patients with hematological malignancies, of which a large portion had severe neutropenia. In infectious episodes Gram-negative bacteria was the most frequent, followed by Gram positive and fungi, this latter was always associated with bacterial infections. Coagulase negative staphylococcus was the organism with the highest incidence. Patients who had central venous catheter placed in the femoral region had a higher risk of negative bacilli bacteremia.

Proposal for agar disk diffusion interpretive criteria for susceptibility testing of bovine mastitis pathogens using cefoperazone 30μg disks.

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Feßler, Andrea T; Kaspar, Heike; Lindeman, Cynthia J; Peters, Thomas; Watts, Jeffrey L; Schwarz, Stefan

2017-02-01

Cefoperazone is a third generation cephalosporin which is commonly used for bovine mastitis therapy. Bacterial pathogens involved in bovine mastitis are frequently tested for their susceptibility to cefoperazone. So far, the cefoperazone susceptibility testing using 30μg disks has been hampered by the lack of quality control (QC) ranges as well as the lack of interpretive criteria. In 2014, QC ranges for 30 μg cefoperazone disks have been established for Staphylococcus aureus ATCC ® 25923 and Escherichia coli ATCC ® 25922. As a next step, interpretive criteria for the susceptibility testing of bovine mastitis pathogens should be developed. For this, 637 bovine mastitis pathogens (including 112 S. aureus, 121 coagulase-negative staphylococci (CoNS), 103 E. coli, 101 Streptococcus agalactiae, 100 Streptococcus dysgalactiae and 100 Streptococcus uberis) were investigated by agar disk diffusion according to the document Vet01-A4 of the Clinical and Laboratory Standards Institute (CLSI) using 30μg cefoperazone disks and the results were compared to the corresponding MIC values as determined by broth microdilution also according to the aforementioned CLSI document. Based on the results obtained and taking into account the achievable milk concentration of cefoperazone after regular dosing, the following interpretive criteria were proposed as a guidance for mastitis diagnostic laboratories: for staphylococci and E. coli ≥23mm (susceptible), 18-22mm (intermediate) and ≤17mm (resistant) and for streptococci ≥18mm (susceptible), and ≤17mm (non-susceptible). These proposed interpretive criteria shall contribute to a harmonization of cefoperazone susceptibility testing of bovine mastitis pathogens. Copyright © 2016 Elsevier B.V. All rights reserved.

Impact of a rapid molecular test for positive blood cultures from neonatal intensive care patients on clinical management: a retrospective audit.

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Koh, L L; O'Rourke, S; Brennan, M; Clooney, L; Cafferkey, M; McCallion, N; Drew, R J

2018-05-01

Both Staphylococcus aureus and coagulase negative Staphylococci are common causes of late-onset neonatal sepsis in the neonatal intensive care unit (NICU), usually relating to intravascular access device infections. This project aimed to review the impact on antimicrobial treatment and clinical outcome in the NICU setting, of the introduction of the Xpert MRSA/SA BC test (Cepheid, USA) for the identification of staphylococci in blood cultures. A retrospective audit was carried out of the pre- and post-intervention periods; the intervention was the introduction of the Xpert MRSA/SA BC test. In total, 88 neonates had positive blood cultures with Staphylococcus spp., comprising 42 neonates in the pre-intervention and 46 in the post-intervention groups. The pre-intervention group had a higher birth weight (1.541 kg vs. 1.219 kg, p = 0.05) and higher platelet count (288 vs. 224 × 10 9 /L, p = 0.05). There was a trend towards a shorter duration of antimicrobial therapy in term infants and in the length of admission; however, this was not statistically significant (p = 0.2). All of the nine infants post-intervention with significant bacteraemia (S. aureus =3, CoNS =6) were changed to the optimal antimicrobial at the time the result was available. This study shows that the introduction of the Xpert MRSA/SA BC test can lead to a reduction in the length of admission and duration of antimicrobials in term infants; however, the difference was not statistically significant. All nine infants with clinically significant bacteraemia were treated with the appropriate antimicrobial when the Xpert MRSA/SA BC test result was available.

Staphylococcus lugdunensis Endocarditis Complicated by Embolism in an 18-Year-Old Woman with Mitral Valve Prolapse

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Pecoraro, Rosaria; Tuttolomondo, Antonino; Parrinello, Gaspare; Pinto, Antonio; Licata, Giuseppe

2013-01-01

Staphylococcus lugdunensis is a coagulase-negative staphylococcus (CNS). It is a major cause of prosthetic valve endocarditis; mitral valve prolapse (MVP) has emerged as a prominent predisposing structural cardiac abnormality. We describe a case of Staphylococcus lugdunensis endocarditis in an 18-year-old woman with preexisting mitral valve prolapse complaining of fever, a one-month history of continuous-remittent fever (T max 38.6°C). The transthoracic echocardiogram revealed large vegetation on the anterior mitral valve leaflet flopping from the atrial side to the ventricular side. Five sets of blood cultures were positive for coagulase-negative staphylococci. During hospitalization, after two weeks of antibiotic therapy, the patient complained of sudden pain in her right leg associated with numbness. Lower limb arterial Doppler ultrasound showed an arterial thrombosis of right common iliac artery. Transfemoral iliac embolectomy was promptly performed and on septic embolus S. lugdunensis with the same antibiotic sensitivity and the same MIC values was again isolated. Our patient underwent cardiac surgery: triangular resection of the A2 with removal of infected tissue including vegetation. Our case is an example of infective endocarditis by S. lugdunensis on native mitral valve in a young woman of 18 with anamnesis valve prolapse. PMID:23424690

Staphylococcus lugdunensis Endocarditis Complicated by Embolism in an 18-Year-Old Woman with Mitral Valve Prolapse

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Rosaria Pecoraro

2013-01-01

Full Text Available Staphylococcus lugdunensis is a coagulase-negative staphylococcus (CNS. It is a major cause of prosthetic valve endocarditis; mitral valve prolapse (MVP has emerged as a prominent predisposing structural cardiac abnormality. We describe a case of Staphylococcus lugdunensis endocarditis in an 18-year-old woman with preexisting mitral valve prolapse complaining of fever, a one-month history of continuous-remittent fever ( 38.6°C. The transthoracic echocardiogram revealed large vegetation on the anterior mitral valve leaflet flopping from the atrial side to the ventricular side. Five sets of blood cultures were positive for coagulase-negative staphylococci. During hospitalization, after two weeks of antibiotic therapy, the patient complained of sudden pain in her right leg associated with numbness. Lower limb arterial Doppler ultrasound showed an arterial thrombosis of right common iliac artery. Transfemoral iliac embolectomy was promptly performed and on septic embolus S. lugdunensis with the same antibiotic sensitivity and the same MIC values was again isolated. Our patient underwent cardiac surgery: triangular resection of the A2 with removal of infected tissue including vegetation. Our case is an example of infective endocarditis by S. lugdunensis on native mitral valve in a young woman of 18 with anamnesis valve prolapse.

Prevalence of methicillin resistance and macrolide-lincosamide-streptogramin B resistance in Staphylococcus haemolyticus among clinical strains at a tertiary-care hospital in Thailand.

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Teeraputon, S; Santanirand, P; Wongchai, T; Songjang, W; Lapsomthob, N; Jaikrasun, D; Toonkaew, S; Tophon, P

2017-09-01

Staphylococcus spp. is a major cause of nosocomial infection and sepsis. However, increasing drug resistance is becoming a challenge to microbiologists. The purpose of this study was to identify and determine antimicrobial resistance phenotypes and drug resistance genes of clinical coagulase-negative staphylococci (CoNS) isolates at Mae Sot Hospital in Tak province, Thailand. A total of 229 CoNS isolates were collected from clinical specimens during two periods in 2014 and in 2015. Staphylococcus haemolyticus was the most prevalent species (37.55%), followed by S. epidermidis (21.83%), S. saprophyticus (11.79%) and S. hominis (11.35%) respectively. The remaining 17.48% of the organisms comprised S. capitis, S. arlettae, S. cohnii, S. equorum, S. xylosus, S. warneri, S. sciuri, S. pettenkoferi, S. kloosii and S. lugdunensis. Methicillin-resistant CoNS (MRCoNS), containing the mec A gene, were detected in 145 of 229 isolates, mostly found in S. haemolyticus and S. epidermidis. In addition, the differentiation of their macrolide-lincosamide-streptogramin B (MLS B ) resistance phenotypes was determined by the D-test and corresponding resistance genes. Among 125 erythromycin-resistant CoNS, the prevalence of constitutive type of MLS B , inducible clindamycin resistance and macrolide-streptogramin B resistance phenotypes were 72, 13.60 and 14.40% respectively. These phenotypes were expressed in 80% of MRCoNS strains. In addition, the erm C gene (79.20%) was found to be more prevalent than the erm A gene (22.40%), especially among MRCoNS. These results indicate that CoNS may play an important role in spreading of drug resistance genes. More attention to these organisms in surveillance and monitoring programs is needed.

Prevalence of methicillin resistance and macrolide–lincosamide–streptogramin B resistance in Staphylococcus haemolyticus among clinical strains at a tertiary-care hospital in Thailand

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S. Teeraputon

2017-09-01

Full Text Available Staphylococcus spp. is a major cause of nosocomial infection and sepsis. However, increasing drug resistance is becoming a challenge to microbiologists. The purpose of this study was to identify and determine antimicrobial resistance phenotypes and drug resistance genes of clinical coagulase-negative staphylococci (CoNS isolates at Mae Sot Hospital in Tak province, Thailand. A total of 229 CoNS isolates were collected from clinical specimens during two periods in 2014 and in 2015. Staphylococcus haemolyticus was the most prevalent species (37.55%, followed by S. epidermidis (21.83%, S. saprophyticus (11.79% and S. hominis (11.35% respectively. The remaining 17.48% of the organisms comprised S. capitis, S. arlettae, S. cohnii, S. equorum, S. xylosus, S. warneri, S. sciuri, S. pettenkoferi, S. kloosii and S. lugdunensis. Methicillin-resistant CoNS (MRCoNS, containing the mecA gene, were detected in 145 of 229 isolates, mostly found in S. haemolyticus and S. epidermidis. In addition, the differentiation of their macrolide–lincosamide–streptogramin B (MLSB resistance phenotypes was determined by the D-test and corresponding resistance genes. Among 125 erythromycin-resistant CoNS, the prevalence of constitutive type of MLSB, inducible clindamycin resistance and macrolide–streptogramin B resistance phenotypes were 72, 13.60 and 14.40% respectively. These phenotypes were expressed in 80% of MRCoNS strains. In addition, the ermC gene (79.20% was found to be more prevalent than the ermA gene (22.40%, especially among MRCoNS. These results indicate that CoNS may play an important role in spreading of drug resistance genes. More attention to these organisms in surveillance and monitoring programs is needed.

SadA-Expressing Staphylococci in the Human Gut Show Increased Cell Adherence and Internalization.

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Luqman, Arif; Nega, Mulugeta; Nguyen, Minh-Thu; Ebner, Patrick; Götz, Friedrich

2018-01-09

A subgroup of biogenic amines, the so-called trace amines (TAs), are produced by mammals and bacteria and can act as neuromodulators. In the genus Staphylococcus, certain species are capable of producing TAs through the activity of staphylococcal aromatic amino acid decarboxylase (SadA). SadA decarboxylates aromatic amino acids to produce TAs, as well as dihydroxy phenylalanine and 5-hydroxytryptophan to thus produce the neurotransmitters dopamine and serotonin. SadA-expressing staphylococci were prevalent in the gut of most probands, where they are part of the human intestinal microflora. Furthermore, sadA-expressing staphylococci showed increased adherence to HT-29 cells and 2- to 3-fold increased internalization. Internalization and adherence was also increased in a sadA mutant in the presence of tryptamine. The α2-adrenergic receptor is required for enhanced adherence and internalization. Thus, staphylococci in the gut might contribute to gut activity and intestinal colonization. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Microbiological Aetiology, Epidemiology, and Clinical Profile of Prosthetic Joint Infections: Are Current Antibiotic Prophylaxis Guidelines Effective?

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Cheng, Allen C.; Buising, Kirsty L.; Choong, Peter F. M.

