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Sample records for cefoxitin

  1. Cefoxitin Injection

    Science.gov (United States)

    ... injection is used to treat infections caused by bacteria including pneumonia and other lower respiratory tract (lung) infections; and urinary tract, abdominal (stomach area), female reproductive organs, blood, ... by killing bacteria.Antibiotics such as cefoxitin injection will not work ...

  2. Effect of orally administered probenecid on the pharmacokinetics of cefoxitin.

    OpenAIRE

    Vlasses, P H; Holbrook, A M; Schrogie, J J; Rogers, J D; Ferguson, R K; Abrams, W B

    1980-01-01

    To characterize the effect of orally administered probenecid on the pharmacokinetics of cefoxitin in healthy male volunteers, we administered to one group of six subjects 2 g of cefoxitin by intravenous (i.v.) bolus either alone, with 1 g of probenecid concomitantly, or when 1 g of probenecid was administered 1 h previously by using a crossover design. Likewise, we administered to a second group of six subjects 2 g of cefoxitin intramuscularly (i.m.) together with 1 and 2 g of probenecid. Pro...

  3. Cephalosporin-induced leukopenia following rechallenge with cefoxitin.

    Science.gov (United States)

    Whitman, Craig B; Joseph, Jomy M; Sjoholm, Lars O

    2008-09-01

    To describe a case of cefazolin-induced leukopenia in a critically ill patient who developed this adverse reaction upon rechallenge with cefoxitin. A 22-year-old male was admitted after a motor vehicle crash. beta-Lactam therapy was initiated with vancomycin, cefepime, and metronidazole and, upon identification of methicillin-sensitive Staphylococcus aureus bacteremia 4 days later, therapy was narrowed to cefazolin 1 g every 12 hours. The dose was adjusted to 1 g every 12 hours during continuous venovenous hemodialysis. Imipenem was given for 2 days, resulting in a total of 18 days of beta-lactam treatment, at which time he developed significant leukopenia (white blood cell [WBC] count 0.9 x 10(3)/microL). Antimicrobial treatment was changed to tigecycline and continued for suspected pleural space infection. The patient's WBC count recovered within 4 days after the change in therapy. He was taken to surgery 8 days after cefazolin was discontinued and received perioperative prophylaxis with cefoxitin (total dose 3 g). Subsequently, the patient again became severely leukopenic (WBC count 2.4 x 10(3)/microL). Within a week after surgery, the patient developed septic shock secondary to multidrug-resistant Escherichia coli bacteremia and died. beta-Lactam-induced leukopenia is a rare but well-described adverse drug reaction. It is a cumulative dose-dependent phenomenon reported to occur most often after 2 weeks of therapy. The mechanism of leukopenia is thought to be secondary to either an immune-mediated response or direct bone marrow toxicity. Rechallenge with a different beta-lactam antibiotic has not been shown to consistently cause recurrent leukopenia. The case described here suggests an immune-related mechanism for the development of leukopenia. Use of the Naranjo probability scale determined the association between cephalosporin use and leukopenia to be probable. Cefazolin was a probable cause of this patient's leukopenia. It is important for clinicians to

  4. Susceptibility of clinical isolates of Bacteroides fragilis group strains to cefoxitin, cefoperazone and ticarcillin/clavulanate

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    PEIXOTO JÚNIOR Arnaldo Aires

    2000-01-01

    Full Text Available A total of 40 strains of the B. fragilis group was isolated from clinical specimens in two hospital centers in Fortaleza from 1993 to 1997. The most frequently isolated species was Bacteroides fragilis (19 strains and most isolates came from intra-abdominal and wound infections. The susceptibility profile was traced for cefoxitin, cefoperazone and ticarcillin-clavulanate by using the agar dilution reference method. All isolates were susceptible to ticarcillin-clavulanate (128/2mug/ml. Resistance rates of 15 and 70% were detected to cefoxitin (64mug/ml and cefoperazone (64mug/ml, respectively. Such regional results permit a better orientation in choosing this group of antibiotics for prophylaxis and therapy especially in relation to cefoxitin, which is frequently used in the hospital centers studied.

  5. Disk Diffusion Testing for Detection of Methicillin-Resistant Staphylococci: Does Moxalactam Improve upon Cefoxitin?

    Science.gov (United States)

    Bonjean, Marie; Hodille, Elisabeth; Dumitrescu, Oana; Dupieux, Céline; Nkoud Mongo, Christina; Allam, Camille; Beghin, Mathilde; Paris, Mickael; Borrel, Ophelie; Chardon, Hubert; Laurent, Fréderic; Rasigade, Jean-Philippe; Lina, Gerard

    2016-12-01

    Disk diffusion testing is widely used to detect methicillin resistance in staphylococci, and cefoxitin is currently considered the best marker for mecA-mediated methicillin resistance. In low-inoculum diffusion testing (colony suspension at 10 6 CFU/ml), the addition of moxalactam in combination with cefoxitin has been reported to improve on cefoxitin alone for the detection of methicillin-heteroresistant staphylococci. However, moxalactam is absent from EUCAST and CLSI guidelines, which use high-inoculum diffusion testing (colony suspension at 10 8 CFU/ml), calling into question the potential interest of including moxalactam in their recommendations. The inhibition zone diameters of cefoxitin and moxalactam, alone and in combination, were evaluated for concordance with mecA and mecC positivity in a large collection of clinical Staphylococcus isolates (611 Staphylococcus aureus, Staphylococcus lugdunensis, and Staphylococcus saprophyticus isolates and 307 coagulase-negative staphylococci other than S. lugdunensis and S. saprophyticus isolates, of which 22% and 53% were mecA-positive, respectively) and in 25 mecC-positive S. aureus isolates using high-inoculum diffusion testing. Receiver operating characteristic, sensitivity, and specificity analyses indicated that the detection of mecA- and mecC-positive and negative isolates did not improve with moxalactam, either alone or in combination with cefoxitin, compared to cefoxitin alone. These findings were similar in both the S. aureus/S. lugdunensis/S. saprophyticus group and in the coagulase-negative staphylococci group. Our results do not support the use of moxalactam as an additional marker of methicillin resistance when testing with high-inoculum disk diffusion. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  6. A Whole-Genome Sequencing Approach To Study Cefoxitin-Resistant Salmonella enterica Serovar Heidelberg Isolates from Various Sources.

    Science.gov (United States)

    Edirmanasinghe, Romaine; Finley, Rita; Parmley, E Jane; Avery, Brent P; Carson, Carolee; Bekal, Sadjia; Golding, George; Mulvey, Michael R

    2017-04-01

    This study characterized cefoxitin-resistant and -susceptible Salmonella enterica serovar Heidelberg strains from humans, abattoir poultry, and retail poultry to assess the molecular relationships of isolates from these sources in Québec in 2012. Isolates were collected as part of the Canadian Integrated Program for Antimicrobial Resistance Surveillance (CIPARS). All isolates were subjected to antimicrobial susceptibility testing, PCR for CMY-2, pulsed-field gel electrophoresis (PFGE), and whole-genome sequencing (WGS). A total of 113 S Heidelberg isolates from humans ( n = 51), abattoir poultry ( n = 18), and retail poultry ( n = 44) were studied. All cefoxitin-resistant isolates ( n = 65) were also resistant to amoxicillin-clavulanic acid, ampicillin, ceftiofur, and ceftriaxone, and all contained the CMY-2 gene. PFGE analysis showed that 111/113 (98.2%) isolates clustered together with ≥90% similarity. Core genome analysis using WGS identified 13 small clusters of isolates with 0 to 4 single nucleotide variations (SNVs), consisting of cefoxitin-resistant and -susceptible human, abattoir poultry, and retail poultry isolates. CMY-2 plasmids from cefoxitin-resistant isolates all belonged to incompatibility group I1. Analysis of IncI1 plasmid sequences revealed high identity (95 to 99%) to a previously described plasmid (pCVM29188_101) found in Salmonella Kentucky. When compared to pCVM29188_101, all sequenced cefoxitin-resistant isolates were found to carry 1 of 10 possible variant plasmids. Transmission of S Heidelberg may be occurring between human, abattoir poultry, and retail poultry sources, and transmission of a common CMY-2 plasmid may be occurring among S Heidelberg strains with variable genetic backgrounds. © Crown copyright 2017.

  7. Development and Characterization of Cefoxitin Loaded D,L-PLA Nanoparticles

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    Sílvia Regina Pengo Machado

    2010-12-01

    Full Text Available Nanoparticles containing cefoxitin (CEF made of D,L-PLA (PLA were designed by a multiple emulsion/solvent evaporation method. The particles were extensively evaluated in relation to morphology, encapsulation efficiency, drug-polymer interactions as well as in vitro drug release kinetics. Nanoparticles were spherical in shape and isolated, with a mean diameter of about 600 nm. The thermal behaviour (DSC of CEF-containing nanoparticles suggested that the drug was dispersed at a molecular level within the system. The drug encapsulation efficiency in the system for a CEF concentration of 30 mg/mL was 5.5%, as assessed after the drug extraction, by a validated HPLC method. This low encapsulation efficiency is understandable, since CEF is highly hydrophilic. The in vitro assays showed a strong sustained drug release profile from the nanoparticles with kinetics following pure Fickian diffusion. Keywords: Nanoparticles. Controlled release. D,L-PLA. Cefoxitin. In vitro release. RESUMO Desenvolvimento e Caracterização de Nanopartículas de D,L-PLA contendo Cefoxitina As nanopartículas de D, L-PLA (PLA contendo cefoxitina (CEF foram preparadas pelo método de emulsão múltipla / evaporação do solvente. As partículas foram avaliadas em relação à morfologia, à eficiência de encapsulação, às interações polímero-fármaco, bem como à cinética de liberação do fármaco in vitro . As nanopartículas são esféricas e isoladas, com um diâmetro médio de cerca de 600 nm. O comportamento térmico (DSC das nanopartículas contendo CEF sugeriu que o fármaco está disperso em um nível molecular dentro do sistema. A eficiência de encapsulação do fármaco no sistema quando a concentração de CEF é 30 mg / mL foi de 5,5%, determinada após a extração de fármaco, através de um método de HPLC validado. Esta baixa eficiência de encapsulação é compreensível, uma vez que a CEF é altamente hidrofílica. Os ensaios in vitro mostraram um

  8. Comparison of Oxacillin and Cefoxitin for the Detection of mecAGene to Determine Methicillin Resistance in Coagulase Negative Staphylococci(CoNs).

    Science.gov (United States)

    Shah, Dania Aijaz; Wasim, Shehnaz; Abdullah, Farhan Essa

    2017-08-01

    The aim of the study was to compare the effectiveness of Cefoxitin with that of Methicillin/Oxacillin in the determination of mecAgene in Methicillin resistant Coagulase-negative staphylococci(CoNS). We assessed 57 CoNS isolates for mecA gene via PCR, which were subsequently subjected to Methicillin/Oxacillin and Cefoxitin disc diffusion test. These methods are simple, inexpensive and easily available compared to PCR despite less specificity. Out of 41 mecApositive species, 33 (80.5%) were resistant to Methicillin/Oxacillin. Cefoxitin-resistance was seen in all 41 (100%) mecApositive samples. Two (12.5%) mecAnegative isolates of S.saprophyticuswere Methicillin/Oxacillin resistant, but were Cefoxitin sensitive. Four (9.7%) isolates of S.saprophyticus, three (7.3%) of S.epidermidisspecies, and one (2.4%) S.haemolyticusthat were mecApositive were sensitive to Methicillin/Oxacillin but resistant to Cefoxitin. Cefoxitin resistance provides a more accurate picture of mecAgene positivity as compared to Methicillin and Oxacillin.

  9. Cefoxitin resistance mediated by loss of a porin in clinical strains of Klebsiella pneumoniae and Escherichia coli

    Directory of Open Access Journals (Sweden)

    Ananthan S

    2005-01-01

    Full Text Available PURPOSE: Porins are outer membrane protein (OMP that form water filled channels that permit the diffusion of small hydrophilic solutes like -lactam antibiotics across the outer membrane. Two major porins that facilitate diffusion of antimicrobials have been described in Klebsiella spp. and Escherichia coli. The present study was carried out to examine the role of porins among Extended Spectrum -Lactamase (ESBL and AmpC -Lactamase positive strains of Klebsiella spp. and E.coli. METHODS: Preparation of OMP from phenotypically characterized clinical isolates K.pneumoniae and E.coli and the separation of the proteins by sodium dodecyl sulfate - polyacrylamide gel electrophoresis were performed as per a previously described procedure. RESULTS: OMP analysis revealed that cefoxitin and ceftazidime resistance was mediated by loss of a porin Omp K35 in the isolates of K.pneumoniae and E.coli. CONCLUSIONS: Loss of porin mediated resistance mechanism against cefoxitin was observed among the multidrug resistant K.pneumoniae and E.coli.

  10. [Comparison of oxacillin, cefoxitin, ceftizoxime, and moxalactam disk diffusion methods for detection of methicillin susceptibility in staphylococci].

    Science.gov (United States)

    Özel, Gönül; Aslan, Volkan; Bahar Erdem, Gül; Çağatay, Mustafa; Sencan, Irfan; Mert, Ali

    2011-04-01

    Penicillin binding protein 2a/2' (PBP2a/PBP2') which is encoded by the mecA gene, is responsible for the methicillin resistance in staphylococci. Detection of methicillin resistance with phenotypic methods is still a problem especially because of heterogenous expression of mecA gene. Although mecA gene determination by polymerase chain reaction is considered as the gold standard method, molecular tests are not easily applied in all routine laboratories. Thus, for the rapid and accurate diagnosis of MRSA strains, easy and practical phenotypic tests are still required. This study was conducted to compare the oxacillin (OX), cefoxitin (CFX), ceftizoxime (CZX), and moxolactam (MOX) susceptibility testing by disk diffusion method for the detection of methicillin resistance in staphylococci. A total of 247 staphylococci (125 Staphylococcus aureus and 122 coagulase-negative staphylococci; CNS) isolated from various clinical specimens (114 wound and soft tissue materials, 51 urine, 48 blood, 30 respiratory tract, and four other samples) of inpatients and outpatients, were included in this study. PBP2a latex agglutination test was used as the reference method for the recognition of methicillin resistance; four antibiotic disks tested and sensitivity, specificity, positive and negative predictive values (PPV and NPV) were determined for each of them. According to PBP2a latex agglutination test 66 (54.1%) of CNS and 53 (42.4%) of S.aureus isolates were found methicillin- resistant. OX and MOX disks detected 113 (63 CNS and 50 S.aureus) methicillin-resistant strain out of 119 PBP2a positive isolates, where CFX and CZX disks detected 110 (60 CNS and 50 S.aureus) of them. Among 128 PBP2a negative isolates, 123 (52 CNS and 71 S.aureus) were detected as susceptible with OX, 127 (55 CNS and 72 S.aureus) with CFX and CZX, 126 (54 CNS and 72 S.aureus) with MOX. According to these results, the sensitivities and specificities of OX, CFX, CZX, and MOX disks were; 95.4% and 92.8%, 90

  11. Comparison of cycloserine-cefoxitin-fructose agar (CCFA) and taurocholate-CCFA for recovery of Clostridium difficile during surveillance of hospitalized patients.

    Science.gov (United States)

    Bliss, D Z; Johnson, S; Clabots, C R; Savik, K; Gerding, D N

    1997-09-01

    The effectiveness of cycloserine-cefoxitin-fructose agar (CCFA) and taurocholate-CCFA (TCCFA) in isolating Clostridium difficile from swabs of the rectum or stools from 184 hospitalized patients who were monitored weekly and when they had diarrhea was compared. The number of surveillance time points ranged from two to eight per patient over a period of 4 to 34 days per patient, totalling 621 comparisons of the media. C. difficile was isolated more frequently by TCCFA than CCFA at seven of eight surveillance points, a significant trend (O'Brien test, p = 0.002). This difference reached statistical significance at the second surveillance time point when the prevalence of C. difficile was sufficiently high. At the second surveillance point, C. difficle was isolated only by TCCFA in 7 of 184 comparisons of the media, only by CCFA in none of the comparisons, and by both media in 19 comparisons (p = 0.016). C. difficle was first isolated at an earlier surveillance time point on TCCFA in 11 of 36 patients and on CCFA first only once (p = 0.005). Use of TCCFA media increased the rapidity and sensitivity of culture for C. difficle when doing patient surveillance but did not increase sensitivity when diagnosing patients with diarrhea.

  12. Carbapenem and cefoxitin resistance of Klebsiella pneumoniae strains associated with porin OmpK36 loss and DHA-1 β-lactamase production

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    Weifeng Shi

    2013-01-01

    Full Text Available Clinical isolates of carbapenem-resistant Klebsiella pneumoniae (K. pneumoniae strains are being increased worldwide. Five pan-resistant K. pneumoniae strains have been isolated from respiratory and ICU wards in a Chinese hospital, and reveal strong resistance to all β-lactams, fluoroquinolones and aminoglycosides. Totally 27 β-lactamase genes and 2 membrane pore protein (porin genes in 5 K. pneumoniae strains were screened by polymerase chain reaction (PCR. The results indicated that all of 5 K. pneumoniae strains carried blaTEM-1 and blaDHA-1 genes, as well as base deletion and mutation of OmpK35 or OmpK36 genes. Compared with carbapenem-sensitive isolates by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE, the resistant isolates markedly lacked the protein band of 34-40 kDa, which might be the outer membrane proteins of OmpK36 according to the electrophoresis mobility. In addition, the conjugation test was confirmed that blaDHA-1 mediated by plasmids could be transferred between resistant and sensitive strains. When reserpine (30 µg/mL and carbonyl cyanide m-chlorophenylhydrazone (CCCP (50 µg/mL were added in imipenem and meropenem, the MICs had no change against K. pneumoniae strains. These results suggest that both DHA-1 β-lactamase and loss or deficiency of porin OmpK36 may be the main reason for the cefoxitin and carbapenem resistance in K. pneumoniae strains in our hospital.

  13. Methicillin-resistant Staphylococcus aureus isolates with SCCmec type V and spa types t437 or t1081 associated to discordant susceptibility results between oxacillin and cefoxitin, Central Taiwan.

    Science.gov (United States)

    Ho, Cheng-Mao; Lin, Chien-Yu; Ho, Mao-Wang; Lin, Hsiao-Chuan; Chen, Chao-Jung; Lin, Lee-Chung; Lu, Jang-Jih

    2016-12-01

    Staphylococcus aureus isolates with discordant susceptibility results between oxacillin and cefoxitin obtained using automated microbiology systems are infrequently observed. From April 2013 to December 2014, 1956 methicillin-resistant S. aureus (MRSA) and 1761 methicillin-susceptible S. aureus isolates were obtained from different patients. Forty isolates (1.1% and 2% in case of S. aureus and MRSA, respectively) with discordant susceptibility results (oxacillin susceptible and cefoxitin resistant) and carrying mecA gene were obtained. Except 2 SCCmec type IV isolates, 38 MRSA isolates were all SCCmec type V (V T or non-V T ), which were further divided into V T (n=22) and non-V T (n=16). The most common spa type in V T and non-V T isolates were t437 (n=19) and t1081 (n=13), respectively. Only 55% of patients received effective antimicrobial agents; 2 mortalities were not attributable to MRSA infection. Using standard agar dilution, 17 MRSA isolates (0.46% and 0.87% in case of S. aureus and MRSA, respectively) had oxacillin MIC in the susceptible ranges (oxacillin-susceptible MRSA [OS-MRSA]); all carried SCCmec type V (V T , n=8; non-V T , n=9). The most common spa-MLST types of OS-MRSA in V T and non-V T were t437-ST59 (n=4) and t1081-ST45 (n=7), respectively. Concomitant testing by both cefoxitin- and oxacillin-based methods is a practical strategy for OS-MRSA detection in the clinical laboratories. Continuous monitoring of OS-MRSA isolates is necessary to elucidate their impact in clinical infectious diseases. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Evaluation of ceftiofur and cefquinome for phenotypic detection of methicillin resistance in Staphylococcus aureus using disk diffusion testing and MIC-determinations

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Skov, R. L.

    2010-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) have emerged in animals. Testing 98 mecA negative and 71 mecA positive S. aureus we compared the usefulness of ceftiofur and cefquinome to cefoxitin, for detection of MRSA and found that these cephalosporins are not as efficient as cefoxitin....

  15. Detection of methicillin-resistant coagulase-negative staphylococci by the Vitek 2 system.

    Science.gov (United States)

    Johnson, Kristen N; Andreacchio, Kathleen; Edelstein, Paul H

    2014-09-01

    The accurate performance of the Vitek 2 GP67 card for detecting methicillin-resistant coagulase-negative staphylococci (CoNS) is not known. We prospectively determined the ability of the Vitek 2 GP67 card to accurately detect methicillin-resistant CoNS, with mecA PCR results used as the gold standard for a 4-month period in 2012. Included in the study were 240 consecutively collected nonduplicate CoNS isolates. Cefoxitin susceptibility by disk diffusion testing was determined for all isolates. We found that the three tested systems, Vitek 2 oxacillin and cefoxitin testing and cefoxitin disk susceptibility testing, lacked specificity and, in some cases, sensitivity for detecting methicillin resistance. The Vitek 2 oxacillin and cefoxitin tests had very major error rates of 4% and 8%, respectively, and major error rates of 38% and 26%, respectively. Disk cefoxitin testing gave the best performance, with very major and major error rates of 2% and 24%, respectively. The test performances were species dependent, with the greatest errors found for Staphylococcus saprophyticus. While the 2014 CLSI guidelines recommend reporting isolates that test resistant by the oxacillin MIC or cefoxitin disk test as oxacillin resistant, following such guidelines produces erroneous results, depending on the test method and bacterial species tested. Vitek 2 cefoxitin testing is not an adequate substitute for cefoxitin disk testing. For critical-source isolates, mecA PCR, rather than Vitek 2 or cefoxitin disk testing, is required for optimal antimicrobial therapy. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  16. Comparative analysis of phenotypic and genotypic detection of methicillin resistance among Staphylococcus aureus

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    Tulin Demir

    2016-01-01

    Full Text Available Aims: Staphylococcus aureus is a common pathogen causing a wide range of infections ranging from mild skin and soft tissue infections to severe, life-threatening infections. Accuracy in the detection of methicillin resistance is important to avoid treatment failures. The aim of this study was to compare the results of phenotypic and genotypic test methods to detect methicillin resistance and also to determine the antimicrobial susceptibilities. Materials and Methods: Two hundred and forty-two S. aureus strains isolated from skin and soft tissue samples were analyzed for methicillin resistance using oxacillin and cefoxitin disk diffusion (DD, oxacillin screen agar test, cefoxitin E-test, and mecA gene polymerase chain reaction (PCR. Results: 77 of 242 S. aureus isolates were mecA positive. Oxacillin, cefoxitin DD, oxacillin screen agar test and cefoxitin E-test exhibited sensitivities as 98.7%, 98.7%, 100%, 100%, and specificities as 96.9%, 97.5%, 96.9%, 97.5%, respectively. Conclusion: Results of oxacillin screen agar and cefoxitin DD test were in concordance with mecA gene PCR. Thus, it is determined that especially cefoxitin test can be an alternative to PCR in routine.

  17. Comparison of Disk Diffusionand

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    Mohsen Rezazadeh

    2014-08-01

    Full Text Available Background: Increasing prevalence of Methicillin-resistant Staphylococcus aureus (MRSA in different communities is clearly visible. Because of this, treatment of patients with infections caused by those bacteria has fallen into critical troubles .Current study, therefore, is aimed to compare phenotypic (disk diffusion and genotypic (PCR methods for fast diagnosis of methicillin-resistant strains, isolated from patients of Arak Central Hospital Materials and Methods:In a cross sectional study whithin one year of period , a total of 100 samples were taken and tested from the patients of Arak hospital (located in the central part of Iran . Isolates' sensitivity to Cefoxitin Disk and Oxacillin was confirmed through disk diffusion. Using PCR , the isolates were tested for the presence of mecA gene. Results were compared from the points of sensitivity and specificity by application of chi square test in SPSS software.. Results: Seventy five 75% out of the total 100 samples (through oxacillin disk diffusion method , already isolated from patients were resistant to oxacillin. Meanwhile, 83(83% of cefoxitin disk diffusion method samples’ were resistant to cefoxitin. Three resistant samples to cefoxitin were negative for mecA gene and 80 (80% samples were positive for mecA gene using PCR. Sensitivity were respectively 93.75% , 100% , and specificity were 100% and 100% , 85% , 100 Conclusion: Findings indicate that oxacillin disk diffusion method is a simple phenotypic method, however, it has lower sensitivity compared to cefoxitin disk diffusion and polymerase chain reaction (PCR methods. Therfore, it is not recommended for detection of Methicillin-resistant Staphylococcus aureus (MRSA. Existence of strains resistant to cefoxitin without mecA gene, shows the outset of another type of resistance or mutation in Methicillin-resistant Staphylococcus aureus (MRSA .

  18. Evaluation and comparison of tests to detect methicillin resistant S. aureus

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    Mathews Anila

    2010-01-01

    Full Text Available Background and Objectives: Phenotypic methods for detection of methicillin resistant Staphylococcus aureus (MRSA have been compared with the gold standard which, as of now, is by the detection of mecA gene and femA gene by polymerase chain reaction (PCR. Discrepancies in detection have an adverse effect on patient management, thereby highlighting the importance of accuracy in detection. Our study aims to evaluate the efficacy of cefoxitin disk diffusion test to detect MRSA and compare it with other phenotypic and molecular methods. Methodology; The study was conducted from June 2006 to December 2007 and included 610 Staphylococcus aureus (S. aureus isolates obtained from clinical samples. All isolates were tested for MRSA using oxacillin screen agar plates with 6 µg/ml of oxacillin, cefoxitin disk diffusion using 30 µg disk and MIC of oxacillin. Selected isolates (55 were tested for presence of mecA gene and Fem A gene by PCR. Results: Out of 610 isolates, MRSA was identified in 34.09% by cefoxitin disk diffusion, 34.9% by oxacillin screen agar, 34.4% by MIC and 37.3% by oxacillin disk diffusion. When selected isolates were tested with molecular methods, the cefoxitin disk diffusion and PCR tests were comparable. Discussion: Prevalence of MRSA (34.09% is quite high as in other studies. The oxacillin disk diffusion test which was used routinely earlier is showing low specificity (56%. Among all phenotypic methods, cefoxitin disk diffusion and PCR alone have similar sensitivity and specificity. Conclusion: Results of cefoxitin disk diffusion test are in concordance with the PCR for mecA gene. Thus, the test can be an alternative to PCR for detection of MRSA in resource constraint settings.

  19. Multidrug-Resistant Bacteroides fragilis Bacteremia in a US Resident: An Emerging Challenge

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    Cristian Merchan

    2016-01-01

    Full Text Available We describe a case of Bacteroides fragilis bacteremia associated with paraspinal and psoas abscesses in the United States. Resistance to b-lactam/b-lactamase inhibitors, carbapenems, and metronidazole was encountered despite having a recent travel history to India as the only possible risk factor for multidrug resistance. Microbiological cure was achieved with linezolid, moxifloxacin, and cefoxitin.

  20. Detection of ESBL among ampc producing enterobacteriaceae ...

    African Journals Online (AJOL)

    Methods: A total of 259 clinical isolates of Enterobacteriaceae were isolated and screened for ESBL production by (i) CLSI double-disk diffusion method (ii) cefepime- clavulanic acid method (iii) boronic disk potentiation method. AmpC production was detected using cefoxitin alone and in combination with boronic acid and ...

  1. Comparison of chromogenic media to BD GeneOhm methicillin-resistant Staphylococcus aureus (MRSA) PCR for detection of MRSA in nasal swabs.

    Science.gov (United States)

    Bischof, Larry J; Lapsley, Linda; Fontecchio, Karen; Jacosalem, Dollie; Young, Carol; Hankerd, Rosemary; Newton, Duane W

    2009-07-01

    To select a method for detecting methicillin-resistant Staphylococcus aureus (MRSA) in nasal swabs, we compared BD GeneOhm MRSA PCR and various culture media (mannitol salt agar with cefoxitin, MRSASelect, CHROMagar MRSA, and Spectra MRSA). While PCR detection of MRSA was more rapid, MRSASelect and Spectra MRSA demonstrated performance equivalent to that of PCR with maximal detection at 24 h.

  2. Isolation, identification and antimicrobial suscep- tibility profiles of ...

    African Journals Online (AJOL)

    (HIMEDIA M111A, India), Methyl red-Voges-Proskauer (HIMEDIA M070, In- dia) broth and then incubated for 24 to 48 hrs at ... of eleven antimicrobials. amoxicillin (AML). (25 μg), ampicillin (AMP) (10 μg), cefoxitin (FOX) (30 μg), chloramphenicol (C) ..... Evolution of host adaptation in. Salmonella enterica. Infect. Immun., 66 ...

  3. Detection of Amp C Beta Lactamases in Clinical Isolates of ...

    African Journals Online (AJOL)

    A total of 81 consecutive non repetitive clinical isolates of Escherichia coli (n=40) and Klebsiella spp. (n=41) were screened for AmpC production by disc diffusion method using cefoxitin (30 Zg) disc and confirmed by inhibitor based test using boronic acid as inhibitor. A total of 16 E.coli isolates (40%) and 16 Klebsiella ...

  4. Evaluation of Two New Chromogenic Media, CHROMagar MRSA and S. aureus ID, for Identifying Staphylococcus aureus and Screening Methicillin-Resistant S. aureus

    OpenAIRE

    Hedin, Göran; Fang, Hong

    2005-01-01

    Thirty-nine methicillin-resistant Staphylococcus aureus (MRSA) isolates with diverse genetic backgrounds and two reference strains were correctly identified as S. aureus on CHROMagar MRSA and S. aureus ID media. Growth inhibition on CHROMagar MRSA was noted. A combination of cefoxitin disk and S. aureus ID was found suitable for rapid MRSA screening.

  5. Role of inducers in detection of blaPDC-mediated oxyimino-cephalosporin resistance in Pseudomonas aeruginosa

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    Birson Ingti

    2017-01-01

    Interpretation & conclusions: P. aeruginosa harbouring inducible (chromosomal and plasmid-mediated AmpC β-lactamase is a matter of concern as it may limit therapeutic option. Using cefoxitin-ceftazidime-based test is simple and may be used for detecting inducible AmpC β-lactamase amongst P. aeruginosa.

  6. Increased expression levels of chromosomal AmpC β-lactamase in clinical Escherichia coli isolates and their effect on susceptibility to extended-spectrum cephalosporins

    NARCIS (Netherlands)

    Paltansing, Sunita; Kraakman, Margriet; van Boxtel, H.A.M.; Kors, Ivo; Wessels, Els; Goessens, Wil; Tommassen, J.P.M.; Bernards, Alexandra

    Forty-nine clinical Escherichia coli isolates, both extended-spectrum β-lactamase (ESBL) negative and ESBL positive, were studied to investigate whether increased AmpC expression is a mechanism involved in cefoxitin resistance and if this influences the third-generation cephalosporin activity. Nine

  7. Prevalence and molecular characterization of methicillin resistance among Coagulase-negative Staphylococci at a tertiary care center.

    Science.gov (United States)

    Bhatt, Puneet; Tandel, Kundan; Singh, Alina; Kumar, M; Grover, Naveen; Sahni, A K

    2016-12-01

    Methicillin-resistant Coagulase-negative Staphylococci (MR-CoNS) have emerged as an important cause of nosocomial infections especially in patients with prosthetic devices and implants. This study was conducted with an aim to determine the prevalence of methicillin resistance among CoNS isolates at a tertiary care center by both phenotypic and genotypic methods. This cross sectional study was carried out from September 2011 to February 2014 in which 150 non-repetitive clinical isolates of CoNS were identified at the species level by conventional phenotypic methods. Cefoxitin disk (30 μg) diffusion testing was used to determine methicillin resistance and confirmed by detection of mec A gene by polymerase chain reaction (PCR). Out of 150 CoNS isolates, 51 were methicillin resistant by cefoxitin disk diffusion method. Out of these 51 isolates, mec A gene was detected only in 45 isolates. Moreover, mec A gene was also detected in 4 isolates, which were cefoxitin sensitive. Thus, the prevalence of methicillin resistance among CoNS was found to be 32.7% by PCR. The prevalence of methicillin resistance among Coagulase-negative Staphylococci (CoNS) was 32.7% by PCR detection of mec A gene. The sensitivity and specificity of cefoxitin disk diffusion method against mec A gene detection by PCR were found to be more than 90%. It can be concluded from this study that cefoxitin disk diffusion test can be used as a useful screening method to detect methicillin resistance among CoNS isolates. However, detection of mec A gene by PCR remains a more accurate method of detecting methicillin resistance among CoNS.

  8. Comparison of different phenotypic methods of detection of methicillin resistance in staphylococcus aureus with the molecular detection of mec-a gene

    International Nuclear Information System (INIS)

    Zeeshan, M.; Jabeen, K.; Irfan, S.; Parween, Z.; Zafar, A.

    2007-01-01

    To evaluate accuracy, cost-effectiveness and ease to perform different phenotypic methods i.e. Cefoxitin 30 micro g disc, Oxacillin 1micro g disc and Oxacillin agar screening plate (6 micro g/ml) for early and accurate identification of MRSA by comparing with the detection of mec-A gene in our clinical isolates. Out of 200 clinical samples, conventional Polymerase Chain Reaction (PCR) was done on 62 pure biochemically identified S. aureus isolates for mec-A gene detection. Phenotypic methods for detecting methicillin sensitivity (Cefoxitin 30 microg disc, Oxacillin 1 micro g disc and Oxacillin agar screening plate) were also used according to the recommended incubation time, duration and temperature on the same isolates. Out of 62 isolates of S. aureus, mec-A gene were detected (MRSA) in 32, whereas 30 were mec-A gene negative (MSSA). Cefoxitin disc and agar screening plate correctly identify all MRSA isolates with the sensitivity and specificity of 100%. Single isolate was false, positively detected as sensitive with Oxacillin 1g disc, due to which, the sensitivity and negative predictive value of this method were reduced to 96.9% and 96.8% respectively, while positive predictive value and specificity remained 100%. Comparing different phenotypic methods for MRSA screening in routine microbiology laboratory, Cefoxitin disc and Oxacillin agar screening has better sensitivity and specificity comparative to Oxacillin disc. However, Cefoxitin disc can be preferred especially for small laboratories because it is easy to perform, do not require special technique and media preparation is consequently more cost-effective. (author)

  9. MULTI-DRUG RESISTANCE PATTERNS OF ENTERIC BACTERIA IN TWO POPULATIONS OF FREE-RANGING EASTERN BOX TURTLES (TERRAPENE CAROLINA CAROLINA).

    Science.gov (United States)

    Rasmussen, Cari; Allender, Matthew C; Phillips, Christopher A; Byrd, John; Lloyd, Terrell; Maddox, Carol

    2017-09-01

    Gram-negative isolates (n = 84) from 71% of free-ranging Eastern box turtles (Terrapene carolina carolina) in Illinois and Tennessee, United States, demonstrated resistance to at least one antibiotic while 30% of isolates demonstrated resistance to two or more antibiotics. Resistance was observed against cefoxitin, amoxicillin-clavulanic acid, cefazolin, ampicillin, ticarcillin, cefovecin, and ceftiofur. Gram-positive bacteria were isolated from 49 turtles, and all were observed to be resistant to two or more antibiotics. Gram-positive isolate resistance was observed to penicillin, cefoxitin, oxacillin, clindamycin, amikacin, enrofloxacin, cefovecin, ceftiofur, cefazolin, marbofloxacin, gentamicin, erythromycin, trimethoprim-sulfamethoxazole, and chloramphenicol. Health parameters including packed cell volume, total white blood cell count (WBC), total solids (TS), and weight were not significantly different based on antibiotic resistance patterns; however, decreasing WBC and TS were observed when the number of antibiotic-resistant detections in Gram-positive bacteria increased.

  10. Survey of Neisseria gonorrhoeae Antimicrobial Susceptibility in Ontario

    Directory of Open Access Journals (Sweden)

    Vivian G Loo

    1990-01-01

    Full Text Available The minimal inhibitory concentrations (MICs of penicillin, tetracycline, erythromycin, cefoxitin, ceftriaxone and spectinomycin were determined for 300 consecutive strains of Neisseria gonorrhoeae collected from physicians’ offices in Ontario. Only four isolates were found to produce beta-lactamase. Of the remaining 296 isolates, five (1.7% had penicillin MICs greater than or equal to 1 mg/L, 78 (26.3% had tetracycline MICs greater than or equal to 1 mg/L, 13 (4.4% had cefoxitin MICs greater than or equal to 1 mg/L and 43 (14.5% had erythromycin MICs greater than or equal to 1 mg/L. Two isolates (0.7% had high level tetracycline resistance with MICs greater than or equal to 16 mg/L. All N gonorrhoeae isolates were susceptible to ceftriaxone and to spectinomycin.

  11. Comparison of Chromogenic Media to BD GeneOhm Methicillin-Resistant Staphylococcus aureus (MRSA) PCR for Detection of MRSA in Nasal Swabs▿

    Science.gov (United States)

    Bischof, Larry J.; Lapsley, Linda; Fontecchio, Karen; Jacosalem, Dollie; Young, Carol; Hankerd, Rosemary; Newton, Duane W.

    2009-01-01

    To select a method for detecting methicillin-resistant Staphylococcus aureus (MRSA) in nasal swabs, we compared BD GeneOhm MRSA PCR and various culture media (mannitol salt agar with cefoxitin, MRSASelect, CHROMagar MRSA, and Spectra MRSA). While PCR detection of MRSA was more rapid, MRSASelect and Spectra MRSA demonstrated performance equivalent to that of PCR with maximal detection at 24 h. PMID:19439540

  12. Mixed Infections and their Control

    Science.gov (United States)

    1983-04-29

    penicillin-sensitive anaerobes 28 anid P. aeruginosa. 310 CEPHALOSPORINS . The antimicrobial spectrum of first - generation cephalosporins against anaerobes...therefore effective against B. fragilis. The third-generation cephalosporins have a broad spectrum of activity against enteric Gram-negative bacilli and...resistant by virtue of ceoh:,-iosporinase production 𔃼. Cefoxitin, a second-generation cephalosporin , is relatively resistent to this enzyme and is

  13. Increased expression levels of chromosomal AmpC β-lactamase in clinical Escherichia coli isolates and their effect on susceptibility to extended-spectrum cephalosporins.

    Science.gov (United States)

    Paltansing, Sunita; Kraakman, Margriet; van Boxtel, Ria; Kors, Ivo; Wessels, Els; Goessens, Wil; Tommassen, Jan; Bernards, Alexandra

    2015-02-01

    Forty-nine clinical Escherichia coli isolates, both extended-spectrum β-lactamase (ESBL) negative and ESBL positive, were studied to investigate whether increased AmpC expression is a mechanism involved in cefoxitin resistance and if this influences the third-generation cephalosporin activity. Nine of 33 (27.2%) cefoxitin-resistant (minimum inhibitory concentration [MIC] >8 mg/L) isolates showed hyperproduction of chromosomal AmpC (c-AmpC) based on (1) at least two positive tests using AmpC inhibitors, (2) mutations in the promoter/attenuator regions, and (3) a 6.1- to 163-fold increase in c-ampC expression by quantitative reverse transcription-polymerase chain reaction. In ESBL-negative isolates, MICs of ceftazidime and cefotaxime were mostly above the wild-type (WT) level, but below the S/I breakpoint (EUCAST guideline), except for one isolate with MICs of 4 mg/L. No plasmid-mediated AmpCs were found. Periplasmic extracts of nine c-AmpC hyperproducers were preincubated with or without cefuroxime or ceftazidime and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Cefuroxime and ceftazidime were stable to hydrolysis but acted as inhibitors of the enzyme. None of these isolates showed loss of porins. Thus, cefoxitin resistance has low specificity for detecting upregulated c-AmpC production. c-AmpC hyperproducing E. coli is mostly still susceptible to third-generation cephalosporins but less than WT E. coli. Surveillance of cefoxitin-resistant E. coli to monitor developments in the activity of third-generation cephalosporins against c-AmpC hyperproducers is warranted.

  14. Effectiveness of the antimicrobial removal device, BACTEC 16B medium, and thiol broth in neutralizing antibacterial activities of imipenem, norfloxacin, and related agents.

    OpenAIRE

    Weinberg, E; Shungu, D L; Gadebusch, H H

    1984-01-01

    The Antimicrobial Removal Device (ARD), BACTEC 16B medium, and Thiol broth were evaluated for their effectiveness in reducing the activity of imipenem (IPM), cefoxitin, moxalactam, and ceftazidime in blood samples. In addition, the capability of the ARD and Thiol broth to bind norfloxacin and the ARD to bind oxolinic and nalidixic acids in urine samples was investigated. At the highest concentrations of the drugs tested (32 micrograms/ml for the four beta-lactams and 256 micrograms/ml for the...

  15. Methicillin-resistant Staphylococcus aureus expressing low-level methicillin resistance may not be detected by the VITEK2® system.

    Science.gov (United States)

    Al Nakib, Malik; Réglier-Poupet, Hélène; Longo, Magalie; Adam, Jean-Marie; Raymond, Josette; Zambardi, Gilles; Tazi, Asmaa; Poyart, Claire

    2012-02-01

    Low-level methicillin-resistant Staphylococcus aureus may be difficult to detect with the VITEK® 2 system (VK2). Here, we suggest that S. aureus exhibiting VK2-oxacillin MIC of 1 or 2 mg/L and a negative cefoxitin screen should be tested for the presence of mecA or its gene product. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. Evaluation of a commercial immunochromatographic assay for rapid routine identification of PBP2a-positive Staphylococcus aureus and coagulase-negative staphylococci.

    Science.gov (United States)

    Dupieux, Céline; Trouillet-Assant, Sophie; Tasse, Jason; Freydière, Anne-Marie; Raulin, Olivia; Roure-Sobas, Chantal; Salord, Hélène; Tigaud, Sylvestre; Laurent, Frédéric

    2016-11-01

    We evaluated the performance of an immunochromatographic assay (PBP2a Culture Colony Test - Alere™), detecting protein-binding penicillin 2a on staphylococci primary isolates in only 6minutes. The assay is highly sensitive for the direct detection of MRSA on various culture media whereas it requires cefoxitin induction for methicillin-resistant coagulase-negative staphylococci. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Characterization of metallo-beta-lactamase VIM-27, an A57S mutant of VIM-1 associated with Klebsiella pneumoniae ST147.

    Science.gov (United States)

    Papagiannitsis, C C; Kotsakis, S D; Petinaki, E; Vatopoulos, A C; Tzelepi, E; Miriagou, V; Tzouvelekis, L S

    2011-07-01

    VIM-27 metallo-β-lactamase, an Ala(57) → Ser variant of VIM-1, was identified in three Klebsiella pneumoniae isolates belonging to sequence type 147. bla(VIM-27) was part of a class 1 integron carried by non-self-transferable plasmids. Kinetic parameters and MIC determinations indicated that VIM-27 hydrolyzed most β-lactams, especially imipenem and cefoxitin, less effectively than VIM-1.

  18. Detection of Amp C genes encoding for beta-lactamases in Escherichia coli and Klebsiella pneumoniae

    Directory of Open Access Journals (Sweden)

    M Shanthi

    2012-01-01

    Full Text Available Purpose : Amp C beta-lactamase are Ambler class C enzymes that confer resistance to extended spectrum cephalosporins and are not inhibited by beta-lactamase inhibitors. Their detection is crucial, since the phenotypic tests are not standardised leading to ambiguity in interpretation of results. This study was done to detect the types of Amp C prevalent in Escherichia coli and Klebsiella pneumoniae by multiplex polymerase chain reaction (PCR. Materials and Methods : Seventy-seven consecutive cefoxitin resistant clinical isolates of E. coli (n = 25 and K. pneumoniae (n = 52 were included in the study. Antibiotic susceptibility testing to various classes of antibiotics was performed by disc diffusion using Clinical Laboratory Standards Institute (CLSI guidelines. Minimum inhibitory concentration (MIC to cefoxitin, imipenem and meropenem were determined by broth microdilution method. Isolates were screened for production of Extended Spectrum Beta-Lactamase (ESBL. Multiplex PCR was performed for the detection of Amp C genes after phenotypic testing (Hodge test and inhibitor based test. Results : Cefoxitin Hodge test was positive in 40 isolates which included 20 E. coli and 20 K. pneumoniae. There was zone enhancement with boronic acid in 55 isolates, of which 36 were K. pneumoniae and 19 were E. coli. Multiplex PCR detected Amp C in 11/25 E. coli and 12/52 K. pneumoniae isolates. The Amp C genes detected were CIT (Amp C origin - Citrobacter freundii, DHA (Dhahran Hospital, Saudi Arabia, ACC (Ambler class C, EBC (Amp C origin - Enterobacter cloacae groups. ESBL was co-produced in 54 isolates. Conclusions : Amp C was detected in 29.87% of the study isolates. Majority of them co-produced ESBL. The most common Amp C was the CIT family. Screen tests for cefoxitin resistance may be falsely positive due to production of carbapenamases.