2012-01-01

Prosthetic joint infections remain a major complication of arthroplasty. At present, local and international guidelines recommend cefazolin as a surgical antibiotic prophylaxis at the time of arthroplasty. This retrospective cohort study conducted across 10 hospitals over a 3-year period (January 2006 to December 2008) investigated the epidemiology and microbiological etiology of prosthetic joint infections. There were 163 cases of prosthetic joint infection identified. From a review of the microbiological culture results, methicillin-resistant Staphylococcus aureus (MRSA) and coagulase-negative staphylococci were isolated in 45% of infections. In addition, polymicrobial infections, particularly those involving Gram-negative bacilli and enterococcal species, were common (36%). The majority (88%) of patients received cefazolin as an antibiotic prophylaxis at the time of arthroplasty. In 63% of patients in this cohort, the microorganisms subsequently obtained were not susceptible to the antibiotic prophylaxis administered. The results of this study highlight the importance of ongoing reviews of the local ecology of prosthetic joint infection, demonstrating that the spectrum of pathogens involved is broad. The results should inform empirical antibiotic therapy. This report also provokes discussion about infection control strategies, including changing surgical antibiotic prophylaxis to a combination of glycopeptide and cefazolin, to reduce the incidence of infections due to methicillin-resistant staphylococci. PMID:22314530

Comparison of Normal Resident Flora on the Face of Medical Students who use and who do not use Cosmetics

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Udayalaxmi Jeppu

2017-10-01

Full Text Available Introduction: Normal flora of the skin plays a beneficial role in preventing the pathogenic organisms from colonizing the skin and causing infection. It is possible that the facial cosmetics may cause a change in the normal flora disrupting its protective function. Aim: To find out the effect of cosmetics, those that are applied on to the face on resident normal flora of the face. Materials and Methods: This was a cross-sectional study involving medical students aged 19 to 25 years, of whom 42 were regular cosmetic users and another 42 were non cosmetic users. Swabs were taken from the face of the subjects after a face wash with soap and water and eluted in 1 ml sterile peptone water. Tenfold dilutions of the sample were made and 100 ìl of the diluted sample was spread over the surface of Trypticase soy agar, Mac Conkey’s agar and blood agar. The colonies were counted and also identified. Statistical evaluation was done by Chi-square test using SPSS version 16. Results: We isolated Coagulase Negative Staphylococci (CoNS, Micrococcus spp. and methicillin sensitive S.aureus, non-fermenting oxidase negative gram negative bacilli and diphtheroids from both the groups. We found that most of the students who were regular cosmetic users 22 (52.38% yielded negligent growth in comparison with non-cosmetic users (16, 38%. CoNS was less frequently isolated from regular cosmetic users 10 (23.8% in comparison with those who do not use cosmetics 17 (40.47%. Conclusion: It is possible that regular use of cosmetics does reduce the normal flora but further studies with larger sample size are required to prove and confirm this finding.

Antimicrobial susceptibility of quinupristin/dalfopristin tested against gram-positive cocci from Latin America: results from the Global SMART (GSMART surveillance study

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Sader Helio S.

2001-01-01

Full Text Available Gram-positive cocci are important causes of both nosocomial and community-acquired infections, and antimicrobial resistance among these pathogens has become an important problem worldwide. Since resistance among these organisms can vary substantially by geographic location, we conducted a multicenter surveillance study with isolates from five Latin American countries (15 medical centers. Quinupristin/dalfopristin (formerly RP-59500 is a novel streptogramin combination with focused activity against Gram-positive cocci, many exhibiting emerging resistance. The in vitro activity of quinupristin/dalfopristin and 12 other antimicrobial agents were evaluated against 1,948 strains including Staphylococcus aureus (747 strains, coagulase-negative staphylococci (CoNS; 446 strains, enterococci (429 strains, and various Streptococcus spp. (326 strains. Oxacillin resistance was observed in 41% of S. aureus (MIC, or = 13 mm and 40% of CoNS (MIC, or = 18 mm. Vancomycin, teicoplanin, and quinupristin/dalfopristin (MIC90, 0.25 - 1 mug/ml remained effective against all strains, but cross-resistance was high among other tested drugs. The quinupristin/dalfopristin MIC50 for Streptococcus pneumoniae and other streptococci was only 0.5 mug/ml (13% to 28% were penicillin-resistant; 12% to 22% were macrolide-resistant. Enterococci demonstrated variable inhibition by quinupristin/dalfopristin depending upon identification and the susceptibility testing method used. The demonstrated quinupristin/dalfopristin activity against Enterococcus faecium was confirmed, but potential species identification errors with various commercial systems continue to confuse susceptibility statistics, even though some strains of E. faecium confirmed by PCR-based or other molecular identification techniques did have quinupristin/dalfopristin MICs of > or = 4 mug/mL. Most important, glycopeptide-resistant enterococci are rapidly emerging in Latin America, and quinupristin/dalfopristin appears

Evaluation of Coagulase-Positive Staphylococcus Aureus Contamination in Lighvan Cheese on Retail Stores

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Ali Salehi

2014-03-01

Full Text Available Background: Staphylococcus aureus is a Gram-positive, non-sporulated, lack of capsule, immovable, aerobic and anaerobic and able to tolerate high levels of salt (up to 15 percent. Therefore, foods containing salt provides an ideal environment for bacterial growth. It is also one of the most important bacterial born of spoilable food products, especially in dairy products. Lighvan traditional cheese is consumed in many regions of Iran, especially consumption of these cheeses is very high in Tehran which in the manufacture of such cheeses, the unpasteurized and raw milk is used and the sanitary conditions during processing and subsequent storage are low. So, considering the importance of this issue in the release of poisoning, the coagulase-positive Staphylococcus aureus contamination in Lighvan cheese on Retail Stores was evaluated. Materials and Methods: In order to perform this study, 22 samples of traditional Lighvan cheese were collected randomly from Tehran stores and according to Iran national standards and by using of bird-parker, Cook Meat cultures and coagulase test were evaluated. Results: Total of 22 samples, 14 samples (63/6% were contaminated by S. aureus over standard and 5 (22/7% were contaminated with Staphylococcus aureus coagulase positive. Conclusion: This study demonstrated that sanitary conditions should be observed during the production and Use of pasteurized milk in cheese production.

Screening Antibacterial Agent from Crude Extract of Marine-Derived Fungi Associated with Soft Corals against MDR-Staphylococcus haemolyticus

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Sabdaningsih, A.; Cristianawati, O.; Sibero, M. T.; Nuryadi, H.; Radjasa, O. K.; Sabdono, A.; Trianto, A.

2017-02-01

Multidrug resistant Staphylococcus haemolyticus is a Gram-positive bacteria and member of coagulase negative staphylococci (CoNS) which has the highest level of antimicrobial resistance. This nosocomial pathogen due to skin or soft tissue infections, bacteremia, septicemia, peritonitis, otitis media, meningitis and urinary tract infections. The ability to produce enterotoxins, hemolysins, biofilm, and cytotoxins could be an important characteristic for the successful of infection. Marine-derived fungi have potency as a continuous supply of bioactive compound. The aim of this research was screening antibacterial agent from crude extracts of marine-derived fungi associated with soft corals against MDR-S. haemolyticus. Among 23 isolates of marine-derived fungi isolated from 7 soft corals, there were 4 isolates active against MDR-S. haemolyticus. The screening was conducted by using agar plug diffusion method. Isolate PPSC-27-A4 had the highest antibacterial activity with diameter 23±9,6 mm. The crude extract from this isolate had been confirmed to antibacterial susceptibility test and it had the highest antibacterial activity in 12.2 mm with concentration of 300μg/ml from mycelia extract. PPSC-27-A4 had been characterized in molecular, based on the sequence analysis of 18S rRNA, PPSC-27-A4 isolate was identified as Trichoderma longibrachiatum.

Kits para aerossol em um serviço de saúde: uma análise microbiológica após reprocessamento Kits para aerosol en un servicio de salud: un análisis microbiológico post procesamiento Aerosol kits in a health service: a post-processing microbiologic analysis

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Patrícia Staciarini Anders

2008-06-01

. Se aisló un total de 101 UFC, 39 provenientes de los vasos, 20 de las extensiones y 42 de las máscaras. Entre los patógenos aislados se destacan: Staphylococcus coagulase positivo, Staphylococcus coagulase negativo, Bastones Gram negativo fermentadores, Bastones Gram negativo no fermentadores, micrococosy levaduras. La detección microbiológica indica probables fallas en el reprocesamiento de esos artículos.Aerosol kits are used in treatments of respiratory illnesses and require at least an intermediate level of disinfection for their reuse. The objectives of the study were to verify possible contamination of kits after they were processed as well as to identify the microorganisms that were isolated in them. This transversal experimental study was conducted in the pediatric unit of a hospital in Goiânia, State of Goiás. Samples were collected from three different parts (masks, cups and hoses of 15 previously disinfected kits and placed in different culture media, and the microorganisms that were isolated were identified through biochemical tests. Of the kits that were analyzed, 13 cups, 9 hoses and 13 masks were found to be contaminated. A total of 101 CFU were isolated 39 from the cups, 20 from the hoses, and 42 the masks. Among the pathogens found were coagulase-positive Staphylococci, coagulase-negative Staphylococci, Gram negative fermenter rods, Gram negative nonfermenter rods, micrococcus and yeast. Microbial presence indicates probable inefficiencies in processing these items.

In vitro activity of ceftaroline against staphylococci from prosthetic joint infection.

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Park, Kyung-Hwa; Greenwood-Quaintance, Kerryl E; Patel, Robin

2016-02-01

We tested the in vitro activity of ceftaroline by Etest against staphylococci recovered from patients with prosthetic joint infection, including 97 Staphylococcus aureus isolates (36%, oxacillin resistant) and 74 Staphylococcus epidermidis isolates (74%, oxacillin resistant). Ceftaroline inhibited all staphylococci at ≤0.5 μg/mL. The ceftaroline MIC(90/50) values for methicillin-susceptible S. aureus, methicillin-susceptible S. epidermidis, methicillin-resistant S. aureus, and methicillin-resistant S. epidermidis were 0.19/0.125, 0.094/0.047, 0.5/0.38, and 0.38/0.19 μg/mL, respectively. Based on these in vitro findings, ceftaroline should be further evaluated as a potential therapeutic option for the treatment of prosthetic joint infection caused by methicillin-susceptible and methicillin-resistant S. aureus and S. epidermidis. Copyright © 2016 Elsevier Inc. All rights reserved.

Outcomes of single organism peritonitis in peritoneal dialysis: gram negatives versus gram positives in the Network 9 Peritonitis Study.

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Bunke, C M; Brier, M E; Golper, T A

1997-08-01

The use of the "peritonitis rate" in the management of patients undergoing peritoneal dialysis is assuming importance in comparing the prowess of facilities, care givers and new innovations. For this to be a meaningful outcome measure, the type of infection (causative pathogen) must have less clinical significance than the number of infections during a time interval. The natural history of Staphylococcus aureus, pseudomonas, and fungal peritonitis would not support that the outcome of an episode of peritonitis is independent of the causative pathogen. Could this concern be extended to other more frequently occurring pathogens? To address this, the Network 9 Peritonitis Study identified 530 episodes of single organism peritonitis caused by a gram positive organism and 136 episodes caused by a single non-pseudomonal gram negative (NPGN) pathogen. Coincidental soft tissue infections (exit site or tunnel) occurred equally in both groups. Outcomes of peritonitis were analyzed by organism classification and by presence or absence of a soft tissue infection. NPGN peritonitis was associated with significantly more frequent catheter loss, hospitalization, and technique failure and was less likely to resolve regardless of the presence or absence of a soft tissue infection. Hospitalization and death tended to occur more frequently with enterococcal peritonitis than with other gram positive peritonitis. The outcomes in the NPGN peritonitis group were significantly worse (resolution, catheter loss, hospitalization, technique failure) compared to coagulase negative staphylococcal or S. aureus peritonitis, regardless of the presence or absence of a coincidental soft tissue infection. Furthermore, for the first time, the poor outcomes of gram negative peritonitis are shown to be independent of pseudomonas or polymicrobial involvement or soft tissue infections. The gram negative organism appears to be the important factor. In addition, the outcome of peritonitis caused by S. aureus

Bacterial recolonization of the skin and wound contamination during cardiac surgery: a randomized controlled trial of the use of plastic adhesive drape compared with bare skin.

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Falk-Brynhildsen, K; Söderquist, B; Friberg, O; Nilsson, U G

2013-06-01

Sternal wound infection after cardiac surgery is a serious complication. Various perioperative strategies, including plastic adhesive drapes, are used to reduce bacterial contamination of surgical wounds. To compare plastic adhesive drape to bare skin regarding bacterial growth in wound and time to recolonization of the adjacent skin intraoperatively, in cardiac surgery patients. This single-blinded randomized controlled trial (May 2010 to May 2011) included 140 patients scheduled for cardiac surgery via median sternotomy. The patients were randomly allocated to the adhesive drape (chest covered with plastic adhesive drape) or bare skin group. Bacterial samples were taken preoperatively and intraoperatively every hour during surgery until skin closure. Disinfection with 0.5% chlorhexidine solution in 70% alcohol decreased coagulase-negative staphylococci (CoNS), while the proportion colonized with Propionibacterium acnes was not significantly reduced and was still present in more than 50% of skin samples. P. acnes was significantly more common in men than in women. Progressive bacterial recolonization of the skin occurred within 2-3 h. At 120 min there were significantly more positive cultures in the adhesive drape group versus bare skin group for P. acnes (63% vs 44%; P = 0.034) and for CoNS (45% vs 24%; P = 0.013). The only statistically significant difference in bacterial growth in the surgical wound was higher proportion of CoNS at the end of surgery in the adhesive drape group (14.7% vs 4.4%; P = 0.044). Plastic adhesive drape does not reduce bacterial recolonization. P. acnes colonized men more frequently, and was not decreased by disinfection with chlorhexidine solution in alcohol. Copyright © 2013 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Neonatal nosocomial sepsis in a level-III NICU: evaluation of the causative agents and antimicrobial susceptibilities.

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Yalaz, Mehmet; Cetin, Hasan; Akisu, Mete; Aydemir, Söhret; Tunger, Alper; Kültürsay, Nilgün

2006-01-01

Despite advances in supportive care and use of antibiotics, sepsis preserves its importance due to its high mortality and morbidity for neonates. Identifying the causative agents and antibiotic resistance yearly in a neonatal intensive care unit (NICU) helps the physician to choose the most appropriate empirical therapy. In this study we aimed to evaluate positive blood cultures and antibiotic susceptibilities of newborns with proven sepsis during the years 2000-2002 in our NICU. The charts of babies with sepsis were evaluated for clinical characteristics, positive cultures and antimicrobial susceptibilities, retrospectively. Although most of the admitted patients were premature (76.5%), the frequency of proven sepsis was quite low, at 9.1% among 909 newborns. Mortality rate in sepsis was 16%. The most commonly isolated micro-organisms were coagulase-negative staphylococci (CoNS) (31.3%), fungi (19.2%), Staphylococcus aureus (13%) and Klebsiella pneumoniae (10.5%). Methicillin resistance for CoNS was 92.3% and for S. aureus was 72.7%. In the last year, a significant increase in the frequency of Klebsiella pneumoniae (8.3 vs 14.2%), CoNS (27.1 vs 37.1%), Pseudomonas aeruginosa (2.1 vs 8.6%) and fungal infections (18.8 vs 20%) was observed compared to the previous years. An initial empirical antibiotic therapy for late-onset sepsis was designed with teicoplanin + piperacillin-tazobactam/meropenem + antifungal (fluconazole or amphotericin B) as the best combination to cover this spectrum until the culture results arrive. However, this combination is only compatible with our results and may not be applied in all units. Every unit must follow the bacterial spectrum and antibacterial resistance patterns to choose their specific empirical treatment strategy for nosocomial infections.

Effects of environmental modification on mastitis occurrence and hormonal changes in Holstein cows

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Juliana R.P. Arcaro

2013-06-01

Full Text Available The purpose of this research was to evaluate the effects of evaporative cooling in freestall on mastitis occurrence, milk production, and composition, as well as cortisol, T3 (triiodothyronine, and T4 (thyroxin levels in lactating dairy cows. Twenty-eight multiparous cows averaging 70 ± 10 day postpartum were used in four treatments from January to March 2003. The treatments were: Day (cooling from 7:00 a.m. to 7:00 p.m.; Night (cooling from 7:00 p.m. to 7:00 a.m.; 24-hour (cooling 24-hour; and Control (no cooling. Wired cup test was used for clinical mastitis diagnosis, and the California Mastitis Test (CMT was used to identify subclinical mastitis. Blood and milk samples were taken weekly for microbiological and hormonal analyses. The cortisol levels were higher than normal values in all treatment groups, suggesting stress conditions, but T3 and T4 levels remained normal in all groups. The occurrence of subclinical mastitis was lower in Day and Night groups than in Control and 24-hour groups. Regarding the microbiological analyses, in all groups the isolation of Corynebacterium sp. from milk samples increased while negative coagulase staphylococci (CNS declined as etiological agents of subclinical mastitis. However, in Day and 24-hour groups, coagulase positive staphylococci (CPS increased mainly Staphylococcus aureus (49.8% and 47.7% respectively. The Night group showed a decrease in subclinical mastitis occurrences. Our data indicate that all animals subjected to treatments presented high levels of cortisol, indicating a stress condition. The Night treatment presented a reduction in microbial isolation, suggesting a reduced susceptibility to mastitis.

Adherence of Staphylococci to plastic, mesothelial cells and mesothelial extracellular matrix

NARCIS (Netherlands)

Betjes, M. G.; Tuk, C. W.; Struijk, D. G.; Krediet, R. T.; Arisz, L.; Beelen, R. H.

1992-01-01

In this study we have investigated whether mesothelial cells (MC) and mesothelial extracellular matrix (ECM) are suitable substrates for the adherence of Staphylococci. Mesothelial cells were isolated from the peritoneal dialysis effluent by making use of their lack of Fc-receptors and capacity to

Detecção da produção de slime por estafilococos coagulase-negativa isolados de cateter venoso central

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E. L. Pizzolitto

2009-01-01

Full Text Available

A produção de slime é um importante fator de virulência dos estafilococos coagulase-negativa, permitindo-lhes aderir sobre as superfícies lisas de biomateriais, e por isso, é associada aos processos de infecção de implantes. No presente estudo a produção de slime em 27 cepas de estafilococos coagulase-negativa foi investigada por cultura em ágar vermelho Congo (77,7% de positividade, método espectrofotométrico ou da microplaca (81,4% de positividade e microscopia eletrônica de varredura (88,9% de positividade. Foi também avaliada a resistência de estafilococos coagulasenegativa a vários antimicrobianos usando a técnica do disco difusão. A porcentagem de resistência à penicilina G, oxacilina, eritromicina, clindamicina e gentamicina em estafilococos produtores de slime foi respectivamente de 88,9%; 70,4%; 81,5%; 66,7% e 59,2%; todos os estafilococos coagulase-negativa foram vancomicina sensíveis. As cepas isoladas de cateter venoso central foram identificadas por método convencional e sistema API Staph. Os 27 estafilococos coagulase-negativa foram identificados como: S. saprophyticus (3,7%, S. xylosus (7,4%, S. haemolyticus (14,8%, S. epidermidis (37,0%, S. warneri (14,8%, S. lugdunensis (7,4%, S. hominis (7,4%, S. schleiferi (3,7% e S. chromogenes (3,7%. Pode-se concluir que entre a maioria das espécies Staphylococcus coagulase-negativa houve associação entre a produção de slime, origem nosocomial das cepas e reduzida sensibilidade aos antimicrobianos, sugerindo potencial patogênico no ambiente hospitalar. Palavras-chave: estafilococos coagulase-negativa; slime; fatores de virulência; polissacarídeo extracelular; biofilme; sensibilidade aos antimicrobianos.

Identification of methicillin-resistant Staphylococcus aureus (MRSA) strains isolated from burn patients by multiplex PCR.

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Montazeri, Effat Abbasi; Khosravi, Azar Dokht; Jolodar, Abbas; Ghaderpanah, Mozhgan; Azarpira, Samireh

2015-05-01

Methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase-negative staphylococci (MRCoNS) as important human pathogens are causes of nosocomial infections worldwide. Burn patients are at a higher risk of local and systemic infections with these microorganisms. A screening method for MRSA by using a multiplex polymerase chain reaction (PCR) targeting the 16S ribosomal RNA (rRNA), mecA, and nuc genes was developed. The aim of the present study was to investigate the potential of this PCR assay for the detection of MRSA strains in samples from burn patients. During an 11-month period, 230 isolates (53.11%) of Staphylococcus spp. were collected from burn patients. The isolates were identified as S. aureus by using standard culture and biochemical tests. DNA was extracted from bacterial colonies and multiplex PCR was used to detect MRSA and MRCoNS strains. Of the staphylococci isolates, 149 (64.9%) were identified as S. aureus and 81 (35.21%) were described as CoNS. Among the latter, 51 (62.97%) were reported to be MRCoNS. From the total S. aureus isolates, 132 (88.6%) were detected as MRSA and 17 (11.4%) were methicillin-susceptible S. aureus (MSSA). The presence of the mecA gene in all isolates was confirmed by using multiplex PCR as a gold standard method. This study presented a high MRSA rate in the region under investigation. The 16S rRNA-mecA-nuc multiplex PCR is a good tool for the rapid characterization of MRSA strains. This paper emphasizes the need for preventive measures and choosing effective antimicrobials against MRSA and MRCoNS infections in the burn units. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

Evaluation of pet contact as a risk factor for carriage of multidrug-resistant staphylococci in nursing home residents.

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Gandolfi-Decristophoris, Paola; De Benedetti, Anna; Petignat, Christiane; Attinger, Monica; Guillaume, Jan; Fiebig, Lena; Hattendorf, Jan; Cernela, Nicole; Regula, Gertraud; Petrini, Orlando; Zinsstag, Jakob; Schelling, Esther

2012-03-01

Pets, often used as companionship and for psychological support in the therapy of nursing home residents, have been implicated as reservoirs for antibiotic-resistant bacteria. We investigated the importance of pets as reservoirs of multidrug-resistant (MDR) staphylococci in nursing homes. We assessed the carriage of MDR staphylococci in pets and in 2 groups of residents, those living in nursing homes with pets and those living without pet contacts. We collected demographic, health status, and human-pet contact data by means of questionnaires. We assessed potential bacteria transmission pathways by investigating physical resident-to-pet contact. The observed prevalence of MDR staphylococci carriage was 84/229 (37%) in residents living with pets and 99/216 (46%) in those not living with pets (adjusted odds ratio [aOR], 0.6; 95% confidence interval [CI], 0.4-0.9). Active pet contact was associated with lower carriage of MDR staphylococci (aOR, 0.5; 95% CI, 0.4-0.8). Antibiotic treatment during the previous 3 months was associated with significantly increased risk for MDR carriage in residents (aOR, 3.1; 95% CI, 1.8-5.7). We found no evidence that the previously reported benefits of pet contact are compromised by the increased risk of carriage of MDR staphylococci in residents associated with interaction with these animals in nursing homes. Thus, contact with pets, always under good hygiene standards, should be encouraged in these settings. Copyright © 2012 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

Microbiologic study of soft contact lenses after laser subepithelial keratectomy for myopia.

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Hondur, Ahmet; Bilgihan, Kamil; Cirak, Meltem Yalinay; Dogan, Ozgur; Erdinc, Alper; Hasanreisoglu, Berati

2008-01-01

To evaluate the extent and agents of bacterial contamination of bandage disposable soft contact lenses after laser subepithelial keratectomy (LASEK) and to correlate the findings with clinical data. Disposable soft contact lenses were collected from 52 eyes of 26 consecutive patients treated with LASEK for myopia. The patients were treated with a fixed combination of tobramycin and diclofenac until epithelial closure. The lenses were removed on the fourth or fifth postoperative day with sterile forceps and immediately placed in sterile tubes containing culture media brain-heart infusion broth. The lenses were evaluated for microbial colonization. Of the 52 contact lenses analyzed, six (11.5%) had positive cultures. However, no clinical finding of infection was noted. Isolated microorganisms were coagulase-negative staphylococci (two lenses), Stenotrophomonas maltophilia (two lenses), Acinetobacter species (one lens), and Aeromonas hydrophila (one lens). Except for one case, the microorganisms were sensitive to the administered antibiotic. The risk of infectious keratitis after LASEK seems to be low. Except for staphylococci, the isolated microorganisms have not been previously reported to colonize the ocular surface or cause keratitis after refractive surgery. These findings may suggest a changing trend of potentially infectious agents after surface ablation.

Diversity of staphylococcal cassette chromosome mec structures in methicillin-resistant Staphylococcus epidermidis and Staphylococcus haemolyticus strains among outpatients from four countries.

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Ruppé, Etienne; Barbier, François; Mesli, Yasmine; Maiga, Aminata; Cojocaru, Radu; Benkhalfat, Mokhtar; Benchouk, Samia; Hassaine, Hafida; Maiga, Ibrahim; Diallo, Amadou; Koumaré, Abdel Karim; Ouattara, Kalilou; Soumaré, Sambou; Dufourcq, Jean-Baptiste; Nareth, Chhor; Sarthou, Jean-Louis; Andremont, Antoine; Ruimy, Raymond

2009-02-01

In staphylococci, methicillin (meticillin) resistance (MR) is mediated by the acquisition of the mecA gene, which is carried on the size and composition variable staphylococcal cassette chromosome mec (SCCmec). MR has been extensively studied in Staphylococcus aureus, but little is known about MR coagulase-negative staphylococci (MR-CoNS). Here, we describe the diversity of SCCmec structures in MR-CoNS from outpatients living in countries with contrasting environments: Algeria, Mali, Moldova, and Cambodia. Their MR-CoNS nasal carriage rates were 29, 17, 11, and 31%, respectively. Ninety-six MR-CoNS strains, comprising 75 (78%) Staphylococcus epidermidis strains, 19 (20%) Staphylococcus haemolyticus strains, 1 (1%) Staphylococcus hominis strain, and 1 (1%) Staphylococcus cohnii strain, were analyzed. Eighteen different SCCmec types were observed, with 28 identified as type IV (29%), 25 as type V (26%), and 1 as type III (1%). Fifteen strains (44%) were untypeable for their SCCmec. Thirty-four percent of MR-CoNS strains contained multiple ccr copies. Type IV and V SCCmec were preferentially associated with S. epidermidis and S. haemolyticus, respectively. MR-CoNS constitute a widespread and highly diversified MR reservoir in the community.

Occurance of Staphylococcus nepalensis strains in different sources including human clinical material.