  19. Die Wirkung von Desacetylcefotaxin, einem Metaboliten von Cefotaxim, in vitro und auf die experimentelle Infektion mit Escherichia coli

    OpenAIRE

    Wirbelauer, J.; Hof, H.; Hacker, Jörg

    2009-01-01

    Die MHK-Werte von Desacetylcefotaxim gegen verschiedene, z. T. ampicillinresistente Stämme von Escherichia coH, die mit Hilfe einer Agardilutionsmethode erhoben wurden, waren höher als die von Cefotaxim und Ceftriaxon, jedoch niedriger als die von Cefoxitin. In einem Modell der systemischen Infektion der Maus mit einem plasmidtragenden, betalactamaseproduzierenden Stamm von E. coli führte die Therapie mit Desacetylcefotaxim zu einer starken Reduktion der Keime pro Leber. Im Vergleich zur Ther...

  20. Antimicrobial resistance of fecal Salmonella spp. isolated from all phases of pig production in 20 herds in Alberta and Saskatchewan

    OpenAIRE

    Rosengren, Leigh B.; Waldner, Cheryl L.; Reid‐Smith, Richard J.; Checkley, Sylvia L.; McFall, Margaret E.; Rajíc, Andrijana

    2008-01-01

    Salmonella spp. (n = 468), isolated from the feces of sows, nursery, and grow‐finish pigs in 20 farrow‐to‐finish herds in Alberta and Saskatchewan, were tested for susceptibility to 16 antimicrobials. No resistance was identified to amikacin, amoxicillin‐clavulanic acid, ceftiofur, ceftriaxone, ciprofloxacin or nalidixic acid, and less than 1% of the isolates were resistant to cefoxitin and gentamicin. Isolates were most commonly resistant to tetracycline (35%) and sulfamethoxazole (27%). Ove...

  1. beta-Lactamases and beta-lactam resistance in Escherichia coli.

    OpenAIRE

    Jacoby, G A; Sutton, L

    1985-01-01

    Escherichia coli strains determining 17 different plasmid-determined beta-lactamases were tested for resistance to new broad-spectrum beta-lactam antibiotics. Several beta-lactamases demonstrated enhanced resistance to cefamandole but only low-level resistance to other agents. High production of cloned E. coli chromosomal beta-lactamase, however, provided resistance to cefamandole, cefoxitin, cefotaxime, ceftazidime, and aztreonam but not to BMY-28142 or imipenem.

  2. ANTIMICROBIAL TREATMENT OF OBSTETRIC AND GYNECOLOGIC INFECTIONS

    Directory of Open Access Journals (Sweden)

    Srdjan Pesic

    2008-10-01

    Full Text Available Treatment regimens for pelvic inflammatory diseases (PID, as a common cause of morbidity in women under the age of 45, should provide broad-spectrum coverage of likely etiologic pathogens and take into account the polymicrobial nature of PID. Antibiotic regimens that do provide coverage of these pathogens showed unacceptably high failure rates. The most recent edition of the Center for Disease Control and Prevention of Sexually Transmitted Disease Treatment guidelines provides an evidence-based and reliable set of recommendations for treating patients with PID and other sexually transmitted diseases.Outpatient regimens for the treatment of mildly and moderately severe acute PID include ofloxacin or levofloxacin with or without metronidazole for anaerobic coverage for 14 days. Alternatively, a single dose ceftriaxone or cefoxitin plus probenecid, followed by doxycycline with or with metronidazole for 14 days. In more severe cases, inpatient antibiotic treatment should be based on intravenous therapy with cefotetan or cefoxitin plus doxycycline which should be continued until 24 hours after clinical improvement and followed by oral therapy with doxycycline and metronidazole. Clindamycin plus gentamicin can be used alternatively in penicillin-allergic and pregnant women.Many antimicrobial regimens effectively treat uncomplicated gonorrhea, like single-dose ceftriaxone or cefoxitin or other pareneral third-generation cephalosporin. Treatment options for uncomplicated genitourinary chlamydial infection include a single dose azithromycin orally or doxycycline for seven days. A first-line drug for chlamydial infection in pregnant women is erythromycin base or amoxicillin.

  3. Comparison of phenotypic and molecular methods in the detection of methicillin resistant Staphylococcus aureus and its implications

    Directory of Open Access Journals (Sweden)

    Poongodi Lakshmi Santhanakumarasamy

    2015-01-01

    Full Text Available Background: Globally, Staphylococcus aureus is considered the most common cause of nosocomial infections. In recent times, there is a steady rise in the number of methicillin resistant S. aureus (MRSA isolates. Aim: This study was done to find out the prevalence, antimicrobial sensitivity pattern and evaluation of different methods (cefoxitin disc diffusion [DD] method, Chrom agar and polymerase chain reaction [PCR] in the detection of MRSA. Materials and Methods: A total of 100 S. aureus isolates from pus samples were identified by standard biochemical techniques. Antimicrobial susceptibility testing was done by Kirby Bauer′s DD method as per Clinical and Laboratory Standards Institute guidelines. D test was done to detect clindamycin resistance. Methicillin resistance was evaluated by cefoxitin DD method, Chrom agar (HiCrome MeReSa agar base and selective supplement and reverse transcription-PCR. Result: Out of 100 S. aureus isolates, 34% were detected as MRSA by cefoxitin DD method. All these isolates were detected by Chrom agar within 24 h. Additional isolates were not detected even after 48 h of incubation. mecA gene was detected by PCR in all these 34 MRSA isolates. Conclusion: The early detection of MRSA is of prime importance in the prognosis of staphylococcal infections. An integrated awareness program, good hand wash technique, epidemiological studies and effective control measures are the goals for elimination of MRSA in hospitals.

  4. Detection of Methicillin Resistant Staphylococcus aureus and Determination of Minimum Inhibitory Concentration of Vancomycin for Staphylococcus aureus Isolated from Pus/Wound Swab Samples of the Patients Attending a Tertiary Care Hospital in Kathmandu, Nepal

    Directory of Open Access Journals (Sweden)

    Raghabendra Adhikari

    2017-01-01

    Full Text Available The present study was conducted to evaluate the performance of cefoxitin disc diffusion method and oxacillin broth microdilution method for detection of methicillin resistant S. aureus (MRSA, taking presence of mecA gene as reference. In addition, inducible clindamycin resistance and beta-lactamase production were studied and minimum inhibitory concentration (MIC of vancomycin for S. aureus isolates was determined. A total of 711 nonrepeated pus/wound swab samples from different anatomic locations were included in the study. The Staphylococcus aureus was identified on the basis of colony morphology, Gram’s stain, and biochemical tests. A total of 110 (15.47% S. aureus isolates were recovered, of which 39 (35.50% isolates were identified as MRSA by cefoxitin disc diffusion method. By oxacillin broth microdilution method, 31.82% of the Staphylococcus aureus isolates were found to be MRSA. However, mecA gene was present in only 29.1% of the isolates. Further, beta-lactamase production was observed in 71.82% of the isolates, while inducible clindamycin resistance was found in 10% of S. aureus isolates. The MIC value of vancomycin for S. aureus ranged from 0.016 μg/mL to 1 μg/mL. On the basis of the absolute sensitivity (100%, both phenotypic methods could be employed for routine diagnosis of MRSA in clinical microbiology laboratory; however cefoxitin disc diffusion could be preferred over MIC method considering time and labour factor.

  5. Phenotypic and molecular characteristics of methicillin-resistant Staphylococcus aureus isolates from Ekiti State, Nigeria

    Directory of Open Access Journals (Sweden)

    Olowe OA

    2013-08-01

    Full Text Available Olugbenga Adekunle Olowe,1 Olayinka Oluwatoyin Kukoyi,2 Samuel Sunday Taiwo,1 Olusola Ojurongbe,1 Oluyinka Oladele Opaleye,1 Oloyede Samuel Bolaji,1 Abiodun Adebimpe Adegoke,1 Olufunmilola Bamidele Makanjuola,1 David Olusoga Ogbolu,3 Oyebode Terry Alli31Department of Medical Microbiology and Parasitology, College of Health Sciences, Ladoke Akintola University of Technology, Ogbomoso, Nigeria; 2Department of Microbiology, College of Sciences, Afe Babalola University, Ado-Ekiti, Nigeria; 3Department of Biomedical Sciences, College of Health Sciences, Lautech, Osogbo, NigeriaIntroduction: The characteristics and antimicrobial resistance profiles of Staphylococcus aureus differs according to geographical regions and in relation to antibiotic usage. The aim of this study was to determine the biochemical characteristics of the prevalent S. aureus from Ekiti State, Nigeria, and to evaluate three commonly used disk diffusion methods (cefoxitin, oxacillin, and methicillin for the detection of methicillin resistance in comparison with mecA gene detection by polymerase chain reaction.Materials and methods: A total of 208 isolates of S. aureus recovered from clinical specimens were included in this study. Standard microbiological procedures were employed in isolating the strains. Susceptibility of each isolate to methicillin (5 µg, oxacillin (1 µg, and cefoxitin (30 µg was carried out using the modified Kirby–Bauer/Clinical and Laboratory Standard Institute disk diffusion technique. They were also tested against panels of antibiotics including vancomycin. The conventional polymerase chain reaction method was used to detect the presence of the mecA gene.Results: Phenotypic resistance to methicillin, oxacillin, and cefoxitin were 32.7%, 40.3%, and 46.5%, respectively. The mecA gene was detected in 40 isolates, giving a methicillin-resistant S. aureus (MRSA prevalence of 19.2%. The S. aureus isolates were resistant to penicillin (82.7% and tetracycline

  6. Rapid antibiotic susceptibility phenotypic characterization of Staphylococcus aureus using automated microscopy of small numbers of cells.

    Science.gov (United States)

    Price, Connie S; Kon, Shelley E; Metzger, Steven

    2014-03-01

    Staphylococcus aureus remains a leading, virulent pathogen capable of expressing complex drug resistance that requires up to 2-4 days for laboratory analysis. In this study, we evaluate the ability of automated microscopy of immobilized live bacterial cells to differentiate susceptible from non-susceptible responses of S. aureus isolates (MRSA/MSSA, clindamycin resistance/susceptibility and VSSA/hVISA/VISA) to an antibiotic based on the characterization of as few as 10 growing clones after 4 h of growth, compared to overnight growth required for traditional culture based methods. Isolates included 131 characterized CDC isolates, 3 clinical isolates and reference strains. MRSA phenotype testing used 1 h of 1 μg/mL cefoxitin induction followed by 3 h of 6 μg/mL cefoxitin. Clindamycin susceptibility testing used 1h of induction by 0.1 μg/mL erythromycin followed by 3h of 0.5 μg/mL clindamycin. An automated microscopy system acquired time-lapse dark-field images, and then computed growth data for individual immobilized progenitor cells and their progeny clones while exposed to different test conditions. Results were compared to concurrent cefoxitin disk diffusion and D-test references. For CDC organisms, microscopy detected 77/77 MRSA phenotypes and 54/54 MSSA phenotypes, plus 53/56 clindamycin-resistant and 75/75 clindamycin susceptible strains. Automated microscopy was used to characterize heterogeneous and inducible resistance, and perform population analysis profiles. Microscopy-based hVISA population analysis profiles (PAPs) were included as an extended proof of concept, and successfully differentiated VSSA from hVISA and VISA phenotypes compared to plate-based PAP. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

  7. A randomized trial of the effects of antibiotic prophylaxis on epidural-related fever in labor.

    Science.gov (United States)

    Sharma, Shiv K; Rogers, Beverly B; Alexander, James M; McIntire, Donald D; Leveno, Kenneth J

    2014-03-01

    It has been suggested that the development of maternal fever during epidural analgesia could be due to intrapartum infection. We investigated whether antibiotic prophylaxis before epidural placement decreases the rate of epidural-related fever. In this double-blind, placebo-controlled trial, 400 healthy nulliparous women requesting epidural analgesia were randomly assigned to receive either cefoxitin 2 g or placebo immediately preceding initiation of epidural labor analgesia. Maternal tympanic temperature was measured hourly, and intrapartum fever was defined as a maternal temperature of ≥38°C. Neonates born to women with fever were evaluated for possible sepsis, and available placentas were evaluated for the presence of neutrophilic inflammation. The primary outcome was maternal fever during epidural analgesia. Thirty-eight percent of women in the cefoxitin group and 40% of women in the placebo group developed fever (P = 0.68). The risk difference (95% confidence interval) for fever ≥38°C during labor (antibiotic versus placebo) was -2.0% (-11.5 to 7.5), and for fever >39°C during labor was -1.5% (-4.7 to 1.7). Approximately half of each study group had placental neutrophilic inflammation, but administration of cefoxitin had no significant effect on any grade of neutrophilic inflammation. Fever developed significantly more often in the women with placental neutrophilic inflammation compared with those without such inflammation (73/158 vs 33/144, P labor epidural analgesia is associated with placental inflammation, but fever and placental inflammation were not reduced with antibiotic prophylaxis. This finding suggests that infection is unlikely to be the cause in its development.

  8. Resistance to Methicillin in Coagulase-negative Staphylococci and Its Detection

    Directory of Open Access Journals (Sweden)

    Milan Kolář

    2010-01-01

    Full Text Available Resistance of staphylococci to methicillin is important especially in the case of Staphylococcus aureus isolates. Its impact in veterinary medicine is not exactly specified in coagulase-negative staphylococci; however, these staphylococci may represent an important reservoir of resistance genes. The study aimed at detecting resistance to methicillin in coagulase-negative staphylococci from raw materials and foodstuffs of animal origin and assessing the tests frequently used to determine this resistance. Coagulase-negative staphylococci (198 isolates of 12 species were tested. Resistance to methicillin was determined by the disk diffusion method using oxacillin and cefoxitin disks, microdilution method, detection of PBP2a and the mecA gene. Of the tested isolates, 109 (55.1% were classified as resistant by the diffusion test with oxacillin, 32 isolates (16.2% by the test with cefoxitin and 50 isolates (25.3% on the basis of oxacillin minimum inhibitory concentration (MIC. No resistant isolates were incorrectly identified as susceptible when using the disk diffusion method with oxacillin (sensitivity of 100%. However, apart from 22 correctly classified resistant isolates, another 87 isolates were incorrectly identified as resistant as well (specificity of 50.6%. The test with cefoxitin showed the lowest (45.5% sensitivity in determination of resistant isolates. By contrast, this test was the most precise in classification of resistant isolates (specificity of 87.5%. When using the microdilution method, resistant strains were identified with the sensitivity and specificity of 68.2% and 80.1%, respectively. The results revealed substantial variability of methicillin-resistant isolates ranging from 16.2% to 55.1%, depending on the phenotyping methods and recommended interpretation criteria used. Therefore, it is advisable to reconsider the current interpretation criteria in the case of coagulasenegative staphylococci of animal origin (with the

  9. Genetic characterisation of antimicrobial resistance and virulence genes in Staphylococcus aureus isolated from commercial broiler chickens in the Durban metropolitan area, South Africa

    Directory of Open Access Journals (Sweden)

    Nelisiwe Mkize

    2017-05-01

    Full Text Available Antimicrobial resistance of Staphylococcus aureus in human and veterinary medicine is a serious worldwide problem. The aim of this study was to investigate the prevalence of S. aureus in commercial broiler chickens as well as to establish antimicrobial susceptibility and the distribution of genetic determinants conferring resistance and virulence. One hundred and ninety-four samples were aseptically collected from broiler chicken slaughterhouses and retail outlets around the Durban metropolitan area in South Africa. Microbiological and molecular methods were used to detect the presence of S. aureus as well as its resistance- and virulence-associated genes. Polymerase chain reaction (PCR was used to confirm the presence of S. aureus by amplifying the nuc gene. Approximately 54% of 194 samples were positive for S. aureus. The disc diffusion technique was used to investigate antimicrobial susceptibility profiles of the S. aureus isolates to a battery of 10 antimicrobial agents, namely ampicillin, chloramphenicol, gentamicin, erythromycin, cefoxitin, kanamycin, streptomycin, tetracycline, vancomycin and trimethoprim. The results demonstrated that S. aureus isolates of abattoir origin had a high level (79.4% of resistance to tetracycline, followed by ampicillin, vancomycin, cefoxitin, trimethoprim, erythromycin and streptomycin with resistance rates of 65.1%, 61.9%, 60.3%, 58.7%, 57.1% and 46.0%, respectively. Staphylococcus aureus isolates of retail origin exhibited higher antimicrobial resistance prevalence rates than those of abattoir origin. Tetracycline had the highest resistance rate (100%, followed by cefoxitin (91.7%, erythromycin (83.3%, streptomycin (83.3% and kanamycin (66.7%. All isolates were resistant to two or more antimicrobial agents. Out of the four virulence genes that were screened, only two were detected (coagulase and protein A; however, their prevalence rates were very low. All antimicrobial resistance genes screened were

  10. Study of methicillin resistant Staphylococcus aureus (MRSA) in Danish pigs at slaughter and in imported retail meat reveals a novel MRSA type in slaughter pigs

    DEFF Research Database (Denmark)

    Agersø, Yvonne; Hasman, Henrik; Cavaco, Lina M.

    2012-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA), especially CC398, have emerged in livestock worldwide. We investigated the occurrence of MRSA in pigs at slaughter and in retail meat. During 2009, nasal swabs (n=789) were taken from pigs at slaughter. Moreover, 866 meat samples [Danish: pork...... soya broth with 4mg/L cefoxitine and 75mg/L aztreonam) and selective plating on Brilliance Chromogenic MRSA agar. The presence of mecA was confirmed by PCR and the MRSA isolates were spa typed. Novel MRSA spa types were characterized by MLST, PFGE and SCCmec typing. Thirteen percent (101...

  11. Enterobacter Asburiae Pneumonia with Cavitation

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    Cha, Seung Woo; Heo, Jeong Nam; Park, Choong Ki [Dept. of Radiology, Hanyang University College of Medicine, Guri Hospital, Guri (Korea, Republic of); Choi, Yo Won; Jeon, Seok Chol [Dept. of Radiology, Hanyang University College of Medicine, Seoul Hospital, Seoul (Korea, Republic of)

    2013-03-15

    Enterobacter species have increasingly been identified as pathogens over the past several decades. These bacterial species have become more important because most are resistant to cephalothin and cefoxitin, and can produce extended-spectrum {beta}-lactamase. Enterobacter asburiae (E. asburiae) is a gram-negative rod of the family Enterobacteriaceae, named in 1986. Since then, there has been only one clinical report of E. asburiae pneumonia. We report a case of E. asburiae pneumonia with cavitation and compare it with the previous case.

  12. Enterobacter Asburiae Pneumonia with Cavitation

    International Nuclear Information System (INIS)

    Cha, Seung Woo; Heo, Jeong Nam; Park, Choong Ki; Choi, Yo Won; Jeon, Seok Chol

    2013-01-01

    Enterobacter species have increasingly been identified as pathogens over the past several decades. These bacterial species have become more important because most are resistant to cephalothin and cefoxitin, and can produce extended-spectrum β-lactamase. Enterobacter asburiae (E. asburiae) is a gram-negative rod of the family Enterobacteriaceae, named in 1986. Since then, there has been only one clinical report of E. asburiae pneumonia. We report a case of E. asburiae pneumonia with cavitation and compare it with the previous case.

  13. Detection of Oxacillin Resistance in Isolated from the Neonatal and Pediatric Units of a Brazilian Teaching Hospital

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    Valéria Cataneli Pereira

    2009-01-01

    Full Text Available Objective To determine, by phenotypic and genotypic methods, oxacillin susceptibility in Staphylococcus aureus strains isolated from pediatric and neonatal intensive care unit patients seen at the University Hospital of the Botucatu School of Medicine. Methods A total of 100 S. aureus strains isolated from the following materials were studied: 25 blood cultures, 21 secretions, 12 catheters, 3 cannulae and one chest drain from 62 patients in the neonatal unit, and 36 blood cultures, one pleural fluid sample and one peritoneal fluid sample from 38 patients in the pediatric unit. Resistance of the S. aureus isolates to oxacillin was evaluated by the disk diffusion method with oxacillin (1 μg and cefoxitin (30 μg, agar screening test using Mueller-Hinton agar supplemented with 6 μg/ml oxacillin and 4% NaCl, and detection of the mecA gene by PCR. In addition, the isolates were tested for β-lactamase production using disks impregnated with Nitrocefin and hyperproduction of β-lactamase using amoxicillin (20 μg and clavulanic acid (10 μg disks. Results Among the 100 S. aureus strains included in the study, 18.0% were resistant to oxacillin, with 16.1% MRSA being detected in the neonatal unit and 21.0% in the pediatric unit. The oxacillin (1 μg and cefoxitin (30 μg disk diffusion methods presented 94.4% and 100% sensitivity, respectively, and 98.8% specificity. The screening test showed 100% sensitivity and 98.8% specificity. All isolates produced β-lactamase and one of these strains was considered to be a hyperproducer. Conclusions The 30 μg cefoxitin disk diffusion method presented the best result when compared to the 1 μg oxacillin disk. The sensitivity of the agar screening test was similar to that of the cefoxitin disk diffusion method and higher than that of the oxacillin disk diffusion method. We observed variations in the percentage of oxacillin-resistant isolates during the study period, with a decline over the last years which might

  14. Detection of Oxacillin Resistance in Staphylococcus aureus Isolated from the Neonatal and Pediatric Units of a Brazilian Teaching Hospital

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    Valéria Cataneli Pereira

    2009-01-01

    Full Text Available Objective: To determine, by phenotypic and genotypic methods, oxacillin susceptibility in Staphylococcus aureus strains isolated from pediatric and neonatal intensive care unit patients seen at the University Hospital of the Botucatu School of Medicine.Methods: A total of 100 S. aureus strains isolated from the following materials were studied: 25 blood cultures, 21 secretions, 12 catheters, 3 cannulae and one chest drain from 62 patients in the neonatal unit, and 36 blood cultures, one pleural fluid sample and one peritoneal fluid sample from 38 patients in the pediatric unit. Resistance of the S. aureus isolates to oxacillin was evaluated by the disk diffusion method with oxacillin (1 μg and cefoxitin (30 μg, agar screening test using Mueller-Hinton agar supplemented with 6 μg/ml oxacillin and 4% NaCl, and detection of the mecA gene by PCR. In addition, the isolates were tested for β-lactamase production using disks impregnated with Nitrocefin and hyperproduction of β-lactamase using amoxicillin (20 μg and clavulanic acid (10 μg disks.Results: Among the 100 S. aureus strains included in the study, 18.0% were resistant to oxacillin, with 16.1% MRSA being detected in the neonatal unit and 21.0% in the pediatric unit. The oxacillin (1 μg and cefoxitin (30 μg disk diffusion methods presented 94.4% and 100% sensitivity, respectively, and 98.8% specificity. The screening test showed 100% sensitivity and 98.8% specificity. All isolates produced β-lactamase and one of these strains was considered to be a hyperproducer.Conclusions: The 30 μg cefoxitin disk diffusion method presented the best result when compared to the 1 μg oxacillin disk. The sensitivity of the agar screening test was similar to that of the cefoxitin disk diffusion method and higher than that of the oxacillin disk diffusion method. We observed variations in the percentage of oxacillin-resistant isolates during the study period, with a decline over the last years which

  15. Pregnancy - associated human listeriosis: Virulence and genotypic analysis of Listeria monocytogenes from clinical samples.

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    Soni, Dharmendra Kumar; Singh, Durg Vijai; Dubey, Suresh Kumar

    2015-09-01

    Listeria monocytogenes, a life-threatening pathogen, poses severe risk during pregnancy, may cause abortion, fetal death or neonatal morbidity in terms of septicemia and meningitis. The present study aimed at characterizing L. monocytogenes isolated from pregnant women based on serotyping, antibiotic susceptibility, virulence genes, in vivo pathogenicity test and ERIC- and REP-PCR fingerprint analyses. The results revealed that out of 3700 human clinical samples, a total of 30 (0.81%) isolates [12 (0.80%) from placental bit (1500), 18 (0.81%) from vaginal swab (2200)] were positive for L. monocytogenes. All the isolates belonged to serogroup 4b, and were + ve for virulence genes tested i.e. inlA, inlC, inlJ, plcA, prfA, actA, hlyA, and iap. Based on the mice inoculation tests, 20 isolates showed 100% and 4 isolates 60% relative virulence while 6 isolates were non-pathogenic. Moreover, 2 and 10 isolates were resistant to ciprofloxacin and cefoxitin, respectively, while the rest susceptible to other antibiotics used in this study. ERIC- and REP-PCR collectively depicted that the isolates from placental bit and vaginal swab had distinct PCR fingerprints except a few isolates with identical patterns. This study demonstrates prevalence of pathogenic strains mostly resistant to cefoxitin and/or ciprofloxacin. The results indicate the importance of isolating and characterizing the pathogen from human clinical samples as the pre-requisite for accurate epidemiological investigations.

  16. Multicenter study of antimicrobial susceptibility of anaerobic bacteria in Korea in 2012.

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    Lee, Yangsoon; Park, Yeon Joon; Kim, Mi Na; Uh, Young; Kim, Myung Sook; Lee, Kyungwon

    2015-09-01

    Periodic monitoring of regional or institutional resistance trends of clinically important anaerobic bacteria is recommended, because the resistance of anaerobic pathogens to antimicrobial drugs and inappropriate therapy are associated with poor clinical outcomes. There has been no multicenter study of clinical anaerobic isolates in Korea. We aimed to determine the antimicrobial resistance patterns of clinically important anaerobes at multiple centers in Korea. A total of 268 non-duplicated clinical isolates of anaerobic bacteria were collected from four large medical centers in Korea in 2012. Antimicrobial susceptibility was tested by the agar dilution method according to the CLSI guidelines. The following antimicrobials were tested: piperacillin, piperacillin-tazobactam, cefoxitin, cefotetan, imipenem, meropenem, clindamycin, moxifloxacin, chloramphenicol, metronidazole, and tigecycline. Organisms of the Bacteroides fragilis group were highly susceptible to piperacillin-tazobactam, imipenem, and meropenem, as their resistance rates to these three antimicrobials were lower than 6%. For B. fragilis group isolates and anaerobic gram-positive cocci, the resistance rates to moxifloxacin were 12-25% and 11-13%, respectively. Among B. fragilis group organisms, the resistance rates to tigecycline were 16-17%. Two isolates of Finegoldia magna were non-susceptible to chloramphenicol (minimum inhibitory concentrations of 16-32 mg/L). Resistance patterns were different among the different hospitals. Piperacillin-tazobactam, cefoxitin, and carbapemems are highly active beta-lactam agents against most of the anaerobes. The resistance rates to moxifloxacin and tigecycline are slightly higher than those in the previous study.

  17. A combination of ceftaroline and daptomycin has synergistic and bactericidal activity in vitro against daptomycin nonsusceptible methicillin-resistant Staphylococcus aureus (MRSA).

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    Shafiq, Iffat; Bulman, Zackery P; Spitznogle, Sarah L; Osorio, Justin E; Reilly, Irene S; Lesse, Alan J; Parameswaran, Ganapathi I; Mergenhagen, Kari A; Tsuji, Brian T

    2017-05-01

    There is an urgent need to optimize therapeutic options in patients with methicillin-resistant Staphylococcus aureus (MRSA) bacteremia who have failed conventional therapy. Two clinical isolates were obtained from a 68-year-old male with persistent MRSA bacteremia before and after the development of daptomycin nonsusceptibility. The pharmacodynamic activity of monotherapies and combinations of ceftaroline, daptomycin, cefoxitin, nafcillin and vancomycin were evaluated in time-kill experiments versus 10 8 CFU/mL of the pre- and post-daptomycin nonsusceptible MRSA isolates. Cefoxitin, nafcillin and vancomycin alone or in combination with ceftaroline failed to generate prolonged bactericidal activity against the post-daptomycin nonsusceptible isolate whereas a ceftaroline-daptomycin combination resulted in 6, 24 and 48 h log 10 (CFU/mL) reductions of 3.90, 4.40 and 6.32. Population analysis profiles revealed a daptomycin heteroresistant subpopulation of the pre-daptomycin nonsusceptible MRSA isolate that expanded by >10,000× on daptomycin agar containing 2-16 mg/L in the post-daptomycin nonsusceptible isolate. Daptomycin and ceftaroline combinations may be promising against persistent MRSA bacteremia.

  18. Laboratory evaluation of phenotypic detection methods of methicillin-resistant Staphylococcus aureus.

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    Kali, Arunava; Stephen, Selvaraj; Umadevi, Sivaraman

    2014-01-01

    Although conventional antibiotic susceptibility tests are most commonly performed for methicillin-resistant Staphylococcus aureus (MRSA), the results of these phenotypic tests are dependent on the standardization of the culture conditions. The aim of the study was to evaluate the conventional phenotypic screening tests in comparison to the mecA gene polymerase chain reaction (PCR). One hundred and two clinical isolates of MRSA identified by the oxacillin disk diffusion were subjected to PCR for the mecA gene and by the cefoxitin disk diffusion test and culture on oxacillin screen agar, mannitol salt agar, and methicillin-resistant Staphylococcus aureus Agar (MeReSA) selective medium, for MRSA. Although all 102 isolates were resistant in oxacillin and cefoxitin disk diffusion, 92 (90.1%) isolates were positive for the mecA gene. The sensitivities of the mannitol salt agar, MeReSA agar, and oxacillin screen agar were 89.13, 97.82, and 98.91%, respectively. The oxacillin screen agar may be recommended for confirming methicillin resistance in the disk diffusion test in resource-poor settings, where molecular methods are not available.

  19. Antimicrobial resistance in coagulase-negative staphylococci from Nigerian traditional fermented foods.

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    Fowoyo, P T; Ogunbanwo, S T

    2017-01-31

    Coagulase-negative staphylococci have become increasingly recognized as the etiological agent of some infections. A significant characteristic of coagulase-negative staphylococci especially strains isolated from animals and clinical samples is their resistance to routinely used antibiotics although, resistant strains isolated from fermented foods have not been fully reported. A total of two hundred and fifty-five CoNS isolates were subjected to antimicrobial susceptibility test using the disc diffusion technique. The minimum inhibitory concentration of the isolates to the tested antibiotics was determined using the microbroth dilution method. Methicillin resistant strains were confirmed by detection of methicillin resistant genes (mecA) and also employing cefoxitin screening test. The isolates were confirmed to be methicillin resistant by the detection of mecA genes and the cefoxitin screening test. The isolates demonstrated appreciable resistance to ampicillin (86.7%), sulfomethoxazole-trimethoprim (74.9%), amoxicillin-clavulanic acid (52.5%) and oxacillin (35.7%). Methicillin resistance was exhibited by 13 out of the 255 isolates although no mecA gene was detected. It was also observed that the methicillin resistant isolates were prevalent in these traditional foods; iru, kindirmo, nono and wara. This study has ameliorated the incidence of multiple antibiotic resistant coagulase-negative staphylococci in Nigerian fermented foods and if not tackled adequately might lead to horizontal transfer of antibiotic resistance from food to man.

  20. Evaluation of reference values for phenotypic tests to detect oxacillin resistance in coagulase-negative staphylococci.

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    Pinheiro, Luiza; Mello, Priscila L; Abraão, Ligia M; Corrente, José Eduardo; Lourdes Rs Cunha, Maria de

    2018-03-09

    To evaluate the adequacy of the disc-diffusion test and E-test ® compared with detection of mecA for coagulase-negative staphylococci isolated from blood cultures, nasal swabs and wounds. Agreement between all techniques was observed in 65.7% of cases. The greatest discrepancy between mecA/susceptible E-test was observed for non-epidermidis species. A resistance breakpoint ≤19 mm using the oxacillin disc was found to best classify all coagulase-negative staphylococci isolates; Staphylococcus epidermidis, ≤19 mm (oxacillin) and ≤27 mm (cefoxitin); Staphylococcus haemolyticus and Staphylococcus capitis, ≤21 mm (oxacillin) and ≤18 mm (cefoxitin); Staphylococcus warneri, MICs ≥0.75 mg/l. Although no longer recommended by the Clinical Laboratory Standards Institute, we observed some cases in which only the oxacillin disc-diffusion test detected resistance. The discrepancy between phenotypic tests and mecA is probably due to heterogeneity and borderline resistance.

  1. Laboratory evaluation of phenotypic detection methods of methicillin-resistant Staphylococcus aureus

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    Arunava Kali

    2014-12-01

    Full Text Available Although conventional antibiotic susceptibility tests are most commonly performed for methicillin-resistant Staphylococcus aureus (MRSA, the results of these phenotypic tests are dependent on the standardization of the culture conditions. The aim of the study was to evaluate the conventional phenotypic screening tests in comparison to the mecA gene polymerase chain reaction (PCR. One hundred and two clinical isolates of MRSA identified by the oxacillin disk diffusion were subjected to PCR for the mecA gene and by the cefoxitin disk diffusion test and culture on oxacillin screen agar, mannitol salt agar, and methicillin-resistant Staphylococcus aureus Agar (MeReSA selective medium, for MRSA. Although all 102 isolates were resistant in oxacillin and cefoxitin disk diffusion, 92 (90.1% isolates were positive for the mecA gene. The sensitivities of the mannitol salt agar, MeReSA agar, and oxacillin screen agar were 89.13, 97.82, and 98.91%, respectively. The oxacillin screen agar may be recommended for confirming methicillin resistance in the disk diffusion test in resource-poor settings, where molecular methods are not available.

  2. Six-Year Retrospective Review of Hospital Data on Antimicrobial Resistance Profile of Staphylococcus aureus Isolated from Skin Infections from a Single Institution in Greece

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    Christina Stefanaki

    2017-12-01

    Full Text Available Objective: To determine the prevalence of resistant strains of Staphylococcus aureus (S. aureus isolated from Skin and soft tissue infections (SSTI to various antibiotics. Material and Methods: All culture-positive results for S. aureus from swabs taken from patients presenting at one Greek hospital with a skin infection between the years 2010–2015 were examined retrospectively. Bacterial cultures, identification of S. aureus and antimicrobial susceptibility testing were performed using the disk diffusion method according to Clinical and Laboratory Standards Institute (CLSI guidelines and European Committee on Antimicrobial testing (EUCAST breakpoints. EUCAST breakpoints were applied if no CLSI were available. Results: Of 2069 S. aureus isolates identified, 1845 (88% were resistant to one or more antibiotics. The highest resistance was observed for benzylpenicillin (71.9%, followed by erythromycin (34.3%. Resistant strains to cefoxitin defined as MRSA (methicillin-resistant S. aureus represented 21% of total isolates. Interestingly, resistance to fusidic acid was 22.9% and to mupirocin as high as 12.7%. Low rates were observed for minocycline, rifampicin and trimethoprim/sulfamethoxazole (SXT. Resistance to antibiotics remained relatively stable throughout the six-year period, with the exception of cefoxitin, fusidic acid and SXT. A high percentage of MRSA strains were resistant to erythromycin (60%, fusidic acid (46%, clindamycin (38% and tetracycline (35.5%. Conclusions: Special attention is required in prescribing appropriate antibiotic therapeutic regimens, particularly for MRSA. These data on the susceptibility of S. aureus may be useful for guiding antibiotic treatment.

  3. Carriage frequency, phenotypic and genotypic characteristics of Staphylococcus aureus isolated from dialysis and kidney tranplant patients at a hosptial in northern Paraná

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    Luciana Borges Giarola

    2012-09-01

    Full Text Available The objective of the present study was to determine the frequency of Staphylococcus aureus nasal carriage among dialysis and kidney transplant patients, to identify the antimicrobial resistance profile of these strains and to verify their genetic profiles with the RW3A primer. The study included 159 individuals, comprising 111 dialysis and 48 kidney transplant patients. Of the 48 transplant patients, 75% were positive for S. aureus, whereas 49% of the 111 dialysis patients were carriers. Two samples yielded conflicting results for oxacillin sensitivity between the disk diffusion and minimum inhibitory concentration (MIC assays: both were sensitive by the disk diffusion assay and resistant by MIC (4 μg/ml. In the antibiogram by disk diffusion, ten samples were resistant to cefoxitin, among which eight were also resistant to oxacillin. The resistance of the ten samples to cefoxitin by the disk diffusion assay was confirmed by MIC. Of the ten oxacillin-resistant samples, eight harbored the mecA gene. All samples were sensitive to vancomycin, and most were resistant to penicillin and demonstrated high rates of resistance to the other antimicrobials tested. The samples from dialysis patients exhibited a more homogenous genetic profile. Among the samples with a high percent similarity, no correlation with sensitivity or resistance to oxacillin was observed. According to the results of this study, the implementation of prevention and control measures, such as increased restrictions on prescriptions for antimicrobial drugs and nasal decontamination prior to high-risk procedures, is recommended.

  4. Comparative Efficacy of Ceftaroline with Linezolid against Staphylococcus aureus and Methicillin Resistant Staphylococcus aureus.

    Science.gov (United States)

    Hafeez, Amira; Munir, Tehmina; Rehman, Sabahat; Najeeb, Sara; Gilani, Mehreen; Latif, Mahwish; Ansari, Maliha; Saad, Nadia

    2015-04-01

    To compare the in vitro antimicrobial efficacy of ceftaroline with linezolid against Staphylococcus aureus and methicillin resistant Staphylococcus aureus. Quasi-experimental study. Microbiology Department, Army Medical College, Rawalpindi, from January to December 2013. Clinical samples from respiratory tract, blood, pus and various catheter tips routinely received in the Department of Microbiology, Army Medical College, Rawalpindi were innoculated on blood and MacConkey agar. Staphylococcus aureus was identified by colony morphology, Gram reaction, catalase test and coagulase test. Methicillin resistant Staphylococcus aureus detection was done by modified Kirby Bauer disc diffusion method using cefoxitin disc (30 μg) and the isolates were considered methicillin resistant if the zone of inhibition around cefoxitin disc was ≤ 21 mm. Bacterial suspensions of 56 Staphylococcus aureus isolates and 50 MRSA isolates were prepared, which were standardized equal to 0.5 McFarland's turbidity standard and inoculated on Mueller-Hinton agar plates followed by application of ceftaroline and linezolid disc (Oxoid, UK), according to manufacturer's instructions. The plates were then incubated at 37 °C aerobically for 18 - 24 hours. Diameters of inhibition zone were measured and interpretated as per Clinical and Laboratory Standards Institute (CLSI) guidelines. Out of 106 isolates all of the 56 Staphylococcus aureus (100%) were sensitive to ceftaroline and linezolid. However, out of 50 methicillin resistant Staphylococcus aureus, 48 (96%) were sensitive to ceftaroline whereas, 49 (98%) were sensitive to linezolid. Ceftaroline is equally effective as linezolid against Staphylococcus aureus and methicillin resistant Staphylococcus aureus.

  5. In Vitro Synergistic Effect of Psidium guineense (Swartz in Combination with Antimicrobial Agents against Methicillin-Resistant Staphylococcus aureus Strains

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    Tiago Gomes Fernandes

    2012-01-01

    Full Text Available The aim of this study was to evaluate the antimicrobial activity of aqueous extract of Psidium guineense Swartz (Araçá-do-campo and five antimicrobials (ampicillin, amoxicillin/clavulanic acid, cefoxitin, ciprofloxacin, and meropenem against twelve strains of Staphylococcus aureus with a resistant phenotype previously determined by the disk diffusion method. Four S. aureus strains showed resistance to all antimicrobial agents tested and were selected for the study of the interaction between aqueous extract of P. guineense and antimicrobial agents, by the checkerboard method. The criteria used to evaluate the synergistic activity were defined by the fractional inhibitory concentration index (FICI. All S. aureus strains were susceptible to P. guineense as determined by the microdilution method. The combination of the P. guineense extract with the antimicrobial agents resulted in an eight-fold reduction in the MIC of these agents, which showed a FICI ranging from 0.125 to 0.5, suggesting a synergistic interaction against methicillin-resistant Staphylococcus aureus (MRSA strains. The combination of the aqueous extract of P. guineense with cefoxitin showed the lowest FICI values. This study demonstrated that the aqueous extract of P. guineense combined with beta lactamics antimicrobials, fluoroquinolones, and carbapenems, acts synergistically by inhibiting MRSA strains.

  6. Actividad “in vitro” de 10 antimicrobianos frente a bacterias anaerobias: Estudio multicéntrico, 1999-2002 “In vitro” activity of ten antimicrobial agents against anaerobic bacteria. A collaborative study, 1999-2002

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    M. Litterio

    2004-09-01

    Full Text Available Se evaluó la actividad de ampicilina, ampicilina-sulbactama, cefoxitina, ceftriaxona, imipenem, piperacilina, piperacilina-tazobactama, clindamicina, metronidazol y azitromicina frente a 166 cepas de bacterias anaerobias aisladas en 8 hospitales de Buenos Aires. Se estudiaron: Bacteroides grupo fragilis (65, Fusobacterium spp. (26, Prevotella spp. (21, Porphyromonas spp. (10, Clostridium difficile (10, otros clostridios (12 y cocos gram-positivos (22. Las CIMs se determinaron usando el método patrón de dilución en agar recomendado por el NCCLS, documento M11-A5. Los antibióticos más activos fueron metronidazol y piperacilina-tazobactama que exhibieron valores de CIM90£ 2 µg/ml y £ 4 µg/ml frente a los microorganismos gram-negativos y £ 2 µg/ml y £ 8 µg/ml frente a los microorganismos gram-positivos, respectivamente. Entre los b-lactámicos el orden de actividad frente a bacilos gram-negativos fue: imipenem > piperacilina > cefoxitina > ceftriaxona > ampicilina. En gram-positivos la actividad decreciente fue: piperacilina> imipenem > cefoxitina > ceftriaxona > ampicilina. La mayoría de las especies estudiadas mostraron distintos niveles de resistencia con clindamicina y azitromicina. Sin embargo, el 90% de las cepas de Fusobacterium nucleatum y Por-phyromonas spp. fue inhibido por una concentración de 0,125 µg/ml de clindamicina y azitromicina, respectivamente.The antimicrobial activity of ampicillin, ampicillin-sulbactam, cefoxitin, ceftriaxone, imipenem, piperacillin, piperacillin-tazobactam, clindamycin, metronidazole, and azitromycin was assesed against 166 strains of anaerobic bacteria recovered from eight hospitals in Buenos Aires. The strains studied were Bacteroidesfragilis group (65, Fusobacterium spp. (26, Prevotella spp. (21, Porphyromonas spp. (10, Clostridium difficile (10, other clostridia (12, and gram-positive cocci (22. The MICs were determined by the agar dilution method according to NCCLS document M11-A5

  7. [Identification of anaerobic gram-negative bacilli isolated from various clinical specimens and determination of antibiotic resistance profiles with E-test methods].