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Nováková, Dana; Pantůcek, Roman; Petrás, Petr; Koukalová, Dagmar; Sedlácek, Ivo

2006-10-01

Five isolates of coagulase-negative staphylococci were obtained from human urine, the gastrointestinal tract of squirrel monkeys, pig skin and from the environment. All key biochemical characteristics of the tested strains corresponded with the description of Staphylococcus xylosus species. However, partial 16S rRNA gene sequences obtained from analysed strains corresponded with those of Staphylococcus nepalensis reference strains, except for two strains which differed in one residue. Ribotyping with EcoRI and HindIII restriction enzymes, whole cell protein profile analysis performed by SDS-PAGE and SmaI macrorestriction analysis were used for more precise characterization and identification of the analysed strains. Obtained results showed that EcoRI and HindIII ribotyping and whole cell protein fingerprinting are suitable and reliable methods for the differentiation of S. nepalensis strains from the other novobiocin resistant staphylococci, whereas macrorestriction analysis was found to be a good tool for strain typing. The isolation of S. nepalensis is sporadic, and according to our best knowledge this study is the first report of the occurrence of this species in human clinical material as well as in other sources.

Antibacterial susceptibility profiles of subclinical mastitis pathogens isolated in Batna and Setif Governorates (East of Algeria

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Mamache Bakir

Full Text Available Sub-clinical mastitis is a main pathology of dairy husbandry because it is not clinically recognized by the owners and the veterinarians. For this reason, its economic loss is usually underestimated in milk production. This study has been undertaken in order to evaluate the epidemiologic situation of sub-clinicalmastitis in Batna and Setif governorates (East of Algeria. For this purpose, a detailed bacteriological study of all bacterial strains isolated from sub-clinical mastitis followed by a study of their antibacterial susceptibility profiles has been undertaken. 89 bacterial strains distributed as follows were studied: 27 strains of staphylococci among which 23 were coagulase-negative staphylococci (CNS that are generally incriminated in sub-clinical mastitis. 39 strains of streptococci among which 10 were Lactococcus lactis ssp lactis strains. 23 strains of enterobacteria represented mainly by Escherichia coli (E.coli. All these bacterial strains were isolated from cow milk of 3 different farms. The antibacterial susceptibility profiles have revealed a susceptibility of the isolated strains to a large number of antibiotics mainly to the Neomycin, the Cephalexin and the Spiramycin. [Vet. World 2011; 4(12.000: 537-541

Bovine-associated CNS species resist phagocytosis differently

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2013-01-01

Background Coagulase-negative staphylococci (CNS) cause usually subclinical or mild clinical bovine mastitis, which often remains persistent. Symptoms are usually mild, mostly only comprising slight changes in the appearance of milk and possibly slight swelling. However, clinical mastitis with severe signs has also been reported. The reasons for the differences in clinical expression are largely unknown. Macrophages play an important role in the innate immunity of the udder. This study examined phagocytosis and killing by mouse macrophage cells of three CNS species: Staphylococcus chromogenes (15 isolates), Staphylococcus agnetis (6 isolates) and Staphylococcus simulans (15 isolates). Staphylococcus aureus (7 isolates) was also included as a control. Results All the studied CNS species were phagocytosed by macrophages, but S. simulans resisted phagocytosis more effectively than the other CNS species. Only S. chromogenes was substantially killed by macrophages. Significant variations between isolates were seen in both phagocytosis and killing by macrophages and were more common in the killing assays. Significant differences between single CNS species and S. aureus were observed in both assays. Conclusion This study demonstrated that differences in the phagocytosis and killing of mastitis-causing staphylococci by macrophages exist at both the species and isolate level. PMID:24207012

Competing for Iron: Duplication and Amplification of the isd Locus in Staphylococcus lugdunensis HKU09-01 Provides a Competitive Advantage to Overcome Nutritional Limitation.

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Heilbronner, Simon; Monk, Ian R; Brozyna, Jeremy R; Heinrichs, David E; Skaar, Eric P; Peschel, Andreas; Foster, Timothy J

2016-08-01

Staphylococcus lugdunensis is a coagulase negative bacterial pathogen that is particularly associated with severe cases of infectious endocarditis. Unique amongst the coagulase-negative staphylococci, S. lugdunensis harbors an iron regulated surface determinant locus (isd). This locus facilitates the acquisition of heme as a source of nutrient iron during infection and allows iron limitation caused by "nutritional immunity" to be overcome. The isd locus is duplicated in S. lugdunensis HKU09-01 and we show here that the duplication is intrinsically unstable and undergoes accordion-like amplification and segregation leading to extensive isd copy number variation. Amplification of the locus increased the level of expression of Isd proteins and improved binding of hemoglobin to the cell surface of S. lugdunensis. Furthermore, Isd overexpression provided an advantage when strains were competing for a limited amount of hemoglobin as the sole source of iron. Gene duplications and amplifications (GDA) are events of fundamental importance for bacterial evolution and are frequently associated with antibiotic resistance in many species. As such, GDAs are regarded as evolutionary adaptions to novel selective pressures in hostile environments pointing towards a special importance of isd for S. lugdunensis. For the first time we show an example of a GDA that involves a virulence factor of a Gram-positive pathogen and link the GDA directly to a competitive advantage when the bacteria were struggling with selective pressures mimicking "nutritional immunity".

Fulminant Staphylococcus lugdunensis septicaemia following a pelvic varicella-zoster virus infection in an immune-deficient patient: a case report

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Woznowski M

2010-09-01

Full Text Available Abstract Introduction The deadly threat of systemic infections with coagulase negative Staphylococcus lugdunensis despite an appropriate antibiotic therapy has only recently been recognized. The predominant infectious focus observed so far is left-sided native heart valve endocarditis, but bone and soft tissue infections, septicaemia and vascular catheter-related bloodstream infections have also been reported. We present a patient with a fatal Staphylococcus lugdunensis septicaemia following zoster bacterial superinfection of the pelvic region. Case presentation A 71-year old male diagnosed with IgG kappa plasmocytoma presented with a conspicuous weight loss, a hypercalcaemic crisis and acute renal failure. After initiation of haemodialysis treatment his condition improved rapidly. However, he developed a varicella-zoster virus infection of the twelfth thoracic dermatome requiring intravenous acyclovir treatment. Four days later the patient presented with a fulminant septicaemia. Despite an early intravenous antibiotic therapy with ciprofloxacin, piperacillin/combactam and vancomycin the patient died within 48 hours, shortly before the infective isolate was identified as Staphylococcus lugdunensis by polymerase chain reaction. Conclusion Despite S. lugdunensis belonging to the family of coagulase-negative staphylococci with an usually low virulence, infections with S. lugdunensis may be associated with an aggressive course and high mortality. This is the first report on a Staphylococcus lugdunensis septicaemia following a zoster bacterial superinfection of the pelvic region.

Molecular typing of Staphylococcus aureus based on coagulase gene.

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Javid, Faizan; Taku, Anil; Bhat, Mohd Altaf; Badroo, Gulzar Ahmad; Mudasir, Mir; Sofi, Tanveer Ahmad

2018-04-01

This study was conducted to study the coagulase gene-based genetic diversity of Staphylococcus aureus , isolated from different samples of cattle using restriction fragment length polymorphism (RFLP) and their sequence-based phylogenetic analysis. A total of 192 different samples from mastitic milk, nasal cavity, and pus from skin wounds of cattle from Military Dairy Farm, Jammu, India, were screened for the presence of S. aureus . The presumptive isolates were confirmed by nuc gene-based polymerase chain reaction (PCR). The confirmed S. aureus isolates were subjected to coagulase ( coa ) gene PCR. Different coa genotypes observed were subjected to RFLP using restriction enzymes Hae111 and Alu1 , to obtain the different restriction patterns. One isolate from each restriction pattern was sequenced. These sequences were aligned for maximum homology using the Bioedit softwareandsimilarity in the sequences was inferred with the help of sequence identity matrix. Of 192 different samples,39 (20.31%) isolates of S. aureus were confirmed by targeting nuc gene using PCR. Of 39 S. aureus isolates, 25 (64.10%) isolates carried coa gene. Four different genotypes of coa gene, i.e., 514 bp, 595 bp, 757 bp, and 802 bp were obtained. Two coa genotypes, 595 bp (15 isolates) and 802 bp (4 isolates), were observed in mastitic milk. 514 bp (2 isolates) and 757 bp (4 isolates) coa genotypes were observed from nasal cavity and pus from skin wounds, respectively. On RFLP using both restriction enzymes, four different restriction patterns P1, P2, P3, and P4 were observed. On sequencing, four different sequences having unique restriction patterns were obtained. The most identical sequences with the value of 0.810 were found between isolate S. aureus 514 (nasal cavity) and S. aureus 595 (mastitic milk), and thus, they are most closely related. While as the most distant sequences with the value of 0.483 were found between S. aureus 514 and S. aureus 802 isolates. The study, being localized

MICROBIOLOGICAL AND PARASITOLOGICAL QUALITY OF “PANGA FISH" (PANGASIUS SPP.

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E. E. V. Resplandes

2017-12-01

Full Text Available The goals of the study were to verify the presence of coliforms in frozen Basa fish fillets market in different cities in Mato Grosso State, Brazil and identify if they complied with the standards established by the Brazilian Food Legislation. Twenty-five samples were collected at supermarkets in eight cities in Mato Grosso State. The microbiological analyses were performed using the coagulase-positive Staphylococci count; screening for Salmonella sp., enumeration of total coliforms, thermotolerant and Escherichia coli. In addition, it proceeded to parasitological analysis by parasitic morphological structures identification. Coagulase-positive Staphylococci strains were isolated in two samples (8% with 3,8 x 10 4 and 1,4 x 10 5 CFU/g. In one sample (4%, the values obtained were 23 MPN/ g for total coliforms count, 4 MPN/ g for thermotolerant coliforms and 4 MPN/ g for E. coli. Salmonella spp. strains were not isolated. Parasitic structures were not observed. Frozen Panga fish fillets demonstrated low levels of coliform contamination; indicating that it is safe for human consumption considering that 23 (92% of the analyzed samples were within the standards established by the current Brazilian Food Legislation.

Associations of selected bedding types with incidence rates of subclinical and clinical mastitis in primiparous Holstein dairy cows.

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Rowbotham, R F; Ruegg, P L

2016-06-01

The objective of this observational study was to determine the association of exposure to selected bedding types with incidence of subclinical (SM) and clinical mastitis (CM) in primiparous Holstein dairy cows housed in identical pens at a single facility. At parturition, primiparous cows were randomly assigned to pens containing freestalls with 1 of 4 bedding materials: (1) deep-bedded new sand (NES, n=27 cows), (2) deep-bedded recycled sand (RS, n=25 cows), (3) deep-bedded manure solids (DBMS, n=31 cows), and (4) shallow-bedded manure solids over foam-core mattresses (SBMS, n=26 cows). For 12mo, somatic cell counts of quarter milk samples were determined every 28d and duplicate quarter milk samples were collected for microbiological analysis from all quarters with SM (defined as somatic cell count >200,000 cells/mL). During this period, duplicate quarter milk samples were also collected for microbial analysis from all cases of CM. For an additional 16mo, cases of CM were recorded; however, no samples were collected. Quarter days at risk (62,980) were distributed among bedding types and most quarters were enrolled for >150d. Of 135 cases of SM, 63% resulted in nonsignificant growth and 87% of recovered pathogens (n=33) were identified as coagulase-negative staphylococci. The distribution of etiologies of pathogens recovered from cases of SM was associated with bedding type. Coagulase-negative staphylococci were recovered from 12, 38, 11, and 46% of quarters with SM from cows in pens containing NES, RS, DBMS, and SBMS, respectively. A result of nonsignificant growth was obtained for 81, 59, 89, and 46% of quarters with SM from cows in pens containing NES, RS, DBMS, and SBMS, respectively. Quarters of primiparous cows bedded with NES tended to have greater survival time to incidence of CM than quarters of primiparous cows bedded with RS or DBMS. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Endophthalmitis caused by gram-positive bacteria resistant to vancomycin: Clinical settings, causative organisms, antimicrobial susceptibilities, and treatment outcomes