    Science.gov (United States)

    Demir, Cengiz; Keşli, Recep

    2018-01-01

    The aim of this study was to identify gram-negative anaerobic bacilli isolated from various clinical specimens that were obtained from patients with suspected anaerobic infections and to determine the antibiotic resistance profiles by using the antibiotic concentration gradient method. The study was performed in Afyon Kocatepe University Ahmet Necdet Sezer Research and Practice Hospital, Medical Microbiology Laboratory between 1 November 2014 and 30 October 2015. Two hundred and seventyeight clinical specimens accepted for anaerobic culture were enrolled in the study. All the samples were cultivated anaerobically by using Schaedler agar with 5% defibrinated sheep blood and Schaedler broth. The isolated anaerobic gram-negative bacilli were identified by using both the conventional methods and automated identification system (VITEK 2, bioMerieux, France). Antibiotic susceptibility tests were performed with antibiotic concentration gradient method (E-test, bioMerieux, France); against penicillin G, clindamycin, cefoxitin, metronidazole, moxifloxacin, imipenem, meropenem, ertapenem and doripenem for each isolate. Of the 28 isolated anaerobic gram-negative bacilli; 14 were identified as Bacteroides fragilis group, 9 were Prevotella spp., and 5 were Fusobacterium spp. The highest resistance rate was found against penicillin (78.5%) and resistance rates against clindamycin and cefoxitin were found as 17.8% and 21.4%, respectively. No resistance was found against metronidazole, moxifloxacin, imipenem, meropenem, ertapenem and doripenem. As a result, isolation and identification of anaerobic bacteria are difficult, time-consuming and more expensive when compared with the cost of aerobic culture. The rate of anaerobic bacteria isolation may be increased by obtaining the appropriate clinical specimen and appropriate transportation of these specimens. We believe that the data obtained from the study in our center may offer benefits for the follow up and treatment of infections

  8. Prevalence of the Panton-Valentine Leukocidin Gene in Clinical Isolates of Staphylococcus aureus Isolated From Hospitals the Ilam Province of Iran

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    Rostamzad

    2016-01-01

    Full Text Available Background Panton-Valentine leukocidin (luk-pv is a cytotoxin that causes leukocyte destruction and tissue necrosis. Objectives The aim of this study was to determine the prevalence of the pv1, femA, and mecA genes in staphylococcus aureus isolates from clinical specimens in hospitals in Ilam, Iran. Materials and Methods One hundred and sixty Staphylococcus aureus isolates were collected from hospitals in Ilam, Iran, and phenotypic and genotypic examinations for methicillin-resistant S. aureus (MRSA isolates were carried out. The antibiotic profiles of these isolates, and the minimal inhibitory concentration (MIC of MRSA isolates was determined using the agar dilution method with vancomycin, cefoxitin, and oxacillin. All isolates were examined using polymerase chain reaction (PCR primers for the femA, mecA, and Panton Valentine leukocidin (luk-pv genes. Results The results showed 91 isolates (56.88% were coagulase-positive, and 69 isolates (43.12% were coagulase-negative Staphylococcus aureus (CNSA. Out of 91 (56.88% coagulase-positive staphylococci, 32 isolates (35.16% were resistant to cefoxitin, and 30 isolates (32.96% were resistant to oxacillin, using disc diffusion method. PCR revealed the presence of the femA gene (510 bp band in all coagulase-positive isolates (100%, and the mecA gene (513 bp band was detected in 32 isolates (35.16%; out of 32 MRSA isolates, 13 isolates (40.62% were positive for presence of the luk-pv gene (433 bp band. Conclusions The cefoxitin disk diffusion method showed the best results when compared to oxacillin disk, similar to results from detecting the mecA gene in PCR as a golden test. Studies on MRSA that carry the luk-pv gene should continue to provide significant insight into the prevalence and epidemiology of these important resistant pathogens. Also, the rate of pvl gene-producing isolates showed to be relatively high, and it should be detected in all staphylococcal infections.

  9. Prevalence and genotypic relatedness of methicillin resistant Staphylococcus aureus in a tertiary care hospital

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    B A Fomda

    2014-01-01

    Full Text Available Background: Methicillin-resistant Staphylococcus aureus (MRSA is the most common multidrug-resistant pathogen causing nosocomial infections across the world. MRSA is not only associated with significant mortality and morbidity but also places a large economic strain on our health care system. MRSA isolates are also typically resistant to multiple, non-β-lactam antibiotics. We conducted a prospective study in a tertiary care hospital, to determine the prevalence of MRSA and to establish the clonal distribution of MRSA isolates recovered from various clinical specimens. Materials and Methods: Clinical samples were cultured and S. aureus was identified as per standard microbiological procedures. Susceptibility testing was done by agar disk diffusion and minimum inhibitory concentration (MIC method as recommended by CLSI. Methicillin resistance was detected by phenotypic methods namely, oxacillin disc diffusion (ODD, minimum inhibitory concentration (MIC of oxacillin, cefoxitin disk diffusion (CDD, and MIC of cefoxitin. Amplification of mecA gene by PCR was used as gold standard for detection of methicillin resistance. Pulsed field gel electrophoresis (PFGE typing was performed for MRSA isolates. Results: Out of 390 S. aureus isolates, 154 (39.48% isolates were MRSA and 236 (60.51% isolates were MSSA. Penicillin was the least effective antibacterial drug against the hospital associated S. aureus isolates with 85.64% resistance rate. All the isolates were susceptible to vancomycin. The MRSA showed a high level of resistance to all antimicrobials in general in comparison to the MSSA and the difference was statistically significant (P < 0.05. Multiplex PCR performed for all strains showed amplification of both the mecA and nucA genes in MRSA strains whereas MSSA strains showed amplification of only nucA gene. PFGE of these isolates showed 10 different patterns. Conclusion: Prevalence of MRSA in our hospital was 39.48%. Most of these isolates were

  10. Is there a need to revise the antibiotic concentration in Clinical and Laboratory Standards Institute-Recommended Oxacillin Screen Agar?

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    Niveditha Nagasundaram

    2017-01-01

    Full Text Available Introduction: In routine diagnostic microbiology laboratories, Clinical and Laboratory Standards Institute (CLSI recommends the use of cefoxitin disc, in addition to oxacillin screen agar (OSA of 6 μg/ml for the detection of methicillin-resistant Staphylococcus aureus (MRSA, whereas minimum inhibitory concentration values of oxacillin for S. aureus are ≤2 μg/ml (susceptible and ≥4 μg/ml (resistant. Hence, the study was carried out to evaluate the ability of screen agar with lower concentrations of oxacillin to identify the isolates of MRSA and to compare this with cefoxitin disc diffusion (CDD. Materials and Methods: Six hundred and seventy-six isolates of S. aureus were screened for methicillin resistance by OSA with 2 μg/ml and 4 μg/ml and 6 μg/ml of oxacillin concentration as well as CDD. Polymerase chain reaction for mecA gene was carried out for all isolates which grew on OSA 2, 4 and 6 μg/ml regardless of their cefoxitin susceptibility. Latex agglutination test for penicillin-binding protein 2a was performed for the isolates which grew on OSA 2 and or 4 μg/ml but not on OSA 6 μg/ml. Results: Eight per cent of MRSA isolates was missed by using OSA 6 μg/ml, when compared with other methods. Sensitivities of OSA 2 μg/ml, OSA 6 μg/ml and CDD were found to be 100%, 92.5% and 97.5%, respectively, and specificities for the same were found to be 100%, 100% and 98%, respectively. As per FDA criteria, categorical agreement for OSA 2 μg/ml was found to be 100% in comparison with the reference broth microdilution method. No major and very major discrepancies were documented. Conclusion: Similar findings on a larger and more heterogeneous collection of isolates may indicate the need to revise the concentration of OSA to 2 μg/ml for the detection of MRSA.

  11. Mycobacterium abscessus Endocarditis: A Case Report and Literature Review

    Directory of Open Access Journals (Sweden)

    Wei-Chung Tsai

    2008-09-01

    Full Text Available Infective endocarditis owing to Mycobacterium abscessus infection is rarely reported. Most cases of infective endocarditis caused by Mycobacterium abscessus are seen in patients after valve replacement. Although early surgical intervention is recommended and medical treatment with antibiotics according to the susceptibility to the pathogen, such as amikacin, imipenem, cefoxitin, quinolones and macrolides, are applied, the course of such endocarditis is usually subacute and often has fatal outcomes. The present case was a 29-year-old male patient who was an intravenous drug user who had recurrent endocarditis caused by Mycobacterium abscessus. Unusually, our reported case was infected on his native valve. However, we experienced recurrence despite antimicrobial therapy. For culture-negative endocarditis, physicians should consider the possibility of Mycobacterium abscessus infection and related treatment difficulties.

  12. Determination of in vitro susceptibility of Mycobacterium tuberculosis to cephalosporins by radiometric and conventional methods

    International Nuclear Information System (INIS)

    Heifets, L.B.; Iseman, M.D.; Cook, J.L.; Lindholm-Levy, P.J.; Drupa, I.

    1985-01-01

    Among eight cephalosporins and cephamycins tested in preliminary in vitro screening against Mycobacterium tuberculosis, the most promising for further study was found to be ceforanide, followed by ceftizoxime, cephapirin, and cefotaxime. Moxalactam, cefoxitin, cefamandole, and cephalothin were found to be not active enough against M. tuberculosis to be considered for further in vitro studies. The antibacterial activity of various ceforanide concentrations was investigated by three methods: (i) the dynamics of radiometric readings (growth index) in 7H12 broth; (ii) the number of CFU in the same medium; and (iii) the proportion method on 7H11 agar plates. There was a good correlation among the results obtained with these methods. The MIC for most strains ranged from 6.0 to 25.0 micrograms/ml. The BACTEC radiometric method is a reliable, rapid, and convenient method for preliminary screening and determination of the level of antibacterial activity of drugs not commonly used against M. tuberculosis

  13. Mycobacterium abscessus Complex Infections in Humans.

    Science.gov (United States)

    Lee, Meng-Rui; Sheng, Wang-Huei; Hung, Chien-Ching; Yu, Chong-Jen; Lee, Li-Na; Hsueh, Po-Ren

    2015-09-01

    Mycobacterium abscessus complex comprises a group of rapidly growing, multidrug-resistant, nontuberculous mycobacteria that are responsible for a wide spectrum of skin and soft tissue diseases, central nervous system infections, bacteremia, and ocular and other infections. M. abscessus complex is differentiated into 3 subspecies: M. abscessus subsp. abscessus, M. abscessus subsp. massiliense, and M. abscessus subsp. bolletii. The 2 major subspecies, M. abscessus subsp. abscessus and M. abscessus subsp. massiliense, have different erm(41) gene patterns. This gene provides intrinsic resistance to macrolides, so the different patterns lead to different treatment outcomes. M. abscessus complex outbreaks associated with cosmetic procedures and nosocomial transmissions are not uncommon. Clarithromycin, amikacin, and cefoxitin are the current antimicrobial drugs of choice for treatment. However, new treatment regimens are urgently needed, as are rapid and inexpensive identification methods and measures to contain nosocomial transmission and outbreaks.

  14. The Survey for AmpC beta-lactamase Production and Characterization of Antibiotic Resistance Profile in Clinical Isolates of Klebsiella oxytoca

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    Mahbobeh Nassari

    2016-05-01

    beta-lactamase producing. Among examined antimicrobials, imipenem (100% and colistin (100% were most effective drugs against isolates. Respectively, 88.6%, 88.6%, 85.7% and 85.7% isolates were resistant to amikacin, cefoxitin, ciprofloxacin and cefepime. Strains showed the most frequent resistance to ceftazidime (20%. All AmpC beta-lactamase positive isolates were sensitive to amikacin, imipenem and colistin. Conclusion: Results of current study showed third-gerneration cephalosprins are not effective against 20% of infections caused by Klebsiella oxytoca. Resistance to two major classes of antibiotics (aminoglycosides and beta-lactams was seen among studied strains and treatment of infections causing by this isolates are major problem in future.

  15. Plasmid-mediated mcr-1 in carbapenem-susceptible Escherichia coli ST156 causing a blood infection: an unnoticeable spread of colistin resistance in Brazil?

    Directory of Open Access Journals (Sweden)

    Flavia Rossi

    Full Text Available OBJECTIVE: We describe an IncX4 pHC891/16mcr plasmid carrying mcr-1 in a colistin-resistant and carbapenem-susceptible E. coli isolate (HC891/16, ST156, which caused a blood infection in a Brazilian patient with gallbladder adenocarcinoma. METHODS: Strain HC891/16 was subjected to whole genome sequencing using the MiSeq Platform (Illumina, Inc., USA. Assembly was performed using Mira and ABACAS. RESULTS: The isolates showed resistance only to ciprofloxacin, ampicillin and cefoxitin, and whole-genome sequencing revealed the presence of aac(6’Ib-cr and blaTEM1. CONCLUSION: Our findings warn of the possible silent dissemination of colistin resistance by carbapenem-susceptible mcr-1 producers, as colistin susceptibility is commonly tested only among carbapenem-resistant isolates.

  16. PERFIL DE SENSIBILIDADE MICROBIANA IN VITRO DE LINHAGENS PATOGÊNICAS DE Escherichia coli ISOLADAS DE CARNE BOVINA

    Directory of Open Access Journals (Sweden)

    Samira Pirola Santos Mantilla

    2012-06-01

    Full Text Available This study aimed to analyze the antimicrobial resistance of Escherichia coli strains (EPEC A, EPEC B, EPEC C, EIEC A e EIEC B isolated from bovine meat. The antimicrobial susceptibility test was evaluated using the technique described by the National Committee for Clinical Laboratory Standards. The strains were resistant to most antibiotics tested, and gentamicin showed the best efficiency, with 84.9% of the strains showing sensitivity. In addition, cefoxitin was the least effective antimicrobial agent, have a higher percentage of resistant strains. The multidrug resistance to antimicrobials is a finding of great importance to public health, as resistant pathogens may be conveyed to consumers by the ingestion of animal products, making difficult the treatment of bacterial infections and increasing the occurrence of bacteria resistant to antibiotics.

  17. Fabrication, characterization and in vitro profile based interaction with eukaryotic and prokaryotic cells of alginate-chitosan-silica biocomposite.

    Science.gov (United States)

    Balaure, Paul Catalin; Andronescu, Ecaterina; Grumezescu, Alexandru Mihai; Ficai, Anton; Huang, Keng-Shiang; Yang, Chih-Hui; Chifiriuc, Carmen Mariana; Lin, Yung-Sheng

    2013-01-30

    This work is focused on the fabrication of a new drug delivery system based on polyanionic matrix (e.g. sodium alginate), polycationic matrix (e.g. chitosan) and silica network. The FT-IR, SEM, DTA-TG, eukaryotic cell cycle and viability, and in vitro assay of the influence of the biocomposite on the efficacy of antibiotic drugs were investigated. The obtained results demonstrated the biocompatibility and the ability of the fabricated biocomposite to maintain or improve the efficacy of the following antibiotics: piperacillin-tazobactam, cefepime, piperacillin, imipenem, gentamicin, ceftazidime against Pseudomonas aeruginosa ATCC 27853 and cefazolin, cefaclor, cefuroxime, ceftriaxone, cefoxitin, trimethoprim/sulfamethoxazole against Escherichia coli ATCC 25922 reference strains. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Effectiveness of the antimicrobial removal device, BACTEC 16B medium, and thiol broth in neutralizing antibacterial activities of imipenem, norfloxacin, and related agents.

    Science.gov (United States)

    Weinberg, E; Shungu, D L; Gadebusch, H H

    1984-02-01

    The Antimicrobial Removal Device (ARD), BACTEC 16B medium, and Thiol broth were evaluated for their effectiveness in reducing the activity of imipenem (IPM), cefoxitin, moxalactam, and ceftazidime in blood samples. In addition, the capability of the ARD and Thiol broth to bind norfloxacin and the ARD to bind oxolinic and nalidixic acids in urine samples was investigated. At the highest concentrations of the drugs tested (32 micrograms/ml for the four beta-lactams and 256 micrograms/ml for the three quinolinecarboxylic acids), there was at least a 95% reduction in the in vitro activity of each of the antibacterial agents for treated versus untreated samples. Of the compounds tested in the ARD system, the organic acids were more completely removed than were the beta-lactams. The Thiol broth was more effective than the ARD and the BACTEC 16B medium in inactivating imipenem, but it had no effect on the antibacterial activity of norfloxacin.

  19. Determination of in vitro susceptibility of Mycobacterium tuberculosis to cephalosporins by radiometric and conventional methods

    Energy Technology Data Exchange (ETDEWEB)

    Heifets, L.B.; Iseman, M.D.; Cook, J.L.; Lindholm-Levy, P.J.; Drupa, I.

    1985-01-01

    Among eight cephalosporins and cephamycins tested in preliminary in vitro screening against Mycobacterium tuberculosis, the most promising for further study was found to be ceforanide, followed by ceftizoxime, cephapirin, and cefotaxime. Moxalactam, cefoxitin, cefamandole, and cephalothin were found to be not active enough against M. tuberculosis to be considered for further in vitro studies. The antibacterial activity of various ceforanide concentrations was investigated by three methods: (i) the dynamics of radiometric readings (growth index) in 7H12 broth; (ii) the number of CFU in the same medium; and (iii) the proportion method on 7H11 agar plates. There was a good correlation among the results obtained with these methods. The MIC for most strains ranged from 6.0 to 25.0 micrograms/ml. The BACTEC radiometric method is a reliable, rapid, and convenient method for preliminary screening and determination of the level of antibacterial activity of drugs not commonly used against M. tuberculosis.

  20. Antimicrobial Disk Susceptibility Testing of Leptospira spp. Using Leptospira Vanaporn Wuthiekanun (LVW) Agar.

    Science.gov (United States)

    Wuthiekanun, Vanaporn; Amornchai, Premjit; Langla, Sayan; White, Nicholas J; Day, Nicholas P J; Limmathurotsakul, Direk; Peacock, Sharon J

    2015-08-01

    Leptospira Vanaporn Wuthiekanun (LVW) agar was used to develop a disk diffusion assay for Leptospira spp. Ten pathogenic Leptospira isolates were tested, all of which were susceptible to 17 antimicrobial agents (amoxicillin/clavulanic acid, amoxicillin, azithromycin, cefoxitin, ceftazidime, ceftriaxone, chloramphenicol, ciprofloxacin, clindamycin, doripenem, doxycycline, gentamicin, linezolid, nitrofurantoin, penicillin, piperacillin/tazobactam, and tetracycline). All 10 isolates had no zone of growth inhibition for four antimicrobials (fosfomycin, nalidixic acid, rifampicin, and trimethoprim/sulfamethoxazole). Of the ten Leptospira, seven had a growth inhibition zone of ≤ 21 mm for aztreonam, the zone diameter susceptibility break point for Enterobacteriaceae. This assay could find utility as a simple screening method during the epidemiological surveillance of antimicrobial resistance in Leptospira spp. © The American Society of Tropical Medicine and Hygiene.

  1. Salmonella enterica isolated from wildlife at two Ohio rehabilitation centers.

    Science.gov (United States)

    Jijón, Steffani; Wetzel, Amy; LeJeune, Jeffrey

    2007-09-01

    Between May and September 2004, fecal samples from various wildlife species admitted to two rehabilitation centers in Ohio were cultured for Salmonella enterica and Escherichia coli O157:H7. Eight of 71 (11%) samples, including specimens from three opossums (Didelphis virginiana), two gray squirrels (Sciurus carolinensis), a woodchuck (Marmota monax), a Harris hawk (Parabuteo unicinctus), and a screech owl (Otus asio) tested positive for Salmonella serovars Braenderup, Senftenberg, Oranienburg, and Kentucky. The Salmonella Oranienburg isolates were indistinguishable by pulsed-field gel electrophoresis. Most isolates were susceptible to commonly used antibiotics; however, the Salmonella Kentucky isolate was resistant to multiple beta-lactam antibiotics (amoxicillin/clavulanic acid and ampicillin), cefoxitin, and ceftiofur, a third-generation cephalosporin. Escherichia coli O157:H7 was not isolated from any sample. Transmission of Salmonella from wildlife may occur between animals at rehabilitation centers.

  2. Accuracy of phenotypic methicillin susceptibility methods in the detection of Staphylococcus aureus isolates carrying different SCCmec types

    Directory of Open Access Journals (Sweden)

    Pricilla DM de Matos

    2010-11-01

    Full Text Available A total of 138 isolates, 118 methicillin-resistant Staphylococcus aureus (MRSA isolates (staphylococcal cassette chromosome type II, 20 isolates, type III, 39 isolates and type IV, 59 isolates and 20 methicillin-sensitive S. aureus isolates were evaluated by phenotypic methods: cefoxitin and oxacillin disk diffusion (DD, agar dilution (AD, latex agglutination (LA, oxacillin agar screening (OAS and chromogenic agar detection. All methods showed 100% specificity, but only the DD tests presented 100% sensitivity. The sensitivity of the other tests ranged from 82.2% (OAS-98.3% (AD. The LA test showed the second lowest sensitivity (86.4%. The DD test showed high accuracy in the detection of MRSA isolates, but there was low precision in the detection of type IV isolates by the other tests, indicating that the genotypic characteristics of the isolates should be considered.

  3. Accuracy of phenotypic methicillin susceptibility methods in the detection of Staphylococcus aureus isolates carrying different SCCmec types.

    Science.gov (United States)

    Matos, Pricilla D M de; Schuenck, Ricardo P; Cavalcante, Fernanda S; Caboclo, Roberta M F; Santos, Kátia Regina N dos

    2010-11-01

    A total of 138 isolates, 118 methicillin-resistant Staphylococcus aureus (MRSA) isolates (staphylococcal cassette chromosome type II, 20 isolates, type III, 39 isolates and type IV, 59 isolates) and 20 methicillin-sensitive S. aureus isolates were evaluated by phenotypic methods: cefoxitin and oxacillin disk diffusion (DD), agar dilution (AD), latex agglutination (LA), oxacillin agar screening (OAS) and chromogenic agar detection. All methods showed 100% specificity, but only the DD tests presented 100% sensitivity. The sensitivity of the other tests ranged from 82.2% (OAS)-98.3% (AD). The LA test showed the second lowest sensitivity (86.4%). The DD test showed high accuracy in the detection of MRSA isolates, but there was low precision in the detection of type IV isolates by the other tests, indicating that the genotypic characteristics of the isolates should be considered.

  4. Antibiotic susceptibility profile of Aeromonas spp. isolates from food in Abu Dhabi, United Arab Emirates.

    Science.gov (United States)

    Awan, Mohammad Bashir; Maqbool, Ahmed; Bari, Abdul; Krovacek, Karel

    2009-01-01

    A total of 57 Aeromonas isolates from food samples such as fresh and frozen chicken, game birds, pasteurized milk, baby food, bakery products, fruit and vegetables, fish, and water from Abu Dahbi, UAE were investigated for antibiotic susceptibility profile. Most strains were resistant to penicillins (ticarcillin, mezlocillin, oxacillin, piperacillin), sulfamethoxazole, trimethoprim and macrolides (erythromycin, vancomycin, clindamycin) but sensitive to tetracycline, chloramphenicol, nitrofurantoin, aminoglycosides (amikacin, gentamicin, tobramycin), cephalosporins (cefuroxime, ceftrioxone, cefazolin, cephalexin, cephalothin, cefoxitin, cefotaxime), quinolone (ciprofloxacin), colistin sulphate and SXT (trimethoprim-sulfamethoxazole). On the other hand, many antibiotics showed excellent inhibitory activity (>75% strains were sensitive to them) against all the strains tested. These include cefuroxime, ceftrioxone, ciprofloxacin, colistin, amikacin, gentamicin, tetracycline, chloramphenicol, nitrofurantoin, cefotaxime and tobramycin. In conclusion, the results show a detailed pattern of sensitivity of the various Aeromonas spp. isolates to a variety of antibiotics and provide useful information in the context of selective isolation and phenotypic identification of the aeromonads from food.

  5. Activity of cephalosporins against methicillin-susceptible and methicillin-resistant, coagulase-negative staphylococci: minimal effect of beta-lactamase.

    Science.gov (United States)

    John, J F; McNeill, W F

    1980-01-01

    Eight cephalosporins were tested for their activity against methicillin-susceptible and methicillin-resistant, coagulase-negative staphylococci and for their resistance to beta-lactamase from methicillin-resistant, coagulase-negative staphylococci. Susceptibility testing by the agar plate method was evaluated for the effect of inoculum size and duration of incubation. Methicillin-susceptible, coagulase-negative staphylococci were highly susceptible to the cephalosporins, with cephapirin and cepahlothin showing the greatest activity, followed by cefazolin and cefamandole. Methicillin-resistant, coagulase-negative staphylococci displayed nearly total cross-resistance to the cephalosporins. Resistance increased with increasing inoculum size. Beta-Lactamases produced by methicillin-resistant, coagulase-negative staphylococci had a minimal hydrolytic effect on cepahlothin, cephapirin, cefazolin, and cefamandole and no measurable effect on cefoxitin. There was no correlation between the anti-staphylococcal activity and resistance to beta-lactamases. PMID:6966906

  6. Disease: H01050 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available H01050 Tsukamurella infections Tsukamurellae species are aerobic gram-positive rod...eam infections. Infectious disease ... Tsukamurella paurometabola [GN:tpr] Tsukamurella tyrosinosolvens Tsukamurella pulmonis Tsukamurella inchonensis Tsukamurella strandjordae ... Amikacin [DG:DG00403] Minocycline [DG:DG00009] Imipenem [DG:DG01212] Ciprofloxacin [DG:DG00617] Cefotaxime [DG:DG00570] Tsukamurella spp. are resistant to cefoxitin, ampicillin, and amoxicillin/clavulanic acid. ... PMID:18810513 (description, env_factor) ... AUTHORS ... Bouza E, Perez-Parra A, Rosal M, Martin-Rabadan P, Rodriguez-Creixems M, Marin M ... TITLE ... Tsukamurella: a cause of catheter-related bloodstream infections. ... JOURNAL ... Eur J Clin Microbiol Infect Dis 28:203-10 (2009) DOI:10.1007/s10096-008-0607-2 ...

  7. Antimicrobial resistance among pathogenic bacteria from mink (Neovison vison) in Denmark

    DEFF Research Database (Denmark)

    Nikolaisen, Nanett Kvist; Lassen, Desireé Corvera Kløve; Chriél, Mariann

    2017-01-01

    in mink. Results: A total number of 308 Escherichia coli isolates, 41 Pseudomonas aeruginosa, 36 Streptococcus canis, 30 Streptococcus dysgalactiae, 55 Staphylococcus delphini, 9 Staphylococcus aureus, and 20 Staphylococcus schleiferi were included in this study. Among E. coli, resistance was observed...... and gentamicin. Among the Staphylococcus spp., the highest occurrence of resistance was found for tetracycline. Regarding the nine S. aureus, one isolate was resistant to cefoxitin indicating it was a methicillin-resistant Staphylococcus aureus. Both β-hemolytic Streptococcus species showed high levels...... more frequently among the hemolytic isolates than among the non-hemolytic ones. The highest frequency of resistance was found to ampicillin, 82.3% and 48.0% of the hemolytic of the non-hemolytic isolates, respectively. The majority of the P. aeruginosa isolates were only sensitive to ciprofloxacin...

  8. Hospital Epidemiology of Methicillin-Resistant Staphylococcus aureus in a Tertiary Care Hospital in Moshi, Tanzania, as Determined by Whole Genome Sequencing

    DEFF Research Database (Denmark)

    Kumburu, Happiness H.; Sonda, Tolbert; Leekitcharoenphon, Pimlapas

    2018-01-01

    Objective. To determine molecular epidemiology of methicillin-resistant S. aureus in Tanzania using whole genome sequencing. Methods. DNA from 33 Staphylococcus species was recovered from subcultured archived Staphylococcus isolates. Whole genome sequencing was performed on IlluminaMiseq using pa...... in Moshi are highly diverse and epidemiologically unrelated. Temporal phylogenetic analysis provided better resolution on transmission and introduction of MRSA and it may be important to include this in future routines....... paired-end 2x250 bp protocol. Raw sequence data were analyzed using online tools. Results. Full susceptibility to vancomycin and chloramphenicol was observed. Thirteen isolates (43.3%) resisted cefoxitin and other antimicrobials tested. Multilocus sequence typing revealed 13 different sequence types...

  9. [Application of anaerobic bacteria detection in oral and maxillofacial infection].

    Science.gov (United States)

    Bao, Zhen-ying; Lin, Qin; Meng, Yan-hong; He, Chun; Su, Jia-zeng; Peng, Xin

    2016-02-18

    To investigate the distribution and drug resistance of anaerobic bacteria in the patients with oral and maxillofacial infection. Aerobic and anaerobic bacteria cultures from 61 specimens of pus from the patients with oral and maxillofacial infection in the Department of Oral and Maxillofacial Surgery, Peking University School of Stomatology were identified. The culture type was evaluated by API 20A kit and drug resistance test was performed by Etest method. The clinical data and antibacterial agents for the treatment of the 61 cases were collected, and the final outcomes were recorded. The bacteria cultures were isolated from all the specimens, with aerobic bacteria only in 6 cases (9.8%), anaerobic bacteria only in 7 cases (11.5%), and both aerobic and anaerobic bacteria in 48 cases (78.7%). There were 55 infected cases (90.2%) with anaerobic bacteria, and 81 anaerobic bacteria stains were isolated. The highest bacteria isolation rate of Gram positive anaerobic bacteria could be found in Peptostreptococcus, Bifidobacterium and Pemphigus propionibacterium. No cefoxitin, amoxicillin/carat acid resistant strain was detected in the above three Gram positive anaerobic bacteria. The highest bacteria isolation rate of Gram negative anaerobic bacteria could be detected in Porphyromonas and Prevotella. No metronidazole, cefoxitin, amoxicillin/carat acid resistant strain was found in the two Gram negative anaerobic bacteria. In the study, 48 patients with oral and maxillofacial infection were treated according to the results of drug resistance testing, and the clinical cure rate was 81.3%. Mixed aerobic and anaerobic bacteria cultures are very common in most oral and maxillofacial infection patients. Anaerobic bacteria culture and drug resistance testing play an important role in clinical treatment.

  10. Synergy of β-Lactams with Vancomycin against Methicillin-Resistant Staphylococcus aureus: Correlation of Disk Diffusion and Checkerboard Methods.

    Science.gov (United States)

    Sy, Cheng Len; Huang, Tsi-Shu; Chen, Chii Shiang; Chen, Yao-Shen; Tsai, Hung-Chin; Wann, Shue-Renn; Wu, Kuan-Sheng; Chen, Jui-Kuang; Lee, Susan Shin-Jung; Liu, Yung-Ching

    2016-03-01

    Modified disk diffusion (MDD) and checkerboard tests were employed to assess the synergy of combinations of vancomycin and β-lactam antibiotics for 59 clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and Mu50 (ATCC 700699). Bacterial inocula equivalent to 0.5 and 2.0 McFarland standard were inoculated on agar plates containing 0, 0.5, 1, and 2 μg/ml of vancomycin. Oxacillin-, cefazolin-, and cefoxitin-impregnated disks were applied to the surface, and the zones of inhibition were measured at 24 h. The CLSI-recommended checkerboard method was used as a reference to detect synergy. The MICs for vancomycin were determined using the Etest method, broth microdilution, and the Vitek 2 automated system. Synergy was observed with the checkerboard method in 51% to 60% of the isolates when vancomycin was combined with any β-lactam. The fractional inhibitory concentration indices were significantly lower in MRSA isolates with higher vancomycin MIC combinations (P synergy in MRSA isolates with bacterial inocula equivalent to McFarland standard 0.5 were 33.0% and 62.5% for oxacillin, 45.1% and 52.4% for cefazolin, and 43.1% and 52.4% for cefoxitin when combined with 0.5 and 2 μg/ml of vancomycin, respectively. Based on our study, the simple MDD method is not recommended as a replacement for the checkerboard method to detect synergy. However, it may serve as an initial screening method for the detection of potential synergy when it is not feasible to perform other labor-intensive synergy tests. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  11. Isolation and characterization of Enterobacteriaceae species infesting post-harvest strawberries and their biological control using bacteriophages.

    Science.gov (United States)

    Kurtböke, D Ipek; Palk, A; Marker, A; Neuman, C; Moss, L; Streeter, K; Katouli, M

    2016-10-01

    Strawberry is a significantly consumed fruit worldwide, mostly without being subjected to disinfection processes. During the harvest and transfer from farm to consumers as well as where organic farming practises have been employed, the surface of the fruit may become contaminated by pathogenic bacteria. Post-harvest strawberry fruits in punnets available for public consumption were thus screened for the presence of enteric bacteria in the Sunshine Coast region of Queensland, Australia. Some of the tested samples (13 %) were found to carry such bacteria and even in greater numbers if organic amendments were used (69 %). The bacteria were found to belong in the genera of Escherichia, Enterobacter, Raoultella, Klebsiella, Pantoea, Shigella, Citrobacter and Cronobacter within the family Enterobacteriaceae. Some of the isolates were found to adhere to Caco-2 cells representing human gut epithelium as well as carrying virulence and toxin genes. Resistance mostly against sulphafurazole, cefoxitin, ampicillin and nitrofurantoin was found among 14 different antimicrobial agents tested including 100 % resistance to cefoxitin and ampicillin in the genus Pantoea. In the second phase of the study, bacteriophages were isolated against the isolates and were subsequently applied to post-harvest fruits. A significant (P ≤ 0.001) reduction in the number of enteric bacteria was observed when a high-titre polyvalent bacteriophage suspension (×10(12) PFU/mL) was applied to the fruit surface. Bacteriophages also decreased the adhesion of the Escherichia coli isolates to Caco-2 cells. Findings might indicate that biological control using bacteriophages might be of significant value for the industry targeting to reduce pathogenic loads of bacteria on the fruit.

  12. Investigating antibacterial activity of Satureja bachtiarica against coagulasenegative staphylococcus strains isolated from hospitalized patients in ICU,Tehran-Iran

    Directory of Open Access Journals (Sweden)

    Niloofar Shadalooei

    2016-09-01

    Full Text Available Given the inappropriate use of antibiotics and prevalence of resistant bacteria, there is urgent need for antibacterial drugs that have fewer side effects than antibiotics. Satureja bachtiarica is a medicinal plant which had many uses in traditional medicine. In this research, the ethanol extract of leave of Satureja bachtiarica is tested on coagulase-negative staphylococcus strains. Materials and Methods: In this experimental study, after collecting and drying the plant extract, the ethanolic extract of the plant was extracted by soxhelet method. Then, the antibiotic resistance pattern of coagulase-negative staphylococcus strains to Cefoxitin, Tobramycin, Kanamycin, Amikacin, Gentamicin, was assessed. To evaluate the antibacterial activity, the minimum inhibitory concentration was assessed by using micro dilution broth method.The results of this study showed that the antimicrobial effect of Satureja extract is concentration dependent. The results of the antimicrobial activity of extracts, indicate that alcoholic extract in all dilutions have an antimicrobial effect on the coagulase-negative staphylococcus strains. The results show that coagulase-negative staphylococcus strains have highest resistance against Cefoxitin (0.39 mg/ml and highest sensitivity to Amikacin (0.035 μl/ml. However, in 200 and 100 mg/ml concentrations the extract has higher antibacterial effect. According to the results of this study, ethanol extracts of leave of Satureja bachtiarica had growth inhibitory effect on coagulase-negative staphylococcus strains. Therefore this plant has the potential to be evaluated as an alternative or adjunct to antibiotics to treat coagulase-negative staphylococcus infections.

  13. Antibiotic-resistant fecal bacteria, antibiotics, and mercury in surface waters of Oakland County, Michigan, 2005-2006

    Science.gov (United States)

    Fogarty, Lisa R.; Duris, Joseph W.; Crowley, Suzanne L.; Hardigan, Nicole

    2007-01-01

    Water samples collected from 20 stream sites in Oakland and Macomb Counties, Mich., were analyzed to learn more about the occurrence of cephalosporin-resistant Escherichia coli (E. coli) and vancomycin-resistant enterococci (VRE) and the co-occurrence of antibiotics and mercury in area streams. Fecal indicator bacteria concentrations exceeded the Michigan recreational water-quality standard of 300 E. coli colony forming units (CFU) per 100 milliliters of water in 19 of 35 stream-water samples collected in Oakland County. A gene commonly associated with enterococci from humans was detected in samples from Paint Creek at Rochester and Evans Ditch at Southfield, indicating that human fecal waste is a possible source of fecal contamination at these sites. E. coli resistant to the cephalosporin antibiotics (cefoxitin and/ or ceftriaxone) were found at all sites on at least one occasion. The highest percentages of E. coli isolates resistant to cefoxitin and ceftriaxone were 71 percent (Clinton River at Auburn Hills) and 19 percent (Sashabaw Creek near Drayton Plains), respectively. Cephalosporin-resistant E. coli was detected more frequently in samples from intensively urbanized or industrialized areas than in samples from less urbanized areas. VRE were not detected in any sample collected in this study. Multiple antibiotics (azithromycin, erythromycin, ofloxacin, sulfamethoxazole, and trimethoprim) were detected in water samples from the Clinton River at Auburn Hills, and tylosin (an antibiotic used in veterinary medicine and livestock production that belongs to the macrolide group, along with erythromycin) was detected in one water sample from Paint Creek at Rochester. Concentrations of total mercury were as high as 19.8 nanograms per liter (Evans Ditch at Southfield). There was no relation among percentage of antibiotic-resistant bacteria and measured concentrations of antibiotics or mercury in the water. Genetic elements capable of exchanging multiple antibiotic

  14. Colonisation of antibiotic resistant bacteria in a cohort of HIV infected children in Ghana.

    Science.gov (United States)

    Sampane-Donkor, Eric; Badoe, Ebenezer Vincent; Annan, Jennifer Adoley; Nii-Trebi, Nicholas

    2017-01-01

    Antibiotic use not only selects for resistance in pathogenic bacteria, but also in commensal flora of exposed individuals. Little is known epidemiologically about antibiotic resistance in relation to people with HIV infection in sub-Saharan Africa. This study investigated the carriage of antibiotic resistant bacteria among HIV infected children at a tertiary hospital in Ghana. One hundred and eighteen HIV positive children were recruited at the Korle-Bu Teaching Hospital in Ghana and nasopharyngeal specimens were collected from them. The specimens were cultured for bacteria, and the isolates were identified by standard microbiological methods. Antibiotic susceptibility tests were carried out on selected bacterial organisms by the Kirby Bauer method. Bacteria isolated from the study subjects included Moraxella catarrhalis (39.8%), coagulase negative staphylococci (33.1%), Streptococcus pneumoniae (30.5%), diptheroids (29.7%), viridian streptococci (27.1%), Staphylococcus aureus (22.0%), Citrobacter spp. (4.2%) and Neisseria meningitidis (0.9%). Prevalence of antibiotic resistance of S. pneumoniae ranged from 5.6% (ceftriaxone) to 58.3% (cotrimoxazole), M. catarrhalis ranged from 2.1% (gentamicin) to 80.6% (ampicillin), and S. aureus ranged from 7.7% (cefoxitin) to 100% (penicillin). The prevalence of multiple drug resistance was 16.7% for S. pneumoniae, 57.4% for M. catarrhalis and 84.6% for S. aureus. HIV infected children in the study area commonly carry multi-drug resistant isolates of several pathogenic bacteria such as S. aureus and S. pneumoniae. Infections arising in these patients that are caused by S. aureus and S. pneumoniae could be treated with ceftriaxone and cefoxitin respectively.

  15. β-Lactams and Florfenicol Antibiotics Remain Bioactive in Soils while Ciprofloxacin, Neomycin, and Tetracycline Are Neutralized▿

    Science.gov (United States)

    Subbiah, Murugan; Mitchell, Shannon M.; Ullman, Jeffrey L.; Call, Douglas R.

    2011-01-01

    It is generally assumed that antibiotic residues in soils select for antibiotic-resistant bacteria. This assumption was tested by separately adding 10 different antibiotics (≥200 ppm) to three soil-water slurries (silt-loam, sand-loam, and sand; 20% soil [wt/vol]) and incubating mixtures for 24 h at room temperature. The antibiotic activity of the resultant supernatant was assessed by culturing a sensitive Escherichia coli strain in the filter-sterilized supernatant augmented with Luria-Bertani broth. We found striking differences in the abilities of supernatants to suppress growth of the indicator E. coli. Ampicillin, cephalothin, cefoxitin, ceftiofur, and florfenicol supernatants completely inhibited growth while bacterial growth was uninhibited in the presence of neomycin, tetracycline, and ciprofloxacin supernatants. High-performance liquid chromatography (HPLC) analysis demonstrated that cefoxitin and florfenicol were almost completely retained in the supernatants, whereas tetracycline and ciprofloxacin were mostly removed. Antibiotic dissipation in soil, presumably dominated by adsorption mechanisms, was sufficient to neutralize 200 ppm of tetracycline; this concentration is considerably higher than reported contamination levels. Soil pellets from the tetracycline slurries were resuspended in a minimal volume of medium to maximize the interaction between bacteria and soil particles, but sensitive bacteria were still unaffected by tetracycline (P = 0.6). Thus, residual antibiotics in soil do not necessarily exert a selective pressure, and the degree to which the pharmaceutical remains bioactive depends on the antibiotic. Efforts to control antibiotic contamination would be better directed toward compounds that retain biological activity in soils (e.g., cephalosporins and florfenicol) because these are the antibiotics that could exert a selective pressure in the environment. PMID:21856822

  16. In vitro activities of vancomycin and linezolid against biofilm-producing methicillin-resistant staphylococci species isolated from catheter-related bloodstream infections from an Egyptian tertiary hospital.

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    Hashem, Asmaa A; Abd El Fadeal, Noha M; Shehata, Atef S

    2017-06-01

    Catheter-related bloodstream infections (CRBSIs) are among the most common hospital-acquired infections. We aimed to survey methicillin resistance, biofilm production and susceptibility to vancomycin, linezolid and other antibiotics for staphylococci isolated from CRBSIs. Fifty-eight isolates [20 S. aureus and 38 coagulase-negative staphylococci (CoNS; 20 Staphylococcusepidermidis, nine Staphylococcushaemolyticus, three Staphylococcusschleiferi, two Staphylococcuswarneri and four Staphylococcuslugdunensis)] were tested for methicillin resistance by cefoxitin disk diffusion and detection of the mecA gene by PCR; biofilm-forming ability using Congo red agar and tissue culture plate methods; susceptibility to ciprofloxacin, clindamycin, cotrimoxazole, erythromycin, gentamicin, linezolid, rifampicin and tetracycline; and MIC determination for vancomycin.Results/Key findings. Cefoxitin resistance was detected among 40 % (8/20) S. aureus isolates, 70 % (14/20) S. epidermidis isolates and 16.7 % (3/18) of other CoNS, although the mecA gene was detected in 45 % (9/20) S. aureus isolates, 35 % (7/20) S. epidermidis isolates and 16.7 % (3/18) of other CoNS. Biofilm-forming ability ranged from 45 to 75 %. Methicillin-resistant S. aureus and other CoNS were considered to be more virulent than methicillin-resistant S. epidermidis due to the higher biofilm forming abilities of the former. All tested isolates exhibited 100 % sensitivity to vancomycin and linezolid, irrespective of their methicillin resistance or biofilm-forming ability. Rifampicin showed overall sensitivity of 75.9 %. Varying degrees of multi-resistance were found for the other antibiotics. Vancomycin, linezolid and rifampicin could be used effectively against methicillin-resistant staphylococci isolated from CRBSIs.

  17. Coagulase-negative staphylococci (CoNS) isolated from ready-to-eat food of animal origin--phenotypic and genotypic antibiotic resistance.

    Science.gov (United States)

    Chajęcka-Wierzchowska, Wioleta; Zadernowska, Anna; Nalepa, Beata; Sierpińska, Magda; Łaniewska-Trokenheim, Łucja

    2015-04-01

    The aim of this work was to study the pheno- and genotypical antimicrobial resistance profile of coagulase negative staphylococci (CoNS) isolated from 146 ready-to-eat food of animal origin (cheeses, cured meats, sausages, smoked fishes). 58 strains were isolated, they were classified as Staphylococcus xylosus (n = 29), Staphylococcus epidermidis (n = 16); Staphylococcus lentus (n = 7); Staphylococcus saprophyticus (n = 4); Staphylococcus hyicus (n = 1) and Staphylococcus simulans (n = 1) by phenotypic and genotypic methods. Isolates were tested for resistance to erythromycin, clindamycin, gentamicin, cefoxitin, norfloxacin, ciprofloxacin, tetracycline, tigecycline, rifampicin, nitrofurantoin, linezolid, trimetoprim, sulphamethoxazole/trimethoprim, chloramphenicol, quinupristin/dalfopristin by the disk diffusion method. PCR was used for the detection of antibiotic resistance genes encoding: methicillin resistance--mecA; macrolide resistance--erm(A), erm(B), erm(C), mrs(A/B); efflux proteins tet(K) and tet(L) and ribosomal protection proteins tet(M). For all the tet(M)-positive isolates the presence of conjugative transposons of the Tn916-Tn1545 family was determined. Most of the isolates were resistant to cefoxitin (41.3%) followed by clindamycin (36.2%), tigecycline (24.1%), rifampicin (17.2%) and erythromycin (13.8%). 32.2% staphylococcal isolates were multidrug resistant (MDR). All methicillin resistant staphylococci harboured mecA gene. Isolates, phenotypic resistant to tetracycline, harboured at least one tetracycline resistance determinant on which tet(M) was most frequent. All of the isolates positive for tet(M) genes were positive for the Tn916-Tn1545 -like integrase family gene. In the erythromycin-resistant isolates, the macrolide resistance genes erm(C) or msr(A/B) were present. Although coagulase-negative staphylococci are not classical food poisoning bacteria, its presence in food could be of public health significance due to the possible spread of

  18. β-Lactamase Production in Prevotella intermedia, Prevotella nigrescens, and Prevotella pallens Genotypes and In Vitro Susceptibilities to Selected Antimicrobial Agents

    Science.gov (United States)

    Mättö, Jaana; Asikainen, Sirkka; Väisänen, Marja-Liisa; Von Troil-Lindén, Birgitta; Könönen, Eija; Saarela, Maria; Salminen, Kari; Finegold, Sydney M.; Jousimies-Somer, Hannele

    1999-01-01

    The present study investigated the β-lactamase production of 73 Prevotella intermedia, 84 Prevotella nigrescens, and 14 Prevotella pallens isolates and their in vitro susceptibilities to six antimicrobial agents. The P. intermedia and P. nigrescens isolates were recovered from oral and extraoral samples obtained from subjects in two geographic locations from 1985 to 1995. The clonality of the β-lactamase-positive and β-lactamase-negative isolates and the clustering of the genotypes were studied by arbitrarily primed-PCR fingerprinting. β-Lactamase production was detected in 29% of P. intermedia isolates, 29% of P. nigrescens isolates, and 57% of P. pallens isolates. No difference in the frequencies of β-lactamase production by P. intermedia and P. nigrescens between isolates from oral and extraoral sites, between isolates obtained at different time periods, or between P. intermedia isolates from different geographic locations was observed. However, the P. nigrescens isolates from the United States were significantly more frequently (P = 0.015) β-lactamase positive than those from Finland. No association between the genotypes and β-lactamase production or between the genotypes and the sources of the isolates was found. The penicillin G MICs at which 90% of the isolates were inhibited were 8 μg/ml for P. intermedia, 8 μg/ml for P. nigrescens, and 16 μg/ml for P. pallens. For the β-lactamase-negative isolates, the corresponding values were 0.031, 0.031, and 0.125 μg/ml, and for the β-lactamase-positive isolates, the corresponding values were 16, 8, and 32 μg/ml. All isolates were susceptible to amoxicillin-clavulanate, cefoxitin, metronidazole, azithromycin, and trovafloxacin. The MICs of amoxicillin-clavulanate and cefoxitin were relatively higher for the β-lactamase-positive population than for the β-lactamase-negative population. PMID:10508011

  19. Panton-Valentine Leukocidin gene positive methicillin resistant Staphylococcus aureus, the community strains causing infections in intensive care unit - High risk of outbreak and preventing strategies

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    Mowna Karthik

    2016-07-01

    Full Text Available Methicillin resistant Staphylococcus aureus (MRSA is an important pathogen that causes hospital acquired infections recorded in the intensive care unit (ICU. Most of the MRSA isolates carry mecA gene which is a molecular marker for Methicilin resistance. There are two types of MRSA , community acquired (C and ndash;MRSA and hospital acquired (H-MRSA, both of these contain mecA gene. The Panton-Valentine Leukocidin (PVL gene is normally present in C-MRSA infections which are now found to be widespread in hospital setting. Our objective was to assess the presence of PVL gene in mecA gene positive MRSA isolates from ICUs. This was a cross sectional study in ICUs of a tertiary care hospital over a period of 8 months (June 2013 to January 2014. Total of two hundred patients admitted in the ICUs who were suspected to have acquired infection 48 hours after admission were included in the study. By routine bacteriological examination and disc diffusion sensitivity testing with 30 and #956;g cefoxitin discs, MRSA strains were isolated. Polymerized chain reaction (PCR was performed to detect mecA gene and PVL gene using specific primers. Cefoxitin disc diffusion screening showed 112 positive MRSA strains among which the mecA gene was detected in 104 strains and was absent in the remaining eight strains of total MRSA. Among the 104 mecA gene positive MRSA strains, 46 (44% strains contained PVL gene. Our results indicate a higher prevalence of PVL-positive MRSA strains in the ICUs compared to many earlier studies. These strains were susceptible only to very few antibiotics and the empirical treatment options should be planned accordingly. Awareness of intensive care physicians and proper training of health care workers in the ICU could lower the magnitude of this problem. [J Med Allied Sci 2016; 6(2.000: 56-60

  20. Low prevalence of methicillin resistant Staphylococcus aureus as determined by an automated identification system in two private hospitals in Nairobi, Kenya: a cross sectional study.

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    Omuse, Geoffrey; Kabera, Beatrice; Revathi, Gunturu

    2014-12-14

    Staphylococcus aureus (S.aureus) is a major cause of both healthcare and community acquired infections. In developing countries, manual phenotypic tests are the mainstay for the identification of staphylococci with the tube and slide coagulase tests being relied upon as confirmatory tests for S. aureus. The subjectivity associated with interpretation of these tests may result in misidentification of coagulase negative staphylococci as S.aureus. Given that antibiotic resistance is more prevalent in CONS, this may result in over estimation of methicillin resistant S.aureus (MRSA) prevalence. A review of susceptibility data from all non-duplicate S.aureus isolates generated between March 2011 and May 2013 by the Vitek-2 (bioMérieux) automated system was performed by the authors. The data was generated routinely from processed clinical specimens submitted to the microbiology laboratories for culture and sensitivity at the Aga Khan University Hospital and Gertrude's children's hospital both situated in Nairobi. Antimicrobial susceptibility data from a total of 731 non-duplicate S.aureus isolates was reviewed. Majority (79.2%) of the isolates were from pus swabs. Only 24 isolates were both cefoxitin and oxacillin resistant while 3 were resistant to oxacillin but susceptible to cefoxitin giving an overall MRSA prevalence of 3.7% (27/731). None of the isolates were resistant to mupirocin, linezolid, tigecycline, teicoplanin or vancomycin. The prevalence of MRSA in this study is much lower than what has been reported in most African countries. The significant change in antibiotic susceptibility compared to what has previously been reported in our hospital is most likely a consequence of the transition to an automated platform rather than a trend towards lower resistance rates.

  1. Antibiotic resistance in Escherichia coli isolates from roof-harvested rainwater tanks and urban pigeon faeces as the likely source of contamination.

    Science.gov (United States)

    Chidamba, Lizyben; Korsten, Lise

    2015-07-01

    The objective of this study was to investigate the risks associated with the use of roof-harvested rainwater (RHRW) and the implication of pigeons as the most likely source of contamination by testing for antibiotic resistance profiles of Escherichia coli. A total of 239 E. coli were isolated from thirty fresh pigeon faecal samples (130 isolates), 11 RHRW tanks from three sites in Pretoria (78) and two in Johannesburg (31). E. coli isolates were tested against a panel of 12 antibiotics which included ampicillin, amoxicillin, amikacin, cefoxitin, ceftriaxone, chloramphenicol, ciprofloxacin, cotrimoxazole, enrofloxacin, gentamicin, nalidixic acid and tetracycline. In all samples, resistance to ampicillin (22.7.9%), gentamicin (23.6%), amikacin (24%), tetracycline (17.4) and amoxicillin (16.9%) were the most frequently encountered form of resistance. However, a relatively higher proportion of isolates from pigeon faeces (67.3%) were antibiotic resistant than those from RHRW (53.3%). The highest number of phenotypes was observed for single antibiotics, and no single antibiotic resistance was observed for chloramphenicol, ceftriaxone, gentamicin, cefoxitin, cotrimoxazole, although they were detected in multiple antibiotic resistance (MAR) phenotypes. The highest multiple antibiotic resistance (MAR) phenotypes were observed for a combination of four antibiotics, on isolates from JHB (18.8%), pigeon faeces (15.2%) and Pretoria (5.1%). The most abundant resistance phenotype to four antibiotics, Ak-Gm-Cip-T was dominated by isolates from pigeon faeces (6.8%) with Pretoria and Johannesburg isolates having low proportions of 1.3 and 3.1%, respectively. Future studies should target isolates from various environmental settings in which rainwater harvesting is practiced and the characterisation of the antibiotic resistance determinant genes among the isolates.

  2. Genotypic and Phenotypic Detection of AmpC β-lactamases in Enterobacter spp. Isolated from a Teaching Hospital in Malaysia.

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    Mohd Khari, Fatin Izzati; Karunakaran, Rina; Rosli, Roshalina; Tee Tay, Sun

    2016-01-01

    The objective of this study was to determine the occurrence of chromosomal and plasmid-mediated β-lactamases (AmpC) genes in a collection of Malaysian isolates of Enterobacter species. Several phenotypic tests for detection of AmpC production of Enterobacter spp. were evaluated and the agreements between tests were determined. Antimicrobial susceptibility profiles for 117 Enterobacter clinical isolates obtained from the Medical Microbiology Diagnostic Laboratory, University Malaya Medical Centre, Malaysia, from November 2012-February 2014 were determined in accordance to CLSI guidelines. AmpC genes were detected using a multiplex PCR assay targeting the MIR/ACT gene (closely related to chromosomal EBC family gene) and other plasmid-mediated genes, including DHA, MOX, CMY, ACC, and FOX. The AmpC β-lactamase production of the isolates was assessed using cefoxitin disk screening test, D69C AmpC detection set, cefoxitin-cloxacillin double disk synergy test (CC-DDS) and AmpC induction test. Among the Enterobacter isolates in this study, 39.3% were resistant to cefotaxime and ceftriaxone and 23.9% were resistant to ceftazidime. Ten (8.5%) of the isolates were resistant to cefepime, and one isolate was resistant to meropenem. Chromosomal EBC family gene was amplified from 36 (47.4%) E. cloacae and three (25%) E. asburiae. A novel blaDHA type plasmid-mediated AmpC gene was identified for the first time from an E. cloacae isolate. AmpC β-lactamase production was detected in 99 (89.2%) of 111 potential AmpC β-lactamase producers (positive in cefoxitin disk screening) using D69C AmpC detection set. The detection rates were lower with CC-DDS (80.2%) and AmpC induction tests (50.5%). There was low agreement between the D69C AmpC detection set and the other two phenotypic tests. Of the 40 isolates with AmpC genes detected in this study, 87.5%, 77.5% and 50.0% of these isolates were positive by the D69C AmpC detection set, CC-DDS and AmpC induction tests, respectively

  3. Prevalence and characterization of methicillin-resistant Staphylococcus aureus carrying mecA or mecC and methicillin-susceptible Staphylococcus aureus in dairy sheep farms in central Italy.

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    Giacinti, G; Carfora, V; Caprioli, A; Sagrafoli, D; Marri, N; Giangolini, G; Amoruso, R; Iurescia, M; Stravino, F; Dottarelli, S; Feltrin, F; Franco, A; Amatiste, S; Battisti, A

    2017-10-01

    Between January and May 2012, a total of 286 bulk tank milk samples from dairy sheep farms located in central Italy were tested for the presence of Staphylococcus aureus. One hundred fifty-three samples were positive for S. aureus (53.5%), with an average count of 2.53 log cfu/mL. A total of 679 S. aureus colonies were screened for methicillin resistance by the cefoxitin disk diffusion test, and 104 selected cefoxitin-susceptible isolates were also tested for their susceptibility to other antimicrobials representative of the most relevant classes active against Staphylococcus spp. by using the Kirby-Bauer disk diffusion method. Two methicillin-resistant Staphylococcus aureus (MRSA) isolates, carrying respectively the mecA and the mecC genes, were detected in 2 samples from 2 different farms (prevalence 0.7%). The mecA-positive MRSA isolate was blaZ positive, belonged to spa type t127, sequence type (ST)1, clonal complex (CC)1, carried a staphylococcal cassette chromosome mec (SCCmec) type IVa, and was phenotypically resistant to all the β-lactams tested and to erythromycin, streptomycin, kanamycin, and tetracycline. The mecC-positive MRSA isolate was negative for the chromosomally or plasmid-associated blaZ gene but positive for the blaZ allotype associated with SCCmec XI (blaZ-SCCmecXI), belonged to spa type 843, ST(CC)130, carried a SCCmec type XI, and was resistant only to β-lactams. Both MRSA were negative for the presence of specific immune-evasion and virulence genes such as those coding for the Panton-Valentine leucocidin, the toxic shock syndrome toxin 1, and the immune evasion cluster genes. Regarding the presence of the major S. aureus enterotoxin genes, the mecC-positive MRSA tested negative, whereas the ST (CC)1 mecA-positive MRSA harbored the seh gene. Among the 104 methicillin-susceptible S. aureus isolates examined for antimicrobial susceptibility, 63 (60.58%) were susceptible to all the antimicrobials tested, and 41 (39.42%) were resistant to at

  4. Antibioticoterapia profilática em obstetrícia: comparação entre esquemas Prophylactic antibiotic treatment in obstetrics: comparison of regimens

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    Heraldo Francisco Costa

    1998-10-01

    group where all patients received three doses of 1 g EV cefalotin at six-hour intervals. In the medium risk group, the incidence of puerperal infection was 5.3% for the patients who used three doses of 1 g EV cefoxitin; 5.1% for those who used three doses of 1 g EV cefalotin; 4.0% when a single cefoxitin dose was used and 3.4% when a single cefalotin dose was used. Conclusions: it is not necessary to use prophylactic antibiotic therapy in low risk patients and the first generation cephalosporins (cefalotin are as efficacious as the second generation cephalosporins (cefoxitin to prevent puerperal infection, independent of the applied dosage. Cefalotin seems to be effective in preventing puerperal infection in patients at high risk.

  5. Detection of AmpC β-lactamase-producing Gram-negative bacteria by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

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    Li, C; Ding, S; Huang, Y; Wang, Z; Shen, J; Ling, H; Xu, Y

    2017-11-22

    Rapid detection of AmpC-producing strains of Gram-negative bacteria is beneficial for patient care. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a novel method that has demonstrated the resistance of a strain to β-lactam antibiotics by determining the molecular structure of an antibiotic and its degradation products. To study the detection of AmpC-producing Gram-negative bacteria by MALDI-TOF MS and to determine whether the method can be used in clinical practice. A total of 105 strains were detected by determining their phenotypes and sequence analysis. Sixty-nine well-characterized AmpC-producing and 36 non-AmpC-producing strains were studied. The bacteria were incubated in different reaction buffer solutions (10 mM NH 4 HCO 3 /0.005% sodium dodecyl sulphate at pH 8.0) containing cefotaxime (0.50 mg/mL), ceftazidime (0.25 mg/mL), ceftriaxone (0.50 mg/mL), cefepime (0.50 mg/mL), and cefoxitin (0.25 and 0.50 mg/mL), respectively. The mixture was centrifuged at 13,000 g for 2 min, and the supernatant analysed by MALDI-TOF MS after incubation for 30, 60, 90, 120, and 240 min. Antibiotic hydrolysed and decarboxylated peaks were identified. When incubated for 90 min, hydrolysed cefotaxime formed peaks at 434 and 494 Da, and the sensitivity and specificity for detection of AmpC-producing strains were 85.5% (59/69) and 88.9% (32/36). When incubated for 4 h, hydrolysed ceftazidime formed peaks at 563 and 587 Da, and the sensitivity and specificity were 89.9% (62/69) and 94.5% (34/36), respectively. For hydrolysed ceftriaxone (0.5 mg/mL), cefepime (0.5 mg/mL) and two concentrations of cefoxitin (0.25 and 0.5 mg/mL), no peaks amenable to analysis were identified. This study demonstrated that MALDI-TOF MS can rapidly detect AmpC-producing strains. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  6. Occurrence of extended-spectrum and AmpC β-lactamases in multiple drug resistant Salmonella isolates from clinical samples in Lagos, Nigeria

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    Akinyemi KO

    2017-01-01

    Full Text Available KO Akinyemi,1 Bamidele Abiodun Iwalokun,2 Akeeb O Bola Oyefolu,1 CO Fakorede1 1Department of Microbiology, Lagos State University, Ojo, 2Molecular Biology and Biotechnology Division, Nigerian Institute of Medical Research, Yaba, Lagos, Nigeria Purpose: Salmonella spp. are important foodborne pathogens exhibiting increasing resistance to antimicrobial drugs. Resistance to broad-spectrum β-lactams, mediated by extended-spectrum β-lactamase (ESBL and AmpC β-lactamase enzymes is fast spreading and has had negative impacts on the clinical outcomes, particularly on third-generation cephalosporins. This study investigated the carriage of AmpC gene among multidrug-resistant Salmonella spp. from Lagos, Nigeria. Methods: Forty Salmonella spp. from clinical samples (S. typhi = 13; S. typhimurium = 10; S. enteritidis = 8; S. choleraesuis = 5; S. paratyphi = 4 were subjected to in vitro susceptibility test by disk diffusion methods. Isolates that were resistant to cefoxitin and third-generation cephalosporins were screened for ESBL (Double Disk Synergy Test Method and AmpC enzyme (AmpC disk test production. Detection of AmpC fox gene was carried out by polymerase chain reaction. Results: Thirty-two (80% of the Salmonella isolates were cefoxitin resistant. Plasmid-mediated AmpC β-lactamase and ESBL enzymes were recorded in 10/40 (25% and 16/40 (40% of the Salmonella isolates, respectively. Specifically, 16/40 (40% of the Salmonella isolates possessed 380 bp AmpC fox gene, with the highest occurrence found in S. typhi strains (43.8% followed by S. typhimurium (25%. There was no AmpC fox gene detected in S. paratyphi strains. Interestingly, coproduction of enzymes occurred in some of the isolates, raising fears of resistance to a multitude of antibiotics in the treatment of bacterial infections. Conclusion: Emergence of AmpC β-lactamase–producing Salmonella isolates in our environment was recorded for the first time, raising concern on increased

  7. Frequent occurrence of oxacillin-susceptible mecA-positive Staphylococcus aureus (OS-MRSA) strains in two African countries.

    Science.gov (United States)

    Conceição, Teresa; Coelho, Céline; de Lencastre, Hermínia; Aires-de-Sousa, Marta

    2015-12-01

    Oxacillin-susceptible mecA-positive Staphylococcus aureus (OS-MRSA) isolates have been increasingly reported worldwide, but data regarding the African continent have not been available. Between 2010 and 2014, 1462 inpatients and healthcare workers were screened for MRSA nasal carriage in São Tomé and Príncipe (STP) and Angola, two Portuguese-speaking African countries (PALOP countries). We determined the presence of the mecA gene and the antimicrobial susceptibility profiles of the isolates. OS-MRSA clonal lineages were identified as well as the presence of virulence determinants, including Panton-Valentine leucocidin (PVL). Out of 164 S. aureus hospital isolates tested, 29 (17.7%) were mecA positive, but susceptible to oxacillin, showing oxacillin MICs ≤3 mg/L. All OS-MRSA isolates were resistant to cefoxitin and most of them were also resistant to at least two antimicrobials other than β-lactams. The 29 OS-MRSA were distributed into two major clonal lineages: (i) PFGE type B-ST88-SCCmec IVa, associated with spa types t186/t325/t786/t1814/t1951, detected in Angola (n = 5) and STP (n = 10); and (ii) PFGE type C-t451/t648-ST8-SCCmec V, exclusively found in STP (n = 9). OS-MRSA showed at least two virulence determinants. PVL was detected in an isolate recovered in STP. We describe a high prevalence of OS-MRSA among S. aureus strains recovered in two African countries. OS-MRSA in PALOP countries were mainly associated with ST88 and ST8, two prevalent MRSA clonal types in these countries. If direct testing for mecA is not available, cefoxitin susceptibility testing is highly recommended to avoid the misidentification of OS-MRSA. © The Author 2015. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  8. Comparative antimicrobial susceptibility of aerobic and facultative bacteria from community-acquired bacteremia to ertapenem in Taiwan

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    Fung Chang-Phone

    2007-07-01

    Full Text Available Abstract Background Ertapenem is a once-a-day carbapenem and has excellent activity against many gram-positive and gram-negative aerobic, facultative, and anaerobic bacteria. The susceptibility of isolates of community-acquired bacteremia to ertapenem has not been reported yet. The present study assesses the in vitro activity of ertapenem against aerobic and facultative bacterial pathogens isolated from patients with community-acquired bacteremia by determining and comparing the MICs of cefepime, cefoxitin, ceftazidime, ceftriaxone, ertapenem, piperacillin, piperacillin-tazobactam, ciprofloxacin, amikacin and gentamicin. The prevalence of extended broad spectrum β-lactamases (ESBL producing strains of community-acquired bacteremia and their susceptibility to these antibiotics are investigated. Methods Aerobic and facultative bacteria isolated from blood obtained from hospitalized patients with community-acquired bacteremia within 48 hours of admission between August 1, 2004 and September 30, 2004 in Chang Gung Memorial Hospital at Keelung, Taiwan, were identified using standard procedures. Antimicrobial susceptibility was evaluated by Etest according to the standard guidelines provided by the manufacturer and document M100-S16 Performance Standards of the Clinical Laboratory of Standard Institute. Antimicrobial agents including cefepime, cefoxitin, ceftazidime, ceftriaxone, ertapenem, piperacillin, piperacillin-tazobactam, ciprofloxacin, amikacin and gentamicin were used against the bacterial isolates to test their MICs as determined by Etest. For Staphylococcus aureus isolates, MICs of oxacillin were also tested by Etest to differentiate oxacillin-sensitive and oxacillin-resistant S. aureus. Results Ertapenem was highly active in vitro against many aerobic and facultative bacterial pathogens commonly recovered from patients with community-acquired bacteremia (128/159, 80.5 %. Ertapenem had more potent activity than ceftriaxone, piperacillin

  9. Evaluación de cuatro métodos para la detección de Staphylococcus aureus meticilino-resistente de muestras clínicas en un hospital regional Evaluation of four methods for detecting methicillin-resistant Staphylococcus aureus isolates from clinical specimens at a regional hospital in Mexico

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    Gabriel Acosta-Pérez

    2012-02-01

    Full Text Available OBJETIVO: Investigar la prevalencia de Staphylococcus aureus meticilino-resistente (MRSA en aislados clínicos y determinar la concordancia entre los métodos de detección de MRSA en un laboratorio con recursos y personal limitado. MATERIAL Y MÉTODOS: Se analizaron 140 cepas de Staphylococcus aureus aisladas de muestras clínicas de diferentes departamentos mediante pruebas convencionales: producción de β-lactamasa, sensibilidad a oxacilina con MIC-Vitek 2-XL, ChromID MRSA, difusión en agar para discos de 30 μg de cefoxitina, detección de PBP2a y PCR para el gen mecA. Se determinó el índice kappa de Cohen, para evaluar la concordancia entre los diferentes métodos utilizados. RESULTADOS: La prevalencia encontrada fue de 90.7%. La sensibilidad y especificidad para los diferentes métodos de detección fue: difusión en disco para cefoxitina 97 y 92% respectivamente, MIC Vitek 2-XL 97 y 69%, ChromoID MRSA 97 y 85% y detección de PBP2a 98 y 100%. CONCLUSIONES: Todos los métodos son muy buenos para la detección de MRSA; la elección en el uso de cada método dependerá de la infraestructura de cada laboratorio.OBJETIVE: To estimate the prevalence of methicillin-resistant Staphylococcus aureus (MRSA in clinical isolates and to compare different methods for detection of MRSA in a lab with limited available personnel and resources. MATERIAL AND METHODS: 140 Staphylococcus aureus strains isolated from patients in several departments were assayed for β-lactamase production, MIC-Vitek 2 oxacillin, ChromID MRSA, disk diffusion in agar for cefoxitin 30 μg and PBP2a detection. The results of conventional tests were compared with the "gold standard" PCR test for mecA gene. Cohen´s kappa index was also calculated in order to evaluate the intra assay agreement between the used methods. RESULTS: The found prevalence was 90.7%. Sensitivity and specificity were: disk diffusion for cefoxitin 97 and 92% respectively, MIC Vitek 2-XL 97 and 69%, Chromo

  10. Prevalence of Enterotoxin Genes and Antibacterial Susceptibility Pattern of Staphylococcus aureus Strains Isolated from Animal Originated Foods in West of Iran

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    Rasoul Y. Mashouf

    2015-07-01

    Full Text Available Objectives: The aims of our study were to evaluate the prevalence of Staphylococcus aureus (S. aureus strains in food samples of animal origin, examine their antibacterial susceptibility pattern, and to detect staphylococcal enterotoxin (SEs genes and the mecA gene in isolated S. aureus strains using the polymerase chain reaction (PCR. Methods: A total of 1050 food samples including 671 raw milk and dairy products and 379 raw meats were collected between September 2013 and June 2014 in Hamadan, Iran. Food samples were analyzed for S. aureus identification. The antibiotic susceptibility pattern of all isolates was determined using the disk agar diffusion method followed by detecting mecA resistance gene using PCR. In addition, harboring of SE genes were determined using a multiplex PCR assay targeting nine genes.  Results: A total of 98 (9.3% S. aureus strains were isolated from 1050 food samples. Of the 98 isolates examined, the most frequent resistance was observed to erythromycin (30.6%, followed by tetracycline (29.6%, gentamicin (27.6%, clindamycin (26.5%, ciprofloxacin and rifampin (24.5%, trimethoprim-sulfamethoxazole (14.3%, and cefoxitin (5.1%. All cefoxitin resistant isolates were positive for mecA. The prevalence of SEs was 77.6% (n=76. Among the genes that code classic enterotoxins, sea was the most frequent and was carried by 25.5% of isolates, followed by see in 18.4%, sed in 11.2%, sec in 5.1%, and seb in 4.1% of isolates. Among the detected enterotoxins, seg was the predominantly identified enterotoxin gene in isolates with prevalence of 35.7%. The seh gene with prevalence of 1% and sei gene with 3.1% were other detected enterotoxins with low frequencies.  Conclusion: The high prevalence of SE genes detected indicates a potential risk for causing animal-originated food poisoning. The increasing prevalence of community-acquired MRSA and its emerging antibiotic resistance in foods is a serious problem for public health.

  11. [Antimicrobial susceptibility and drug-resistance genes of Yersinia spp. of retailed poultry in 4 provinces of China].

    Science.gov (United States)

    Peng, Z X; Zou, M Y; Xu, J; Guan, W Y; Li, Y; Liu, D R; Zhang, S S; Hao, Q; Yan, S F; Wang, W; Yu, D M; Li, F Q

    2018-04-06

    Objective: To monitor the antimicrobial resistance and drug-resistance genes of Yersinia enterocolitis , Y. intermedia and Y. frederiksenii recovered from retailed fresh poultry of 4 provinces of China. Methods: The susceptibility of 25 isolated Yersinia spp. to 14 classes and 25 kinds of antibiotics was determined by broth microdilution method according to CLSI (Clinical and Laboratory Standards Institute). The antibiotic resistance genes were predicted with antibiotic resistance genes database (ARDB) using whole genome sequences of Yersinia spp. Results: In all 22 Y. enterocolitis tested, 63.7% (14 isolates), 22.8% (5 isolates), 4.6% and 4.6% of 1 isolates exhibited the resistance to cefoxitin, ampicillin-sulbactam, nitrofurantoin and trimethoprim-sulfamethoxazole, respectively. All the 25 isolates were multi-drug resistant to more than 3 antibiotics, while 64.0% of isolates were resistant to more than 4 antibiotics. A few Y. enterocolitis isolates of this study were intermediate to ceftriaxone and ciprofloxacin. Most Yersinia spp. isolates contained antibiotic resistance genes mdtG, ksgA, bacA, blaA, rosAB and acrB , and 5 isolates recovered from fresh chicken also contained dfrA 1, catB 2 and ant 3 ia . Conclusion: The multi-drug resistant Yersinia spp. isolated from retailed fresh poultry is very serious in the 4 provinces of China, and their contained many kinds of drug-resistance genes.

  12. Prevalence of Antibiotic-resistance Enterobacteriaceae strains Isolated from Chicken Meat at Traditional Markets in Surabaya, Indonesia

    Science.gov (United States)

    Yulistiani, R.; Praseptiangga, D.; Supyani; Sudibya; Raharjo, D.; Shirakawa, T.

    2017-04-01

    Antibiotic resistance in bacteria from the family Enterobacteriaceae is an important indicator of the emergence of resistant bacterial strains in the community. This study investigated the prevalence of antibiotic-resistant Enterobacteriaceae isolated from chicken meat sold at traditional markets in Surabaya Indonesia. In all, 203 isolates (43 Salmonella spp., 53 Escherichia coli, 16 Shigella spp., 22 Citrobacter spp., 13 Klebsiella spp, 24 Proteus spp., 15 Yersinia spp., 7 Enterobacter spp., 6 Serratia spp., 3 Edwardsiella spp. were resistant to tetracycline (69.95 %), nalidixid acid (54.19 %), sulfamethoxazole/sulfamethizole (42.36 %), chloramphenicol (12.81%), cefoxitin (6.40 %), gentamicin (5.91 %). Tetracycline was the antimicrobial that showed the highest frequency of resistance among Salmonella, E. coli, Citrobacter, Proteus and Erdwardsiella isolates, and nalidixid acid was second frequency of resistance. Overall, 124 (61.08 %) out of 203 isolates demonstrated multidrug resistance to at least two unrelated antimicrobial agents. The high rate of antimicrobial resistance in bacterial isolates from chicken meat may have major implications for human and animal health with adverse economic implications.

  13. Rapid screening of pyogenic Staphylococcus aureus for confirmation of genus and species, methicillin resistance and virulence factors by using two novel multiplex PCR

    Science.gov (United States)

    Haque, Abdul; Haque, Asma; Saeed, Muhammad; Azhar, Aysha; Rasool, Samreen; Shan, Sidra; Ehsan, Beenish; Nisar, Zohaib

    2017-01-01

    Objectives: Emergence of methicillin resistant Staphylococcus aureus (MRSA) is a major medical problem of current era. These bacteria are resistant to most drugs and rapid diagnosis can provide a clear guideline to clinicians. They possess specific virulence factors and relevant information can be very useful. We designed this study to develop multiplex PCRs to provide rapid information. Methods: We studied 60 Staphylococcus aureus isolates and detected methicillin resistance by cefoxitin sensitivity and targeting of mecA gene. After initial studies with uniplex PCRs we optimized two multiplex PCRs with highly reproducible results. The first multiplex PCR was developed to confirm genus, species and methicillin resistance simultaneously, and the second multiplex PCR was for screening of virulence factors. Results: We found 38.33% isolates as methicillin resistant. α -toxin, the major cytotoxic factor, was detected in 40% whereas β-hemolysin was found in 25% cases. Panton Valentine leucocidin was detected in 8.33% and toxic shock syndrome toxin in5% cases. The results of uniplex and multiplex PCRs were highly compatible. Conclusions: These two multiplex PCRs when run simultaneously can provide vital information about methicillin resistance and virulence status of the isolate within a few hours as compared to several days needed by routine procedures. PMID:29142545

  14. Phenotypic and genotypic detection of methicillin-resistant Staphylococcus aureus in hunting dogs in Maiduguri metropolitan, Borno State, Nigeria.

    Science.gov (United States)

    Mustapha, Muhammad; Bukar-Kolo, Yachilla Maryam; Geidam, Yaqub Ahmed; Gulani, Isa Adamu

    2016-05-01

    To determine the presence of MRSA in hunting dogs in Maiduguri metropolitan. Phenotypic methods used includes microscopic technique, colony morphology study, catalase-coagulase tests, and the use of mannitol salt agar test, oxacillin resistance screening agar base, and antibiotic susceptibility testing methods. Genotypic approach was used for deoxyribonucleic acid extraction, and the presence of nuc and mecA gene was detected using polymerase chain reaction (PCR) techniques. Examination of 416 swab samples from nasal and perineal region of dogs revealed a total of 79.5% of S. aureus, where 62.5% of the isolates were MRSA. Molecular analysis revealed that 7nuc genes specific for S. aureus from 20 presumptive MRSA assay were all mecA PCR negative. The isolates were sensitive to gentamicin and ciprofloxacin but proved resistant to cefoxitin and oxacillin. High isolation rate of MRSA was found in hunting dogs. Significant level (p<0.05) of MRSA was isolated in the nasal cavity of hunting dogs than its perineum. Only nuc genes were detected from the MRSA isolates.

  15. Berberine Enhances the Antibacterial Activity of Selected Antibiotics against Coagulase-Negative Staphylococcus Strains in Vitro

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    Robert D. Wojtyczka

    2014-05-01

    Full Text Available Synergistic interactions between commonly used antibiotics and natural bioactive compounds may exhibit therapeutic benefits in a clinical setting. Berberine, an isoquinoline-type alkaloid isolated from many kinds of medicinal plants, has proven efficacy against a broad spectrum of microorganisms. The aim of the presented work was to assess the antibacterial activity of berberine chloride in light of the effect exerted by common antibiotics on fourteen reference strains of Staphylococccus spp., and to evaluate the magnitude of interactions of berberine with these antistaphylococcal antibiotics. In our study minimum inhibitory concentrations (MIC of berberine chloride against CoNS ranged from 16 to 512 µg/mL. The most noticeable effects were observed for S. haemolyticus ATCC 29970, S. epidermidis ATCC 12228, S. capitis subsp. capitis ATCC 35661, S. galinarium ATCC 700401, S. hominis subsp. hominis ATCC 27844, S. intermedius ATCC 29663 and S. lugdunensis ATCC 49576. The most significant synergistic effect was noticed for berberine in combination with linezolid, cefoxitin and erythromycin. The synergy between berberine and antibiotics demonstrates the potential application of compound combinations as an efficient, novel therapeutic tool for antibiotic-resistant bacterial infections.

  16. Pseudomonas pseudomallei, a common pathogen in Thailand that is resistant to the bactericidal effects of many antibiotics.

    Science.gov (United States)

    Sookpranee, T; Sookpranee, M; Mellencamp, M A; Preheim, L C

    1991-03-01

    The purpose of this investigation was to identify newer antimicrobial agents that may be useful in the therapy of melioidosis. The in vitro susceptibilities of 199 clinical isolates of Pseudomonas pseudomallei to 22 antibiotics were determined by standard disk diffusion, and those to 13 antibiotics were determined by agar dilution. Over 90% of the isolates were susceptible to imipenem, piperacillin-tazobactam, piperacillin, ceftazidime, ticarcillin-clavulanate, ampicillin-sulbactam, and carumonam by both methods. Standard disk diffusion yielded unacceptably high false-susceptibility results with aztreonam, ciprofloxacin, and temafloxacin. Piperacillin, ceftazidime, imipenem, and ciprofloxacin were not bactericidal for three selected P. pseudomallei strains as determined by time-kill curve methods. Furthermore, addition of ciprofloxacin to piperacillin, ceftazidime, or imipenem did not enhance bactericidal activity. One hundred ninety-four strains showed weak beta-lactamase production that did not increase upon incubation with cefoxitin. These findings suggest that several newer antimicrobial agents may prove useful in the treatment of melioidosis. However, results of susceptibility studies involving P. pseudomallei and newer agents must be interpreted with caution.

  17. Epidemiology, Clinical Characteristics, and Antimicrobial Susceptibility Profiles of Human Clinical Isolates of Staphylococcus intermedius Group.

    Science.gov (United States)

    Yarbrough, Melanie L; Lainhart, William; Burnham, C A

    2018-03-01

    The veterinary pathogens in the Staphylococcus intermedius group (SIG) are increasingly recognized as causes of human infection. Shared features between SIG and Staphylococcus aureus may result in the misidentification of SIG in human clinical cultures. This study examined the clinical and microbiological characteristics of isolates recovered at a tertiary-care academic medical center. From 2013 to 2015, 81 SIG isolates were recovered from 62 patients. Patients were commonly ≥50 years old, diabetic, and/or immunocompromised. Documentation of dog exposure in the electronic medical record was not common. Of the 81 SIG isolates, common sites of isolation included 37 (46%) isolates from wound cultures and 17 (21%) isolates from respiratory specimens. Although less common, 10 (12%) bloodstream infections were documented in 7 unique patients. The majority of SIG (65%) isolates were obtained from polymicrobial cultures. In comparison to S. aureus isolates from the same time period, significant differences were noted in proportion of SIG isolates that were susceptible to doxycycline (74% versus 97%, respectively; P SIG isolates. All MR isolates detected by an oxacillin disk diffusion test would have been misclassified as methicillin susceptible using a cefoxitin disk diffusion test. Thus, SIG is recovered from human clinical specimens, and distinction of SIG from S. aureus is critical for the accurate characterization of MR status in these isolates. Copyright © 2018 American Society for Microbiology.

  18. Multicenter Evaluation of the Portrait Staph ID/R Blood Culture Panel for Rapid Identification of Staphylococci and Detection of themecAGene.

    Science.gov (United States)

    Denys, Gerald A; Collazo-Velez, Vanessa; Young, Stephen; Daly, Judy A; Couturier, Marc Roger; Faron, Matthew L; Buchan, Blake W; Ledeboer, Nathan

    2017-04-01

    Bloodstream infections are a leading cause of morbidity and mortality in the United States and are associated with increased health care costs. We evaluated the Portrait Staph ID/R blood culture panel (BCP) multiplex PCR assay (Great Basin Scientific, Salt Lake City, UT) for the rapid and simultaneous identification (ID) of Staphylococcus aureus , Staphylococcus lugdunensis , and Staphylococcus species to the genus level and the detection of the mecA gene directly from a positive blood culture bottle. A total of 765 Bactec bottles demonstrating Gram-positive cocci in singles or clusters were tested during the prospective trial at 3 clinical sites. The Portrait Staph ID/R BCP results were compared with results from conventional biochemical and cefoxitin disk methods performed at an independent laboratory. Discordant ID and mecA results were resolved by rpoB gene sequencing and mecA gene sequencing, respectively. A total of 658 Staphylococcus species isolates ( S. aureus , 211 isolates; S. lugdunensis , 3 isolates; and Staphylococcus spp., 444 isolates) were recovered from monomicrobial and 33 polymicrobial blood cultures. After discrepant analysis, the overall ratios of Portrait Staph ID/R BCP positive percent agreement and negative percent agreement were 99.4%/99.9% for Staphylococcus ID and 99.7%/99.2% for mecA detection. Copyright © 2017 American Society for Microbiology.

  19. Inducible clindamycin resistance in Staphylococcus species.

    Science.gov (United States)

    Afridi, Faisal Iqbal; Zeb, Mubarak; Hussain, Arif; Farooqi, Badar Jahan; Murtuza, Ghulam

    2014-07-01

    To determine the frequency of inducible clindamycin resistance in clinical isolates of Staphylococcus species by phenotypic D-test. Observational study. Ziauddin University Hospital, Karachi, from July to December 2011. 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. 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. 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.

  20. Prevalence and characterization of Staphylococcus aureus and Staphylococcus pseudintermedius isolated from companion animals and environment in the veterinary teaching hospital in Zambia, Africa.

    Science.gov (United States)

    Youn, Jung-Ho; Park, Yong Ho; Hang'ombe, Bernard; Sugimoto, Chihiro

    2014-03-01

    The Republic of Zambia consists of only one veterinary teaching school at the University of Zambia (UNZA) where students and veterinarians are exposed to many bacterial pathogens including Staphylococcus aureus (SA) and Staphylococcus pseudintermedius (SP). The aim of this study was the characterization and antimicrobial susceptibility profile of eleven SA and 48 SP isolates from the veterinary hospitals' in- and outpatients and the environment. No isolate was resistant to cefoxitin by disk diffusion test and the corresponding resistance gene mecA was not found. In contrast, the resistance rates of SA to penicillin (63.6%) and trimethoprim-sulfamethoxazole (36.4%) and SP to penicillin (52.1%) and tetracycline (25.0%) were the highest. A variety of sequence types (STs) without a predominant type including numerous novel types were determined, especially for SP (39.6%). The spa typing provided a clonal assignment for all SAs (100%) and 24 SPs (50%) with three and two novel types, respectively. This study has provided an overview of SA and SP in the veterinary teaching hospital at UNZA. However, for a better understanding of these species regarding pathogenesis and transmission, further studies on the prevalence and characterization of SA and SP from veterinary staff, pet owners, and farm animals in Zambia is needed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. [Identification of plasmid-encoded cephalosporinase ACC-1 among various enterobacteria (Klebsiella pneumoniae, Proteus mirabilis, Salmonella) isolated from a Tunisian hospital (Sfax 997-2000)].

    Science.gov (United States)

    Rhimi-Mahjoubi, F; Bernier, M; Arlet, G; Jemaa, Z Ben; Jouve, P; Hammami, A; Philippon, A

    2002-02-01

    Because a multiresistant K. pneumoniae outbreak detected in an intensive care unit of a parisian hospital, combined to the production of the plasmid-encoded cephalosporinase ACC-1, a probable importation via a patient was suggested from another country (Tunisia). The investigation was conducted to examine 35 clinical strains of enterobacteria resistant to ceftazidime without synergy towards Augmentin. Other test of synergy with two inhibitors, BRL 42715, Ro 48-5545 was performed by diffusion method and deposit of 10 micrograms of inhibitor on disks containing ceftazidime, cefoxitin and cefotetan. Synergies were obtained suggesting a probable production of ACC-1 type among six isolates of K. pneumoniae (two), Proteus mirabilis (one) and Salmonella (three) issued from different units. The isoelectric focusing on gel revealed at least one band of beta-lactamase activity at 7.8 but also demonstrated the simultaneous production of several probable beta-lactamases including TEM-type, SHV-2 and ACC-1 among S. enterica ser. Livingstone. The PCR of the gene blaacc-1 was positive. The sequencing (1160 pb) of two products showed high identity (99-100%) with the gene blaacc-1 deposited in 1999. Finally the ACC-1 type reported in Tunisia was probably imported in France via a patient. Because a simultaneous synthesis of ESBL and ACC-1 type, its presence may be invisible and need more investigation.

  2. Bacteriological and virulence study of a Mycobacterium chimaera isolate from a patient in China.

    Science.gov (United States)

    Liu, Guan; Chen, Su-Ting; Yu, Xia; Li, Yu-Xun; Ling, Ying; Dong, Ling-Ling; Zheng, Su-Hua; Huang, Hai-Rong

    2015-04-01

    A clinical isolate from a patient was identified as Mycobacterium chimaera, a recently identified species of nontuberculous Mycobacteria. The biochemical and molecular identity, drug sensitivity and virulence of this isolated strain were investigated. 16S rRNA, the 16S-23S ITS, hsp65 and rpoB were amplified, and their sequence similarities with other mycobacteria were analyzed. The minimum inhibitory concentrations of 22 anti-microbial agents against this isolate were established, and the virulence of the isolate was evaluated by intravenous injection into C57BL/6 mice using Mycobacterium tuberculosis H37Rv as a control strain. Growth and morphological characteristics and mycolic acid profile analysis revealed that this isolated strain was a member of the Mycobacterium avium complex. BLAST analysis of the amplified sequences showed that the isolated strain was closely related to M. chimaera. Susceptibility testing showed that the isolate was sensitive to rifabutin, rifapentine, clarithromycin, azithromycin, imipenem and cefoxitin. Bacterial load determination and tissue histopathology of the infected mice indicated that the isolate was highly virulent. The first case of M. chimaera infection in China was evaluated. The information derived from this case may offer valuable guidance for clinical diagnosis and treatment.