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Hegde Sharat Shivaramaiah

2018-06-01

Full Text Available Purpose: To report the clinical settings, causative organisms, antimicrobial susceptibilities, and treatment outcomes of patients with endophthalmitis caused by gram-positive bacteria resistant to vancomycin. Methods: Retrospective case series of all patients with culture-proven endophthalmitis caused by gram-positive bacteria resistant to vancomycin between January 2010 and December 2016 in LV Prasad Eye Institute, Visakhapatnam, India. Results: The current study included 14 patients. The clinical settings were post-cataract surgery in 8/14 (57.1% and open globe injury in 6/14 (42.8%. Primary intervention for all patients included tap and intravitreal antibiotic injection. During subsequent follow-up, pars plana vitrectomy was performed in 6 patients and one patient underwent penetrating keratoplasty. Mean number of intravitreal antibiotic injections performed were 3.4 per patient. The most common organisms isolated were coagulase-negative Staphylococci in 6/14 (42.8%, Staphylococcus aureus in 5/14 (35.7%, Streptococcus sp in 2/14 (14.2% and Bacillus sp in 1/14 (7.14%. In addition to vancomycin, resistance to multiple drugs (three or more groups of antibiotics was found in all 14 cases. Antimicrobial susceptibility results showed susceptibility to amikacin in 7/14 (50.0%, gatifloxacin in 6/14 (42.8%, moxifloxacin in 3/13 (23.0%, cefazoline in 5/14 (35.7%, cefuroxime in 3/14 (21.4%, ciprofloxacin in 2/14 (14.2% and linezolid in 5/5 (100%. The mean duration of follow-up was 30.7 weeks (6 weeks–90 weeks. At last follow-up, visual acuity (VA of 20/200 or better was recorded in 7/14 (50% and VA < 5/200 occurred in 7/14 (50%. Conclusion and importance: Antimicrobial susceptibility testing may help in selection of suitable antimicrobial agents for repeat intravitreal injection. Inspite of retreatment with intravitreal antibiotics, these patients generally had poor VA outcomes. Keywords: Coagulase-negative Staphylococci, Endophthalmitis

Microbiological analysis and sensitivity profile of Staphylococcus spp. in subclinical mastitis of dairy goats

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S.R.S. Salaberry

2016-04-01

Full Text Available Subclinical mastitis in goats causes economic losses and risks to public health. Given the need for research that shows the most isolated staphylococci species and sensibility tests comparing the resistance between coagulase-negative (CNS and positive Staphylococcus (CPS goats with subclinical mastitis, the aim of this study was to identify the microorganisms isolated from milk samples of goats with subclinical mastitis, as well as define the staphylococci species and determine the sensitivity profile of Staphylococcus spp. to antimicrobials. To collect samples, tests were performed for mug of black background and California mastitis test (CMT, collecting milk from CMT positive animals. A total of 226 samples from seven herds of dairy goats was collected and forwarded to the laboratory, where they were seeded for the isolation of the microorganism and implementing the antibiotic sensibility test. Of these, 122 samples had bacterial growth and the most isolated staphylococci species were: S. epidermidis (24.55%, S. lugdunensis (15.40% and S. intermedius (13.64%. Samples showed increased resistance to antimicrobials: penicillin (81.8%, oxacillin (60.0% and ampicillin (55.5%. Greater sensitivity to: enrofloxacin (99.1%, erythromycin (98.2%, gentamicin (98.2% and vancomycin (98.2% were observed. The S. epidermidis showed higher antimicrobial resistance to amoxicillin and penicillin than S. lugdunensis and S. intermedius. Similar resistance in vitro between CNS and CPS was observed to most antimicrobials. It is important to control the overuse of antibiotics to prevent the emergence of resistant strains.

Root cause analysis of methicillin resistant Staphylococcus aureus bacteraemia.

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Aslam, Nadia; Mehdi, Naima; Izhar, Mateen

2015-10-01

To find the important risk factors and sources of bacteraemia in patients suffering from methicillin-resistant staphylococcus aureus bacteraemia. The descriptive study was carried out at Shaikh Zayed Hospital, Lahore, from October 2010 to August 2011. Blood cultures were processed to isolate methicillin-resistant staphylococcus aureus. A questionnaire was completed by the participating patients suffering from bacteraemia. Information about risk factors present at the time and risk factors that served as the source of bacteraemia were noted. Total 4058 blood cultures were processed and 669(16.5%) were positive. Of them, 194(29%) cultures were found to be positive for staphylococci. Out of these 194 blood cultures, coagulase-negative staphylococci were isolated from 117(60%), and 77(40%) were positive for S. aureus. Out of these 77 samples, 26(34%) were found to be methicillin-sensitive staphylococcus aureus and 51(66%) were methicillin-resistant staphylococcus aureus. The overall frequency of methicillin-resistant staphylococcus aureus was 1.25%; 7.62% out of positive blood culture; 26.28% out of total staphylococci; and 66% out of total S. aureus. As for the source of infection, central venous pressure line 11(21.6%), post-influenza pneumonia 9(17.6%), peripheral intravenous line 8(15.7%) and dialysis line 7(13.7%) were major reasons. Taking care of aseptic measures while insertion, frequent change and early removal of the central venous and dialysis lines is of critical significance.

The warmer the weather, the more gram-negative bacteria - impact of temperature on clinical isolates in intensive care units.

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Schwab, Frank; Gastmeier, Petra; Meyer, Elisabeth

2014-01-01

We investigated the relationship between average monthly temperature and the most common clinical pathogens causing infections in intensive care patients. A prospective unit-based study in 73 German intensive care units located in 41 different hospitals and 31 different cities with total 188,949 pathogen isolates (102,377 Gram-positives and 86,572 Gram-negatives) from 2001 to 2012. We estimated the relationship between the number of clinical pathogens per month and the average temperature in the month of isolation and in the month prior to isolation while adjusting for confounders and long-term trends using time series analysis. Adjusted incidence rate ratios for temperature parameters were estimated based on generalized estimating equation models which account for clustering effects. The incidence density of Gram-negative pathogens was 15% (IRR 1.15, 95%CI 1.10-1.21) higher at temperatures ≥ 20°C than at temperatures below 5°C. E. cloacae occurred 43% (IRR=1.43; 95%CI 1.31-1.56) more frequently at high temperatures, A. baumannii 37% (IRR=1.37; 95%CI 1.11-1.69), S. maltophilia 32% (IRR=1.32; 95%CI 1.12-1.57), K. pneumoniae 26% (IRR=1.26; 95%CI 1.13-1.39), Citrobacter spp. 19% (IRR=1.19; 95%CI 0.99-1.44) and coagulase-negative staphylococci 13% (IRR=1.13; 95%CI 1.04-1.22). By contrast, S. pneumoniae 35% (IRR=0.65; 95%CI 0.50-0.84) less frequently isolated at high temperatures. For each 5°C increase, we observed a 3% (IRR=1.03; 95%CI 1.02-1.04) increase of Gram-negative pathogens. This increase was highest for A. baumannii with 8% (IRR=1.08; 95%CI 1.05-1.12) followed by K. pneumoniae, Citrobacter spp. and E. cloacae with 7%. Clinical pathogens vary by incidence density with temperature. Significant higher incidence densities of Gram-negative pathogens were observed during summer whereas S. pneumoniae peaked in winter. There is increasing evidence that different seasonality due to physiologic changes underlies host susceptibility to different bacterial pathogens

Eficácia in vitro de desinfetantes comerciais utilizados no pré e pós-dipping frente a Staphylococcus spp. isolados em rebanhos leiteiros In vitro efficacy of commercial disinfectants used in pre-and post-dipping against Staphylococcus spp. isolated from dairy cattle

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Ayodhya C. Ramalho

2012-12-01

Wasteland and Forest Zone of Alagoas, Brazil. We used iodine (0.57%, chlorhexidine (2.0%, chlorine (2.5% and quaternary ammonium compound (4.0% at concentrations indicated, conventionally used as commercial disinfectants before and after dipping. We analyzed a total of 97 isolates of Staphylococcus spp. identified as S. aureus (16, coagulase positive Staphylococcus (7 and coagulase-negative Staphylococcus (74. The disinfectants were evaluated at three different times (15", 30" and 60". We found that 56.3% of Staphylococcus aureus was sensitive to iodine, 68.8% to chlorine, 87.5% to chlorhexidine, and 37.5% to the compound of ammonia, in time 60". As for coagulase positive staphylococci (CPS, 100% of the isolates was resistant to chlorhexidine, 85.7% to the ammonia compound, 57.1% to chlorine, and 42.9% iodine, in time 60". Regarding coagulase negative staphylococci (CNS, 91.9% was sensitive to chlorhexidine, 70.3% to chlorine, 66.2% to iodine, and 24.3% the ammonium compound, at time 60". It is concluded from this study that the greatest disinfectant activity in vitro was with chlorhexidine and chlorine for S. aureus, with iodine and chlorine for SCP, and with chloride and chlorhexidine for SCN. Due to variations in the sensitivity and resistance profile found, it is necessary for regular assessments of the effectiveness of disinfectants used on the farms, to observe the effectiveness of the product and thus ensure the control of mastitis in the herd.

DISTRIBUTION OF COAGULASE-NEGATIVE STAPHYLOCOCCI SPECIES ON TEAT SKIN AND IN MILK SAMPLES FROM DAIRY COWS IN AUTOMATIC MILKING SYSTEMS

DEFF Research Database (Denmark)

Mahmmod, Yasser Saadeldien Ibrahim; Svennesen, Line; Pedersen, Karl

) to identify the predisposing cow level risk factors for specific CNS IMI and teat colonization.In each herd, 30- 40 cows with somatic cell counts > 200,000 cells/ml in the previous milk recording are randomly selected and teat skin swabs and aseptic quarter foremilk samples are taken. Teat skin swabs...... are collected using a modified wet-dry method. First a wet swab immersed in ¼ Ringer’s solution followed by a dry swab are rotated 360° around the teat canal orifice and both swab tips transferred into one tube with 2 ml of ¼ Ringer’s solution. Samples are transported on ice for culturing in the laboratory...

Economic values and expected effect of selection index for pathogen-specific mastitis under Danish conditions

DEFF Research Database (Denmark)

Sørensen, Lars Peter; Mark, Thomas; Sørensen, M.K.

2010-01-01

The objectives of this study were 1) to estimate costs related to 5 different pathogen-specific mastitis traits (susceptibility to different pathogens causing mastitis in dairy cattle) and unspecific mastitis, and 2) to compare selection differentials for an udder health index consisting of 5...... different pathogen-specific mastitis traits and lactation average somatic cell count from 5 to 170 d after first calving (LASCC170) with another index consisting of 1 unspecific mastitis trait and LASCC170. Economic values were estimated for mastitis caused by Staphylococcus aureus, Streptococcus...... dysgalactiae, Escherichia coli, coagulase-negative staphylococci, and Streptococcus uberis using a stochastic simulation model (SimHerd IV). Mastitis incidences for SimHerd IV were from incidences of mastitis treatments in primiparous Danish Holstein cows calving in 2007. Estimated costs ranged from 149 euro...

Shortened Time to Identify Staphylococcus Species from Blood Cultures and Methicillin Resistance Testing Using CHROMAgar

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Shingo Chihara

2009-01-01

Full Text Available The ability to rapidly differentiate coagulase-negative staphylococcus (CoNS from Staphylococcus aureus and to determine methicillin resistance is important as it affects the decision to treat empiric antibiotic selection. The objective of this study was to evaluate CHROMagar S. aureus and CHROMagar MRSA (Becton Dickinson for rapid identification of Staphylococcus spp. directly from blood cultures. Consecutive blood culture bottles (BacT Alert 3D SA and SN, bioMérieux growing gram-positive cocci in clusters were evaluated. An aliquot was plated onto CHROMagar MRSA (C-MRSA and CHROMagar S. aureus (C-SA plates, which were read at 12 to 16 hours. C-SA correctly identified 147/147 S. aureus (100% sensitivity; 2 CoNS were misidentified as S. aureus (98% specificity. C-MRSA correctly identified 74/77 MRSA (96% sensitivity. None of the MSSA isolates grew on C-MRSA (100% specificity. In conclusion, CHROMagar is a rapid and sensitive method to distinguish MRSA, MSSA, and coagulase-negative Staphylococcus and may decrease time of reporting positive results.

Antimicrobial susceptibility of Staphylococcus saprophyticus and urethral staphylococci.

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Marrie, T J; Kwan, C

1982-01-01

The activity of eight antimicrobial agents was determined against 115 isolates of Staphylococcus saprophyticus. All were susceptible to ampicillin, cephalexin, and trimethoprim-sulfamethoxazole and resistant to nalidixic acid and novobiocin. A bimodal pattern of susceptibility to erythromycin was observed: 80% were inhibited by 0.25 microgram/ml, whereas 13% required greater than or equal to 128 micrograms/ml. The following urethral staphylococci were susceptible to ampicillin, cephalexin, and nitrofurantoin but resistant to nalidixic acid: S. epidermidis, S. hominis, S. haemolyticus, S. warneri, S. simulans, and S. cohnii. PMID:6982679

Competitive time- and density-dependent adhesion of staphylococci and osteoblasts on crosslinked poly(ethylene glycol)-based polymer coatings in co-culture flow chambers.

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Saldarriaga Fernández, Isabel C; Busscher, Henk J; Metzger, Steve W; Grainger, David W; van der Mei, Henny C

2011-02-01

Biomaterial-associated infections (BAI) remain a serious clinical complication, often arising from an inability of host tissue-implant integration to out-compete bacterial adhesion and growth. A commercial polymer coating based on polyethylene glycol (PEG), available in both chemically inert and NHS-activated forms (OptiChem(®)), was compared for simultaneous growth of staphylococci and osteoblasts. In the absence of staphylococci, osteoblasts adhered and proliferated well on glass controls and on the NHS-reactive PEG-based coating over 48 h, but not on the inert PEG coating. Staphylococcal growth was low on both PEG-based coatings. When staphylococci were pre-adhered on surfaces for 1.5 h to mimic peri-operative contamination, osteoblast growth and spreading was reduced on glass but virtually absent on both reactive and inert PEG-based coatings. Thus although NHS-reactive, PEG-based coatings stimulated tissue-cell interactions in the absence of contaminating staphylococci, the presence of adhering staphylococci eliminated osteoblast adhesion advantages on the PEG surface. This study demonstrates the importance of using bacterial and cellular co-cultures compared to monocultures when assessing functionalized biomaterials coatings for infectious potential. Copyright © 2010 Elsevier Ltd. All rights reserved.