  3. Impairments of mecA gene detection in bovine Staphylococcus spp.

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    Dayanne Araújo de Melo

    2014-09-01

    Full Text Available Staphylococcus aureus antimicrobial resistance, especially to beta-lactams, favors treatment failures and its persistence in herd environment. This work aimed to develop a more specific primer for mecA gene detection based on the comparison of the conserved regions from distinct host origins and also investigated the presence of homologue mecA LGA251 in bovine strains. A total of 43 Staphylococcus spp. were included in this study, comprising 38 bovine S. aureus, two human and three equine coagulase-negative staphylococci (CNS. Phenotypical methicillin-resistance detection was performed through oxacillin agar-screening and cefoxitin disk-diffusion test. None isolate tested positive for mecA LGA251 gene. For mecA gene PCR, new primers were designed based on the sequences of human S. aureus (HE681097 and bovine S. sciuri (AY820253 mecA. The new primers based on the S. aureus mecA sequence amplified fragments of human and equine CNS and the ones based on S. sciuri mecA sequence only yielded fragments for S. aureus bovine strains. Multiples alignments of mecA gene sequences from bovine, human and equine revealed punctual but significant differences in bovine strains that can lead to the mecA gene detection impairment. The observed divergences of mecA gene sequences are not a matter of animal or human origin, it is a specificity of bovine samples.

  4. Evaluation of probiotic potential of lactic acid bacteria to reduce in vitro cholesterol

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    Clementina Cueto

    2012-03-01

    Full Text Available Daily consumption of probiotics reduce levels of serum cholesterol by up to 3%, which is significant to prevent hypercholesterolemia, a risk factor for cardiovascular disease and cause of mortality. The genus Lactobacillus is used in industry as a probiotic and some species reduce serum cholesterol by two mechanisms, the adsorption of cholesterol and the production of the enzyme bile salt hydrolase, which vary according to species. The aim of the study was to assess the ability of probiotic bacteria group isolated from coast serum. 53 strains were isolated from nine coastal serum sample; the sensitivity to cefoxitin and vancomycin, and the tolerance to pH 2.0 and 0.3% bile salts were evaluated to determine its probiotic potential. Five microorganisms were selected and molecularly identified as Lactobacillus fermentum. The ability to absorb cholesterol measured by the method of Kimoto, showed a reduction of 53.06 ± 2.69 µg.mL-1 for strain K73 and 7.23 ± 2.69 µg. mL-1 for K75. These same strains showed the highest total and specific activity of the enzyme. The results didn´t show a relationship between the production of enzyme and adsorption of cholesterol. The strain with the greatest probiotic potential was K73. This hypocholesterolemic property will give strains added value to start the search for food matrices that allow decreasing serum cholesterol levels.

  5. 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)

  6. High-dose antibiotic therapy is superior to a 3-drug combination of prostanoids and lipid A derivative in protecting irradiated canines

    International Nuclear Information System (INIS)

    Kumar, K.S.; Srinivasan, V.; Toles, R.E.; Miner, V.L.; Jackson, W.E.; Seed, T.M.

    2002-01-01

    There is an urgent need to develop non-toxic radioprotectors. We tested the efficacy of a 3-drug combination (3-DC) of iloprost, misoprostol, and 3D-MPL (3-deacylated monophosphoryl lipid A) and the effects of postirradiation clinical support with high doses of antibiotics and blood transfusion. Canines were given 3-DC or the vehicle and exposed to 3.4 Gy or 4.1 Gy of 60 Co radiation. Canines irradiated at 4.1 Gy were also given clinical support, which consisted of blood transfusion and antibiotics (gentamicin, and cefoxitin or cephalexin). Peripheral blood cell profile and 60-day survival were used as indices of protection. At 3.4 Gy, 3-DC- or vehicle-treated canines without postirradiation clinical support survived only for 10 to 12 days. Fifty percent of the canines treated with 3-DC or vehicle and provided postirradiation clinical support survived 4.1-Gy irradiation. Survival of canines treated with vehicle before irradiation significantly correlated with postirradiation antibiotic treatments, but not with blood transfusion. The recovery profile of peripheral blood cells in 4.1 Gy-irradiated canines treated with vehicle and antibiotics was better than drug-treated canines. These results indicate that therapy with high doses of intramuscular aminoglycoside antibiotic (gentamicin) and an oral cephalosporin (cephalexin) enhanced survival of irradiated canines. Although blood transfusion correlated with survival of 3-DC treated canines, there were no additional survivors with 3-DC treated canines than the controls. (author)

  7. Nasal carriage of Methicillin-resistant Staphylococcus aureus among healthy population of Kashmir, India

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    B A Fomda

    2014-01-01

    Full Text Available Background: Nasal colonisation with community acquired methicillin resistant Staphylococcus aureus (CA-MRSA is being increasingly reported, especially in places where people are in close contact and where hygiene is compromised. The aim of this study was to find out prevalence of methicillin resistant S.aureus (MRSA colonising anterior nares of healthy subjects. Materials and Methods: Nasal swabs of healthy subjects were collected aseptically and cultured using standard microbiological protocols. Antibiotic susceptibility was done by Kirby-Bauer disc diffusion method according to CLSI guidelines. Methicillin resistance was detected by cefoxitin disc diffusion method and confirmed by minimum inhibitory concentration (MIC and amplification of mecA gene by PCR. Strain typing of MRSA strains was done by PFGE. Results: Out of 820 samples, S.aureus was isolated from 229 (27.92% subjects. Of the 229 isolates, 15 were methicillin resistant. All S. aureus isolates were susceptible to vancomycin. Nasal carriage of MRSA was found to be 1.83% among healthy population. The isolates were found to be polyclonal by PFGE analysis. Conclusion: High prevalence of MRSA is a cause of concern and strategies to interrupt transmission should be implemented.

  8. Prevalence of Bacterial Vaginosis and Associated Risk Factors among Women Complaining of Genital Tract Infection

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    Adane Bitew

    2017-01-01

    Full Text Available Background. Bacterial vaginosis is a global concern due to the increased risk of acquisition of sexually transmitted infections. Objectives. To determine the prevalence of bacterial vaginosis and bacteria causing aerobic vaginitis. Methods. A cross-sectional study was conducted among 210 patients between September 2015 and July 2016 at St. Paul’s Hospital. Gram-stained vaginal swabs were examined microscopically and graded as per Nugent’s procedure. Bacteria causing aerobic vaginitis were characterized, and their antimicrobial susceptibility pattern was determined. Results. The overall prevalence of bacterial vaginosis was 48.6%. Bacterial vaginosis was significantly associated with number of pants used per day (p=0.001 and frequency of vaginal bathing (p=0.045. Of 151 bacterial isolates, 69.5% were Gram-negative and 30.5% were Gram-positive bacteria. The overall drug resistance level of Gram-positive bacteria was high against penicillin, tetracycline, and erythromycin. Cefoxitin and tobramycin were the most active drugs against Gram-positive bacteria. The overall drug resistance level of Gram-negative bacteria was high against tetracycline, ampicillin, and amoxicillin. Amikacin and tobramycin were the most active drugs against Gram-negative bacteria. Conclusions. The prevalence of bacterial vaginosis was high and was affected by individual hygiene. Routine culture of vaginal samples should be performed on patients with vaginitis and the drug susceptibility pattern of each isolate should be determined.

  9. Report of two fatal cases of Mycobacterium mucogenicum central nervous system infection in immunocompetent patients.

    Science.gov (United States)

    Adékambi, Toïdi; Foucault, Cedric; La Scola, Bernard; Drancourt, Michel

    2006-03-01

    Neurological infections due to rapidly growing mycobacteria (RGM) have rarely been reported. We recently investigated two unrelated immunocompetent patients, one with community-acquired lymphocytic meningitis and the other with cerebral thrombophlebitis. Mycobacterium mucogenicum was isolated in pure culture and detected by PCR sequencing of cerebrospinal fluid samples. Both patients eventually died. The two isolates exhibited an overlapping antimicrobial susceptibility pattern. They were susceptible in vitro to tetracyclines, macrolides, quinolones, amikacin, imipenem, cefoxitin, and trimethoprim-sulfamethoxazole and resistant to ceftriaxone. They shared 100% 16S rRNA gene sequence similarity with M. mucogenicum ATCC 49650T over 1,482 bp. Their partial rpoB sequences shared 97.8% and 98.1% similarity with M. mucogenicum ATCC 49650T, suggesting that the two isolates were representative of two sequevars of M. mucogenicum species. This case report should make clinicians aware that M. mucogenicum, an RGM frequently isolated from tap water or from respiratory specimens and mostly without clinical significance, can even be encountered in the central nervous system of immunocompetent patients.

  10. Mycoplasma genitalium: An Emerging Cause of Pelvic Inflammatory Disease

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    Catherine L. Haggerty

    2011-01-01

    Full Text Available Mycoplasma genitalium is a sexually transmitted pathogen that is increasingly identified among women with pelvic inflammatory disease (PID. Although Chlamydia trachomatis and Neisseria gonorrhoeae frequently cause PID, up to 70% of cases have an unidentified etiology. This paper summarizes evidence linking M. genitalium to PID and its long-term reproductive sequelae. Several PCR studies have demonstrated that M. genitalium is associated with PID, independent of gonococcal and chlamydial infection. Most have been cross-sectional, although one prospective investigation suggested that M. genitalium was associated with over a thirteenfold risk of endometritis. Further, a nested case-control posttermination study demonstrated a sixfold increased risk of PID among M. genitalium positive patients. Whether or not M. genitalium upper genital tract infection results in long-term reproductive morbidity is unclear, although tubal factor infertility patients have been found to have elevated M. genitalium antibodies. Several lines of evidence suggest that M. genitalium is likely resistant to many frequently used PID treatment regimens. Correspondingly, M. genitalium has been associated with treatment failure following cefoxitin and doxycycline treatment for clinically suspected PID. Collectively, strong evidence suggests that M. genitalium is associated with PID. Further study of M. genitalium upper genital tract infection diagnosis, treatment and long-term sequelae is warranted.

  11. Clinical and microbiological characterization of Staphylococcus lugdunensis isolates obtained from clinical specimens in a hospital in China

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    Liu Chaojun

    2012-08-01

    Full Text Available Abstract Background Several reports have associated Staphylococcus lugdunensis with the incidence of severe infection in humans; however, the frequency and prevalence of this microorganism and thus the propensity of its antimicrobial drug resistance is unknown in China. The objective of the current study was to determine the prevalence of Staphylococcus lugdunensis among six hundred and seventy non-replicate coagulase negative Staphylococcus (CoNS isolates collected in a 12-month period from clinical specimens in the General Hospital of the People’s Liberation Army in Beijing, China. Results Five (0.7% of the 670 isolates of CoNS were identified as S. lugdunensis. Whereas three isolates were resistant to erythromycin, clindamycin, and penicillin and carried the ermC gene and a fourth one was resistant to cefoxitin and penicillin and carried the mecA gene, one isolate was not resistant to any of the tested antimicrobials. Pulse field gel electrophoretic analysis did not reveal widespread epidemiological diversity of the different isolates. Conclusion Hence, even though S. lugdunensis may be yet unrecognized and undefined in China, it still might be the infrequent cause of infection and profound multi-drug resistance in the same population.

  12. Beta-lactamases production and antimicrobial resistance ratio of Pseudomonas aeruginosa from hospitalized patients in Kahramanmaras, Turkey.

    Science.gov (United States)

    Toroglu, Sevil; Avan, Hatice; Keskin, Dilek

    2013-07-01

    Sixteen isolates of P. aeruginosa were collected from different hospitals in Kahramanmaras among 2006-2007 and tested for the level of resistance to the widely used antipseudomonal antibiotics and used in local midicinal and veterinary practice. The aim of this study was to determine the antibiotic resistance to P. aeruginosa strains isolated in Microbiology Laboratory of different hospitals in Kahramanmaras between 2006-2007. These strains were mostly isolated from urine and few from tracheolaringeal aspirate, tracheal secretion, mucus, bronchoalveolar lavage. The antibiotic resistance rates were as follows: Penicillin (PEN) 100%, Amoxicillin (AMO) 94%, Cefazolin (CEF) 87.5%, Cefoxitin (CEFX) 81%, Nitrofrantoin (NIT) 75%, Chlorampenicol (CHL) 62.5%, Tetracycline (TET) 56%, Ceftriaxone (CEFT) 44%, Oflaxain (OFL) and Gentamycin (GEN) 37.5%, Meropenem (MER) and Streptomycine (STR) 31%. Among 16 isolates of P. aeruginosa from wounds showed 8 (50%) beta-lactamase activity, whereas 8 isolates of P. aeruginosa from urine showed no beta-lactamase activity. All P. aeruginosa strains 16 (100%) isolates showed multiple antibiotic resistance towards three to eleven antibiotics.

  13. CHARACTERIZATION OF EXTENDED-SPECTRUM Β-LACTAMASE-PRODUCING ESCHERICHIA COLI STRAINS ISOLATED FROM DAIRY PRODUCTS

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    Rahem Khoshbakht

    2014-02-01

    Full Text Available Extended-spectrum β-lactamases (ESBLs are enzymes that hydrolyze the β-lactam ring, and ESBL-producing E. coli has rapidly spread worldwide with pose a serious hazard for humans. The aim of this study was to determine the prevalence of ESBL producing E. coli and molecular evaluation of four ESBL-associated genes among E. coli strains isolated from milk and cheese in southern Iran. Antibiotic susceptibility test was carried out for a total of 150 isolates of E. coli, previously collected from dairy products. ESBL production was screened using a double-disc synergy test (DDST and presence of four ESBL genes (PER, VEB, TEM and CTX-M was tested using PCR. Among 150 E. coli strains 57 (38% isolates were identified as ESBL-producing strains. All ESBL positive isolates could be typed for one or more genes and the most prevalent ESBL-associated gene was CTX-M (80.7%. The PER gene was not present among isolates. Isolates showed high susceptibility to imipe¬nem and cefoxitin. The results showed the high prevalence of ESBL producing E. coli strains among dairy products and high occurrence of CTX-M-associated ESBL activity among isolates indicating the hazards of increasing the strains with antibiotic resistance which can transfer to human trough the dairy food products.

  14. The Incidence of Nosocomial Toxigenic Clostridium difficile Associated Diarrhea in Tehran Tertiary Medical Centers

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    Norakhoda Sadeghifard

    2010-10-01

    Full Text Available Clostridium difficile is the most common cause of nosocomial diarrhea. It is usually a consequence of antibiotic treatment, But sporadic cases can occur. This study was aimed to determine the frequency of the nosocomial Clostridium difficile (C. difficile associated diarrhea in Tehran University of Medical Sciences hospitals and study of antibacterial susceptibility of isolates. In this study a total of 942 stool samples from patients with nosocomial diarrhea that were hospitalized in Imam Khomeini hospital, Shariati hospital and Children clinical center were collected. The samples were cultured on a selective cycloserine cefoxitin fructose agar (CCFA and incubated in anaerobic conditions, at 37°C for 5 days. Isolates were characterized to species level by conventional biochemical tests. Bacterial cytotoxicity was assayed on tissue culture (vero. Antimicrobial sensitivity of isolated toxigenic C. difficile were investigated by kirby Beuer method (disk diffusion. Our findings show that, of the total patients, 57 toxigenic C. difficile (6.1% were isolated. Results of statistical analysis show significant differences between the rate of isolated toxigenic C. difficile and age group of patients (P

  15. Antibacterial Activity of Protocatechuic Acid Ethyl Ester on Staphylococcus aureus Clinical Strains Alone and in Combination with Antistaphylococcal Drugs

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    Maria Miklasińska

    2015-07-01

    Full Text Available The aim of the presented study was to examine in vitro the antibacterial activity of protocatechuic acid ethyl ester (ethyl 3,4-dihydroxybenzoate, EDHB against Staphylococcus aureus clinical isolates alone and in the combination with four selected antibiotics. The EDHB antimicrobial activity was tested against twenty S. aureus strains isolated from the clinical samples, and three reference strains. The phenotypes and genotypes of resistance to methicillin for the tested strains were defined as well as the phenotypic resistance to macrolides, lincosamides and streptogramin B (MLSB. EDHB displayed diverse activity against examined S. aureus strains with the minimal inhibitory concentration (MIC within the range from 64 to 1024 µg/mL. Addition of ¼ MIC of EDHB into the Mueller-Hinton Agar (MHA resulted in augmented antibacterial effect in the presence of clindamycin. In the case of cefoxitin no synergistic effect with EDHB was noted. For erythromycin and vancomycin the decrease of mean MICs in the presence of EDHB was observed but did not reach statistical significance. The results of the present study showed that in vitro EDHB possesses antibacterial activity against S. aureus clinical strains and triggers a synergistic antimicrobial effect with clindamycin and to the lesser extent with erythromycin and vancomycin.

  16. The prevalence of ESBL-producing E-coli and Klebsiella strains in the Copenhagen area of Denmark

    DEFF Research Database (Denmark)

    Kjerulf, A.; Hansen, D.S.; Sandvang, D.

    2008-01-01

    The main purpose of the study was to investigate the frequency of ESBL-producing E. coli and Klebsiella strains in the Greater Copenhagen area. Four collections of strains were investigated: A) 380 consecutive E. coli and Klebsiella isolates primarily from urine, B) 200 gentamicin-resistant E. coli...... confirmatory test for ESBL production and all screening test-positive strains were examined with PCR and nucleotide sequencing in order to detect the following ESBL genes: ctx-m, shv, tem and oxa. Strains resistant to cefoxitin were further examined with cefotetan +/- boronic acid in order to detect Amp......C. An ESBL gene was detected in 3/3 confirmatory test-positive isolates from collection A, in 14/17 from collection B, and in 41/48 from collection D. The distribution of isolates with the ESBL and/or AmpC enzymes was as follows: CTX-M (n=41), SHV (n=14), AmpC (n=9), CTX-M and AmpC (n=2), SHV and AmpC (n=1...

  17. Antimicrobial resistance trends among Salmonella isolates obtained from horses in the northeastern United States (2001-2013).

    Science.gov (United States)

    Cummings, Kevin J; Perkins, Gillian A; Khatibzadeh, Sarah M; Warnick, Lorin D; Aprea, Victor A; Altier, Craig

    2016-05-01

    OBJECTIVE To describe the antimicrobial resistance patterns of Salmonella isolates obtained from horses in the northeastern United States and to identify trends in resistance to select antimicrobials over time. SAMPLE 462 Salmonella isolates from horses. PROCEDURES Retrospective data were collected for all Salmonella isolates obtained from equine specimens that were submitted to the Cornell University Animal Health Diagnostic Center between January 1, 2001, and December 31, 2013. Temporal trends in the prevalence of resistant Salmonella isolates were investigated for each of 13 antimicrobials by use of the Cochran-Armitage trend test. RESULTS The prevalence of resistant isolates varied among antimicrobials and ranged from 0% (imipenem) to 51.5% (chloramphenicol). During the observation period, the prevalence of resistant isolates decreased significantly for amoxicillin-clavulanic acid, ampicillin, cefazolin, cefoxitin, ceftiofur, chloramphenicol, and tetracycline and remained negligible for amikacin and enrofloxacin. Of the 337 isolates for which the susceptibility to all 13 antimicrobials was determined, 138 (40.9%) were pansusceptible and 192 (57.0%) were multidrug resistant (resistant to ≥ 3 antimicrobial classes). The most common serovar isolated was Salmonella Newport, and although the annual prevalence of that serovar decreased significantly over time, that decrease had only a minimal effect on the observed antimicrobial resistance trends. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that current antimicrobial use in horses is not promoting the emergence and dissemination of antimicrobial-resistant Salmonella strains in the region served by the laboratory.

  18. Genotypic relatedness and antimicrobial resistance of Salmonella Heidelberg isolated from chickens and turkeys in the midwestern United States.

    Science.gov (United States)

    Nisar, Muhammad; Kassem, Issmat I; Rajashekara, Gireesh; Goyal, Sagar M; Lauer, Dale; Voss, Shauna; Nagaraja, Kakambi V

    2017-05-01

    Salmonella is one of the most common causes of foodborne illnesses in humans in the United States, and domestic poultry is considered an important source of this pathogen. Salmonella enterica subsp. enterica serovar Heidelberg is the fourth most commonly reported Salmonella from retail meats and food animals in the United States. We assessed the genotypes and antimicrobial resistance phenotypes of Salmonella Heidelberg isolated from various chicken and turkey hatcheries and breeder farms in the Midwest. The genotypes of 33 S. Heidelberg isolates from chickens ( n = 19) and turkeys ( n = 14) were compared using pulsed-field gel electrophoresis analysis. Cluster analysis of the fingerprints showed that the majority of the chicken isolates grouped together with 87% similarity; those from turkeys clustered with 88% similarity. Similarity between chicken and turkey isolates was also high (86%). Isolates from turkeys were generally more genetically diverse than those from chickens. Antimicrobial susceptibility analysis detected resistance to sulfisoxazole (36% of the isolates), streptomycin (33%), gentamicin (27%), tetracycline (24%), ampicillin and amoxicillin-clavulanic acid (15%), cefoxitin (12%), ceftriaxone and ceftiofur (12%), and chloramphenicol (9%). None of the isolates was resistant to azithromycin, ciprofloxacin, or nalidixic acid. Although the number of the isolates was limited in our study, we conclude that S. Heidelberg isolates from the same host generally clustered together and that a considerable number of the isolates were resistant to a number of antimicrobial agents.

  19. Mutant Prevention Concentrations of Imipenem and Meropenem against Pseudomonas aeruginosa and Acinetobacter baumannii

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    E. Dahdouh

    2014-01-01

    Full Text Available The aim of this study was to determine the usefulness of the MPC of carbapenems against clinical isolates of Pseudomonas spp. and Acinetobacter spp. and to assess its possible relationship with mechanisms of resistance. Detection of the mechanisms of resistance was performed using Antibiotic Susceptibility Testing, Double Disk Synergy, disk antagonism, addition of NaCl to the medium, addition of PBA or EDTA to Carbapenem disks, addition of PBA to Cefoxitin disks, and CCCP test for 10 Pseudomonas spp. and Acinetobacter baumannii strains. The MIC and MPC were determined using the broth macrodilution and plate dilution methods, respectively. Four Acinetobacter baumannii strains produced MBL. Two of them produced Oxacillinase and one produced ESBL. Two Pseudomonas spp. isolates produced both KPC and MBL. The resistant Acinetobacter spp. and Pseudomonas spp. strains had higher MPC values than susceptible ones. However, the Mutant Selection Window was found to be dependent on the degree of resistance but not on a particular mechanism of resistance. The usefulness of the MPC was found to be dependent on its value. Based on our data, we recommend determining the MPC for each isolate before using it during treatment. Furthermore, the use of T>MSW instead of T>MIC is suggested.

  20. Antimicrobial resistance profile of Methicillin-resistant Staphylococcus aureus colonizing the anterior nares of health-care workers and outpatients attending the remotely located tertiary care hospital of North India

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    Seema Singh

    2017-01-01

    Aims and Objectives: To determine the prevalence of MRSA colonisation, two hundred HCWs and 200 consecutive outpatients attending our tertiary care hospital were studied. Material and Methods: Two sterile pre-moistened cotton tipped swabs were used to collect specimens from their anterior nares. These were inoculated immediately on Blood agar with oxacillin, Mannitol salt agar with oxacillin and CHROM agar. Resistance to cefoxitin was confirmed by PCR by demonstration of mecA gene. Antibiotic susceptibility was determined by Kirby Bauer's disc diffusion method and MIC of vancomycin by using broth dilution and Vitek-2 Compact system. Results: The nasal carriage of MRSA among HCWs was found to be 7.5% and in outpatients 3%. All strains of MRSA from HCWs and outpatients grew on three selective media and mecA gene amplified in all of them. All the isolated strains of MRSA showed high degree of resistance to co-trimoxazole (93.3%, ciprofloxacin (80% and erythromycin (66.66%. However, there was 100% susceptiability to vancomycin, teicoplanin, linezolid and Rifampicin. Conclusion: Although a direct casual relationship could not be established, it could be assumed that the transmission from colonised health care worker is responsible atleast in part for MRSA infection among patients. Therefore emphasis should be laid on strict implementation of standard infection control practices which would help in minimizing the carriage and transmission of MRSA in the hospital.

  1. The antimicrobial susceptibility profile of ESKAPE pathogens from urinary tract infections in a referral laboratory, Northeast Iran

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    Mohammad Salehi

    2016-11-01

    Full Text Available Objective: To assess the antimicrobial susceptibility pattern of ESKAPE pathogens from Neyshabur, Iran during 2013–2015. Methods: A total of 345 isolates including 62 Staphylococcus aureus (S. aureus, 38 Enterobacter spp. (including 14 Enterobacter agglomerans, 6 Enterobacter aerogenes and other 18 Enterobacter spp., 123 Enterococcus faecium, 78 Klebsiella pneumonia, 10 Pseudomonas aeruginosa and 34 Acinetobacter baumannii were isolated. The antimicrobial susceptibility pattern of isolates was conducted with Kirby Bauer method. Data were analyzed with SPSS 20.0 software using F- and t-tests. Results: Among S. aureus isolates, the highest resistance was observed against nalidixic acid (81.35% and cefixime (74.50%. Thirty-three (53.22% S. aureus isolates were cefoxitin resistant (methicillin-resistant S. aureus. The majority of Enterobacter species was resistant to amikacin (100.00% and cephalotin (66.60%. Most Enterococcus faecium isolates were resistant to nalidixic acid (89.43% and amikacin (83.33%, but vancomycin-resistant enterococci isolates were not detected. Moreover, among Klebsiella pneumonia, the highest resistance was observed to nalidixic acid (20.98% and cotrimoxazole (28.39%. Furthermore, all Pseudomonas aeruginosa isolates were resistant to cefotaxime (100.00% and majority to nitroforantoin (88.80%. Acinetobacter baumannii isolates showed the highest and the lowest resistance to cefotaxime (100.00% and cefixime (88.71%, respectively. Conclusions: The prevalence of ESKAPE pathogens from northeast region was low, but majority of them exhibited high rate of antibiotic resistance to common used antimicrobial agents.

  2. High-dose antibiotic therapy is superior to a 3-drug combination of prostanoids and lipid A derivative in protecting irradiated canines

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, K.S.; Srinivasan, V.; Toles, R.E.; Miner, V.L.; Jackson, W.E.; Seed, T.M. [Armed Forces Radiobiology Research Inst., Bethesda, MD (United States)

    2002-12-01

    There is an urgent need to develop non-toxic radioprotectors. We tested the efficacy of a 3-drug combination (3-DC) of iloprost, misoprostol, and 3D-MPL (3-deacylated monophosphoryl lipid A) and the effects of postirradiation clinical support with high doses of antibiotics and blood transfusion. Canines were given 3-DC or the vehicle and exposed to 3.4 Gy or 4.1 Gy of {sup 60}Co radiation. Canines irradiated at 4.1 Gy were also given clinical support, which consisted of blood transfusion and antibiotics (gentamicin, and cefoxitin or cephalexin). Peripheral blood cell profile and 60-day survival were used as indices of protection. At 3.4 Gy, 3-DC- or vehicle-treated canines without postirradiation clinical support survived only for 10 to 12 days. Fifty percent of the canines treated with 3-DC or vehicle and provided postirradiation clinical support survived 4.1-Gy irradiation. Survival of canines treated with vehicle before irradiation significantly correlated with postirradiation antibiotic treatments, but not with blood transfusion. The recovery profile of peripheral blood cells in 4.1 Gy-irradiated canines treated with vehicle and antibiotics was better than drug-treated canines. These results indicate that therapy with high doses of intramuscular aminoglycoside antibiotic (gentamicin) and an oral cephalosporin (cephalexin) enhanced survival of irradiated canines. Although blood transfusion correlated with survival of 3-DC treated canines, there were no additional survivors with 3-DC treated canines than the controls. (author)

  3. Prevalence and Characterization of Cronobacter sakazakii in Retail Milk-Based Infant and Baby Foods in Shaanxi, China.

    Science.gov (United States)

    Li, Zhen; Ge, Wupeng; Li, Keting; Gan, Jing; Zhang, Yifan; Zhang, Qiang; Luo, Rong; Chen, Limin; Liang, Yi; Wang, Qianning; Xi, Meili; Xia, Xiaodong; Wang, Xin; Yang, Baowei

    2016-04-01

    Cronobacter sakazakii (formerly Enterobacter sakazakii) is an opportunistic pathogen that causes meningitis, sepsis, and necrotizing enterocolitis in neonates and infants through consumption of contaminated milk-based foods. In this study, the prevalence of C. sakazakii in 705 retail milk-based infant and baby food samples was investigated in 12 cities in Shaanxi, China, in 2010 and 2012. One hundred and nineteen samples (16.9%) were C. sakazakii positive. The isolates were further characterized for antimicrobial susceptibility to 14 antibiotics, pulsed-field gel electrophoresis profiles, and presence of the virulence genes. Samples of brand W, Y, A, and G in 2010 and 2012 were C. sakazakii positive. All isolates recovered in 2010 and 2012 were susceptible to levofloxacin and cefoperazone. In 2012, no isolate was resistant to gentamicin, cefoxitin, chloramphenicol, gatifloxacin, ciprofloxacin, and ceftriaxone. Antibiotic resistance of the isolates was most commonly found to rifampicin, amoxicillin-clavulanic acid, streptomycin, tetracycline, and ampicillin in both 2010 and 2012, except to trimethoprim/sulfamethoxazole in 2012. Pulsed-field gel electrophoresis profiles indicated that C. sakazakii isolates were genotypically diverse, although these isolates were prevalent in infant and baby foods with the same brand. A total of 34 virulence gene profiles of the C. sakazakii isolates in 2010 and 2012 were detected. Isolates that co-carried hly-ompX-eitCBAD-iucABCD/iutA genes in 2012 were significantly (p baby foods and this should be an indicator of potential health risk for consumers.

  4. Prevalence of Post-operative Wound Infections in Rural area of Latur District

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    Vikram Rajput

    2015-08-01

    Full Text Available Background: Surgical site infection (SSI continues to be a major source of morbidity following operative procedures. The modern surgeon cannot escape the responsibility of dealing with infections, having the knowledge for the appropriate use of aseptic and antiseptic technique, proper use of prophylactic and therapeutic antibiotics, and adequate monitoring and support with novel surgical and pharmacologic as well as nonpharmacologic aids. Objective: To study the most common organisms encountered in postoperative wound infections and to find out the most effective Antibiotics in case of Post Operative Wound Infections. Methodology: It is an Observational study done on 50 operated cases of post operative wounds. Results: Most common microorganism encountered in present series was E. coli in 13 cases (26%. Least common micro organism was Proteus (2%. E. coli was also encountered in mixed culture with Kleibsiella, Pseudomonas and Citrobacter. Most effective antibiotic in present series was Imipenem. Other common effective antibiotics were Amikacin, Netillin, Piperacillin, Tetracycline and Gentamycin. Least effective antibiotics were Penicillin, Cefotaxime, Cefuroxime and Cefoxitin. Conclusion: E. coli was the most common organism cultured. Imipenem and Amikacin were the most effective antibiotics.

  5. Heavy metal and antibiotic resistance in bacteria isolated from the environment of swine farms

    International Nuclear Information System (INIS)

    Fan, Y.; Ping, C.; Mei, L.S.

    2014-01-01

    The aim of the present study was to determine the level of heavy metal resistance and antibiotic resistance patterns of bacterial isolates from environment of swine farms in China. A total of 284 bacteria were isolated, 158 from manure, 62 from soil and 64 from wastewater in different swine farm samples. All the isolates were tested for resistant against eight heavy metals. From the total of 284 isolates, maximum bacterial isolates were found to be resistant to Zn/sup 2+/ (98.6%) followed by Cu/sup 2+/ (97.5%), Cd/sup 2+/ (68.3%), Mn/sup 2+/ (60.2%), Pb/sup 2+/(51.4%), Ni/sup 2+/(41.5%) and Cr/sup 2+/(45.1%). However, most of the isolates were sensitive to Co/sup 2+/. Meanwhile,all the isolates were tested for sensitively to nine antibiotics. The results shows that most isolates were sensitive to cefoxitin and oxacillin, but resistance to tetracycline, ampicillin, gentamicin, amikacin, erythromycin, clindamycin were widespread. Multiple resistant to metals and antibiotics were also observed in this study. Most isolates were tolerant to different concentrations of various heavy metals and antibiotics. Our results confirmed that environment of swine farms in China has a significant proportion of heavy metal and antibiotic resistant bacteria, and these bacteria constitute a potential risk for swine health and public health. (author)

  6. Variable selection in near infrared spectroscopy for quantitative models of homologous analogs of cephalosporins

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    Yan-Chun Feng

    2014-07-01

    Full Text Available Two universal spectral ranges (4550–4100 cm-1 and 6190–5510 cm-1 for construction of quantitative models of homologous analogs of cephalosporins were proposed by evaluating the performance of five spectral ranges and their combinations, using three data sets of cephalosporins for injection, i.e., cefuroxime sodium, ceftriaxone sodium and cefoperazone sodium. Subsequently, the proposed ranges were validated by using eight calibration sets of other homologous analogs of cephalosporins for injection, namely cefmenoxime hydrochloride, ceftezole sodium, cefmetazole, cefoxitin sodium, cefotaxime sodium, cefradine, cephazolin sodium and ceftizoxime sodium. All the constructed quantitative models for the eight kinds of cephalosporins using these universal ranges could fulfill the requirements for quick quantification. After that, competitive adaptive reweighted sampling (CARS algorithm and infrared (IR–near infrared (NIR two-dimensional (2D correlation spectral analysis were used to determine the scientific basis of these two spectral ranges as the universal regions for the construction of quantitative models of cephalosporins. The CARS algorithm demonstrated that the ranges of 4550–4100 cm-1 and 6190–5510 cm-1 included some key wavenumbers which could be attributed to content changes of cephalosporins. The IR–NIR 2D spectral analysis showed that certain wavenumbers in these two regions have strong correlations to the structures of those cephalosporins that were easy to degrade.

  7. Characterization of methicillin-resistant Staphylococcus spp. isolated from dogs in Korea.

    Science.gov (United States)

    Jang, Yunho; Bae, Dong hwa; Cho, Jae-Keun; Bahk, Gyung Jin; Lim, Suk-Kyung; Lee, Young Ju

    2014-11-01

    Staphylococci were isolated from dogs in animal hospitals, animal shelters, and the Daegu PET EXPO to investigate the characteristics of circulating methicillin-resistant Staphylococcal (MRS) strains in companion animals in Korea. A total of 36/157 isolates were classified as MRS, and subdivided as follows: 1 methicillin-resistant Staphylococcus aureus (MRSA), 4 methicillin-resistant Staphylococcus epidermidis, 2 methicillin-resistant Staphylococcus haemolyticus, and 29 MRS spp. Among the 36 MRS isolates tested, 100% were resistant to oxacillin and penicillin, and at least 50% were resistant to sulfamethoxazole/trimethoprim (69.4%), erythromycin (63.9%), tetracycline (58.3%), cefoxitin (55.6%), clindamycin (50.0%) or pirlimycin (50.0%). Additionally, 34/36 MRS isolates (94.4%) were mecA positive, 15 of which were further classified as SCCmec type V, 6 isolates as type I, 4 isolates as type IIIb, 1 isolate as type IVa, 1 isolate as type IV, with 7 isolates being non-classifiable. The results of multilocus sequence typing and spa typing for the one MRSA strain were ST 72 (1-4-1-8-4-4-3) and spa t148. Our results provide evidence that companion animals like dogs may be MRS carriers, and that continued surveillance of MRS in companion animals is required to prevent increased incidences in humans.

  8. Molecular Typing of Hospital-Acquired Staphylococcus aureus Isolated from Isfahan, Iran

    Science.gov (United States)

    Havaei, Seyed Asghar; Ghanbari, Fahimeh; Rastegari, Ali Asghar; Khademi, Farzad; Hosseini, Nafiseh; Ebrahimzadeh Namvar, Amirmorteza; Vaez, Hamid; Havaei, Seyed Mehdi; Shahin, Mojtaba

    2014-01-01

    Background. Staphylococcus aureus (S. aureus) is one of the most common pathogens that cause hospital- and community-acquired infections in the world. The use of molecular typing methods is essential for determining the origin of the strains, their clonal relations, and also in epidemiological investigations. The purpose of this study was to determine the prevalence of antibiotic resistant S. aureus isolates and using spa, agr, and SCCmec typing to determine the dominant types in Iran. Material and Method. Fifty isolates of S. aureus were collected from January to May 2010. S. aureus identification was performed by biochemical tests. Disk diffusion method was employed to assess the sensitivity of S. aureus strains to antibiotics and then genetic analysis of bacteria was performed using SCCmec, agr, and spa typing. Results. S. aureus resistance to tetracycline, cefoxitin, clindamycin, ciprofloxacin, gentamicin, Cot: cotrimoxazole, levofloxacin, rifampin, and vancomycin were found to be 36%, 18%, 12%, 12%, 22%, 6%, 6%, and 0%, respectively. The results of this study showed that 16% of the isolates were resistant to methicillin (MRSA) and the majority of isolates were SSC mec type IV. In addition spa and agr typing revealed agr typeI and spa type t7688 to be the most predominant. Conclusion. In this study, spa typing showed 100% reliability and the t7688 spa type had a frequency of 26% compared to the frequency of 0.0% in the Ridom SpaServer. The frequency of t304 spa type was higher than the global average. PMID:27350987

  9. Validation of the MicroScan-96 for the species identification and methicillin susceptibility testing of clinical significant coagulase-negative staphylococci.

    Science.gov (United States)

    Patteet, L; Goossens, H; Ieven, M

    2012-05-01

    An automated system, MicroScan WalkAway-96, in conjugation with Combo Pos® 28 panels, was validated for the identification and methicillin susceptibility of coagulase-negative staphylococci (CNS). The performance of this system was evaluated on 428 CNS. Identification results were compared using a validated in-house method. Methicillin susceptibility was compared with oxacillin MIC testing and the presence of the mecA gene by PCR (in-house real-time method). The MicroScan system correctly identified 94.6% of the staphylococci (405 out of 428). 3.5% of the strains (15 out of 428) were not correctly identified. 1.9% of the isolates (8 out of 428) were correctly identified with a low probability. Identification of Staphylococcus warneri and Staphylococcus lugdunensis was determined with the least accuracy. Microscan combines both oxacillin and cefoxitin for determination of the methicillin susceptibility result. Correlation between this result and the mecA method was 97.6%. Correlation with the oxacillin MIC method was also 97.6%. Fourteen isolates showed a discrepant result, 8 were reported to be resistant in mecA-negative strains, 2 were reported false-susceptible in mecA positive strains and 4 strains showed a discrepant result with oxacillin MIC, but not with mecA determination. The automated system can be considered a simple and reliable method for identification and methicillin susceptibility of CNS.

  10. ESBL-producing Enterobacteriaceae: occurrence, risk factors for fecal carriage and strain traits in the Swiss slaughter cattle population younger than 2 years sampled at abattoir level.

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    Martin Reist

    Full Text Available During the past decade extended-spectrum beta-lactamase (ESBL producing Enterobacteriaceae have become a matter of great concern in human and veterinary medicine. In this cross-sectional study fecal swabs of a geographically representative number of Swiss cattle at slaughterhouse level were sampled i to determine the occurrence of ESBL producing Enterobacteriaceae in the Swiss slaughter cattle population younger than 2 years, and ii to assess risk factors for shedding ESBL producing Enterobacteriaceae. In total, 48 (8.4%; 95% C.I. 6.3-11.1% independent ESBL producing Enterobacteriaceae were detected among the 571 tested animals. Species identification revealed 46 E. coli strains, one Enterobacter cloacae and one Citrobacter youngae. In view of beta-lactam antibiotics, all 48 isolates were resistant to ampicillin, cephalothin and cefpodoxime. Forty-five (93.8% isolates were resistant cefuroxime; one (2.1% isolate to cefoxitin, 28 (58.3% isolates to cefotaxime, 2 (4.2% isolates to ceftazidime, and 2 (4.2% isolates to cefepime. Risk factors for shedding ESBL producing Enterobacteriaceae were (i age (OR 0.19 and 0.12 in age category 181 d to 1 y and 1 y to 2 y compared to ≤180 d, (ii primary production type, meaning dairy compared to beef on farm of origin (OR 5.95, and (iii more than 1 compared to less than 1 animal movement per d per 100 animals on farm of origin (OR 2.37.

  11. Staphylococcus pseudintermedius and Staphylococcus schleiferi Subspecies coagulans from Canine Pyoderma Cases in Grenada, West Indies, and Their Susceptibility to Beta-Lactam Drugs

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    Harry Hariharan

    2014-01-01

    Full Text Available Over a 2-year period 66 cases of canine pyoderma in Grenada, West Indies, were examined by aerobic culture in order to ascertain the bacteria involved and their antimicrobial resistance patterns. Of the 116 total bacterial isolates obtained, the majority belonged to Gram-positive species, and the most common organism identified through biochemical and molecular methods was Staphylococcus pseudintermedius. Additionally, identification of a Staphylococcus schleiferi subspecies coagulans isolate was confirmed by molecular methods. All isolates of staphylococci were susceptible to beta-lactam drugs: amoxicillin-clavulanic acid, cefovecin, cefoxitin, cefpodoxime, and cephalothin. They were also susceptible to chloramphenicol and enrofloxacin. Resistance was highest to tetracycline. Methicillin resistance was not detected in any isolate of S. pseudintermedius or in S. schleiferi. Among the Gram-negative bacteria, the most common species was Klebsiella pneumoniae, followed by Acinetobacter baumannii/calcoaceticus. The only drug to which all Gram-negative isolates were susceptible was enrofloxacin. This report is the first to confirm the presence of S. pseudintermedius and S. schleiferi subspecies coagulans, in dogs with pyoderma in Grenada, and the susceptibility of staphylococcal isolates to the majority of beta-lactam drugs used in veterinary practice.

  12. Emerging threat of multidrug resistant bugs--Acinetobacter calcoaceticus baumannii complex and methicillin resistant Staphylococcus aureus.

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    Mishra, Shyam Kumar; Rijal, Basista Prasad; Pokhrel, Bharat Mani

    2013-03-15

    Infections caused by bacteria such as multidrug resistant (MDR) Acinetobacter spp. and methicillin-resistant Staphylococcus aureus (MRSA) constitute a worldwide pandemic. Without gathering information about these strains, we cannot reduce the morbidity and mortality due to infections caused by these notorious bugs. This study was conducted to identify the status of MDR Acinetobacter spp. and MRSA in a tertiary care centre of Nepal. Sputum, endotracheal aspirate and bronchial washing specimens were collected and processed from patients suspected of lower respiratory tract infection following standard microbiological methods recommended by the American Society for Microbiology (ASM). Double disk synergy test method was employed for the detection of extended-spectrum beta-lactamase (ESBL) in Acinetobacter isolates. Methicillin resistance in S. aureus was confirmed by using cefoxitin and oxacillin disks. Different genomespecies of Acinetobacter were isolated; these consisted of Acinetobacter calcoaceticus baumannii complex and A. lwoffii. Around 95% of Acinetobacter isolates were MDR, while 12.9% were ESBL-producer. Of the total 33 isolates of S. aureus, 26 (78.8%) were MDR and 14 (42.4%) were methicillin resistant. A large number of MDR Acinetobacter spp. and MRSA has been noted in this study. The condition is worsened by the emergence of ESBL producing Acinetobacter spp. Hence, judicious use of antimicrobials is mandatory in clinical settings. Moreover, there should be vigilant surveillance of resistant clones in laboratories.

  13. Emerging threat of multidrug resistant bugs – Acinetobacter calcoaceticus baumannii complex and Methicillin resistant Staphylococcus aureus

    Science.gov (United States)

    2013-01-01

    Background Infections caused by bacteria such as multidrug resistant (MDR) Acinetobacter spp. and methicillin-resistant Staphylococcus aureus (MRSA) constitute a worldwide pandemic. Without gathering information about these strains, we cannot reduce the morbidity and mortality due to infections caused by these notorious bugs. Methods This study was conducted to identify the status of MDR Acinetobacter spp. and MRSA in a tertiary care centre of Nepal. Sputum, endotracheal aspirate and bronchial washing specimens were collected and processed from patients suspected of lower respiratory tract infection following standard microbiological methods recommended by the American Society for Microbiology (ASM). Double disk synergy test method was employed for the detection of extended-spectrum beta-lactamase (ESBL) in Acinetobacter isolates. Methicillin resistance in S. aureus was confirmed by using cefoxitin and oxacillin disks. Results Different genomespecies of Acinetobacter were isolated; these consisted of Acinetobacter calcoaceticus baumannii complex and A. lwoffii. Around 95% of Acinetobacter isolates were MDR, while 12.9% were ESBL-producer. Of the total 33 isolates of S. aureus, 26 (78.8%) were MDR and 14 (42.4%) were methicillin resistant. Conclusions A large number of MDR Acinetobacter spp. and MRSA has been noted in this study. The condition is worsened by the emergence of ESBL producing Acinetobacter spp. Hence, judicious use of antimicrobials is mandatory in clinical settings. Moreover, there should be vigilant surveillance of resistant clones in laboratories. PMID:23497675

  14. Phenotypic methods for determination of methicillin resistance in Staphylococcus spp. from health care workers

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    Marcelle Aquino Rabelo

    2013-04-01

    Full Text Available INTRODUCTION: Staphylococcus spp. is an important healthcare-associated pathogen and the identification of methicillin-resistant strains in samples of colonization may provide data to assist in the antimicrobial therapy success. OBJECTIVES: To determine the occurrence of colonization by methicillin-resistant Staphylococcus spp. (MRS, through the detection of the mecA gene and to evaluate different phenotypic methods for the presumptive detection of methicillin resistance in samples of the anterior nasal cavity and hands of the health care personnel of a university hospital in the state of Pernambuco, Brazil. METHODS: We selected the 28 isolates of Staphylococcus spp., which showed an intermediate or resistant phenotypic profile for oxacillin, detected by the Kirby Bauer technique. The methods used were disk-diffusion tests for cefoxitin, minimal inhibitory concentration by E-test for oxacillin, screening for oxacillin resistance and mecA gene detection by polymerase chain reaction (PCR. RESULTS: About the phenotypic methods utilized, only the E-test of oxacillin did not show a statistically significant difference in relation to PCR for the mecA gene detection, considered the gold standard. CONCLUSION: The E-test of oxacillin was the best of the phenotypic methods utilized. It is necessary to correctly detect MRS in healthy individuals, because they can act as carriers and can therefore be a potential source of microorganisms involved in hospital infections.

  15. An Investigation of Toxic Shock Syndrome Toxin-1 Gene in Methicillin-Resistant Clinical Strains of Staphylococcus aureus using Multiplex PCR Method

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    mohammad bokaiean

    2017-03-01

    Full Text Available Background and Objectives: Toxins produced by the bacteria are one of the most common cases, which can, together with other bacterial pathogens, cause or aggravate the disease. One of the diseases caused by bacterial toxins, is toxic shock syndrome. The tst gene encodes this toxin that can be easily transferred between different strains of Staphylococcus aureus. In this study, toxic shock syndrome toxin-1 gene was investigated in methicillin-resistant clinical strains of Staphylococcus aureus using multiplex PCR method. Methods: This study is a cross-sectional study, during a 9 month period, 470 samples were collected from patients hospitalized in different wards of treatment centers of Zahedan University of Medical Sciences in 2015. Phenotypic method was used for isolation and initial screening. Oxacillin and Cefoxitin discs were used. After isolation of resistant strains, femA and mecA genes and tst gene were investigated using phenotypic method and multiplex PCR method, respectively. Results: Of 170 clinical isolates of Staphylococcus aureus, 93 isolates were phenotypically methicillin-resistant, among which 89 isolates had mecA gene and 14 isolates had tst gene. Conclusion: The results indicated that the prevalence of methicillin-resistant strains and the strains carrying causative gene for TSST1, is high in Zahedan. Also, circulation of these isolates can lead to much more severe effects in individuals with weak immune system.

  16. Evaluation of Staphylococcus aureus resistance profile isolated from nursing students in an institution of higher education

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    Carolina Marino

    2016-09-01

    Full Text Available Staphylococcus aureus causes a large variety of infections, where many of them are acquired in the hospital environment. A significant part of the population is a nasal carrier of this type of microorganism. The present study evaluated the nasal colonization by S. aureus, identifying its resistance profile in nursing students from a private educational institute of higher education. Nasal swab samples were collected and identified for S. aureus. Moreover, an antibiogram assay was performed, followed by the search for ermA and ermC genes using PCR. Sixty-two students were included and we isolated 20 positive samples (32,5% for S. aureus. For the phenotypic profile, 30% were found to be resistant to Erythromycin and 10% to Oxacillin and Cefoxitin. For the D-test in the genotypic profile, 25% presented mecA gene (MRSA, 5% of ermA gene, 35% of ermC gene and 10% with ermC and mecA genes. These data reinforce the necessity of monitoring bacterial colonization in hospital environment, which are potentially resistant in health professionals.

  17. Agar dilution method for susceptibility testing of Neisseria gonorrhoeae

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    Marta C de Castillo

    1996-12-01

    Full Text Available The antibiotic susceptibilities of Neisseria gonorrhoeae isolates obtained from patients attending a clinic for sexually transmitted diseases in Tucumán, Argentina, were determined by the agar dilution method (MIC. 3.5% of the isolates produced ²-lactamase. A total of 96.5% of ²-lactamase negative isolates tested were susceptible to penicillin (MIC < 2 µgml-1; 14.03% of the tested isolates were resistant to tetracycline (MIC < 2 µgml-1, and 98% of the tested isolates were susceptible to spectinomycin (MIC < 64 µgml-1. The MICs for 95% of the isolates, tested for other drugs were: < 2 µgml-1 for cefoxitin, < 0.06 µgml-1 for cefotaxime, < 0.25 µgml-1 for norfloxacin, < 10 µgml-1 for cephaloridine, < 10 µgml-1 for cephalexin, and < 50 µgml-1 for kanamycin. Antibiotic resistance among N. gonorrhoeae isolates from Tucumán, Argentina, appeared to be primarily limited to penicillin and tetracycline, which has been a general use against gonorrhoeae in Tucumán since 1960. Periodic monitoring of the underlying susceptibility profiles of the N. gonorrhoeae strains prevalent in areas of frequent transmission may provide clues regarding treatment options and emerging of drug resistance.

  18. Phenotypic and genotypic detection of methicillin-resistant Staphylococcus aureus in hunting dogs in Maiduguri metropolitan, Borno State, Nigeria

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    Muhammad Mustapha

    2016-05-01

    Full Text Available Aim: To determine the presence of MRSA in hunting dogs in Maiduguri metropolitan. Materials and Methods: Phenotypic methods used includes microscopic technique, colony morphology study, catalase-coagulase tests, and the use of mannitol salt agar test, oxacillin resistance screening agar base, and antibiotic susceptibility testing methods. Genotypic approach was used for deoxyribonucleic acid extraction, and the presence of nuc and mecA gene was detected using polymerase chain reaction (PCR techniques. Results: Examination of 416 swab samples from nasal and perineal region of dogs revealed a total of 79.5% of S. aureus, where 62.5% of the isolates were MRSA. Molecular analysis revealed that 7nuc genes specific for S. aureus from 20 presumptive MRSA assay were all mecA PCR negative. The isolates were sensitive to gentamicin and ciprofloxacin but proved resistant to cefoxitin and oxacillin. Conclusion: High isolation rate of MRSA was found in hunting dogs. Significant level (p<0.05 of MRSA was isolated in the nasal cavity of hunting dogs than its perineum. Only nuc genes were detected from the MRSA isolates.

  19. Prevalence of plasmid-mediated AmpC beta-lactamases among Enterobacteriaceae in Algiers hospitals.

    Science.gov (United States)

    Iabadene, Hassen; Messai, Yamina; Ammari, Houria; Alouache, Souhila; Verdet, Charlotte; Bakour, Rabah; Arlet, Guillaume

    2009-10-01

    The aim of this study was to investigate the prevalence and diversity of plasmid-mediated AmpC cephalosporinases (PAcBLs) in clinical isolates of Enterobacteriaceae collected between 2003 and 2007 from three Algiers hospitals. Antibiograms were determined on Mueller-Hinton agar plates using the disk diffusion method, and minimum inhibitory concentrations were determined by Etest. Isolates resistant to cefoxitin or ceftazidime were screened for bla(CMY), bla(DHA), bla(FOX) and bla(ACC) as well as extended-spectrum beta-lactamase (ESBL) genes by polymerase chain reaction (PCR). PCR products were sequenced by the Sanger method. Plasmid incompatibility grouping was conducted by PCR-based replicon typing. The prevalence of PAcBLs was 2.18% (11/505), comprising 8 CMY-2 and 3 DHA-1 enzymes. CTX-M-15 was co-produced with CMY-2 in three isolates and with DHA-1 in one isolate; the two remaining DHA-1-producers co-expressed SHV-12 ESBL. This is the first report of plasmid-mediated AmpC from Algeria, with the first detection of DHA-1 in Enterobacter cloacae.

  20. Bacteriological Profile and Antimicrobial Susceptibility Patterns of Bacteria Isolated from Pus/Wound Swab Samples from Children Attending a Tertiary Care Hospital in Kathmandu, Nepal

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    Salu Rai

    2017-01-01

    Full Text Available In Nepal, little is known about the microbiological profile of wound infections in children and their antimicrobial susceptibility patterns. Total of 450 pus/wound swab samples collected were cultured using standard microbiological techniques and the colonies grown were identified with the help of biochemical tests. The antimicrobial susceptibility testing was performed by Kirby-Bauer disc diffusion technique. Methicillin-resistant Staphylococcus aureus isolates were detected by using cefoxitin disc and confirmed by determining minimum inhibitory concentrations (MIC of oxacillin. 264 (59% samples were culture positive. The highest incidence of bacterial infections was noted in the age group of less than 1 year (76%. Out of 264 growth positive samples, Gram-positive bacteria were isolated from 162 (61% samples and Gram-negative bacteria were found in 102 (39% samples. Staphylococcus aureus (99% was the predominant Gram-positive bacteria isolated and Pseudomonas aeruginosa (44% was predominant Gram-negative bacteria. About 19% of S. aureus isolates were found to be methicillin-resistant MIC of oxacillin ranging from 4 μg/mL to 128 μg/mL. Among the children of Nepal, those of age less than 1 year were at higher risk of wound infections by bacteria. Staphylococcus aureus followed by Pseudomonas aeruginosa were the most common bacteria causing wound infections in children.

  1. Epidemiology and antimicrobial resistance of B. fragilis group organisms isolated from clinical specimen and human intestinal microbiota Epidemiologia e resistência a antimicrobianos de microorganismos do grupo B. fragilis isolados de espécime clínico e microbiota intestinal humana

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    Cibele Barreto Mano de Carvalho

    1996-10-01

    Full Text Available Epidemiological aspects and the antimicrobial susceptibility profile of the Bacteroides fragilis group isolated from clinical and human intestinal specimens were examined in this study. B. fragilis group strains were isolated from 46 (37% of 124 clinical specimens and the source of the samples was: Blood culture (3, intraabdominal infection (27, brain abscess (2, soft tissue infection (17, respiratory sinus (3, pleural aspirate (9, breast abscess (3, surgical infected wound (22, pelvic inflammatory disease (22, chronic otitis media (9 and miscellaneous (7. Intraabdominal and soft tissue infections were responsible for more than half of the clinical isolates. Susceptibility to penicillin, cefoxitin, tetracycline, metronidazole, chloramphenicol and clindamycin was examined. All isolates were susceptible to metronidazole and chloramphenicol. For clindamycin and cefoxitin the resistance rates observed were 21.7% and 10.9% respectively. Susceptibility profiles varied among the different species tested. A total of 37 species of B. fragilis group isolated from intestinal microbiota of individuals who had no antimicrobial therapy for at least 1 month before the sampling was also examined. All strains were also susceptible to chloramphenicol and motronidazole and the resistance rates to clindamycin and cefoxitin were 19.4% and 5.4% respectively. A few institutions, in Brazil, have monitored the antimicrobial susceptibility of B. fragilis group strains isolated from anaerobic infections. The resistance rates to cefoxitin and clindamycin and the variation in susceptibility patterns among the species isolated in this study emphasize the need for monitoring of susceptibility patterns of B. fragilis group organisms isolated, especially at our University Hospitals.Alguns aspectos epidemiológicos e o perfil de sensibilidade a antimicrobianos de amostras do grupo B. fragilis isoladas de espécime clínico e microbiota intestinal humana foram delineados neste

  2. Risk factors assessment for nasal colonization of Staphylococcus aureus and its methicillin resistant strains among pre-clinical medical students of Nepal.

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    Ansari, Shamshul; Gautam, Rajendra; Shrestha, Sony; Ansari, Safiur Rahman; Subedi, Shankar Nanda; Chhetri, Muni Raj

    2016-04-12

    Staphylococcus aureus (S. aureus), a normal flora of nasal cavity, can cause minor to life threatening invasive diseases and nosocomial infections. Methicillin resistant strains of S. aureus are causing a great challenge for treatment options. Therefore, the purpose of this study was to assess the nasal carriage rate of S. aureus, its methicillin resistant strains and risk factors in medical students prior to clinical exposure. The bacterial growth of S. aureus from nasal swab culture was identified by using standard microbiological methods recommended by American Society for Microbiology. Modified Kirby-Bauer disk diffusion method was used for antibiotic susceptibility testing and methicillin resistance was confirmed using cefoxitin and oxacillin disks. D-zone test method was used to determine the inducible clindamycin resistance. Among 200 participants, nasal carriage of S. aureus was detected from 30 (15%) subjects. Upper respiratory tract infections significantly (P aureus and their methicillin resistant strains. All of the isolates were reported to be susceptible to vancomycin and teicoplanin. S. aureus strains detected from 8 (4%) students were confirmed to be methicillin resistant. The result of our study demands for strict policy to screen all the students for nasal carriage of S. aureus and its MRSA strains to minimize the transmission of this organism from community to hospital settings.

  3. Detection of Genes for Superantigen Toxins in Methicillin-Resistant Staphylococcus aureus Clinical Isolates in Karachi

    International Nuclear Information System (INIS)

    Taj, Y.; Fatima, I.; Ali, S. W.; Kazmi, S. U.

    2014-01-01

    Objective: To detect genes for enterotoxins, exfoliative and toxic shock syndrome toxins in Staphylococcus aureus (S. aureus) strains isolated from clinical specimens. Study Design: Cross-sectional observational study. Place and Duration of Study: Department of Molecular Genetics, Dr. Ziauddin Hospital, Karachi, from January to December 2010. Methodology: Two hundred and ninety eight S. aureus clinical isolates were obtained from various clinical samples received at Dr. Ziauddin Hospital, Karachi. Out of these, 115 were detected as methicillin resistant (MRSA) by cefoxitin disk diffusion test showing a prevalence rate of 38.6%. Detection of individual toxin genes was performed by Polymerase Chain Reaction (PCR) by using only one primer pair for each tube. Uniplex primers were preferred as multiplex primers are longer in base pairs and have the potential for cross reaction due to non-specific binding and increase in optimization time. Results: The possession of a single gene or more than a single gene in MRSA isolates was found in 61.73% of clinical samples; the highest number was found in pus swab, followed by sputum, blood, urethral swab, and urine. The prevalence of toxin genes was higher in MRSA as compared to methicillin sensitive (MSSA) isolates (19.12%). Conclusion: PCR detects strains possessing toxin genes independent of their expression. The possession of genes for super-antigens seems to be a frequent and habitual trait of S. aureus more so in MRSA. (author)

  4. Prevalence of methicillin resistant Staphylococcus aureus in Lumbini Medical College and Teaching Hospital, Palpa, Western Nepal.

    Science.gov (United States)

    Raut, Shristi; Bajracharya, Kishor; Adhikari, Janak; Pant, Sushama Suresh; Adhikari, Bipin

    2017-06-02

    Multidrug resistant Staphylococcus aureus is common in both tertiary and primary health care settings. Emergence of methicillin resistance in S. aureus (MRSA) along with macrolide, lincosamide, streptogramin B (MLSB) has made treatment of Staphylococcal infection more challenging. The main objective of this study was to detect MRSA, MLSB (inducible; MLSBi and constitutive; MLSBc) resistant S. aureus using phenotypic methods and to determine their antibiogram. Various samples were collected from 1981 patients who attended Lumbini Medical College and Teaching Hospital (LMCTH) during the period of 6 months from September 2015 to February 2016. Out of a total of 1981 samples, 133 S. aureus were isolated. Cefoxitin was used to detect MRSA by the disk diffusion test. Inducible clindamycin resistance (MLSBi) was detected by the D-zone test. The antibiotic profile of all isolates was tested by a modified Kirby Bauer disk diffusion method. Among 133 S. aureus, there were 58 (43.6%) MRSA, 34 (25.6%) MLSBi and 30 (22.6%) MLSBc. Of a total of 64 MLSB, a significant proportion (62.5%) was MRSA (p aureus, MRSA showed significant resistance to 9 (p resistance to multiple antibiotics (p resistance profiles from this study can optimize the treatment of multi-drug resistant S. aureus.

  5. Occurrence and characterisation of MRSA and extended-spectrum ß-lactamases producing Escherichia coli isolated from mastitic cows’ milk

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    Weiner Marcin

    2015-06-01

    Full Text Available The aim of study was the preliminary evaluation of the occurrence of methicillin-resistant Staphylococcus aureus (MRSA and extended spectrum ß-lactamases (ESBL - producing Escherichia coli in 650 milk and inflammatory secretions from cows with clinical or subclinical mastitis. One millilitre of the sample was added to Mueller-Hinton broth supplemented with 6.5% NaCl, Tryptone Soya Broth with cefoxitin and aztreonam, and then to MRSA ID agar. Presumptive MRSA colonies were analysed for the presence of mecA gene. Parallel to MRSA identification, the samples were incubated in buffered peptone water, lauryl tryptose broth and McConkey agar supplemented with cefotaxim for ESBL-producing E. coli isolation. These bacteria were identified using API Rapid 32 E and the ability of ESBL production was initially established using disc test D68C and confirmed by MIC technique using Sensititre ESBL plates. The primers (blaCTX, blaTEM, blaSHV, and blaCMY-2-group for the detection of some of the genes encoding ESBL production were used. The 45 strains of S. aureus with mecA gene and 41 strains of E. coli with blaTEM gene were detected.

  6. Hospital Epidemiology of Methicillin-Resistant Staphylococcus aureus in a Tertiary Care Hospital in Moshi, Tanzania, as Determined by Whole Genome Sequencing

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    Happiness H. Kumburu

    2018-01-01

    Full Text Available Objective. To determine molecular epidemiology of methicillin-resistant S. aureus in Tanzania using whole genome sequencing. Methods. DNA from 33 Staphylococcus species was recovered from subcultured archived Staphylococcus isolates. Whole genome sequencing was performed on Illumina Miseq using paired-end 2×250 bp protocol. Raw sequence data were analyzed using online tools. Results. Full susceptibility to vancomycin and chloramphenicol was observed. Thirteen isolates (43.3% resisted cefoxitin and other antimicrobials tested. Multilocus sequence typing revealed 13 different sequence types among the 30 S. aureus isolates, with ST-8 (n = seven, 23% being the most common. Gene detection in S. aureus stains were as follows: mecA, 10 (33.3%; pvl, 5 (16.7%; tst, 2 (6.7%. The SNP difference among the six Tanzanian ST-8 MRSA isolates ranged from 24 to 196 SNPs and from 16 to 446 SNPs when using the USA300_FPR3757 or the USA500_2395 as a reference, respectively. The mutation rate was 1.38×10-11 SNPs/site/year or 1.4×10-6 SNPs/site/year as estimated by USA300_FPR3757 or the USA500_2395, respectively. Conclusion. S. aureus isolates causing infections in hospitalized patients in Moshi are highly diverse and epidemiologically unrelated. Temporal phylogenetic analysis provided better resolution on transmission and introduction of MRSA and it may be important to include this in future routines.

  7. Methicillin-resistant Staphylococcus aureus in Zimbabwe.

    Science.gov (United States)

    Mauchaza, Kathrine; Madzimbamuto, Farai D; Waner, Seymour

    2016-06-01

    The prevalence of Methicillin Resistant Staphylococcus aureus (MRSA) in Africa is sparsely documented. In Zimbabwe there is no routine patient or specimen screening for MRSA. The aim of this study was to document the presence and epidemiology of MRSA in Zimbabwe. The study was done in one private sector laboratory with a national network that serves both public and private hospitals. The sample population included in-patients and outpatients, all ages, both genders, all races and only one positive specimen per patient was counted. Specimens testing positive for Staphylococcus aureus in this laboratory were further tested for MRSA using cefoxitin, by standard laboratory procedures. Data was collected from 1(st) June 2013 to 31(st) May 2014. MRSA was positive in 30 of 407 [7.0%] cases of Stapylococcus aureus reported from the laboratory. All age groups were affected from neonates to geriatrics. All specimens had similar antibiotic susceptibility pattern. Resistance was high for most widely used drugs in Zimbabwe with high sensitivity to vancomycin, linezolid and teicoplanin. Although there are no recent reports in the literature of the presence of MRSA in Zimbabwe, this study documented a 7.0% prevalence. Resistance to common antibiotics is high and antibiotic oversight is required to control the emergence of resistance to these few expensive drugs. Study was supported by Department of Anaesthesia and Critical Care funds.

  8. Susceptibility of Staphylococcus aureus Clinical Isolates to Propolis Extract Alone or in Combination with Antimicrobial Drugs

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    Mieczysław Sajewicz

    2013-08-01

    Full Text Available The objective of this study was to assess in vitro the antimicrobial activity of ethanolic extract of Polish propolis (EEPP against methicillin-sensitive Staphylococcus aureus (MSSA and methicillin-resistant Staphylococcus aureus (MRSA clinical isolates. The combined effect of EEPP and 10 selected antistaphylococcal drugs on S. aureus clinical cultures was also investigated. EEPP composition was analyzed by a High Performance Liquid Chromatography (HPLC method. The flavonoid compounds identified in Polish Propolis included flavones, flavonones, flavonolols, flavonols and phenolic acids. EEPP displayed varying effectiveness against twelve S. aureus strains, with minimal inhibitory concentration (MIC within the range from 0.39 to 0.78 mg/mL, determined by broth microdilution method. The average MIC was 0.54 ± 0.22 mg/mL, while calculated MIC50 and MIC90 were 0.39 mg/mL and 0.78 mg/mL, respectively. The minimum bactericidal concentration (MBC of the EEPP ranged from 0.78 to 3.13 mg/mL. The in vitro combined effect of EEPP and 10 antibacterial drugs was investigated using disk diffusion method-based assay. Addition of EEPP to cefoxitin (FOX, clindamycin (DA, tetracycline (TE, tobramycin (TOB, linezolid (LIN, trimethoprim+sulfamethoxazole (SXT, penicillin (P, erythromycin (E regimen, yielded stronger, cumulative antimicrobial effect, against all tested S. aureus strains than EEPP and chemotherapeutics alone. In the case of ciprofloxacin (CIP and chloramphenicol (C no synergism with EEPP was observed.

  9. Yersinia enterocolitica strains associated with human infections in Switzerland 2001-2010.

    Science.gov (United States)

    Fredriksson-Ahomaa, M; Cernela, N; Hächler, H; Stephan, R

    2012-07-01

    Yersinia enterocolitica infections are common in humans. However, very scarce data are available on the different biotypes and virulence factors of human strains, which has proved to be problematic to assess the clinical significance of the isolated strains. In this study, the presence of the ail gene and distribution of different bio- and serotypes among human Y. enterocolitica strains and their possible relation to the genotype and antimicrobial resistance were studied. In total, 128 Y. enterocolitica strains isolated from human clinical samples in Switzerland during 2001-2010 were characterised. Most (75 out of 128) of the Y. enterocolitica strains belonged to biotypes 2, 3 or 4 and carried the ail gene. One of the 51 strains that belonged to biotype 1A was also ail positive. Most of the ail-positive strains belonged to bioserotype 4/O:3 (47 out of 76) followed by 2/O:9 (22 out of 76). Strains of bioserotype 4/O:3 were dominant among patients between 20 and 40 years old and strains of biotype 1A dominate in patients over 40 years. Strains belonging to biotypes 2, 3 and 4, which all carried the ail gene, exhibited a high homogeneity with PFGE typing. Y. enterocolitica 2/O:5,27 and 2/O:9 strains showed resistance to amoxicillin/clavulanic acid and cefoxitin, but Y. enterocolitica 4/O:3 strains did not.

  10. Evaluation of different phenotypic methods for detection of amp c beta-lactamase producing bacteria in clinical isolates

    International Nuclear Information System (INIS)

    Hassan, A.; Usman, J.; Kalim, F.; Gill, M.M.; Khalid, A.; Iqbal, M.; Ingram, P.

    2013-01-01

    To compare the sensitivity and specificity of different phenotypic methods for detection of Amp C betalactamase producing bacteria. Study Design: Analytical study. Place and Duration of Study: Department of Microbiology, Army Medical College / National University of Sciences and Technology (NUST), Islamabad, Pakistan, from June 2010 to December 2010. Methodology: A total of 150 clinical isolates were screened for presence of Amp C beta-lactamase by using the cefoxitin disc. The confirmatory methods evaluated were inhibitor based assay (boronic acid), Amp C disc test and Amp C Etest. Three dimensional enzyme extract assay was used as the reference method for determining the sensitivity and specificity. Results: Among the total isolates tested, 62.8% bacteria showed the presence of Amp C beta-lactamase by standard three dimensional enzyme extract assay. Among the three methods compared, boronic acid disk test found out to be highly sensitive (88%) and specific (92%) for the detection of Amp C beta-lactamase producing bacteria. Conclusion: Detection of Amp C production is crucial in order to establish the antibiotic therapy and to attain the favourable clinical outcomes. Implementation of simple tests like boronic acid disk tests in the laboratories will help to alleviate the spread of Amp C beta-lactamase harboring organisms. (author)

  11. Assessment of antibiotic resistance of Escherichia coli isolates and screening of Salmonella spp. in wild ungulates from Portugal.

    Science.gov (United States)

    Dias, Diana; Torres, Rita T; Kronvall, Göran; Fonseca, Carlos; Mendo, Sónia; Caetano, Tânia

    2015-09-01

    Antibiotic resistance is an emerging global problem. Wild animals are rarely exposed to antibiotics and therefore low levels of antibiotic resistance are expected. However, the growing interactions of these animals with humans and livestock may have a huge impact on their bacterial flora. This study aimed to assess the levels of antibiotic resistance in Escherichia coli isolated from widespread wild ungulates in Portugal. The interpretation of inhibition zone diameters was performed according to clinical breakpoints and epidemiological cut-offs, determined with the normalized resistance interpretation (NRI) method. For clinical breakpoints, 16% of the isolates were resistant to at least one antibiotic, including ampicillin (10%), tetracycline (9%), streptomycin (5%) co-trimoxazole (4%), amoxicillin/clavulanic acid (1%) and cefoxitin (1%). The levels of resistance detected in E. coli strains isolated from wild boar were statistically different for ampicillin and co-trimoxasol. According to NRI cut-offs, 10% of the population showed a non-wild-type phenotype against at least one antibiotic, also including tetracycline (9%), co-trimoxazole (6%), streptomycin (4%), ampicillin (2%) and amoxicillin/clavulanic acid (1%). Considering this parameter of comparison, no statistically different levels of resistance were identified between E. coli recovered from the three wild ungulates. Screening of Salmonella spp., which can be potentially pathogenic, was also performed, revealing that its prevalence was very low (1.5%). The study demonstrated that wild ungulates from Portugal are also reservoirs of antibiotic-resistant bacteria. Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  12. Prevalence of beta-lactamases among ampicillin-resistant Escherichia coli and Salmonella isolated from food animals in Denmark

    DEFF Research Database (Denmark)

    Olesen, Inger; Hasman, Henrik; Aarestrup, Frank Møller

    2004-01-01

    The genetic background for beta-lactamase-mediated resistance to beta-lactam antibiotics was examined by PCR and sequencing in 160 ampicillin-resistant isolates (109 Escherichia coli and 51 Salmonella) obtained from healthy and diseased food animals in Denmark. Sequencing revealed three different...... variants of bla(TEM-1), of which bla(TEM-1b) was the most frequently detected (80 E. coli and 47 Salmonella), followed by bla(TEM-1a) (eight E. coli, one Salmonella) and bla(TEM-1c) (seven E. coli). A few isolates were found to express OXA, TEM-30, or PSE beta-lactamases. Mutations in the ampC promoter...... leading to increased production of the AmpC beta-lactamase were demonstrated in 11 cefoxitin-resistant or intermediate E. coli isolates. Nine of these isolates did not contain any bla(TEM) genes, whereas the remaining two did. No genes encoding SHV or extended-spectrum beta-lactamases were detected. Two...

  13. In vitro susceptibility of chloramphenicol against methicillin-resistant staphylococcus aureus

    International Nuclear Information System (INIS)

    Fayyaz, M.; Mirza, I.A.; Hussain, A.; Abbasi, S.A.; Ali, S.; Ahmed, Z.

    2013-01-01

    To determine the in vitro susceptibility of chloramphenicol against methicillin-resistant Staphylococcus aureus. Study Design: Cross-sectional study. Place and Duration of Study: Department of Microbiology, Armed Forces Institute of Pathology, Rawalpindi, from January to June 2012. Methodology: One hundred and seventy four isolates of methicillin-resistant Staphylococcus aureus were included in this study using cefoxitin (30 A g) disc for detection. Minimum inhibitory concentration (MIC) of chloramphenicol against MRSA was determined by using E-strip (AB BIO DISK). The susceptibility was determined by swabbing the Mueller-Hinton agar (MHA) plates with the resultant saline suspension of MRSA and applying E-strip of chloramphenicol from AB Biodisk Sweden and determining the MIC of chloramphenicol (in A g/ml). Clinical and Laboratory Standards Institute (CLSI) recommendations of A=8 A g/ml being sensitive, 16 A g/ml as intermediate and A 32 A g/ml as resistant were followed in interpreting the results. Results: Out of the 174 MRSA isolates, 132 (75.86%) isolates were susceptible to chloramphenicol with MICs of A=8 A g/ml, 38 (21.84%) were resistant A=32 A g/ml while 4 (2.30%) were in intermediate range with MIC of 16 A g/ml. Conclusion: Chloramphenicol has shown good in vitro activity against MRSA and is likely to have a key role in the treatment of MRSA infections providing us a good alternative to newer expensive antimicrobials in resource limited countries. (author)

  14. Staphylococcus saprophyticus Recovered from Humans, Food, and Recreational Waters in Rio de Janeiro, Brazil

    Science.gov (United States)

    de Sousa, Viviane Santos; da-Silva, Ana Paula de Souza; Sorenson, Leif; Paschoal, Raphael Paiva; Rabello, Renata Fernandes; Campana, Eloiza Helena; Pinheiro, Márcia Soares; dos Santos, Lyssa Oliveira Ferreira; Martins, Natacha; Botelho, Ana Carolina Nunes; Fracalanzza, Sérgio Eduardo Longo; Riley, Lee Woodland; Sensabaugh, George

    2017-01-01

    Staphylococcus saprophyticus is an important agent of urinary tract infection (UTI) in young women, but information about this pathogen in human microbiota and in common environment is lacking. The aim of this study was to characterize S. saprophyticus isolates from genitoanal microbiota of 621 pregnant women, 10 minas cheese packs, and five beaches in Rio de Janeiro city and compare PFGE profiles of these isolates with five UTI PFGE clusters described in this city. We investigated 65 S. saprophyticus isolates from microbiota, 13 from minas cheese, and 30 from beaches and 32 UTI isolates. Antimicrobial resistance was determined by disk diffusion, MIC by agar dilution, and PCR. Erythromycin-resistance genes erm(C), msr(A), msr(B), mph(C), and lin(A) were found in 93% of isolates. Trimethoprim-sulfamethoxazole resistance correlated with dfrG or dfrA genes. Three cefoxitin-resistant isolates carried the mecA gene. All isolates obtained from cheese were susceptible to all antimicrobial agents. Six of 10 pregnant women with >1 isolate had monoclonal colonization. Isolates from pregnant women shared 100% similarity with UTI PFGE cluster types A and E obtained almost 10 years previously, suggesting temporal persistence of S. saprophyticus. Antimicrobial resistance of beach isolates reflected the profiles of human isolates. Taken together, results indicate a shared source for human and environmental isolates. PMID:28630628

  15. Phenotypic and Genotypic Antibiotic Resistance of Salmonella from Chicken Carcasses Marketed at Ibague, Colombia

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    D Cortes Vélez

    Full Text Available ABSTRACT Salmonella enterica is responsible for alimentary toxic infections associated with the consumption of contaminated poultry products and the antimicrobial resistant patterns of Salmonella circulating in the Tolima region are currently unknown. To address this issue, both the phenotype and genotype antibiotic resistance patterns of 47 Salmonella isolated from raw chicken carcasses sold at the Ibague city were analyzed by the disc diffusion, microdilution and PCR assays. All 47 Salmonella isolates showed resistance to five or more antimicrobial agents. Resistance to Ampicillin (AMP, Amikacin (AMK, Gentamicin (GEN, Tobramycin (TOB, Cefazoline (CFZ, Cefoxitin (FOX, Nitrofurantoin (NIT, Trimethoprim-Sulfamethoxazole (SXT, Tetracycline (TET, Ciprofloxacin (CIP and Enrofloxacin (ENR was observed in 42.35% of Salmonella isolates. All tested S. Paratyphi B var Java isolates showed resistance to at least 12 antibiotics. S. Hvittingfoss showed resistance to 5 antibiotics, whereas S. Muenster showed resistance to seven antibiotics. Amplification of a number of antibiotic resistance genes showed that blaTEM (100% correlated well with resistance to Ampicilin and Cephalosporin, whereas aadB (87% correlated well with resistance to Aminoglycosides. It is concluded that Salmonella isolated from raw chicken meat marketed at Ibague showed MDR by both phenotypic and genotypic methods and they may represent an important threat to human health. Additional studies are needed to establish the relationship between antibiotic resistance in Salmonella from poultry products and clinical isolates.

  16. Short communication: Characterization of methicillin-resistant Staphylococcus aureus isolated from raw milk fresh cheese in Colombia.

    Science.gov (United States)

    Herrera, Fanny C; García-López, María-Luisa; Santos, Jesús A

    2016-10-01

    The aim of this study was the characterization of a collection of 8 methicillin-resistant Staphylococcus aureus (MRSA) isolates, obtained from samples of fresh cheese (Doble Crema) produced from raw cow milk in small dairies in Colombia. All the isolates harbored the mecA and Panton-Valentine leukocidin (PVL) genes, presented with SCCmec type IV, and belonged to multilocus sequence type 8 and spa type 024. Seven isolates presented 3 closely related pulsed-field gel electrophoresis profiles. Three of them carried the staphylococcal enterotoxin B gene. The isolates were resistant to cefoxitin, oxacillin, penicillin, and ampicillin and susceptible to all non-β-lactams antibiotics tested, with minimum inhibitory concentration values for oxacillin of 4 to 8mg/L. The isolates belonged to the community-acquired MRSA group, suggesting a human source of contamination. The risk of human infection by MRSA via contaminated foods is considered low, but contaminated food commodities can contribute to the worldwide dissemination of clones of community-acquired MRSA. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  17. Prevalence of beta-lactamases among ampicillin-resistant Escherichia coli and Salmonella isolated from food animals in Denmark

    DEFF Research Database (Denmark)

    Olesen, Inger; Hasman, Henrik; Aarestrup, Frank Møller

    2004-01-01

    leading to increased production of the AmpC beta-lactamase were demonstrated in 11 cefoxitin-resistant or intermediate E. coli isolates. Nine of these isolates did not contain any bla(TEM) genes, whereas the remaining two did. No genes encoding SHV or extended-spectrum beta-lactamases were detected. Two......The genetic background for beta-lactamase-mediated resistance to beta-lactam antibiotics was examined by PCR and sequencing in 160 ampicillin-resistant isolates (109 Escherichia coli and 51 Salmonella) obtained from healthy and diseased food animals in Denmark. Sequencing revealed three different...... variants of bla(TEM-1), of which bla(TEM-1b) was the most frequently detected (80 E. coli and 47 Salmonella), followed by bla(TEM-1a) (eight E. coli, one Salmonella) and bla(TEM-1c) (seven E. coli). A few isolates were found to express OXA, TEM-30, or PSE beta-lactamases. Mutations in the ampC promoter...

  18. Effects of Menthol Supplementation in Feedlot Cattle Diets on the Fecal Prevalence of Antimicrobial-Resistant Escherichia coli.

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    C C Aperce

    Full Text Available The pool of antimicrobial resistance determinants in the environment and in the gut flora of cattle is a serious public health concern. In addition to being a source of human exposure, these bacteria can transfer antibiotic resistance determinants to pathogenic bacteria and endanger the future of antimicrobial therapy. The occurrence of antimicrobial resistance genes on mobile genetic elements, such as plasmids, facilitates spread of resistance. Recent work has shown in vitro anti-plasmid activity of menthol, a plant-based compound with the potential to be used as a feed additive to beneficially alter ruminal fermentation. The present study aimed to determine if menthol supplementation in diets of feedlot cattle decreases the prevalence of multidrug-resistant bacteria in feces. Menthol was included in diets of steers at 0.3% of diet dry matter. Fecal samples were collected weekly for 4 weeks and analyzed for total coliforms counts, antimicrobial susceptibilities, and the prevalence of tet genes in E. coli isolates. Results revealed no effect of menthol supplementation on total coliforms counts or prevalence of E. coli resistant to amoxicillin, ampicillin, azithromycin, cefoxitin, ceftiofur, ceftriaxone, chloramphenicol, ciprofloxacin, gentamicin, kanamycin, nalidixic acid, streptomycin, sulfisoxazole, and sulfamethoxazole; however, 30 days of menthol addition to steer diets increased the prevalence of tetracycline-resistant E. coli (P < 0.02. Although the mechanism by which menthol exerts its effects remains unclear, results of our study suggest that menthol may have an impact on antimicrobial resistance in gut bacteria.

  19. FEATURES OF THE LARGE INTESTINE MICROFLORA OF CHILDREN – DONOR LIVER TRANSPLANT RECIPIENTS

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    N. I. Gabrielyan

    2013-01-01

    Full Text Available Aim. The study microecology of the large intestine of children with cirrhosis before transplantation of the share liver. Materials and methods. Studied the flora of the colon 157 children of 1 to 17 years admitted to hospital for liver transplantation fragment from a related donor. Identification was carried out using microbial panels BD Crystal and databases BBL Crystal MIND. Methicillin-resistant staphylococci were determined by their sensiti- vity to oxacillin and cefoxitin. Beta-lactamase activity was tested using discs with ceftazidime and ceftazidime/ clavulanic acid. Results. Microecological revealed deep irregularities in the large intestine transplantation in children up lobe of the liver on a spectrum and composition of the microflora. Among the resident microflora decreased levels of bifidobacteria, lactobacilli and coliform bacteria, especially in children under one year. A sig- nificant portion of the children surveyed (over 60–70% had an increase of frequency of finding stateally bacteria, especially Klebsiella and enterobacteria in third children – non-fermenting bacteria – Pseudomonas and Acine- tobacter spp. Revealed the spread of strains of gram-negative bacteria with extended-spectrum betalaktamaz.Conclusion. Expressed microecological violations in the large intestine in children with higher levels of bac- teria are conditionally risk factor reeks of infectious complications in the postoperative period and require are complex tools to assist in eliminatsii.s given antibiotic resistance of bacteria. 

  20. Susceptibility trends of Bacteroides fragilis group isolates from Buenos Aires, Argentina Tendencias en el perfil de sensibilidad de aislamientos del grupo Bacteroides fragilis obtenidos en Buenos Aires, Argentina

    Directory of Open Access Journals (Sweden)

    L. Fernández Canigia

    2007-09-01

    Full Text Available The aim of this study was to analyze the susceptibility trends to seven antibiotics of Bacteroides fragilis group isolates based on three survey studies performed by the Committee of Anaerobic Bacteria between 1989 and 2002. Fifty three, 82 and 65 B. fragilis group isolates were collected during each period. The antimicrobial agents included were: ampicillin, ampicillin-sulbactam (2:1, cefoxitin, piperacillin, imipenem, clindamycin, and metronidazole. Minimal inhibitory concentrations (MICs were determined according to the reference agar dilution method described by the Clinical and Laboratory Standards Institute (CLSI, formerly NCCLS. The most active antibiotics for B. fragilis and non- B. fragilis species throughout the three periods were: imipenem with 99.1 and 100% of activity, respectively, and metronidazole with 100% of activity. The susceptibility to ampicillin-sulbactam showed a decrease, from 100% to 90.3% and to 82.4 % in the last period, for both B. fragilis and non-B. fragilis species, respectively. The overall susceptibility rates for cefoxitin, piperacillin, and clindamycin were significantly different between B. fragilis and non-B. fragilis species (84.2% vs. 56.5%; 85.9% vs. 66.7% and 88.8% vs. 64.7%, respectively, pEl objetivo de este estudio fue evaluar las variaciones en el perfil de sensibilidad frente a siete antimicrobianos de aislamientos del grupo Bacteroides fragilis, mediante el análisis de tres relevamientos realizados por la Subcomisión de Bacterias Anaerobias de la Asociación Argentina de Microbiología (años 1989-1991, 1996-1998 y 1999-2002. En los citados períodos se recolectaron 53, 82 y 65 aislamientos del grupo B. fragilis. Se evaluó la actividad de: ampicilina, ampicilina-sulbactama (2:1, cefoxitina, piperacilina, imipenem, clindamicina y metronidazol. La concentración inhibitoria mínima (CIM se determinó utilizando el método de dilución en agar, según las normas del Clinical and Laboratory

  1. Perfil de susceptibilidade a antimicrobianos em amostras de cocos Gram-positivos, catalase negativos, isoladas de mastite subclínica bubalina Profile of antimicrobial susceptibility in strains of Gram positive cocos, negative catalase, isolated from buffalo subclinical mastitis

    Directory of Open Access Journals (Sweden)

    Maria C.E. Vianni

    2003-06-01

    the State of Rio de Janeiro. The test used was diffusion of disks in agar Müller Hinton, according to recommendations of the National Committee for Clinical Laboratory Standards - NCCLS. There were tested disks with ampicillin (10mg, cefalotin (30mg, cefotaxime (30mg, cefoxitin (30mg, cloranfenicol (30mg, eritromycin (15mg, gentamycin (10mg, nitrofurantoin (300mg, norfloxacin (10mg, penicillin (10 IU, tetracyclin (30mg and vancomycin (30mg. The results showed that with Lactococcus garvieae, the most efficient antimicrobial was nitrofurantoin, revealing 85.71% sensibility, followed by cefotaxime (61.90%, vancomycin (52.38%, norfloxacin (47.62& and cefalotin (47.62%. The highest resistance was developed against penicillin and ampicillin, with 95.24% resistance for the two antimicrobials. The susceptibility profile developed by the strains of Enterococcus gallinarum showed low sensibility against the tested antimicrobials; the highest resistance observed was against eritromycin and gentamycin, with 33.34% sensibility for both. The antimicrobial evaluation showed 100% resistance against vancomycin and tetracyclin, followed by cloranfenicol, penicillin, ampicillin, cefoxitin, cefotaxim, norfloxacin and nitrofurantoin; all of them showed a resistance of 83.33% with the samples tested.