Incidence of clinical mastitis and distribution of pathogens on large Chinese dairy farms.

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Gao, Jian; Barkema, Herman W; Zhang, Limei; Liu, Gang; Deng, Zhaoju; Cai, Lingjie; Shan, Ruixue; Zhang, Shiyao; Zou, Jiaqi; Kastelic, John P; Han, Bo

2017-06-01

Knowledge of the incidence of clinical mastitis (CM) and the distribution of pathogens involved is essential for development of prevention and control programs as well as treatment protocols. No country-wide study on the incidence of CM and the distribution of pathogens involved has been conducted in China. Core objectives of this study were, therefore, to determine the cumulative incidence of CM and the distribution of pathogens causing CM on large Chinese (>500 cows) dairy farms. In addition, associations between the distribution of CM pathogens and bedding materials and seasonal factors were also investigated. Bacterial culture was done on a total of 3,288 CM quarter milk samples from 161 dairy herds (located in 21 provinces) between March 2014 and September 2016. Additional data, including geographical region of herds, herd size, bedding types, and number of CM cases during the last month, were also recorded. Mean cumulative incidence of CM was 3.3 cases per 100 cows per month (range = 1.7 to 8.1). The most frequently isolated pathogens were Escherichia coli (14.4%), Klebsiella spp. (13.0%), coagulase-negative staphylococci (11.3%), Streptococcus dysgalactiae (10.5%), and Staphylococcus aureus (10.2%). Streptococcus agalactiae was isolated from 2.8% of CM samples, whereas Streptococcus uberis were isolated from 2.1% of samples, and 15.8% of 3,288 samples were culture-negative. Coagulase-negative staphylococci, E. coli, and other Enterobacter spp. were more frequently isolated in the northwest than the northeast or south of China. Streptococcus dysgalactiae, other streptococci, and Strep. agalactiae were more frequently isolated in winter (October-March), whereas E. coli and Klebsiella spp. were mostly isolated in summer (April-September). Streptococcus dysgalactiae was more often isolated from CM cases of herds using sand bedding, whereas Klebsiella spp. and other streptococci were more common in herds using organic bedding. The incidence of CM and distribution

Prescribing prophylactic antibiotics to users of therapeutic contact lenses.

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Colomé-Campos, J; Quevedo-Junyent, L; Godoy-Barreda, N; Martínez-Salcedo, I; Romero-Aroca, P

2013-03-01

To describe the benefits and optimum use of prophylactic antibiotics in users of therapeutic contact lenses (TCL). A microbiological study was carried out on samples from 33 patients who continuously wore TCL. The resistance to antibiotics of bacteria isolated in our health region was also reviewed. An assessment was also made on whether there were microorganisms of a higher pathogenic potential in TCL than conventional contact lenses, as reported in the literature. No bacteria were isolated from 17 (52%) of the 33 lenses studied. From the 16 (48%) remaining lenses, coagulase negative Staphylococci were isolated from 10 (62%), Propionibacterium acnes from 4 (25%), and Corynebacterium from 2 (13%). The high number of negative cultures and the presence of saprophytic bacteria indicate that prophylactic antibiotic treatment is not precise. The most frequent pathogenic bacteria found in contact lenses are strongly resistant to the current commercially available antibiotics. Copyright © 2012 Sociedad Española de Oftalmología. Published by Elsevier Espana. All rights reserved.

Trends in risk factors and etiology of 606 cases of infective endocarditis over 23 years (1984-2006) in slovakia.

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Hricak, V; Liska, B; Kovackova, J; Mikusova, J; Fischer, V; Kovacik, J; Karvaj, M; Jurco, R; Ondrusova, A; Kalavsky, E; Marks, P; Beno, P; Krcmery, V

2007-04-01

The aim of this study was to assess trends in risk factors, etiology, outcome and treatment strategies for endocarditis over 23 years in Slovakia. A prospective survey of 606 cases of infective endocarditis (IE) was conducted from 1984-2006. Rheumatic fever as well as previous dental surgery showed decreasing trends within the last 23 years. Also embolic complications of IE declined along with increasing rates of surgically treated patients. No significant changes in etiology were detected apart from the fact that culture-negative endocarditis increased from 10.7% to 55.4% between 1998-2001. Surgically treated patients increased from 22.7% (1984-1990) to 50.1% (2002-2006) and mortality dramatically decreased from 26.7% (1984-1990) to 5.3% (2002-2006). Staphylococcus aureus and coagulase-negative staphylococci were the leading causes (22.4% - 48%) followed by viridans streptococci (12.2%-18.2%) were a relatively stable trend over 23 years of IE in Slovakia.

Characterization of wound infections among patients injured during the 2011 Libyan conflict.

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Dau, A A; Tloba, S; Daw, M A

2013-04-01

Few studies have analysed the bacterial pathogenesis of infections associated with war-wound in the Eastern Mediterranean region. We analysed surgical wound infections of 1200 patients injured during the Libyan conflict in 2011 and admitted to the emergency services at Tripoli medical centre. Culture swabs or surgical wound debridement samples were collected and cultures were identified and tested for antimicrobial resistance. Of the 1200 patients studied, 498 (42%) were infected with at least 1 pathogen and 57 with >2 pathogens. The most common species were Acinetobacter spp. (isolated from 144 patients), coagulase-negative staphylococci (122), Escherichia coli (107), Pseudomnonas aeruginosa (92) and Klebsiella spp. (86). A high level of resistance to the antibiotics tested was found, especially among Acinetobacter spp. Multi-drug-resistant Gram-negative bacilli were an important complicating factor in wound infections associated with war injuries among injured patients in Libya. Effective policies are needed to control and treat such infections particularly in trauma and emergency services.

PREVALENCE AND ANTIBIOTIC RESISTANCE OF STAPHYLOCOCCI ISOLATED FROM KOLEA HOSPITAL (ALGERIA

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M. N. Boukhatem

2015-03-01

Full Text Available The resurgence of multiple antibiotic resistances is a major public health problem, often causing therapeutic impasses. Our study was conducted at the Bacteriology Laboratory of Kolea (Tipaza, Algeria Hospital. The aim of this study was to determine the prevalence of staphylococci in clinical purulent, sepsis and urinary samples, and to test the sensitivity of the selected strains against a various antibiotic (ATB discs. The identification of Staphylococcus strains was performed by using classic biochemistry tests. Susceptibility against ATB was determined by the agar disk diffusion method. Among 1403 clinical samples obtained, only 61 was related to staphylococci infections (4.34%. Staphylococcus strains were found mainly in the purulent samples (60.65%. S.aureus was found to be the mainly isolated strains with a rate of 61.53% while the S. epidermidis strain was found predominantly in hospitalized patients (68.57%. The frequency of the overall resistance of S.aureus against penicillin G (80.6% and gentamicin (61.53% remains high. The multi-resistant Staphylococcus has become extremely widespread, hence the need for the accomplishment of a strategy to prevent the spread of this resistance.

PREVALENCE AND ANTIBIOTIC RESISTANCE OF STAPHYLOCOCCI ISOLATED FROM KOLEA HOSPITAL (ALGERIA

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M. N. Boukhatem

2015-05-01

Full Text Available The resurgence of multiple antibiotic resistances is a major public health problem, often causing therapeutic impasses. Our study was conducted at the Bacteriology Laboratory of Kolea (Tipaza, Algeria Hospital. The aim of this study was to determine the prevalence of staphylococci in clinical purulent, sepsis and urinary samples, and to test the sensitivity of the selected strains against a various antibiotic (ATB discs. The identification of Staphylococcus strains was performed by using classic biochemistry tests. Susceptibility against ATB was determined by the agar disk diffusion method. Among 1403 clinical samples obtained, only 61 was related to staphylococci infections (4.34%. Staphylococcus strains were found mainly in the purulent samples (60.65%. S.aureus was found to be the mainly isolated strains with a rate of 61.53% while the S. epidermidis strain was found predominantly in hospitalized patients (68.57%. The frequency of the overall resistance of S.aureus against penicillin G (80.6% and gentamicin (61.53% remains high. The multi-resistant Staphylococcus has become extremely widespread, hence the need for the accomplishment of a strategy to prevent the spread of this resistance.

Competing for Iron: Duplication and Amplification of the isd Locus in Staphylococcus lugdunensis HKU09-01 Provides a Competitive Advantage to Overcome Nutritional Limitation

Science.gov (United States)

Heilbronner, Simon; Brozyna, Jeremy R.; Heinrichs, David E.; Skaar, Eric P.; Peschel, Andreas; Foster, Timothy J.

2016-01-01

Staphylococcus lugdunensis is a coagulase negative bacterial pathogen that is particularly associated with severe cases of infectious endocarditis. Unique amongst the coagulase-negative staphylococci, S. lugdunensis harbors an iron regulated surface determinant locus (isd). This locus facilitates the acquisition of heme as a source of nutrient iron during infection and allows iron limitation caused by “nutritional immunity” to be overcome. The isd locus is duplicated in S. lugdunensis HKU09-01 and we show here that the duplication is intrinsically unstable and undergoes accordion-like amplification and segregation leading to extensive isd copy number variation. Amplification of the locus increased the level of expression of Isd proteins and improved binding of hemoglobin to the cell surface of S. lugdunensis. Furthermore, Isd overexpression provided an advantage when strains were competing for a limited amount of hemoglobin as the sole source of iron. Gene duplications and amplifications (GDA) are events of fundamental importance for bacterial evolution and are frequently associated with antibiotic resistance in many species. As such, GDAs are regarded as evolutionary adaptions to novel selective pressures in hostile environments pointing towards a special importance of isd for S. lugdunensis. For the first time we show an example of a GDA that involves a virulence factor of a Gram-positive pathogen and link the GDA directly to a competitive advantage when the bacteria were struggling with selective pressures mimicking “nutritional immunity”. PMID:27575058

Occurrence of Clinical and Sub-Clinical Mastitis in Dairy Herds in the West Littoral Region in Uruguay

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Rivero R

2002-12-01

Full Text Available Twenty-nine dairy farms were selected to determine the incidence of clinical mastitis, prevalence of sub-clinical mastitis and bacterial aetiology in the West Littoral Region of Uruguay. In samples taken by the owner and frozen at -20°C during a week the incidence rate of clinical mastitis was determined as 1.2 cases per 100 cow-months at risk. Staphylococcus aureus was the most common isolated pathogen in 37.5% of 40 milk samples from clinical cases obtained in 1 month. No bacteria grew in the 32.5% of the total samples. A sub-sample including 1077 dairy cows from randomly selected farms was used to determine the prevalence of sub-clinical mastitis. These samples were taken on one visit to each farm. The prevalence was 52.4% on a cow basis and 26.7% on an udder quarter basis. In 55.1% of the quarters of the selected animals with more than 300 000 cells/ml there was no growth. The isolated pathogens from sub-clinical cases and their relative frequencies were: Staphylococcus aureus 62.8%, Streptococcus agalactiae 11.3%, Enterococcus sp. 8%, coagulase-negative staphylococci 7.4%, Streptococus uberis 6.4%, Streptococcus dysgalactiae 1.8%, Escherichia coli 1.5% and Staphylococcus hyicus coagulase-positive 0.6%.

CARACTERIZAÇÃO DO STAPHYLOCOCCUS COAGULASE NEGATIVO ISOLADOS DE QUARTOS MAMÁRIOS DE VACAS COM MASTITE SUBCLÍNICA

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Marlice Teixeira Ribeiro

1994-01-01

Full Text Available RESUMO O presente trabalho foi desenvolvido na Zona da Mata - MG, durante três meses. De quatro rebanhos utilizados, trabalhou-se com 16 animais mestiços e 19 holandeses. O objetivo foi caracterizar Staphylococcus coagulase negativos, isolados de quartos mamários de vacas, que inicialmente reagiam à prova do "Califórnia Mastitis Test" (CMT, em quatro testes consecutivos, a intervalo de uma semana. A caracterização das 116 amostras encontradas, correspondentes a Staphylococcus coagulase negativo, foram: S. epidermidis (71,55%, S. hyicus subsp. chromogenes (6,03%, S. simulans (6,03%, S. warneri (4,31%, S. hominis (3,45%, S. cohnii (3,45%, S. sciuri (3,45% e S. haemolyticus (1,73%.

Comparison of three phenotypic techniques for detection of methicillin resistance in Staphylococcus spp. reveals a species-dependent performance.