  2. Investigation of susceptibility of Staphylococcus species to some antibacterial drugs by disk diffusion and broth microdilution

    Directory of Open Access Journals (Sweden)

    Ašanin Jelena

    2012-01-01

    Full Text Available The objective of this work was to identify isolated Staphylococcus species and to investigate their sensitivity to some antibacterial drugs. The material used for these investigations were Staphylococcus isolates originating from milk samples. A total of 25 strains of Staphylococcus isolates were examined, including 24 from milk samples from cows with mastitis, and one strain was isolated from a milk sample from a cow following treatment for mastitis. For primary identification, catalase and oxidase tests were used, as well as the free coagulase test. Following the preliminary tests, the isolated strains were identified using commercial systems ID32 STAPH (bioMérieux, France and the BBL Crystal Gram-Positive ID Kit (Becton Dickinson, USA according to the enclosed instructions. The Staphylococcus isolates were examined for sensitivity to the following: oxacillin, penicillin, cefoxitin, gentamicin, erythromycin, chloramphenicol, tetracycline, ciprofloxacin, sulfametoxazol/trimetoprim, and vacomycin using the disk diffusion method and the broth microdilution method as recommended by the Clinical and Laboratory Strandards Institute - CLSI(2003, and the results were interpreted according to CLSI recommendations from 2008 and 2010. Antibiogram disks manufactured by Becton Dickinson (USA were used, and the broth microdilution method was applied using pure antibiotic substances from different manufacturers: erythromycin, chloramphenicol, cefoxitin, gentamicin, oxacillin, tetracycline (Sigma Aldrich, USA, sulfametoxazol (Fluka, USA, penicillin (Calbiochem, Germany, vancomycin (Abbott laboratories, USA, ciprofloxacin and trimetoprim (Zdravlje A.D., Serbia. All 25 strains were catalase positive and oxidase negative. Of the 25 strains, 19 were coagulase positive and 6 were coagulase negative.With the implementation of the disk diffusion method on 19 strains of S. aureus, 17 were established to be resistant to penicillin (89.5%, and 2 strains to gentamicin

  3. ß-lactamasas AmpC plasmídicas tipo CMY-2 emergentes en Tucumán, Argentina CMY-2-type plasmid-mediated AmpC ß-Lactamases emerging in Tucumán, Argentina

    Directory of Open Access Journals (Sweden)

    María A. Jure

    2011-03-01

    . Susceptibility testing was performed by disk diffusion; one P. mirabilis and three E. coli strains showed resistance to cephamycins (cefoxitin and C3G. An E-test to determine MIC and a synergy test by aminophenylboronic disks were performed. Enzymatic activity against cefoxitin was confirmed by a microbiological assay. A polymerase chain reaction (PCR for the detection of plasmid-mediated ampC genes of different groups was performed and a 462-bp amplicon was obtained when using primers directed against the CIT group; the obtained sequences were compared to blaCMY-2 sequences, showing 100% identity. The emergence of CMY-2-type plasmid-mediated AmpC ß-lactamases indicated the importance of implementing systematic monitoring of these resistances to avoid potential clinical and epidemiological consequences.

  4. Plasmid-mediated AmpC beta-lactamase-producing Escherichia coli causing urinary tract infection in the Auckland community likely to be resistant to commonly prescribed antimicrobials.

    Science.gov (United States)

    Drinkovic, Dragana; Morris, Arthur J; Dyet, Kristin; Bakker, Sarah; Heffernan, Helen

    2015-03-13

    To estimate the prevalence and characterise plasmid-mediated AmpC beta-lactamase (PMACBL)- producing Escherichia coli in the Auckland community. All cefoxitin non-susceptible (NS) E. coli identified at the two Auckland community laboratories between 1 January and 31 August 2011 were referred to ESR for boronic acid double-disc synergy testing, to detect the production of AmpC beta-lactamase, and polymerase chain reaction (PCR) to identify the presence of PMACBL genes. PMACBL-producing isolates were typed using pulsed-field gel electrophoresis (PFGE), and PCR was used to determine their phylogenetic group and to identify multilocus sequence type (ST)131. Antimicrobial susceptibility testing and detection of extended-spectrum beta-lactamases (ESBLs) were performed according to the Clinical and Laboratory Standards Institute recommendations. 101 (51%) and 74 (37%) of 200 non-duplicate cefoxitin-NS E. coli were PMACBL producers or assumed hyper-producers of chromosomal AmpC beta-lactamase, respectively. The prevalence of PMACBL-producing E. coli was 0.4%. PMACBL-producing E. coli were significantly less susceptible to norfloxacin, trimethoprim and nitrofurantoin than E. coli that produced neither a PMACBL nor an ESBL. Very few (4%) PMACBL-producing E. coli co-produced an ESBL. Most (88%) of the PMACBL-producing isolates had a CMY-2-like PMACBL. The PMACBL-producing E. coli isolates were diverse based on their PFGE profiles, 44% belonged to phylogenetic group D, and only four were ST131. 100 of the 101 PMACBL-producing E. coli were cultured from urine, and were causing urinary tract infection (UTI) in the majority of patients. The median patient age was 56 years and most (94%) of the patients were women. A greater proportion of patients with community-acquired UTI caused by PMACBL-producing E. coli received a beta-lactam antimicrobial than patients with community-acquired UTI caused by other non-AmpC, non-ESBL-producing E. coli. Thirty-six (43%) patients with community

  5. Long-Term Evolution Studies of E. Coli under Combined Effects of Simulated Microgravity and Antibiotic.

    Science.gov (United States)

    Karouia, Fathi; Tirumalai, Madhan R.; Ott, Mark C.; Pierson, Duane L.; Fox, George E.; Tran, Quyen

    2016-07-01

    , Cefoxitin and Tetracycline), even after 11 cycles of 'erasure' of the 'adaptation memory' - this 'erasure' was accomplished by re-growing the evolved cells under shaker flask conditions and 1 cycle equals 10 generations. In the case of the cells evolved using heat sterilized HARVs, no resistance was observed to any of the an-tibiotics used (Ampicillin, Amoxicillin/Clavulanic Acid, Piperacillin/Tazobactam, Cefalotin, Cefazolin, Cefuroxime, Cefuroxime Axetil, Cefoxitin, Cefpodox-ime, Ceftazidime, Ceftriaxone, Cefepime, Gentamicin, Tobramycin, Ciprofloxacin, Levofloxacin, Norfloxacin, Tetracycline, Nitrofurantoin, and Trimethoprim/Sulfamethoxazole), even after 1000 generations of growth under LSMMG. Competition experiments using an isogenic pair revealed that the adaptive advantage of the 1000G strain (in both cases) over an unexposed strain was rapidly eliminated. While this obviously implies that the adaptation was primarily environmental rather than genomic, the levels of antibiotic resistance observed to be consistently maintained, raises the concern of persistent resistance conferred to bacterial communities through exposure to antibiotics on space missions. Supported by grants from the Center for Bionanotechnology and Environmental Research at Texas Southern University (NASA Cooperative Agreement NNX08B4A47A).

  6. Inferring the interaction structure of resistance to antimicrobials.

    Science.gov (United States)

    Zawack, Kelson; Love, Will; Lanzas, Cristina; Booth, James G; Gröhn, Yrjö T

    2018-04-01

    The growth of antimicrobial resistance presents a significant threat to human and animal health. Of particular concern is multi-drug resistance, as this increases the chances an infection will be untreatable by any antibiotic. In order to understand multi-drug resistance, it is essential to understand the association between drug resistances. Pairwise associations characterize the connectivity between resistances and are useful in making decisions about courses of treatment, or the design of drug cocktails. Higher-order associations, interactions, which tie together groups of drugs can suggest commonalities in resistance mechanism and lead to their identification. To capture interactions, we apply log-linear models of contingency tables to analyze publically available data on the resistance of Escheresia coli isolated from chicken and turkey meat by the National Antimicrobial Resistance Monitoring System. Standard large sample and conditional exact testing approaches for assessing significance of parameters in these models breakdown due to structured patterns inherent to antimicrobial resistance. To address this, we adopt a Bayesian approach which reveals that E. coli resistance associations can be broken into two subnetworks. The first subnetwork is characterized by a hierarchy of β-lactams which is consistent across the chicken and turkey datasets. Tier one in this hierarchy is a near equivalency between amoxicillin-clavulanic acid, ceftriaxone and cefoxitin. Susceptibility to tier one then implies susceptibility to ceftiofur. The second subnetwork is characterized by more complex interactions between a variety of drug classes that vary between the chicken and turkey datasets. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. In vitro activity of tigecycline against clinical isolates of carbapenem resistant Acinetobacter baumannii complex in Pretoria, South Africa

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    Ahmed Nahid H

    2012-05-01

    Full Text Available Abstract Background The presence of multi-drug resistant Acinetobacter baumannii raises a big therapeutic challenge in our hospital. Tigecycline, a new glycylcycline with expanded broad spectrum of activity against multi-drug resistant organisms was recently licensed in South Africa. Aim The aim of this study was to evaluate the in vitro activity of tigecycline against carbapenem resistant A. baumannii complex. Methods Consecutive clinical isolates of carbapenem resistant A. baumannii complex were collected between February and July 2010. Species identification and susceptibility testing was performed by Vitek-2 colorimetric compact system with Advanced Expert System (AES. Strains were tested for carbapenemase production by the modified Hodge test, according to the Clinical and Laboratory Standards Institute (CLSI guidelines. Results A total of 232 carbapenem resistant clinical isolates of A. baumannii complex were collected over the six months study period; 217 (93.5% of these were modified Hodge test positive. All isolates were susceptible to colistin and 174 (78% susceptible to amikacin whilst 20 (9% were susceptible to ciprofloxacin. For tigecycline 169 (75.8% were fully susceptible, 37 (16.6% intermediately resistant and only 17 (7.6% were fully resistant. None of the carbapenem resistant isolates were susceptible to ampicillin, amoxicillin/clavullanic acid, piperacillin/tazobactam, cefuroxime, cefuroxime axetil, cefoxitin, cefepime or nitrofurantoin. Conclusion All carbapenem resistant isolates were found to be fully susceptible to colistin; amikacin and tigecycline susceptibility was 78% and 76% respectively. Treatment options for infections due to carbapenem and multi-drug resistant A. baumannii organisms are limited and hence tigecycline and amikacin may be considered. The properties of tigecycline i.e. stability, safety, low toxicity, non cross-resistance with other antibiotics and its efficacy against multi-drug resistant A. baumannii

  8. Characterisation of quinolone-resistant Escherichia coli of 1997 and 2005 isolates from poultry in Mexico.

    Science.gov (United States)

    Del Rio-Avila, C; Rosario, C; Arroyo-Escalante, S; Carrillo-Casas, E M; Díaz-Aparicio, E; Suarez-Güemes, F; Silva-Sanchez, J; Xicohtencatl-Cortes, J; Maravilla, P; Hernández-Castro, R

    2016-08-01

    Forty-two enrofloxacin-resistant Escherichia coli strains isolated from eggs and first-week mortality associated with yolk sac infection of two vertically integrated poultry companies of Central Mexico in 1997 and 2005 were characterised. E. coli resistance to 19 antibiotics was determined, as well as the minimum inhibitory concentrations (broth dilution) for ciprofloxacin. The presence of gyrA,B, parC,E chromosomal point mutations, qnrA,B,S plasmid genes and the aminoglycoside acetyltransferase aac(6')-Ib-cr were determined by PCR and sequencing. Resistance to ampicillin (95%), piperacillin (95%), gatifloxacin (95%), levofloxacin (95%), ampicillin/sulbactam (90%), cefazolin (85%), trimethoprim/sulfamethoxazole (80%), amoxicillin/clavulanic acid (80%), aztreonam (80%), cefepime (80%), cefotaxime (80%), ceftazidime (80%), ceftriaxone (80%) and cefoxitin (75%) was high in the 2005 strains and 19 (95%) strains were resistant to 7 or more antimicrobials. The strains from 1997 expressed high rates of resistance only to the fluoroquinolones and 4 strains (18%) expressed resistance to 7 or more antimicrobials. All strains had a gyrA mutation (Ser83Leu) and a parC mutation (Ser80Ile or Ser80Arg) and 41 (97.6%) strains had a second gyrA mutation (Asp87Asn, Asp87Tyr or Asp87Gly). Only two (4.7%) strains had a parE mutation (Ser458Ala). A total of 10 strains were positive for the aac(6')-Ib wild-type gene, 6 strains for the aac(6')-Ib-cr variant and 6 strains possessed both the wild type and the variant. No gyrB mutations or qnrA,B,S genes were detected. This is the first report in Latin America of chromosomal and plasmid quinolone resistance genes in E. coli strains recovered from poultry.

  9. PREDISPOSING FACTORS AND AETIOLOGY OF URINARY TRACT INFECTIONS IN PREGNANT WOMEN

    Directory of Open Access Journals (Sweden)

    Prem Prakash

    2016-06-01

    Full Text Available BACKGROUND Urinary tract infection (UTI is a common infection in pregnant women. It is responsible for range of complications causing perinatal and maternal morbidity and mortality. AIM To assess the associated risk factors, aetiology and their antibiogram of UTI among pregnant women. METHODOLOGY This is a cross-sectional study carried out in Department of Microbiology & Department of Obstetrics from March 2015 to February 2016. The patient details and risk factors were recorded. Midstream & catheter urine specimens from pregnant women with symptoms of UTI were collected and sent for routine microscopy, culture and sensitivity. RESULTS In 550 pregnant women, 122(22.18% had significant bacteriuria and 72(17.72% had low colony count UTI. The most affected number age group was 25-35 years (58.85% followed by 15-25 years. Of the associated risk factors, multiparity 45.31%, low socioeconomic status 42.18%, anaemia 39.06% etc. were important. Escherichia coli was most frequently isolated with a percentage of 29.14%, followed by Klebsiella species (17.49%, S. aureus (14.34% etc. Other isolated micro-organisms included Enterococci, Proteus mirabilis, Citrobacter, Pseudomonas, Acinetobacter species. The antibiotics with more than 50% sensitivity against Gram-negative isolates were Imipenem (74.7%, Levofloxacin (73.17%, Ciprofloxacin (69.10%, Amikacin (57.72%, Amoxiclav (55.28%, and Cefoperazone/Sulbactam (50.40%. The antibiotics for Gram-positive isolates were Linezolid (88.46%, Cefoxitin (78.84%, Teicoplanin (69.23% and Vancomycin (65.22%. CONCLUSION We found associated risk factors such as multiparity, low socioeconomic status, etc. E. coli was the most common bacteria isolated in our setting. Therefore, pregnant women should be assessed for associated risk factors and evaluated for the pathogenic organism during their regular follow-up. The drug sensitivity should be taken into consideration with their side effects related to pregnancy.

  10. Biofilm production and beta-lactamic resistance in Brazilian Staphylococcus aureus isolates from bovine mastitis

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    Viviane Figueira Marques

    Full Text Available Abstract Staphylococcus spp. play an important role in the etiology of bovine mastitis. Staphylococcus aureus is considered the most relevant species due to the production of virulence factors such as slime, which is required for biofilm formation. This study aimed to evaluate biofilm production and its possible relation to beta-lactamic resistance in 20 S. aureus isolates from bovine mastitic milk. The isolates were characterized by pheno-genotypic and MALDI TOF-MS assays and tested for genes such as icaA, icaD, bap, agr RNAIII, agr I, agr II, agr III, and agr IV, which are related to slime production and its regulation. Biofilm production in microplates was evaluated considering the intervals determined along the bacterial growth curve. In addition, to determine the most suitable time interval for biofilm analysis, scanning electron microscopy was performed. Furthermore, genes such as mecA and blaZ that are related to beta-lactamic resistance and oxacillin susceptibility were tested. All the studied isolates were biofilm producers and mostly presented icaA and icaD. The Agr type II genes were significantly prevalent. According to the SEM, gradual changes in the bacterial arrangement were observed during biofilm formation along the growth curve phases, and the peak was reached at the stationary phase. In this study, the penicillin resistance was related to the production of beta-lactamase, and the high minimal bactericidal concentration for cefoxitin was possibly associated with biofilm protection. Therefore, further studies are warranted to better understand biofilm formation, possibly contributing to our knowledge about bacterial resistance in vivo.

  11. Molecular epidemiology and antimicrobial resistance of Salmonella typhimurium DTI04 on Ontario swine farms.

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    Farzan, Abdolvahab; Friendship, Robert M; Poppe, Cornelis; Martin, Laura; Dewey, Catherine E; Funk, Julie

    2008-01-01

    This study was conducted to examine antimicrobial resistances, plasmid profiles, and pulsed-field gel electrophoresis patterns of 80 Salmonella Typhimurium (including var. Copenhagen) DT104 strains (including DT104a and DT104b) recovered from pig and environmental fecal samples on 17 swine farms in Ontario. No resistance was observed to amoxicillin/clavulanic acid, apramycin, carbadox, cephalothin, ceftriaxone, ceftiofur, cefoxitin, ciprofloxacin, nalidixic acid, trimethoprim, and tobramycin. However, the isolates exhibited resistance against 4 to 10 antimicrobials with the most frequent resistance being to sulfonamides (Su), ampicillin (A), streptomycin (S), spectinomycin (Sp), chloramphenicol (C), tetracycline (T), and florfenicol (F). Thirteen distinct resistance patterns were determined but 88% of isolates shared the typical resistance pattern "ACSpSSuT." Twelve different plasmid profiles were observed; the 62 MDa virulence-associated plasmid was detected in 95% of the isolates. The 2.1 MDa plasmid was the second most frequent one, which was harbored by 65% isolates. The isolates were classified into 23 distinct genotypes by PFGE-SpeI + BlnI when difference in at least one fragment was defined as a distinct genotype. In total, 39 distinct "types" were observed when defining a "type" based on the combination of antimicrobial resistance, plasmid pattern, and PFGE-SpeI + BlnI for each isolate. The highest diversity was 0.96 (95% CI: 0.92, 0.96) for the "type" described above followed by 0.92 (95% CI: 0.88, 0.93) for PFGE-SpeI + BlnI. The diversity of DT104 isolates indicates there might be multiple sources for this microorganism on swine farms. This knowledge might be used to track these sources, as well as to study the extent of human salmonellosis attributed to pork compared to food products derived from other food-producing animals.

  12. 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

  13. Antibiotic resistance in bacteria Staphylococcus spp. isolated from samples of raw sheep's milk

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    Milan Vasiľ

    2016-12-01

    Full Text Available From samples of raw sheep's milk were determined results of bacteriological examination from two herds in region of Eastern Slovakia in three years lasting study. The occurrence of Staphylococcus spp. 41.6% (124 was determined from 298 samples. The seven species of staphylococci were on a regular basis isolated: S. epidermidis (34, S. chromogenes (26, S. aureus (16. Alternately have been recorded S. warneri (16, S. schleiferi (15, S. haemolyticus (9 and S. xylosus (8. All isolated pathogens were tested by in vitro test on Mueller-Hinton agar by disc methods on resistance to 10 types of antibiotics.  Highest value of resistance was determined to Penicilin 21.0%, Neomycin 10.5% and Novobiocin 9.7%. Lower resistance was in to Oxacilin 7.2% and Amoxicilin 6.5%. Minimal resistance was founded to Cefoxitin 0.8%, Linkomycin 2.4%, Erytromycin, and Streptomycin 3.2%. Was founded total resistance (21.0% to all antibiotics in S. epidermidis (34 during the three years, S. chromogenes (26 showed resistance to 8 types of antibiotics (12.9%, S. aureus (16 to 6 antibiotics (10.5% and S. warneri (16 to 4 antibiotics (5.6%. It was confirmed that sheep's milk remains a major source of staphylococci. Bacteria in comparison with isolates from cows' raw milk, showed lower values of resistance, but were resistant to more than two antibiotics. Recorded occurrence of resistance in staphylococci may be connected with a minimum use of antibiotics in the treatment of mastitis and other diseases in sheep herds. Reported resistance to the tested antibiotics became the basis for the recommendation to use preparations to treat mastitis in sheep principally by the detection of resistance to antibiotics contained.

  14. 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.

  15. 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.

  16. 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.

  17. [Bacterial colangitis: therapeutic features

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    Russo, M.; Carmellino, S.; Russo, G.

    1999-01-01

    Cholangitis results from the combination of bactibilia and biliary tract obstruction. In recent years considerable progress has been made in the diagnosis and treatment of cholangitis; advances in endoscopic techniques and antibiotic therapy have ameliorated the prognosis of cholangitis. The choice of an antimicrobial regimen for cholangitis should take into account the antibiotic sensitivities of bacteria colonizing biliary tree, the antibiotic excretion into bile and whether biliary obstruction or bacteremia is present. Successful treatment depends on relieving biliary obstruction and administering antibiotics effective against bacteria implicated. The initial therapy should be active against E. coli and Klebsiella spp., while it is controversial whether the empirical antibiotic regimen should also include coverage against Enterococcus, Pseudomonas and anaerobes. The ureidopenicillins are the preferred initial treatment; the combination piperacillin-tazobactam may be active against the resistant species. Second generation cephalosporins like cefamandole and cefoxitin are still useful, cefoperazone gives excellent coverage against gram-negative bacteria, while cefepime may be suitable as treatment for acute cholangitis. In severe cholangitis an aminoglycoside can be added to the beta-lactamin; once-daily aminoglycoside administration is associated with a reduced incidence of nephrotoxicity also in patients with cholestasis. Whether the fluoroquinolones are effective in treatment for cholangitis has not been fully evaluated. In patients with suppurative cholangitis prompt endoscopic drainage is mandatory, since antibiotics alone will not sterilize the biliary tract in the face of obstruction. Antibiotic prophylaxis to prevent cholangitis after ERCP should be administered particularly to patients in whom biliary drainage is expected to be difficult; antimicrobial prophylaxis with piperacillin effectively prevents ERCPinduced cholangitis. Antibiotic maintenance

  18. Genomic relatedness of Staphylococcus pettenkoferi isolates of different origins.

    Science.gov (United States)

    Månsson, Emeli; Hellmark, Bengt; Stegger, Marc; Skytt Andersen, Paal; Sundqvist, Martin; Söderquist, Bo

    2017-05-01

    The aim of the study was to characterize clinical and environmental Staphylococcus pettenkoferi isolates with regard to genomic diversity and antibiotic susceptibility pattern. Repetitive-sequence-based PCR and core genome phylogenetic analysis of whole-genome sequencing (WGS) data verified the presence of distinct clades comprising closely related S. pettenkoferi isolates from different geographical locations and origins. Phylogenetic relationships between 25 S. pettenkoferi isolates collected from blood cultures and intra-operative air sampling were determined by repetitive-sequence-based PCR typing and analysis of ~157 000 SNPs identified in the core genome after WGS. Antibiotic susceptibility testing and tests for biofilm production (microtitre plate assay) were performed. Repetitive-sequence-based PCR as well as WGS data demonstrated the close relatedness of clinically significant blood culture isolates to probable contaminants, as well as to environmental isolates. Antibiotic-susceptibility testing demonstrated a low level of antimicrobial resistance. The mecA gene was present in two cefoxitin-resistant isolates. No isolates were found to produce biofilm. Close genomic relatedness of S. pettenkoferi isolates from different geographical locations and origins were found within clades, but with substantial genomic difference between the two major clades. The ecological niche of S. pettenkoferi remains unconfirmed, but the presence of S. pettenkoferi in the air of the operating field favours the suggestion of a role in skin flora. Identification of S. pettenkoferi in clinical samples should, in a majority of cases, most likely be regarded as a probable contamination, and its role as a possible pathogen in immunocompromised hosts remains to be clarified.

  19. First Report in China on the Identification and Drug Sensitivity of Mycobacterium elephantis Isolated from the Milk of a Cow with Mastitis.

    Science.gov (United States)

    Ji, Ling Yun; Xu, Dong Lei; Yin, Shu Peng; Liu, Hai Can; Li, Gui Lian; Jiang, Yi; Wei, Jian Hao; Zeng, Hao; Lou, Yong Liang; Lyu, Jian Xin; Wan, Kang Lin

    2017-07-01

    In this study, milk from a cow with mastitis was analyzed to determine the presence of mycobacterial infection. Milk quality and security problems pertaining to the safe consumption of dairy products were also discussed in this study. Milk was preprocessed with 4% NaOH. Then, mycobacteria were isolated from the milk sample on L-J medium. The isolate was identified using multiple loci Polymerase Chain Reaction (PCR) and multi-locus sequence analysis with 16S rRNA, sodA, hsp65, and ITS genes. The drug sensitivity of the isolate to 27 antibiotics was tested through alamar blue assay. Smooth, moist, pale yellow colonies appeared on the L-J medium within a week after inoculation. Based on the results of multiple loci PCR analysis, the isolate was preliminarily identified as non-tuberculous mycobacteria. The 16S rRNA, SodA, hsp65, and ITS gene sequences of the isolate exhibited 99%, 99%, 99%, and 100% similarities, respectively, with those of the published reference strains of Mycobacterium elephantis (M. elephantis). The drug sensitivity results showed that the strain is resistant to isoniazid, p-aminosalicylic acid, and trimesulf but is sensitive to ofloxacin, rifampicin, amikacin, capreomycin, moxifloxacin, kanamycin, levofloxacin, cycloserine, ethambutol, streptomycin, tobramycin, rifabutin, ciprofloxacin, linezolid, cefoxitin, clarithromycin, and minocycline. To the best of our knowledge, this study is initially to report the isolation of M. elephantis from the milk of a cow with mastitis in China. Copyright © 2017 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

  20. Mycobacterium grossiae sp. nov., a rapidly growing, scotochromogenic species isolated from human clinical respiratory and blood culture specimens.

    Science.gov (United States)

    Paniz-Mondolfi, Alberto Enrique; Greninger, Alexander L; Ladutko, Lynn; Brown-Elliott, Barbara A; Vasireddy, Ravikiran; Jakubiec, Wesley; Vasireddy, Sruthi; Wallace, Richard J; Simmon, Keith E; Dunn, Bruce E; Jackoway, Gary; Vora, Surabhi B; Quinn, Kevin K; Qin, Xuan; Campbell, Sheldon

    2017-11-01

    A previously undescribed, rapidly growing, scotochromogenic species of the genus Mycobacterium (represented by strains PB739 T and GK) was isolated from two clinical sources - the sputum of a 76-year-old patient with severe chronic obstructive pulmonary disease, history of tuberculosis exposure and Mycobacterium avium complex isolated years prior; and the blood of a 15-year-old male with B-cell acute lymphoblastic leukaemia status post bone marrow transplant. The isolates grew as dark orange colonies at 25-37 °C after 5 days, sharing features in common with other closely related species. Analysis of the complete 16S rRNA gene sequence (1492 bp) of strain PB739 T demonstrated that the isolate shared 98.8 % relatedness with Mycobacterium wolinskyi. Partial 429 bp hsp65 and 744 bp rpoB region V sequence analyses revealed that the sequences of the novel isolate shared 94.8 and 92.1 % similarity with those of Mycobacterium neoaurum and Mycobacterium aurum, respectively. Biochemical profiling, antimicrobial susceptibility testing, HPLC/gas-liquid chromatography analyses and multilocus sequence typing support the taxonomic status of these isolates (PB739 T and GK) as representatives of a novel species. Both isolates were susceptible to the Clinical and Laboratory Standards Institute recommended antimicrobials for susceptibility testing of rapidly growing mycobacteria including amikacin, ciprofloxacin, moxifloxacin, doxycycline/minocycline, imipenem, linezolid, clarithromycin and trimethropin/sulfamethoxazole. Both isolates PB739 T and GK showed intermediate susceptibility to cefoxitin. We propose the name Mycobacterium grossiae sp. nov. for this novel species and have deposited the type strain in the DSMZ and CIP culture collections. The type strain is PB739 T (=DSM 104744 T =CIP 111318 T ).

  1. Characterization of blaCTX gene and Cross-resistance in Klebsiella pneumoniae Isolated from Hospitalized Patients

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    Gholamreza Pourali Sheshblouki

    2016-04-01

    Full Text Available Background and Aim: Klebsiella pneumoniae is a member of the Enterobacteriaceae family. There is a global emergence of multidrug-resistant (MDR strains of K. pneumoniae, a Gram-negative enteric bacterium that causes nosocomial and urinary tract infections. The aims of the present study were to identify the Klebsiella pneumoniae infections in hospitalized patients, characterization of blaCTX gene, detection cross-resistance and cefepime susceptible-dose dependent (SDD in isolates. Materials and Methods: In present study, 111 strains of Klebsiella pneumoniae were isolated from patients hospitalized in Ghotbadden, Faghihi and Nemazee hospitals (Shiraz, Iran. The isolates were identified as K.pneumoniae, based on biochemical tests embedded in the API-20E system. Susceptibility testing (disc diffusion was performed according clinical and laboratory standards institute (CLSI guidelines. Detection cefepime susceptible-dose dependent (SDD was performed. The detection of AmpC β-lactamases producing strains was done based on cefoxitin and cefepime disk tests. The blaCTX gene was detected in the isolates by PCR molecular method. Results: Total 111 Klebsiella pneumoniae isolates were studied. The less effective drug was ceftazidime (37.8% isolates were sensitive. All SDD strains were susceptible to colistin and imipenem. Colistin (96.4% and imipenem (88.3% were the most effective antibiotics against isolates. Respectively, 41.4% and 35.1% isolates displayed resistance to gentamicin and amikacin. All colistin resistant isolates were imipenem sensitive. The results of PCR on blaCTX gene showed that 70.3% of the isolates possess the gene. Conclusion: Carbapenem drugs are effective against Klebsieella pneumoniae infections. These results indicate that multidrug-resistant (MDR and extensively drug resistant (XDR strains of K.pneumoniae are rising, and fewer antibiotics may be useful for treating infections caused by these strains. Routine investigation and

  2. In vivo selection of resistant E. coli after ingestion of milk with added drug residues.

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    Pereira, Richard Van Vleck; Siler, Julie D; Bicalho, Rodrigo Carvalho; Warnick, Lorin D

    2014-01-01

    Antimicrobial resistance represents a major global threat to modern medicine. In vitro studies have shown that very low concentrations of drugs, as frequently identified in the environment, and in foods and water for human and animal consumption, can select for resistant bacteria. However, limited information is currently available on the in vivo impact of ingested drug residues. The objective of our study was to evaluate the effect of feeding preweaned calves milk containing antimicrobial drug residues (below the minimum inhibitory concentration), similar to concentrations detected in milk commonly fed to dairy calves, on selection of resistant fecal E. coli in calves from birth to weaning. At birth, thirty calves were randomly assigned to a controlled feeding trial where: 15 calves were fed raw milk with no drug residues (NR), and 15 calves were fed raw milk with drug residues (DR) by adding ceftiofur, penicillin, ampicillin, and oxytetracycline at final concentrations in the milk of 0.1, 0.005, 0.01, and 0.3 µg/ml, respectively. Fecal samples were rectally collected from each calf once a week starting at birth prior to the first feeding in the trial (pre-treatment) until 6 weeks of age. A significantly greater proportion of E. coli resistant to ampicillin, cefoxitin, ceftiofur, streptomycin and tetracycline was observed in DR calves when compared to NR calves. Additionally, isolates from DR calves had a significant decrease in susceptibility to ceftriaxone and ceftiofur when compared to isolates from NR calves. A greater proportion of E. coli isolates from calves in the DR group were resistant to 3 or more antimicrobial drugs when compared to calves in the ND group. These findings highlight the role that low concentrations of antimicrobial drugs have on the evolution and selection of resistance to multiple antimicrobial drugs in vivo.

  3. In vivo selection of resistant E. coli after ingestion of milk with added drug residues.

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    Richard Van Vleck Pereira

    Full Text Available Antimicrobial resistance represents a major global threat to modern medicine. In vitro studies have shown that very low concentrations of drugs, as frequently identified in the environment, and in foods and water for human and animal consumption, can select for resistant bacteria. However, limited information is currently available on the in vivo impact of ingested drug residues. The objective of our study was to evaluate the effect of feeding preweaned calves milk containing antimicrobial drug residues (below the minimum inhibitory concentration, similar to concentrations detected in milk commonly fed to dairy calves, on selection of resistant fecal E. coli in calves from birth to weaning. At birth, thirty calves were randomly assigned to a controlled feeding trial where: 15 calves were fed raw milk with no drug residues (NR, and 15 calves were fed raw milk with drug residues (DR by adding ceftiofur, penicillin, ampicillin, and oxytetracycline at final concentrations in the milk of 0.1, 0.005, 0.01, and 0.3 µg/ml, respectively. Fecal samples were rectally collected from each calf once a week starting at birth prior to the first feeding in the trial (pre-treatment until 6 weeks of age. A significantly greater proportion of E. coli resistant to ampicillin, cefoxitin, ceftiofur, streptomycin and tetracycline was observed in DR calves when compared to NR calves. Additionally, isolates from DR calves had a significant decrease in susceptibility to ceftriaxone and ceftiofur when compared to isolates from NR calves. A greater proportion of E. coli isolates from calves in the DR group were resistant to 3 or more antimicrobial drugs when compared to calves in the ND group. These findings highlight the role that low concentrations of antimicrobial drugs have on the evolution and selection of resistance to multiple antimicrobial drugs in vivo.

  4. Genomic Analysis of Third Generation Cephalosporin Resistant Escherichia coli from Dairy Cow Manure

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    Muhammad Attiq Rehman

    2017-11-01

    Full Text Available The production of extended-spectrum β-lactamases (ESBLs conferring resistance to new derivatives of β-lactams is a major public health threat if present in pathogenic Gram-negative bacteria. The objective of this study was to characterize ceftiofur (TIO- or cefotaxime (FOX-resistant Escherichia coli isolated from dairy cow manure. Twenty-four manure samples were collected from four farms and incubated under anaerobic conditions for 20 weeks at 4 °C or at 25 °C. A total of 37 TIO- or FOX-resistant E. coli were isolated from two of the four farms to determine their susceptibility to 14 antibiotics. Among the 37 resistant E. coli, 10 different serotypes were identified, with O8:H1 being the predominant serotype (n = 17. Five isolates belonged to each of serotypes O9:NM and O153:H42, respectively. All 37 cephalosporin resistant isolates were multi-resistant with the most prevalent resistance spectrum being amoxicillin-clavulanic acid-ampicillin-cefoxitin-ceftiofur-ceftriaxone-chloramphenicol-streptomycin-sulfisoxazole-tetracycline-trimethoprim-sulfamethoxazole. The genomes of 18 selected isolates were then sequenced and compared to 14 selected human pathogenic E. coli reference genomes obtained from public repositories using different bioinformatics approaches. As expected, all 18 sequenced isolates carried at least one β-lactamase bla gene: TEM-1, TEM-81, CTX-M115, CTX-M15, OXA-1, or CMY-2. Several other antibiotic resistance genes (ARGs and virulence determinants were detected in the sequenced isolates and all of them harbored antimicrobial resistance plasmids belonging to classic Inc groups. Our results confirm the presence of diverse ESBL producing E. coli isolates in dairy cow manure stored for a short period of time. Such manure might constitute a reservoir of resistance and virulence genes for other bacteria that share the same environment.

  5. The effect of hospital effluent on antimicrobial resistant E. coli within a municipal wastewater system.

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    Harris, S; Morris, C; Morris, D; Cormican, M; Cummins, E

    2013-03-01

    There is a concern that hospital effluent potentially containing antimicrobial compounds, antimicrobial resistant (AMR) bacteria and genetic determinants of resistance may contribute to the emergence, dissemination and persistence of AMR bacteria in municipal wastewaters. Hence, it is of interest to investigate the effect, if any, hospital effluent has on the percentage of AMR bacteria within wastewater. Water from two wastewater treatment plants (WWTPs) (one receives and treats hospital effluent (WWTPhe) and the second does not (WWTPc)) were examined for E. coli expressing resistance to seven antimicrobials (ampicillin, streptomycin, cefoxitin, cefotaxime, tetracycline, sulphonamide and ciprofloxacin). A two-sample t-test showed that AMR E. coli are present in WWTP influent and effluent, irrespective of receiving hospital effluent, and are being released into the environment (no statistical difference in count between the two WWTPs). The effect of hospital effluent on resistance varies for each AMR bacteria. Excluding tetracycline, sulphonamide and ciprofloxacin, the results suggest that the release of hospital effluent does not significantly affect the frequency with which AMR E. coli are detected in effluent. For some hospital specific antimicrobial agents, such as ciprofloxacin, the release of hospital effluent is associated with an increased proportion of antimicrobial resistance. The results suggest resistance to AMR E. coli may already be well developed in the community, making the effect of hospital effluent on AMR E. coli indistinguishable. However, for hospital specific antimicrobials, there may be a selective effect and hence limiting the release of hospital effluent containing such antimicrobials may impact the proportion of antimicrobial resistance. This research has provided statistical evidence to support necessary mitigation and remediation of antimicrobial residue release and subsequent resistance in the environment.

  6. An Investigation of the Prevalence of AmpC-producing Pseudomonas aeruginosa in Clinical Samples in Zahedan City, Iran

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    Javad Adabi

    2017-06-01

    Full Text Available Background and Objectives: AmpC beta-lactamases are among cephalosporinases encoded on the chromosomes of many Enterobacteriaceae. In many bacteria, induction of AmpC enzymes can be made at a very high level by numerous mutations. In this study, the prevalence of chromosomal AmpC genes, was investigated in the isolates of Pseudomonas aeruginosa isolated from teaching hospitals in Zahedan city in 2015. Methods: In this descriptive cross-sectional study, 100 P. aeruginosa isolates were isolated from 391 clinical samples using biochemical and conventional methods. cefoxitin (30μg disk diffusion method was used to isolate AmpC-producing strains, and multiplex PCR was used to identify chromosomal AmpC genes. ESBL containing strains was assessed using ceftazidime (30μg and cefotaxime/clavulanic acid (30μg/10μg disk diffusion tests. Data analysis was performed using χ2 test. Results: In primary phenotypic screening, out of 100 P. aeruginosa isolated, 88 isolates were ESBL producers and 20 isolates (20% were AmpC beta-lactamase producers. Among 20 phenotypically identified AmpC producing isolates, 19 isolates (95% had FOX gene, 7 isolates (35% had EBC gene, 4 isolates (20% had ACC gene, and 15 isolates isolates (75% had DHA gene, which were detected by multiPlex PCR assay. Conclusion: The results of the present study indicated that the presence of AmpC leads to resistance of bacteria to many cephalosporins. Also, use of multiplex PCR yields the best results in the group identification of these genes.

  7. Staphylococcus aureus ST6-t701 isolates from food-poisoning outbreaks (2006-2013) in Xi'an, China.

    Science.gov (United States)

    Li, Guanghui; Wu, Shouzhi; Luo, Wen; Su, Yulan; Luan, Yang; Wang, Xin

    2015-03-01

    The aim of the study was to investigate the molecular epidemiologic of Staphylococcus aureus isolated from seven staphylococcal food-poisoning (SFP) outbreaks between 2006 and 2013 in Xi'an, northwest China. A total of seven S. aureus isolates associated with seven SFP outbreaks were obtained and characterized by determining the multilocus sequence typing, spa typing, pulsed-field gel electrophoresis (PFGE), antimicrobial susceptibility, toxin and resistant genes. The results showed that S. aureus ST6-t701 (71.4%) was the most predominant clone, followed by ST5-t002 and ST59-t172 (each 14.3%). Seven different PFGE patterns were obtained. Moreover, resistance was most frequently observed to trimethoprim and penicillin (each 71.4%), followed by erythromycin (28.6%), ampicillin, clindamycin, and tetracycline (each 14.3%). All strains were susceptible to chloramphenicol, cefoxitin, oxacillin, amikacin, and vancomycin. Three of seven strains displayed resistance to three or more antimicrobials. Resistance genes were found as follows: linA/linA' (100%), blaZ (85.7%), tet(K), ermC, ermT, and ermB (each 14.3%). Other resistant genes were not detected. In addition, the most frequently identified exotoxin genes were seu, lukED, hla, hlb, hld (each 100%), followed by hlg and hlgv (each 85.7%), lukPV (71.4%), sea (57.1%), see (42.9%), etd (28.6%), and seb, sec, sed, sej, and sek (each 14.3%). The results indicated that S. aureus ST6-t701, with a high prevalence in the northwest of China, exhibited multidrug resistance and harbored multiple toxin and resistance genes. Therefore, strict hygienic and preventative measures should be taken in order to avoid the contamination of food by S. aureus and toxin production in foods.

  8. Chronological Change of Resistance to β-Lactams in Salmonella enterica serovar Infantis Isolated from Broilers in Japan.

    Science.gov (United States)

    Chuma, Takehisa; Miyasako, Daisuke; Dahshan, Hesham; Takayama, Tomoko; Nakamoto, Yuko; Shahada, Francis; Akiba, Masato; Okamoto, Karoku

    2013-01-01

    Epidemiologic surveillance study was conducted in southern Japan to determine the antimicrobial resistance phenotypes and characterize the β-lactamase genes and the plasmids harboring these genes in Salmonella enterica serovar Infantis (S. Infantis) isolates from broilers. Between January, 2007 and December, 2008, a total of 1,472 fecal samples were collected and examined at the Laboratory of Veterinary Public Health, Kagoshima University, Japan. In 93 (6.3%) isolates recovered, 33 (35.5%) isolates showed resistance to cefotaxime, an extended-spectrum cephalosporin (ESC), conferred by TEM-20, TEM-52 and CTX-M-25 extended-spectrum β-lactamases (ESBLs). In addition to ESC-resistance, eight (8.6%) isolates exhibited resistance to cefoxitin mediated by CMY-2 AmpC β-lactamase. Plasmid analysis and polymerase chain reaction replicon typing revealed the bla TEM-20 and bla CMY-2 genes were associated with IncP plasmids, bla TEM-52 was linked with a non-typable plasmid and bla CTX-M-25 was carried by an IncA/C plasmid. Non-β-lactam resistance to streptomycin, sulfamethoxazole, and oxytetracycline encoded by the aadA1, sul1, and tet(A) genes, respectively, was found in 86 (92.5%) isolates. Resistance to kanamycin and ofloxacin was exhibited in 12 (12.9%) and 11 (11.8%) isolates, respectively, the former was mediated by aphA1-Iab. These data indicate that S. Infantis isolates producing ESBLs and AmpC β-lactamase have spread among broiler farms in Japan. These data demonstrated that the incidence of ESC-resistant S. Infantis carrying bla TEM-52 remarkably increased and S. Infantis strains harboring bla CMY-2, bla TEM-20, or bla CTX-M-25 genes emerged from broilers in Japan for the first time in 2007 and 2008.

  9. In vitro activity of ivermectin against Staphylococcus aureus clinical isolates

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    Shoaib Ashraf

    2018-02-01

    Full Text Available Abstract Background Ivermectin is an endectocide against many parasites. Though being a macrocyclic lactone, its activity against bacteria has been less known, possibly due to the fact that micromolar concentrations at tissue levels are required to achieve a therapeutic effect. Among pathogenic bacteria of major medical significance, Staphylococcus aureus cause a number of diseases in a wide variety of hosts including humans and animals. It has been attributed as one of the most pathogenic organisms. The emergence of methicillin resistance has made the treatment of S. aureus even more difficult as it is now resistant to most of the available antibiotics. Thus, search for alternate anti-staphylococcal agents requires immediate attention. Methods Twenty-one clinical isolates of S. aureus were isolated from bovine milk collected from Lahore and Faisalabad Pakistan. Different anthelmintics including levamisole, albendazole and ivermectin were tested against S. aureus to determine their minimum inhibitory concentrations. This was followed-up by growth curve analysis, spot assay and time-kill kinetics. Results The results showed that ivermectin but not levamisole or albendazole exhibited a potent anti-staphylococcal activity at the concentrations of 6.25 and 12.5 μg/ml against two isolates. Interestingly, one of the isolate was sensitive while the other was resistant to methicillin/cefoxitin. Conclusions Our novel findings indicate that ivermectin has an anti-bacterial effect against certain S. aureus isolates. However, to comprehend why ivermectin did not inhibit the growth of all Staphylococci needs further investigation. Nevertheless, we have extended the broad range of known pharmacological effects of ivermectin. As pharmacology and toxicology of ivermectin are well known, its further development as an anti-staphylococcal agent is potentially appealing.

  10. Prevalence of Salmonella enterica, Listeria monocytogenes, and pathogenic Escherichia coli in bulk tank milk and milk filters from US dairy operations in the National Animal Health Monitoring System Dairy 2014 study.

    Science.gov (United States)

    Sonnier, Jakeitha L; Karns, Jeffrey S; Lombard, Jason E; Kopral, Christine A; Haley, Bradd J; Kim, Seon-Woo; Van Kessel, Jo Ann S

    2018-03-01

    The dairy farm environment is a well-documented reservoir for zoonotic pathogens such as Salmonella enterica, Shiga-toxigenic Escherichia coli, and Listeria monocytogenes, and humans may be exposed to these pathogens via consumption of unpasteurized milk and dairy products. As part of the National Animal Health Monitoring System Dairy 2014 study, bulk tank milk (BTM, n = 234) and milk filters (n = 254) were collected from a total of 234 dairy operations in 17 major dairy states and analyzed for the presence of these pathogens. The invA gene was detected in samples from 18.5% of operations and Salmonella enterica was isolated from 18.0% of operations. Salmonella Dublin was detected in 0.7% of operations. Sixteen Salmonella serotypes were isolated, and the most common serotypes were Cerro, Montevideo, and Newport. Representative Salmonella isolates (n = 137) were tested against a panel of 14 antimicrobials. Most (85%) were pansusceptible; the remaining were resistant to 1 to 9 antimicrobials, and within the resistant strains the most common profile was resistance to ampicillin/clavulanic acid, ampicillin, cefoxitin, ceftiofur, ceftriaxone, chloramphenicol, streptomycin, sulfisoxazole, and tetracycline. Listeria spp. were isolated from 19.9% of operations, and L. monocytogenes was isolated from 3.0% of operations. Serogroups 1/2a and 1/2b were the most common, followed by 4b and 4a. One or more E. coli virulence genes were detected in the BTM from 30.5% of operations and in the filters from 75.3% of operations. A combination of stx 2 , eaeA, and γ-tir genes was detected in the BTM from 0.5% of operations and in the filters from 6.6% of operations. The results of this study indicate an appreciable prevalence of bacterial pathogens in BTM and filters, including serovars known to infect humans. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  11. Antimicrobial susceptibility of clinical isolates of anaerobic bacteria in Ontario, 2010-2011.