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John, Michael A; Burden, Julia; Stuart, J Ian; Reyes, Romina C; Lannigan, Robert; Milburn, Sue; Diagre, Deb; Wilson, Bev; Hussain, Zafar

2009-03-01

To evaluate the usefulness of the cefoxitin screen in Vitek 2 Gram-positive panels for recognizing methicillin-resistant strains of staphylococci. Seven hundred and ninety-nine non-duplicate isolates of Staphylococcus aureus and coagulase-negative strains were included in the study. Methicillin resistance was measured using PCR for the mecA gene, the CLSI cefoxitin disc diffusion method, the Vitek 2 cefoxitin screen and the Vitek 2 oxacillin susceptibility test. Compared with the molecular detection of methicillin resistance the overall sensitivities and specificities of the phenotypic tests for cefoxitin disc diffusion were 94.9% and 97.0%, for Vitek 2 cefoxitin screen were 94.6% and 93.5% and for Vitek 2 oxacillin susceptibility test were 93.8% and 77.9%. The cephamycin tests (cefoxitin disc diffusion and Vitek 2 screen) were not able to identify mecA-positive strains of Staphylococcus simulans. In addition, the performance of the Vitek 2 system was poor against Staphylococcus cohnii subspecies, Staphylococcus hominis hominis and Staphylococcus saprophyticus. Overall, the performance of the Vitek 2 system for differentiating mecA-positive staphylococci was comparable to PCR and the CLSI disc diffusion method; however, performance was species-dependent. Thus, before accepting the results produced by Vitek 2, species identification may be required.

The stethoscope in the Emergency Department: a vector of infection?

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Núñez, S.; Moreno, A.; Green, K.; Villar, J.

2000-01-01

The purposes of this study were to determine whether microorganisms can be isolated from the membranes of stethoscopes used by clinicians and nurses, and to analyse whether or not the degree of bacterial colonization could be reduced with different cleaning methods. We designed a transversal before-after study in which 122 stethoscopes were examined. Coagulase negative staphylococci (which are also potentially pathogenic microorganisms) were isolated together with 13 other potentially pathogenic microorganisms, including S. aureus, Acinetobacter sp. and Enterobacter agglomerans. The most effective antiseptic was propyl alcohol. Analysis of the cleaning habits of the Emergency Department (ED) staff, showed that 45% cleaned the stethoscope annually or never. The isolation of potentially pathogenic microorganisms suggests that the stethoscope must be considered as a potential vector of infection not only in the ED but also in other hospital wards and out-patient clinics. PMID:10813148

Degradation of Uniquely Glycosylated Secretory Immunoglobulin A in Tears From Patients With Pseudomonas aeruginosa Keratitis

DEFF Research Database (Denmark)

Lomholt, Jeanet Andersen; Kilian, Mogens

2008-01-01

PURPOSE. To investigate the integrity of secretory IgA (S-IgA) in tear fluid during bacterial keratitis and to evaluate the significance of specific Pseudomonas aeruginosa extracellular proteases in the observed degradation of S-IgA. METHODS. The integrity of component chains of S-IgA in tear fluid...... from patients with keratitis caused by P. aeruginosa, Streptococcus group G, Moraxella catarrhalis, Staphylococcus aureus, coagulase-negative staphylococci, and the IgA1 protease-producing Streptococcus pneumoniae were compared with S-IgA in tear fluid, colostrum, and saliva from healthy individuals......, and with tear S-IgA incubated with clinical isolates and genetically engineered P. aeruginosa strains with different protease profiles. Degradation of S-IgA and the significance of its glycosylation were analyzed in Western blots developed with antibodies against individual chains of S-IgA. RESULTS. Secretory...

Changes of the Quinolones Resistance to Gram-positive Cocci Isolated during the Past 8 Years in the First Bethune Hospital

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Xu, Jiancheng; Chen, Qihui; Yao, Hanxin; Zhou, Qi

This study was to investigate the quinolones resistance to gram-positive cocci isolated in the First Bethune Hospital during the past 8 years. Disk diffusion test was used to study the antimicrobial resistance. The data were analyzed by WHONET 5 software according to Clinical and Laboratory Standards Institute (CLSI). The rates of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase-negative Staphylococci (MRCNS) were 50.8%∼83.3% and 79.4%∼81.5%during the past 8 years, respectively. In recent 8 years, the quinolones resistance to gram-positive cocci had increased. Monitoring of the quinolones resistance to gram-positive cocci should be strengthened. The change of the antimicrobial resistance should be investigated in order to guide rational drug usage in the clinic and prevent bacterial strain of drug resistance from being transmitted.

Activity of vancomycin, linezolid, and daptomycin against staphylococci and enterococci isolated in 5 Greek hospitals during a 5-year period (2008-2012).

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Papadimitriou-Olivgeris, Matthaios; Kolonitsiou, Fevronia; Zerva, Loukia; Lebessi, Evangelia; Koutsia, Chryssa; Drougka, Eleanna; Sarrou, Styliani; Giormezis, Nikolaos; Vourli, Sofia; Doudoulakakis, Anastassios; Konsolakis, Christos; Marangos, Markos; Anastassiou, Evangelos D; Petinaki, Efthimia; Spiliopoulou, Iris

2015-12-01

The tendency of vancomycin, linezolid, and daptomycin MICs was investigated among 6920 staphylococci and enterococci during a 5-year period. Antimicrobial consumption was determined. Decrease of vancomycin MIC was detected associated with reduction in consumption. Linezolid and daptomycin remained active. An upward trend of linezolid MIC for methicillin-resistant staphylococci was observed. Copyright © 2015 Elsevier Inc. All rights reserved.

Microbiological profile and nutritional quality of raw foods for neutropenic patients under hospital care

OpenAIRE

Galati, Paula Cristina; Lataro, Renata Cristina; Souza, Vanessa Maciel; de Martinis, Elaine Cristina Pereira; Chiarello, Paula Garcia

2013-01-01

Objective This study aimed to analyze and compare the microbiological profile and vitamin C content of raw and cooked foods destined for neutropenic inpatients. Methods Three vegetables and nine fruits, raw and boiled, washed and sanitized were examined. Heat-tolerant coliforms and coagulase-positive staphylococci were counted and the presence of Salmonella spp was investigated. The vitamin C content was analyzed by a colorimetric reaction. The Statistical Package for Social Sciences (SPSS) s...

Microbiological profile and nutritional quality of raw foods for neutropenic patients under hospital care

OpenAIRE

Galati, Paula Cristina; Lataro, Renata Cristina; Souza, Vanessa Maciel; Martinis, Elaine Cristina Pereira de; Chiarello, Paula Garcia

2013-01-01

OBJECTIVE: This study aimed to analyze and compare the microbiological profile and vitamin C content of raw and cooked foods destined for neutropenic inpatients. METHODS: Three vegetables and nine fruits, raw and boiled, washed and sanitized were examined. Heat-tolerant coliforms and coagulase-positive staphylococci were counted and the presence of Salmonella spp was investigated. The vitamin C content was analyzed by a colorimetric reaction. The Statistical Package for Social Sciences (SPSS)...

Occurrence and antimicrobial sensitivity in staphylococci isolated from goat, sheep and cow’s milk

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Marcela Vyletělová

2011-01-01

Full Text Available The aim of this study was to compare the sensitivity to selected antibiotics in staphylococci isolated from goat (n = 60, sheep (n = 60 and cow’s milk (n = 120. The individual milk samples were inoculated onto Blood agar cultivated at 36 °C/24 h.The isolated species of staphylococci were identified using biochemical tests, namely STAPHYtest and identification program TNW pro 6.5. We examined the sensitivity of strains to the spectrum of antibiotics, as follows: vancomycin (VA, amoxicillin/clavulanic acid (AMC, penicillin (P, rifampicin (RD, oxacillin (OX, tetracycline (TE, erythromycin (E, chloramphenicol (C, clindamycin (DA, gentamicin (CN, ciprofloxacin (CIP, teicoplanin (TEC, cefoxitin (FOX and novobiocin (NOV. Altogether, 97 staphylococcal isolates were obtained; 70 from cow’s milk, 11 from goat’s milk and 16 from sheep’ milk. Staphylococcus aureus was the most frequent species in milk of all animal origin tested, was detected in 54 (45% cow’s milk, 10 (17% goat’s and 15 (25% sheep’ milk samples. S. lentus was identified only in goat’s and sheep’ milk whereas in cow’s milk there were representation of staphylococcal species as follows: S. haemolyticus (n = 7, S. chromogenes (n = 2, S. warneri (n = 2, S. xylosus (n = 2, S. epidermidis (n = 2 and unclassified staphylococci (n = 1. The results of S. aureus sensitivity are similar for all tested antibiotics and for all monitored milk: No resistance to vancomycin, rifampicin, chloramphenicol and teicoplanin was recorded in obtained S. aureus isolates whereas the resistance to ciprofloxacin was found out most often.

VOGES-PROSKAUER AND COAGULASE TESTS TO THE LABORATORIAL DIAGNOSTIC OF Staphylococcus aureus INCLUDED IN THE EPIDEMIOLOGY OF BOVINE MASTITIS UTILIZAÇÃO DO TESTE DE VOGES-PROSKAUER E DA COAGULASE PARA O DIAGNÓSTICO LABORATORIAL DE Staphylococcus aureus ENVOLVIDOS NA EPIDEMIOLOGIA DA MASTITE BOVINA

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Luiz Francisco Zafalon

2009-12-01

Full Text Available Diagnostic characteristics of acetoin production to the Staphylococcus aureus isolated from milk of mammary quarters of cows with mastitis, orifices of teats and mouthpieces of the liners were studied, in agreement to different coagulation grades presented by strains in the tube coagulase test with rabbit plasma and different rain levels in the environment of the herd. The production of acetoin and the coagulase test were performed after growth on blood agar base supplemented with sheep blood, Gram staining and catalase production. All strains were confirmed by molecular identification at species level by species-specific PCR. Among 329 samples identified, 167 were isolated from milk, 117 from teat orifices and 45 from mouthpieces of the liners. Among these samples, 85.0%, 71.1% and 69.2% strains originated from the milk, mouthpieces and orifices, respectively, presented whole coagulation in the coagulase test. Reduced specificities were obtained to the acetoin production to different coagulation grades on the few rains period as well as on the many rains period. Sensitivities to the acetoin production were higher on the few rains period to all sources and coagulation grades, except to strains from orifices with incomplete coagulation and strains from mouthpieces with complete coagulation. It is recommended the acetoin production test how a good diagnostic strategy to the S. aureus identification, combined with other tests how coagulase, mainly in the milk samples originated from mastitic mammary quarters and on periods with little occurrence of rains.

SOME ASPECTS OF NASAL CARRIAGE OF STAPHYLOCOCCI.

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NOBLE, W C; WILLIAMS, R E; JEVONS, M P; SHOOTER, R A

1964-01-01

The nasal carrier status of 3,736 patients was determined throughout their stay in hospital. The carrier rate on admission, which was highest in patients under 20 years of age, did not appear to vary with season.The carriage of strains resistant to penicillin increased with the patients' stay in hospital from 13.% on admission to 20.5% on discharge, and the acquisition of these strains was enhanced by the administration of antibiotics. Patients discharged from hospital carrying strains of staphylococci acquired in hospital lost them more readily than patients discharged carrying the strain which they had carried on admission, 31% of those discharged carrying strains resistant to penicillin and tetracycline being readmitted carrying these strains compared with 69% of those discharged carrying strains sensitive to these antibiotics.

The warmer the weather, the more gram-negative bacteria - impact of temperature on clinical isolates in intensive care units.

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Frank Schwab

Full Text Available BACKGROUND: We investigated the relationship between average monthly temperature and the most common clinical pathogens causing infections in intensive care patients. METHODS: A prospective unit-based study in 73 German intensive care units located in 41 different hospitals and 31 different cities with total 188,949 pathogen isolates (102,377 Gram-positives and 86,572 Gram-negatives from 2001 to 2012. We estimated the relationship between the number of clinical pathogens per month and the average temperature in the month of isolation and in the month prior to isolation while adjusting for confounders and long-term trends using time series analysis. Adjusted incidence rate ratios for temperature parameters were estimated based on generalized estimating equation models which account for clustering effects. RESULTS: The incidence density of Gram-negative pathogens was 15% (IRR 1.15, 95%CI 1.10-1.21 higher at temperatures ≥ 20°C than at temperatures below 5°C. E. cloacae occurred 43% (IRR=1.43; 95%CI 1.31-1.56 more frequently at high temperatures, A. baumannii 37% (IRR=1.37; 95%CI 1.11-1.69, S. maltophilia 32% (IRR=1.32; 95%CI 1.12-1.57, K. pneumoniae 26% (IRR=1.26; 95%CI 1.13-1.39, Citrobacter spp. 19% (IRR=1.19; 95%CI 0.99-1.44 and coagulase-negative staphylococci 13% (IRR=1.13; 95%CI 1.04-1.22. By contrast, S. pneumoniae 35% (IRR=0.65; 95%CI 0.50-0.84 less frequently isolated at high temperatures. For each 5°C increase, we observed a 3% (IRR=1.03; 95%CI 1.02-1.04 increase of Gram-negative pathogens. This increase was highest for A. baumannii with 8% (IRR=1.08; 95%CI 1.05-1.12 followed by K. pneumoniae, Citrobacter spp. and E. cloacae with 7%. CONCLUSION: Clinical pathogens vary by incidence density with temperature. Significant higher incidence densities of Gram-negative pathogens were observed during summer whereas S. pneumoniae peaked in winter. There is increasing evidence that different seasonality due to physiologic changes underlies

Celularidade do leite e Unidades Formadoras de Colônias nas mastites causadas por Staphylococcus coagulase positiva e coagulase negativa

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Helio Langoni

2015-06-01

Full Text Available Resumo: A mastite é a principal afecção do gado destinado à produção leiteira, que impacta significativamente a cadeia produtiva do leite, com reflexos ainda para a saúde pública. Estudou-se aspectos relacionados à etiologia, celularidade e de contagem bacteriana em 10 propriedades leiteiras, localizadas no Estado de São Paulo. Foram examinadas 1148 vacas em lactação, totalizando 4584 glândulas mamárias. Foram considerados os casos, em que houve isolamento de estafilococos coagulase positiva (SCP e estafilococos coagulase negativa (SCN. Os resultados revelaram microbiota com vários patógenos e diferentes espécies de SCN (128 casos e SCP (45, Staphylococcus aureus(90, Streptococcus agalactiae(70, Streptococcus dysgalactiae (69, Streptococcus uberis(29, Corynebacteriumspp. (230, Klebsiella pneumoniae(28, Klebsiella oxytoca(2, Escherichia coli(15, Enterobactersp. (3. Os resultados de contagem de células somáticas (CCS relacionados aos SCP e SCN não mostraram diferenças entre as propriedades avaliadas, entretanto com diferenças significantes ao se avaliar a CCS entre os dois grupos de estafilococos, como pode ser evidenciado ao comparar SCN Discreto e SCP exuberante (P<0,01, SCP Discreto e SCP exuberante (P<0,001 e SCN moderado e SCP exuberante (P<0,01. A avaliação da CCS relacionada à intensidade da infecção, considerando-se como crescimento discreto o isolamento de até nove colônias, moderado de dez a 29 colônias e exuberante, com 30 ou mais colônias, revelou para ambos os grupos de estafilococos que quanto maior o número de unidades formadoras de colônias (UFC, a CCS é mais elevada, sendo sempre maior nos casos de SCP. Conclui-se que quando há maior número de UFC, há concomitantemente maior CCS/mL de leite, no caso dos SCP e SCN, o que mostra relação direta da intensidade do processo infeccioso com a resposta da celularidade do leite, bem como pela relevância desses na etiologia das mastites e dos aspectos

Bacteriological etiology and treatment of mastitis in Finnish dairy herds.

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Vakkamäki, Johanna; Taponen, Suvi; Heikkilä, Anna-Maija; Pyörälä, Satu

2017-05-25

The Finnish dairy herd recording system maintains production and health records of cows and herds. Veterinarians and farmers register veterinary treatments in the system. Milk samples for microbiological analysis are routinely taken from mastitic cows. The laboratory of the largest dairy company in Finland, Valio Ltd., analyzes most samples using real-time PCR. This study addressed pathogen-specific microbiological data and treatment and culling records, in combination with cow and herd characteristics, from the Finnish dairy herd recording system during 2010-2012. The data derived from 240,067 quarter milk samples from 93,529 dairy cows with mastitis; 238,235 cows from the same herds served as the control group. No target pathogen DNA was detected in 12% of the samples. In 49% of the positive samples, only one target species and in 19%, two species with one dominant species were present. The most common species in the samples with a single species only were coagulase-negative staphylococci (CNS) (43%), followed by Staphylococcus aureus (21%), Streptococcus uberis (9%), Streptococcus dysgalactiae (8%), Corynebacterium bovis (7%), and Escherichia coli (5%). On average, 36% of the study cows and 6% of the control cows had recorded mastitis treatments during lactation. The corresponding proportions were 16 and 6% at drying-off. For more than 75% of the treatments during lactation, diagnosis was acute clinical mastitis. In the milk samples from cows with a recorded mastitis treatment during lactation, CNS and S. aureus were most common, followed by streptococci. Altogether, 48% of the cows were culled during the study. Mastitis was reported as the most common reason to cull; 49% of study cows and 18% of control cows were culled because of mastitis. Culling was most likely if S. aureus was detected in the milk sample submitted during the culling year. The PCR test has proven to be an applicable method also for large-scale use in bacterial diagnostics. In the present

Prevalence and bacterial etiology of subclinical mastitis in goats reared in organized farms

Science.gov (United States)

Mishra, A. K.; Sharma, Nitika; Singh, D. D.; Gururaj, K.; Abhishek; Kumar, Vijay; Sharma, D. K.

2018-01-01

Aim: Assessment of the status of subclinical mastitis (SCM) in Jamunapari and Barbari goats in Indian organized farms, the involvement of bacterial pathogens and their sensitivity to antibiotics. Materials and Methods: A total of 181 composite milk samples were aseptically collected from the apparently healthy Barbari (n=95) and Jamunapari (n=86) goats. The California mastitis test (CMT) and somatic cell count (SCC) were used to diagnose SCM. The milk samples with CMT scores of 0 and +1 were considered as negative, while the samples with the score of +2 or +3 were taken as positive, and further, the positive samples were used for the bacteriological examination. An antibiotic sensitivity test was performed by disk diffusion method using seven commercially available antibiotic discs. Results: All the samples having CMT score of +2 or +3 demonstrated SCC more than 1 million. Overall, the prevalence of SCM in the goats was assessed as 19.89% (36/181). The prevalence of SCM in Barbari and Jamunapari goats was found as 24.21% (23/95) and 15.12% (13/86), respectively. Out of 11 isolates of Staphylococci, 9 isolates were identified as coagulase-negative Staphylococci (CNS), whereas 2 isolates were found as Staphylococcus aureus. The identified bacterial isolates (n=30) did not show antibiotic resistance. Conclusion: The current investigation showed the considerable prevalence of SCM among Jamunapari and Barbari goats which may have a negative impact on quantity and quality of the milk. CNS was found as the most prevalent cause of SCM in the goats. Negligible antibiotic resistance was found among the identified udder pathogens. PMID:29479152

Evaluation of a real-time PCR assay for detection and quantification of bacterial DNA directly in blood of preterm neonates with suspected late-onset sepsis.

Science.gov (United States)

van den Brand, Marre; van den Dungen, Frank A M; Bos, Martine P; van Weissenbruch, Mirjam M; van Furth, A Marceline; de Lange, Annemieke; Rubenjan, Anna; Peters, Remco P H; Savelkoul, Paul H M

2018-04-22

Rapid and accurate diagnosis of neonatal sepsis is highly warranted because of high associated morbidity and mortality. The aim of this study was to evaluate the performance of a novel multiplex PCR assay for diagnosis of late-onset sepsis and to investigate the value of bacterial DNA load (BDL) determination as a measure of infection severity. This cross-sectional study was conducted in a neonatal intensive care unit. Preterm and/or very low birth weight infants suspected for late-onset sepsis were included. Upon suspicion of sepsis, a whole blood sample was drawn for multiplex PCR to detect the eight most common bacteria causing neonatal sepsis, as well as for blood culture. BDL was determined in episodes with a positive multiplex PCR. In total, 91 episodes of suspected sepsis were investigated, and PCR was positive in 53 (58%) and blood culture in 60 (66%) episodes, yielding no significant difference in detection rate (p = 0.17). Multiplex PCR showed a sensitivity of 77%, specificity of 81%, positive predictive value of 87%, and negative predictive value of 68% compared with blood culture. Episodes with discordant results of PCR and blood culture included mainly detection of coagulase-negative staphylococci (CoNS). C-reactive protein (CRP) level and immature to total neutrophil (I/T) ratio were lower in these episodes, indicating less severe disease or even contamination. Median BDL was high (4.1 log 10 cfu Eq/ml) with a wide range, and was it higher in episodes with a positive blood culture than in those with a negative blood culture (4.5 versus 2.5 log 10 cfu Eq/ml; p PCR provides a powerful assay to enhance rapid identification of the causative pathogen in late-onset sepsis. BDL measurement may be a useful indicator of severity of infection.

Nosocomial Bloodstream Infections in Brazilian Pediatric Patients: Microbiology, Epidemiology, and Clinical Features

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Pereira, Carlos Alberto Pires; Marra, Alexandre R.; Camargo, Luis Fernando Aranha; Pignatari, Antônio Carlos Campos; Sukiennik, Teresa; Behar, Paulo Renato Petersen; Medeiros, Eduardo Alexandrino Servolo; Ribeiro, Julival; Girão, Evelyne; Correa, Luci; Guerra, Carla; Carneiro, Irna; Brites, Carlos; Reis, Marise; de Souza, Marta Antunes; Tranchesi, Regina; Barata, Cristina U.; Edmond, Michael B.

2013-01-01

Background Nosocomial bloodstream infections (nBSIs) are an important cause of morbidity and mortality and are the most frequent type of nosocomial infection in pediatric patients. Methods We identified the predominant pathogens and antimicrobial susceptibilities of nosocomial bloodstream isolates in pediatric patients (≤16 years of age) in the Brazilian Prospective Surveillance for nBSIs at 16 hospitals from 12 June 2007 to 31 March 2010 (Br SCOPE project). Results In our study a total of 2,563 cases of nBSI were reported by hospitals participating in the Br SCOPE project. Among these, 342 clinically significant episodes of BSI were identified in pediatric patients (≤16 years of age). Ninety-six percent of BSIs were monomicrobial. Gram-negative organisms caused 49.0% of these BSIs, Gram-positive organisms caused 42.6%, and fungi caused 8.4%. The most common pathogens were Coagulase-negative staphylococci (CoNS) (21.3%), Klebsiella spp. (15.7%), Staphylococcus aureus (10.6%), and Acinetobacter spp. (9.2%). The crude mortality was 21.6% (74 of 342). Forty-five percent of nBSIs occurred in a pediatric or neonatal intensive-care unit (ICU). The most frequent underlying conditions were malignancy, in 95 patients (27.8%). Among the potential factors predisposing patients to BSI, central venous catheters were the most frequent (66.4%). Methicillin resistance was detected in 37 S. aureus isolates (27.1%). Of the Klebsiella spp. isolates, 43.2% were resistant to ceftriaxone. Of the Acinetobacter spp. and Pseudomonas aeruginosa isolates, 42.9% and 21.4%, respectively, were resistant to imipenem. Conclusions In our multicenter study, we found a high mortality and a large proportion of gram-negative bacilli with elevated levels of resistance in pediatric patients. PMID:23861860

Interrelationships Within the Bacterial Flora of the Female Genital Tract

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Henry J. Carson

1997-01-01

Full Text Available Analysis of 240 consecutive vaginal swabs using the compatibility profile technique revealed that only 2 bacteria have the ability to be a sole isolate and as such a candidate to be a major aerobic regulator of the bacterial flora of the female genital tract (BFFGT. Compatibility profiles of Lactobacillus and Gardnerella vaginalis have shown that these organisms shared compatibility profiling for the majority of the normal bacterial constituents of the female genital tract. Dominance disruption appears to come from the addition of compatible co-isolates and presumed loss of numerical superiority. These phenomena appear to be the keys to reregulation of BFFGT. Lactobacillus appears to be the major regulator of both G. vaginalis and anaerobic bacteria. When additional organisms are added to the bacterial flora, they may add to or partially negate the inhibitory influence of Lactobacillus on the BFFGT. Inhibitor interrelationships appear to exist between coagulase-negative staphylococci and Staphylococcus aureus and the group B streptococci (GBS and other beta hemolytic streptococci. Facilitating interrelationships appear to exist between S. aureus and the GBS and selected Enterobacteriaceae.

Efficacy of florfenicol for treatment of clinical and subclinical bovine mastitis.

Science.gov (United States)

Wilson, D J; Sears, P M; Gonzalez, R N; Smith, B S; Schulte, H F; Bennett, G J; Das, H H; Johnson, C K

1996-04-01

To evaluate efficacy of florfenicol treatment for bovine mastitis caused by Streptococcus agalactiae, Staphylococcus aureus nonagalactiae streptococci, coagulase-negative staphylococci, Escherichia coli, Klebsiella sp, and others. Double blind study with cases randomly assigned to 1 of 2 treatment groups. 861 cows/10 commercial dairy farms. Experimental (750 mg of florfenicol) or control (200 mg of cloxacillin) treatment was administered by intramammary infusion every 12 hours for 3 treatment to all cases. Treatments were randomly assigned identified only by numerical labels. To retain blinding, the longer withdrawal time was adhered to for all cases. Cases remained in the study only if there was no other treatment. Quarter samples were recultured 14, 21, and 28 days later. If all samples after day 1 were culture negative, the case was defined as cured. If only 1 of the follow-up results was positive, the case was considered cured if the day-28 somatic cell count was mastitis treatment regimens poor efficacy may be partly attributable to the short duration of treatment.