    Science.gov (United States)

    Marchand-Austin, Alex; Rawte, Prasad; Toye, Baldwin; Jamieson, Frances B; Farrell, David J; Patel, Samir N

    2014-08-01

    The local epidemiology of antimicrobial susceptibility patterns in anaerobic bacteria is important in guiding the empiric treatment of infections. However, susceptibility data are very limited on anaerobic organisms, particularly among non-Bacteroides organisms. To determine susceptibility profiles of clinically-significant anaerobic bacteria in Ontario Canada, anaerobic isolates from sterile sites submitted to Public Health Ontario Laboratory (PHOL) for identification and susceptibility testing were included in this study. Using the E-test method, isolates were tested for various antimicrobials including, penicillin, cefoxitin, clindamycin, meropenem, piperacillin-tazobactam and metronidazole. The MIC results were interpreted based on guidelines published by Clinical and Laboratory Standards Institute. Of 2527 anaerobic isolates submitted to PHOL, 1412 were either from sterile sites or bronchial lavage, and underwent susceptibility testing. Among Bacteroides fragilis, 98.2%, 24.7%, 1.6%, and 1.2% were resistant to penicillin, clindamycin, piperacillin-tazobactam, and metronidazole, respectively. Clostridium perfringens was universally susceptible to penicillin, piperacillin-tazobactam, and meropenem, whereas 14.2% of other Clostridium spp. were resistant to penicillin. Among Gram-positive anaerobes, Actinomyces spp., Parvimonas micra and Propionibacterium spp. were universally susceptible to β-lactams. Eggerthella spp., Collinsella spp., and Eubacterium spp. showed variable resistance to penicillin. Among Gram-negative anaerobes, Fusobacterium spp., Prevotella spp., and Veillonella spp. showed high resistance to penicillin but were universally susceptible to meropenem and piperacillin-tazobactam. The detection of metronidazole resistant B. fragilis is concerning as occurrence of these isolates is extremely rare. These data highlight the importance of ongoing surveillance to provide clinically relevant information to clinicians for empiric management of

  12. Anaerobic bacteria colonizing the lower airways in lung cancer patients

    Directory of Open Access Journals (Sweden)

    Anna Malm

    2011-07-01

    Full Text Available Anaerobes comprise most of the endogenous oropharyngeal microflora, and can cause infections of airways in lung cancer patients who are at high risk for respiratory tract infections. The aim of this study was to determine the frequency and species diversity of anaerobes in specimens from the lower airways of lung cancer patients. Sensitivity of the isolates to conventional antimicrobial agents used in anaerobe therapy was assessed. Respiratory secretions obtained by bronchoscopy from 30 lung cancer patients were cultured onto Wilkins- -Chalgren agar in anaerobic conditions at 37°C for 72–96 hours. The isolates were identified using microtest Api 20A. The minimal inhibitory concentrations for penicillin G, amoxicillin/clavulanate, piperacillin/tazobactam, cefoxitin, imipenem, clindamycin, and metronidazole were determined by E-test. A total of 47 isolates of anaerobic bacteria were detected in 22 (73.3% specimens. More than one species of anaerobe was found in 16 (53.3% samples. The most frequently isolated were Actinomyces spp. and Peptostreptococcus spp., followed by Eubacterium lentum, Veillonella parvula, Prevotella spp., Bacteroides spp., Lactobacillus jensenii. Among antibiotics used in the study amoxicillin/clavulanate and imipenem were the most active in vitro (0% and 2% resistant strains, respectively. The highest resistance rate was found for penicillin G and metronidazole (36% and 38% resistant strains, respectively. The results obtained confirm the need to conduct analyses of anaerobic microflora colonizing the lower respiratory tract in patients with lung cancer to monitor potential etiologic factors of airways infections, as well as to propose efficient, empirical therapy. (Folia Histochemica et Cytobiologica 2011; Vol. 49, No. 2, pp. 263–266

  13. Prevalence of Methicillin-Resistant Staphylococcus aureus from Equine Nasopharyngeal and Guttural Pouch Wash Samples.

    Science.gov (United States)

    Boyle, A G; Rankin, S C; Duffee, L A; Morris, D

    2017-09-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is recognized as a cause of nosocomial infections in both human and veterinary medicine. Studies that examine the nasopharynx and guttural pouches of the horse as carriage sites for MRSA have not been reported. MRSA colonizes the nasopharynx and guttural pouch of horses. To determine the prevalence of MRSA in equine nasopharyngeal wash (NPW) and guttural pouch lavage (GPL) samples in a field population of horses. One hundred seventy-eight samples (123 NPW and 55 GPL) from 108 horses. Prospective study. Samples were collected from a convenience population of clinically ill horses with suspected Streptococcus equi subsp. equi (S. equi) infection, horses convalescing from a known S. equi infection, and asymptomatic horses undergoing S. equi screening. Samples were submitted for S. aureus aerobic bacterial culture with mannitol salt broth and two selective agars (cefoxitin CHROMagar as the PBP2a inducer and mannitol salt agar with oxacillin). Biochemical identification of Staphylococcus species and pulsed-field gel electrophoresis (PFGE), to determine clonal relationships between isolates, were performed. Methicillin-resistant Staphylococcus (MRS) was isolated from the nasopharynx of 7/108 (4%) horses. Three horses had MRSA (2.7%), and 4 had MR-Staphylococcus pseudintermedius (MRSP). MRSA was isolated from horses on the same farm. PFGE revealed the 3 MRSA as USA 500 strains. Sampling the nasopharynx and guttural pouch of community-based horses revealed a similarly low prevalence rate of MRSA as other studies sampling the nares of community-based horses. More study is required to determine the need for sampling multiple anatomic sites when screening horses for MRSA. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  14. Genomic Analysis of Third Generation Cephalosporin Resistant Escherichia coli from Dairy Cow Manure.

    Science.gov (United States)

    Rehman, Muhammad Attiq; Yin, Xianhua; Lepp, Dion; Laing, Chad; Ziebell, Kim; Talbot, Guylaine; Topp, Edward; Diarra, Moussa Sory

    2017-11-17

    The production of extended-spectrum β-lactamases (ESBLs) conferring resistance to new derivatives of β-lactams is a major public health threat if present in pathogenic Gram-negative bacteria. The objective of this study was to characterize ceftiofur (TIO)- or cefotaxime (FOX)-resistant Escherichia coli isolated from dairy cow manure. Twenty-four manure samples were collected from four farms and incubated under anaerobic conditions for 20 weeks at 4 °C or at 25 °C. A total of 37 TIO- or FOX-resistant E. coli were isolated from two of the four farms to determine their susceptibility to 14 antibiotics. Among the 37 resistant E. coli , 10 different serotypes were identified, with O8:H1 being the predominant serotype ( n = 17). Five isolates belonged to each of serotypes O9:NM and O153:H42, respectively. All 37 cephalosporin resistant isolates were multi-resistant with the most prevalent resistance spectrum being amoxicillin-clavulanic acid-ampicillin-cefoxitin-ceftiofur-ceftriaxone-chloramphenicol-streptomycin-sulfisoxazole-tetracycline-trimethoprim-sulfamethoxazole. The genomes of 18 selected isolates were then sequenced and compared to 14 selected human pathogenic E. coli reference genomes obtained from public repositories using different bioinformatics approaches. As expected, all 18 sequenced isolates carried at least one β-lactamase bla gene: TEM-1 , TEM-81 , CTX-M115 , CTX-M15 , OXA-1, or CMY-2 . Several other antibiotic resistance genes (ARGs) and virulence determinants were detected in the sequenced isolates and all of them harbored antimicrobial resistance plasmids belonging to classic Inc groups. Our results confirm the presence of diverse ESBL producing E. coli isolates in dairy cow manure stored for a short period of time. Such manure might constitute a reservoir of resistance and virulence genes for other bacteria that share the same environment.

  15. Evaluation of meat, fruit and vegetables from retail stores in five United Kingdom regions as sources of extended-spectrum beta-lactamase (ESBL)-producing and carbapenem-resistant Escherichia coli.

    Science.gov (United States)

    Randall, L P; Lodge, M P; Elviss, N C; Lemma, F L; Hopkins, K L; Teale, C J; Woodford, N

    2017-01-16

    We determined the prevalence and types of extended-spectrum β-lactamase (ESBL)-producing and carbapenem-resistant Escherichia coli in raw retail beef, chicken, pork, fruit and vegetables in five UK regions in 2013-14. Raw meat (n=397), and fruit and vegetable samples (n=400) were purchased from retail stores in London, East Anglia, North West England, Scotland and Wales. Samples were tested for the presence of ESBL-producing E. coli by plating enriched samples on CHROMagar CTX and CHROMagar ESBL, for AmpC-type E. coli by plating on "CHROMagar FOX" (CHROMagar ECC+16mg/L cefoxitin), and for carbapenem-resistant E. coli by plating on CHROMagar KPC. Additionally, pre-enrichment counts were performed on the above agars, and on CHROMagar ECC. Isolates of interest were characterised by MALDI-ToF to confirm identification, by PCR for bla CIT, bla CTX-M, bla OXA , bla SHV and bla TEM genes; ESBL or bla CIT genes were sequenced. Only 1.9% and 2.5% of beef and pork samples, respectively were positive for ESBL-producing E. coli after enrichment compared with 65.4% of chicken samples. 85.6% positive samples from chicken meat carried bla CTX-M-1 ; bla CTX-M-15 was not detected. None of the fruits or vegetables yielded ESBL-producing E. coli and none of the meat, fruit or vegetable samples yielded carbapenem-resistant E. coli. Retail chicken was more frequently a source of ESBL-producing E. coli than were beef, pork, fruit or vegetables. None of the foodstuffs yielded E. coli with CTX-M-15 ESBL, which dominates in human clinical isolates in the UK, and none yielded carbapenem-resistant E. coli. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

  16. Chronological Change of Resistance to β-Lactams in Salmonella enterica serovar Infantis Isolated from Broilers in Japan

    Directory of Open Access Journals (Sweden)

    Takehisa eChuma

    2013-05-01

    Full Text Available Epidemiologic surveillance study was conducted in southern Japan to determine the antimicrobial resistance phenotypes and characterize the β-lactamase genes and the plasmids harboring these genes in Salmonella enterica serovar Infantis (S. Infantis isolates from broilers. Between January, 2007 and December, 2008, a total of 1,472 fecal samples were collected and examined at the Laboratory of Veterinary Public Health, Kagoshima University, Japan. In 93 (6.3% isolates recovered, 33 (35.5% isolates showed resistance to cefotaxime, an extended-spectrum cephalosporin (ESC, conferred by TEM-20, TEM-52 and CTX-M-25 extended-spectrum β-lactamases (ESBLs. In addition to ESC-resistance, eight (8.6% isolates exhibited resistance to cefoxitin mediated by CMY-2 AmpC β-lactamase. Plasmid analysis and polymerase chain reaction replicon typing revealed the blaTEM-20 and blaCMY-2 genes were associated with IncP plasmids, blaTEM-52 was linked with a non-typable plasmid and blaCTX-M-25 was carried by an IncA/C plasmid. Non- β-lactam resistance to streptomycin, sulfamethoxazole and oxytetracycline encoded by the aadA1, sul1 and tet(A genes, respectively, was found in 86 (92.5% isolates. Resistance to kanamycin and ofloxacin was exhibited in 12 (12.9% and 11 (11.8% isolates, respectively, the former was mediated by aphA1-Iab. These data indicate that S. Infantis isolates producing ESBLs and AmpC β-lactamase have spread among broiler farms in Japan. These data demonstrated that the incidence of ESC-resistant S. Infantis carrying blaTEM-52 remarkably increased and S. Infantis strains harboring blaCMY-2, blaTEM-20 or blaCTX-M-25 genes emerged from broilers in Japan for the first time in 2007 and 2008.

  17. Oxacillin-susceptible methicillin-resistant Staphylococcus aureus (OS-MRSA), a hidden resistant mechanism among clinically significant isolates in the Wessex region/UK.

    Science.gov (United States)

    Saeed, K; Ahmad, N; Dryden, M; Cortes, N; Marsh, P; Sitjar, A; Wyllie, S; Bourne, S; Hemming, J; Jeppesen, C; Green, S

    2014-10-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is defined as S. aureus genetically having the mecA or mecC genes or phenotypically showing minimum inhibitory concentration (MIC) of oxacillin higher than 2 mg/L. However, recently, cefoxitin/oxacillin-susceptible mecA-positive S. aureus (OS-MRSA) has been reported worldwide. Little is known about the prevalence and virulence of these strains among clinically significant isolates in the UK. The aims were to (1) investigate the prevalence of OS-MRSA in seven major hospitals in the Wessex region/UK from a cohort of 500 clinically significant phenotypically identified MSSA isolates, (2) genetically characterise OS-MRSA strains by pulsed-field gel electrophoresis (PFGE) and compare these to common UK epidemic strains; and (3) to determine Panton-Valentine leukocidin (PVL; lukFS) gene carriage rates among these isolates. OS-MRSA was found in six isolates (1.2 %) of phenotypically identified and reported MSSA isolates by conventional methods. PFGE showed OS-MRSA strains to be genetically diverse and distinct from the common UK epidemic strains EMRSA-15 and EMRSA-16. None of these OS-MRSA stains carried the genes encoding PVL; however, overall positivity rate for PVL was 4.4 %, much higher than the nationally reported rates of 2 % in the UK. There are still many unknowns regarding phenotypic and/or genetic characterization of the emerging OS-MRSA isolates in the UK and worldwide. Data regarding their epidemiology and optimal therapy for infection are limited and need further investigation not only in the UK, but also worldwide, as it is likely to have an impact on the empirical treatment of S. aureus infections.

  18. Identification of novel microbes associated with pelvic inflammatory disease and infertility.

    Science.gov (United States)

    Haggerty, Catherine L; Totten, Patricia A; Tang, Gong; Astete, Sabina G; Ferris, Michael J; Norori, Johana; Bass, Debra C; Martin, David H; Taylor, Brandie D; Ness, Roberta B

    2016-09-01

    As pelvic inflammatory disease (PID) aetiology is not completely understood, we examined the relationship between select novel bacteria, PID and long-term sequelae. Fastidious bacterial vaginosis (BV)-associated bacteria (Sneathia (Leptotrichia) sanguinegens, Sneathia amnionii, Atopobium vaginae and BV-associated bacteria 1 (BVAB1)), as well as Ureaplasma urealyticum and Ureaplasma parvum were identified in cervical and endometrial specimens using organism-specific PCR assays among 545 women enrolled in the PID Evaluation and Clinical Health study. Risk ratios and 95% CIs were constructed to determine associations between bacteria, histologically confirmed endometritis, recurrent PID and infertility, adjusting for age, race, gonorrhoea and chlamydia. Infertility models were additionally adjusted for baseline infertility. Persistent detection of BV-associated bacteria was common (range 58% for A. vaginae to 82% for BVAB1) and elevated the risk for persistent endometritis (RRadj 8.5, 95% CI 1.6 to 44.6) 30 days post-cefoxitin/doxycycline treatment, independent of gonorrhoea and chlamydia. In models adjusted for gonorrhoea and chlamydia, endometrial BV-associated bacteria were associated with recurrent PID (RRadj 4.7, 95% CI 1.7 to 12.8), and women who tested positive in the cervix and/or endometrium were more likely to develop infertility (RRadj 3.4, 95% CI 1.1 to 10.4). Associations between ureaplasmas and PID sequelae were modest. To our knowledge, this is the first prospective study to demonstrate that S. sanguinegens, S. amnionii, BVAB1 and A. vaginae are associated with PID, failure of the Centers for Disease Control and Prevention-recommended treatment to eliminate short-term endometritis, recurrent PID and infertility. Optimal antibiotic regimens for PID may require coverage of novel BV-associated microbes. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  19. Extended-Spectrum β-lactam Resistance in the Enteric Flora of Patients at a Tertiary Care Medical Centre.

    Science.gov (United States)

    Landers, T F; Mollenkopf, D F; Faubel, R L; Dent, A; Pancholi, P; Daniels, J B; Wittum, T E

    2017-03-01

    The dissemination of Enterobacteriaceae expressing resistance to extended-spectrum cephalosporins, which are therapeutically used in both human and veterinary medicine, is of critical concern. The normal commensal flora of food animals may serve as an important reservoir for the zoonotic food-borne transmission of Enterobacteriaceae harbouring β-lactam resistance. We hypothesized that the predominant AmpC and ESBL genes reported in US livestock and fresh retail meat products, bla CMY -2 and bla CTX -M , would also be predominant in human enteric flora. We recovered enteric flora from a convenience sample of patients included in a large tertiary medical centre's Clostridium difficile surveillance programme to screen for and estimate the frequency of carriage of AmpC and ESBL resistance genes. In- and outpatient diarrhoeic submissions (n = 692) received for C. difficile testing at the medical centre's clinical diagnostic laboratory from July to December, 2013, were included. Aliquoted to a transport swab, each submission was inoculated to MacConkey broth with cefotaxime, incubated at 37°C and then inoculated to MacConkey agars supplemented with cefoxitin and cefepime to select for the AmpC and ESBL phenotypes, with bla CMY and bla CTX -M genotypes confirmed by PCR and sequencing. From the 692 diarrhoeic submissions, our selective culture yielded 184 isolates (26.6%) with reduced susceptibility to cefotaxime. Of these, 46 (6.7%) samples harboured commensal isolates carrying the AmpC bla CMY . Another 21 (3.0%) samples produced isolates harbouring the ESBL bla CTX -M : 19 carrying CTX-M-15 and 2 with CTX-M-27. Our results indicate that β-lactam resistance genes likely acquired through zoonotic food-borne transmission are present in the enteric flora of this hospital-associated population at lower levels than reported in livestock and fresh food products. © 2016 Blackwell Verlag GmbH.

  20. 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.

  1. Enterobacteriaceae Harboring AmpC (blaCMY) and ESBL (blaCTX-M) in Migratory and Nonmigratory Wild Songbird Populations on Ohio Dairies.

    Science.gov (United States)

    Mathys, Dimitria A; Mathys, Blake A; Mollenkopf, Dixie F; Daniels, Joshua B; Wittum, Thomas E

    2017-04-01

    Extended-spectrum β-lactamases (ESBLs) confer bacterial resistance to critically important antimicrobials, including extended-spectrum cephalosporins (ESCs). Livestock are important reservoirs for the zoonotic food-borne transmission of ESC-resistant enteric bacteria. Our aim is to describe the potential role of migratory and resident wild birds in the epidemiology of ESBL-mediated bacterial resistance on dairy farms. Using mist nets, we sampled wild migratory and resident birds either immediately adjacent to or 600 ft away from free-stall barns on three Ohio dairy farms during the 2014 and 2015 spring migrations. Individual swabs were used to obtain both a cloacal and external surface swab from each bird. Samples were inoculated into MacConkey broth containing cefotaxime then inoculated onto MacConkey agar with cefoxitin, cefepime, or meropenem to identify the bla CMY, bla CTX-M, and carbapenemase phenotypes, respectively. Six hundred twenty-three birds were sampled, 19 (3.0%) of which harbored bacteria with bla CMY and 32 (5.1%) harbored bacteria with bla CTX-M from either their cloacal sample or from their external swab. There was no difference in the prevalence of either gene between migratory and resident birds. Prevalence of bla CMY and bla CTX-M was higher among birds sampled immediately outside the barns compared with those sampled 600 ft away. Our results suggest that wild birds can serve as mechanical and/or biological vectors for Enterobacteriaceae with resistance to ESCs. Birds live in close contact with dairy cows and their feed, therefore, transmission locally between farms is possible. Finding a similar prevalence in migratory and nonmigratory birds suggests the potential for regional and intercontinental movement of these resistance genes via birds.

  2. Phenotypic Resistance to Disinfectants and Antibiotics in Methicillin-Resistant Staphylococcus aureus Strains Isolated from Pigs.

    Science.gov (United States)

    Espigares, E; Moreno Roldan, E; Espigares, M; Abreu, R; Castro, B; Dib, A L; Arias, Á

    2017-06-01

    The aim of this research was to study the phenotypic resistances to disinfectants and antibiotics in strains of methicillin-resistant Staphylococcus aureus (MRSA) obtained from Canary black pigs. Analyses were performed on 54 strains of MRSA, isolated in Canary black pigs from the province of Tenerife (Spain); all of them carried the mecA gene. The strains were isolated by means of nasal swab samples of healthy pigs, collected under veterinarian supervision. Bactericidal activity of antiseptics and disinfectants was tested by means of the dilution-neutralization method. Susceptibility to the disinfectants glutaraldehyde, peracetic acid and silver nitrate was assessed, as well as to the antiseptics chlorhexidine, benzalkonium chloride and povidone iodine. Susceptibility to a wide array of antibiotics representing the main groups was determined by means of the disc diffusion method. All the strains demonstrated susceptibility to the disinfectants tested at the recommended concentration, and even to dilutions equal to or lesser than 1/16. The most effective antiseptic and disinfectant were, respectively, chlorhexidine and silver nitrate. With regard to the antibiotics, the strains proved to be multiresistant. All presented phenotypic resistance to the β-lactam antibiotics ampicillin, penicillin and cefoxitin, as well as to numerous aminoglycosides, tetracycline and trimethoprim-sulfamethoxazole. It was also observed that 61.1% of the strains were carriers of plasmids. Our results underline that in the strains such as MRSA, which show multiple resistances to antibiotics, the antiseptics and disinfectants show great efficacy. Moreover, as other authors also suggest, for the treatment and prevention of infections caused by MRSA, the use of β-lactam and aminoglycoside antibiotics may be less effective. © 2016 Blackwell Verlag GmbH.

  3. Detecting bacteria and Determining Their Susceptibility to Antibiotics by Stochastic Confinement in Nanoliter Droplets using Plug-Based Microfluidics

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    Boedicker, J.; Li, L; Kline, T; Ismagilov, R

    2008-01-01

    This article describes plug-based microfluidic technology that enables rapid detection and drug susceptibility screening of bacteria in samples, including complex biological matrices, without pre-incubation. Unlike conventional bacterial culture and detection methods, which rely on incubation of a sample to increase the concentration of bacteria to detectable levels, this method confines individual bacteria into droplets nanoliters in volume. When single cells are confined into plugs of small volume such that the loading is less than one bacterium per plug, the detection time is proportional to plug volume. Confinement increases cell density and allows released molecules to accumulate around the cell, eliminating the pre-incubation step and reducing the time required to detect the bacteria. We refer to this approach as stochastic confinement. Using the microfluidic hybrid method, this technology was used to determine the antibiogram - or chart of antibiotic sensitivity - of methicillin-resistant Staphylococcus aureus (MRSA) to many antibiotics in a single experiment and to measure the minimal inhibitory concentration (MIC) of the drug cefoxitin (CFX) against this strain. In addition, this technology was used to distinguish between sensitive and resistant strains of S. aureus in samples of human blood plasma. High-throughput microfluidic techniques combined with single-cell measurements also enable multiple tests to be performed simultaneously on a single sample containing bacteria. This technology may provide a method of rapid and effective patient-specific treatment of bacterial infections and could be extended to a variety of applications that require multiple functional tests of bacterial samples on reduced timescales.

  4. Occurrence and antimicrobial susceptibility of Salmonella isolates recovered from the pig slaughter process in Romania.

    Science.gov (United States)

    Morar, Adriana; Sala, Claudia; Imre, Kálmán

    2015-01-15

    Reported human salmonellosis cases have increased in Romania. Antibiotic susceptibility testing of Salmonella strains isolated from pork and chicken meat indicate a worrying multidrug resistance pattern. This study aimed to investigate the occurrence of Salmonella and to evaluate the antibiotic resistance of Salmonella strains in a pig slaughterhouse-processing complex, which receives animals from 30% of the large industrialized swine farms in Romania. A total of 108 samples, including pork (n = 47), packaged pork products (n = 44), scald water sludge (n = 8), and detritus from the hair removal machine of the slaughterhouse (n = 9) were examined for the presence of Salmonella through standard methods. The antibiotic susceptibility of the isolated strains to 17 antibiotics was tested using the Vitek 2 system. Twenty-six (24.1%) samples were found to be Salmonella positive; this included 25.5% of meat samples and 15.9% of packaged products, as well as samples from two different points of the slaughter (41.2%). Resistance was observed against tetracycline (61.5%), ampicillin (50%), piperacillin (50%), trimethoprim-sulfamethoxazole (34.6%), amoxicillin/clavulanic acid (26.9%), nitrofurantion (23.1%), cefazolin (15.4%), piperacillin/tazobactam (7.7%), imipenem (3.8%), ciprofloxacin (3.8%), and norfloxacin (3.8%). No resistance towards cefoxitin, cefotaxime, ceftazidime, cefepime, amikacin, and gentamicin was found. Our study demonstrated the occurrence of multidrug-resistant Salmonella strains in the investigated pork production complex and highlighted it as a potential source of human infections. The results demonstrate the seriousness of antibiotic resistance of Salmonella in Romania, while providing a useful insight for the treatment of human salmonellosis by specialists.

  5. Multiple Food-Animal-Borne Route in Transmission of Antibiotic-Resistant Salmonella Newport to Humans

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    Hang Pan

    2018-01-01

    Full Text Available Characterization of transmission routes of Salmonella among various food-animal reservoirs and their antibiogram is crucial for appropriate intervention and medical treatment. Here, we analyzed 3728 Salmonella enterica serovar Newport (S. Newport isolates collected from various food-animals, retail meats and humans in the United States between 1996 and 2015, based on their minimum inhibitory concentration (MIC toward 27 antibiotics. Random Forest and Hierarchical Clustering statistic was used to group the isolates according to their MICs. Classification and Regression Tree (CART analysis was used to identify the appropriate antibiotic and its cut-off value between human- and animal-population. Two distinct populations were revealed based on the MICs of individual strain by both methods, with the animal population having significantly higher MICs which correlates to antibiotic-resistance (AR phenotype. Only ∼9.7% (267/2763 human isolates could be attributed to food–animal origins. Furthermore, the isolates of animal origin had less diverse antibiogram than human isolates (P < 0.001, suggesting multiple sources involved in human infections. CART identified trimethoprim-sulfamethoxazole to be the best classifier for differentiating the animal and human isolates. Additionally, two typical AR patterns, MDR-Amp and Tet-SDR dominant in bovine- or turkey-population, were identified, indicating that distinct food-animal sources could be involved in human infections. The AR analysis suggested fluoroquinolones (i.e., ciprofloxacin, but not extended-spectrum cephalosporins (i.e., ceftriaxone, cefoxitin, is the adaptive choice for empirical therapy. Antibiotic-resistant S. Newport from humans has multiple origins, with distinct food-animal-borne route contributing to a significant proportion of heterogeneous isolates.

  6. An unusual antibiotic susceptibility pattern in a Mycobacterium Cosmeticum strain isolated from the chesapeake bay

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    Vajini Atukorale

    2017-01-01

    Full Text Available Objective/Background: Mycobacterium cosmeticum, first described in 2004, was recovered from a patient undergoing a cosmetic procedure. Subsequently, this species was associated with an outbreak in a nail salon. In all cases, the isolates were susceptible to all antibiotics tested. Recently, however, we recovered a strain of M. cosmeticum from the Chesapeake Bay, resistant to 11 of 14 antimicrobials. The objective of this work was to present our findings on the resistance and susceptibility of this isolate to various antibiotics. Materials and Methods: Surface water samples were collected from 10 sites in the Chesapeake Bay and upper tributaries to assess microbial diversity and antibiotic resistance. Site selection was based on proximity to agricultural runoff, industrial contaminants, and sewage effluents. Samples were processed and recovered organisms were identified and subjected to antimicrobial-susceptibility testing. Results: One nontuberculous species, identified as M. cosmeticum, was recovered from Sandy Point State Park. Resistance was detected to several antibiotics: doxycycline (16 μg/mL, tigecycline (≥4 μg/mL, clarithromycin (8 μg/mL, trimethoprim/sulfamethoxazole (≥8/152 μg/mL, imipenem (32 μg/mL, cefoxitin (32 μg/mL, ethionamide (≥20 μg/mL, and streptomycin (16 μg/mL. Of the 14 antibiotics tested, only the fluoroquinolones, linezolid, and amikacin demonstrated potent activity with susceptible minimum inhibitory concentrations. Conclusion: The antimicrobial resistance identified in this M. cosmeticum isolates from the Chesapeake Bay raises some important concerns: (a why is the susceptibility pattern in this isolate so different from the previously published reports, (b how did resistance emerge in this isolate, (c is there a source of environmental exposure to antibiotics, (d is it a human isolate transferred to the watershed, or (e is it the result of lateral gene transfer with other resistant organisms in the Bay?

  7. Vibrio vulnificus outbreaks in Dutch eel farms since 1996: strain diversity and impact.

    Science.gov (United States)

    Haenen, O L M; van Zanten, E; Jansen, R; Roozenburg, I; Engelsma, M Y; Dijkstra, A; Boers, S A; Voorbergen-Laarman, M; Möller, A V M

    2014-04-03

    Vibrio vulnificus is a potentially zoonotic bacterial pathogen of fish, which can infect humans (causing necrotic fasciitis). We analysed 24 V. vulnificus isolates (from 23 severe eel disease outbreaks in 8 Dutch eel farms during 1996 to 2009, and 1 clinical strain from an eel farmer) for genetic correlation and zoonotic potential. Strains were typed using biotyping and molecular typing by high-throughput multilocus sequence typing (hiMLST) and REP-PCR (Diversilab®). We identified 19 strains of biotype 1 and 5 of biotype 2 (4 from eels, 1 from the eel farmer), that were subdivided into 8 MLST types (ST) according to the international standard method. This is the first report of V. vulnificus biotype 1 outbreaks in Dutch eel farms. Seven of the 8 STs, of unknown zoonotic potential, were newly identified and were deposited in the MLST database. The REP-PCR and the MLST were highly concordant, indicating that the REP-PCR is a useful alternative for MLST. The strains isolated from the farmer and his eels were ST 112, a known potential zoonotic strain. Antimicrobial resistance to cefoxitin was found in most of the V. vulnificus strains, and an increasing resistance to quinolones, trimethoprim + sulphonamide and tetracycline was found over time in strain ST 140. Virulence testing of isolates from diseased eels is recommended, and medical practitioners should be informed about the potential risk of zoonotic infections by V. vulnificus from eels for the prevention of infection especially among high-risk individuals. Additional use of molecular typing methods such as hiMLST and Diversilab® is recommended for epidemiological purposes during V. vulnificus outbreaks.

  8. Profiling of antibiotic resistance of bacterial species recovered from routine clinical isolates in Ethiopia.

    Science.gov (United States)

    Ten Hove, Robert-Jan; Tesfaye, Melaku; Ten Hove, Witold Frederik; Nigussie, Mesfin

    2017-06-26

    With the alarming rise in antibiotic resistance in African countries, the need for a surveillance system in the region has become pressing. The rapid expansion of data networks makes it possible to set up healthcare applications that can be both cost-efficient and effective. Large data sets are available for assessment of current antibiotic resistance among Ethiopian patients. Based on the data-presentation, a practical approach is proposed on how diagnostic laboratories can participate remedial action against antibiotic resistance in Ethiopia. In Addis Ababa (Ethiopia), raw data comprising bacterial species name, specimen type and antibiograms covering the period January 2014 to May 2015 was accessed from the laboratory information management system. Using R code, the data was read and fitted into data-frames and analyzed to assess antibiotic resistance in the Ethiopian patient population. Susceptibility to an antibiotic was tested with 14.983 cultures of 54 different bacterial species or subgroups, isolated from 16 types of specimen. Half of the cultures (n = 6444) showed resistance to an antibiotic. Resistance against penicillin was highest with, on average, 91.1% of 79 bacterial cultures showing resistance. Very high resistance rates were also observed for ampicillin, whereas resistance was lowest with cefoxitin. Extraction and analysis of raw-data from the laboratory database is relatively simple and can provide valuable insight into the relationships between type of sample and drug-resistance in countries where such data is still scarce. With the largest number of antibiotic resistance tests described for Ethiopia, a tool is proposed for consistent data collection with specified core variables. Trends in antibiotic resistance can be revealed and treatment failures avoided when used as an easy accessible reference application for healthcare providers.

  9. Bacterial Species and Antibiotic Sensitivity in Korean Patients Diagnosed with Acute Otitis Media and Otitis Media with Effusion.

    Science.gov (United States)

    Kim, Sang Hoon; Jeon, Eun Ju; Hong, Seok Min; Bae, Chang Hoon; Lee, Ho Yun; Park, Moo Kyun; Byun, Jae Yong; Kim, Myung Gu; Yeo, Seung Geun

    2017-04-01

    Changes over time in pathogens and their antibiotic sensitivity resulting from the recent overuse and misuse of antibiotics in otitis media (OM) have complicated treatment. This study evaluated changes over 5 years in principal pathogens and their antibiotic sensitivity in patients in Korea diagnosed with acute OM (AOM) and OM with effusion (OME). The study population consisted of 683 patients who visited the outpatient department of otorhinolaryngology in 7 tertiary hospitals in Korea between January 2010 and May 2015 and were diagnosed with acute AOM or OME. Aural discharge or middle ear fluid were collected from patients in the operating room or outpatient department and subjected to tests of bacterial identification and antibiotic sensitivity. The overall bacteria detection rate of AOM was 62.3% and OME was 40.9%. The most frequently isolated Gram-positive bacterial species was coagulase negative Staphylococcus aureus (CNS) followed by methicillin-susceptible S. aureus (MSSA), methicillin-resistant S. aureus (MRSA), and Streptococcus pneumonia (SP), whereas the most frequently isolated Gram-negative bacterium was Pseudomonas aeruginosa (PA). Regardless of OM subtype, ≥ 80% of CNS and MRSA strains were resistant to penicillin (PC) and tetracycline (TC); isolated MRSA strains showed low sensitivity to other antibiotics, with 100% resistant to PC, TC, cefoxitin (CFT), and erythromycin (EM); and isolated PA showed low sensitivity to quinolone antibiotics, including ciprofloxacin (CIP) and levofloxacin (LFX), and to aminoglycosides. Bacterial species and antibiotic sensitivity did not change significantly over 5 years. The rate of detection of MRSA was higher in OME than in previous studies. As bacterial predominance and antibiotic sensitivity could change over time, continuous and periodic surveillance is necessary in guiding appropriate antibacterial therapy. © 2017 The Korean Academy of Medical Sciences.

  10. First detection of methicillin-resistant Staphylococcus aureus ST398 and Staphylococcus pseudintermedius ST68 from hospitalized equines in Spain.

    Science.gov (United States)

    Gómez-Sanz, E; Simón, C; Ortega, C; Gómez, P; Lozano, C; Zarazaga, M; Torres, C

    2014-05-01

    Eight coagulase-positive staphylococci from equines with different pathologies obtained between 2005 and 2011 were investigated. Isolates were characterized by different molecular techniques (spa-, agr-, MLST), and clonal relatedness of strains was investigated by ApaI and SmaI PFGE. Anti-microbial resistance and virulence profiles were determined. Six isolates were identified as Staphylococcus aureus, and two as Staphylococcus pseudintermedius. Of these, four isolates were methicillin-resistant S. aureus (MRSA) ST398 and one S. pseudintermedius was mecA positive and typed as ST68. One MRSA ST398 strain was isolated in 2005 and might be one of the earliest MRSA ST398 descriptions in Spain. All 5 mecA-positive strains were multidrug resistant and were isolated from hospitalized equines. Three MRSA ST398 strains carried the recently described transposon Tn559 within the chromosomal radC gene. The mecA-positive S. pseudintermedius ST68 strain was also multidrug resistant and harboured the erm(B)-Tn5405-like element. This ST68 strain presented a clear susceptible phenotype to oxacillin and cefoxitin regardless of the presence of an integral and conserved mecA gene and mecA promoter, which enhances the need for testing the presence of this gene in routine analysis to avoid treatment failures. These data reflect the extended anti-microbial resistance gene acquisition capacities of both bacterial species and evidence their pathogenic properties. The first detection of MRSA ST398 and S. pseudintermedius ST68 in horses in Spain is reported. © 2013 Blackwell Verlag GmbH.

  11. Detection of Macrolide, Lincosamide and Streptogramin Resistance among Methicillin Resistant Staphylococcus aureus (MRSA in Mumbai

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    Arunagiri Subramanian

    2015-01-01

    Full Text Available Background: The increase in incidence of Methicillin Resistant Staphyloccocus aureus (MRSA and its extraordinary potential to develop antimicrobial resistance has highlighted the need for better agents to treat such infections. This has led to a renewed interest in use of new drugs for treatment with clindamycin and quinuprsitin-dalfopristin being the preferred choice for treatment. Aim & Objectives: This study was undertaken to detect the prevalence of MacrolideLincosamide-Streptogramin (MLS resistance among clinical isolates of MRSA.Material and Methods:Two hundred and thirty clinical isolates of S. aureus were subjected to routine antibiotic susceptibility testing including cefoxitin, erythromycin and quinupristindalfopristin. Inducible resistance to clindamycin was tested by 'D' test as per Clinical and Laboratory Standards Institute (CLSI guidelines. Results: Out of all S. aureus isolates, 93.91% were identified as MRSA. In the disc diffusion testing, 81.5% of isolates showed erythromycin resistance. Among these, the prevalence of constitutive (cMLS , inducible (iMLS b b and MS-phenotype were 35.80%, 31.82% and 32.39% respectively by the D-test method. 77.8% of isolates were resistant to quinupristin-dalfopristin and the Minimum Inhibitory Concentration (MIC ranged from 4–32 µg/ml. 89.20% of isolates were resistant to both quinupristin-dalfopristin and erythromycin of which 35.03%, 35.67% and 29.30% belonged to iMLS , cMLS and MS phenotype respectively. Conclusion: The emergence of quinupristindalfopristin resistance and MLS phenotypes brings b about the need for the simple and reliable D-test in routine diagnosis and further susceptibility testing for proper antimicrobial therapy.

  12. Cefmetazole for bacteremia caused by ESBL-producing enterobacteriaceae comparing with carbapenems.

    Science.gov (United States)

    Fukuchi, Takahiko; Iwata, Kentaro; Kobayashi, Saori; Nakamura, Tatsuya; Ohji, Goh

    2016-08-18

    ESBL (Extended spectrum beta-lactamase) producing enterobacteriaceae are challenging organisms with little treatment options. Carbapenems are frequently used, but the emergence of carbapenem resistant enterobacteriaceae is a concerning issue, which may hinder the use of carbapenems. Although cephamycins such as cefoxitin, cefmetazole or cefotetan are effective against ESBL-producers in vitro, there are few clinical data demonstrating effects against bacteremia caused by these organisms. We performed a retrospective observational study on cases of bacteremia caused by ESBL-producers to investigate the efficacy of cefmetazole compared with carbapenems. We also evaluated whether the trend of antibiotic choice changed over years. Sixty-nine patients (male 34, age 69.2 ± 14.4), including two relapse cases, were reviewed for this analysis. The most common causative organisms were Escherichia coli (64, 93 %), followed by Klebsiella pneumoniae and K. oxytoca (2 each, 4 %). The group that received carbapenem therapy (43, 62 %) had increased severity in the Pittsburgh Bacteremic score than the group that received cefmetazole therapy, (1.5 ± 1.5 vs 2.5 ± 2.1, p = 0.048), while analysis of other factors didn't reveal any statistical differences. Five patients in the carbapenem group and one patient in the cefmetazole group died during the observation period (p = 0.24). CTX-M-9 were predominant in this series (59 %). Infectious disease physicians initially recommended carbapenems at the beginning of the current research period, which gradually changed over time favoring the use of cefmetazole instead (p = 0.002). Cefmetazole may be safely given to patients with bacteremia caused by ESBL-producers as a definitive therapy, if one can select out relatively stable patients.

  13. Distribution and Antimicrobial Susceptibility of Foodborne Salmonella Serovars in Eight Provinces in China from 2007 to 2012 (Except 2009).

    Science.gov (United States)

    Wang, Yin; Cao, Chenyang; Alali, Walid Q; Cui, Shenghui; Li, Fengqin; Zhu, Jianghui; Wang, Xin; Meng, Jianghong; Yang, Baowei

    2017-07-01

    One thousand four hundred ninety-one Salmonella isolates recovered from retail foods including chicken, beef, fish, pork, dumplings, and cold dishes in China in 2007, 2008, 2010, 2011, and 2012 were analyzed for distribution of serotype and antimicrobial susceptibility. A total of 129 Salmonella serotypes were detected among 1491 isolates. Salmonella Enteritidis (21.5%), Typhimurium (11.0%), Indiana (10.8%), Thompson (5.4%), Derby (5.1%), Agona (3.8%), and Shubra (3.0%) were the seven most important serotypes in 1491 isolates. For antibiotic susceptibility, except 16 (1.1%) isolates were susceptible to all tested antibiotics, 131 (8.8%) resisted 1-2 and 1344 (90.1%) resisted three or more antibiotics. One thousand forty-six (70.2%) of 1491 Salmonella isolates were identified as multidrug-resistant (MDR) isolates, which could resist three or more categories of antibiotics. Resistance to sulfisoxazole (78.1%) was most common among the tested Salmonella, followed by tetracycline (70.6%), trimethoprim/sulfamethoxazole (68.0%), and nalidixic acid (63.4%). Resistances to amikacin (20.0%), levofloxacin (18.7%), gatifloxacin (17.9%), ceftriaxone (17.7%), and cefoxitin (13.2%) were less frequently detected. Resistance to fluoroquinolones was most common among Salmonella Shubra and Indiana isolates, while resistance to cephalosporins was frequently detected among Salmonella Thompson isolates. The results highlighted the diversity of Salmonella serotypes and the high prevalence of Salmonella MDR isolates in China. Compared with Salmonella Enteritidis and Typhimurium isolates, the higher fluoroquinolones and cephalosporins resistance rates of some individual serotypes (Salmonella Shubra, Indiana, and Thompson) also provided more information for further study related to fluoroquinolones or cephalosporin-resistant Salmonella.

  14. Antimicrobial resistance among pathogenic bacteria from mink (Neovison vison) in Denmark.

    Science.gov (United States)

    Nikolaisen, Nanett Kvist; Lassen, Desireé Corvera Kløve; Chriél, Mariann; Larsen, Gitte; Jensen, Vibeke Frøkjær; Pedersen, Karl

    2017-09-13

    For proper treatment of bacterial infections in mink, knowledge of the causative agents and their antimicrobial susceptibility patterns is crucial. The used antimicrobials are in general not registered for mink, i.e. most usage is "off-label". In this study, we report the patterns of antimicrobial resistance among pathogenic bacteria isolated from Danish mink during the period 2014-2016. The aim of this investigation was to provide data on antimicrobial resistance and consumption, to serve as background knowledge for new veterinary guidelines for prudent and optimal antimicrobial usage in mink. A total number of 308 Escherichia coli isolates, 41 Pseudomonas aeruginosa, 36 Streptococcus canis, 30 Streptococcus dysgalactiae, 55 Staphylococcus delphini, 9 Staphylococcus aureus, and 20 Staphylococcus schleiferi were included in this study. Among E. coli, resistance was observed more frequently among the hemolytic isolates than among the non-hemolytic ones. The highest frequency of resistance was found to ampicillin, 82.3% and 48.0% of the hemolytic of the non-hemolytic isolates, respectively. The majority of the P. aeruginosa isolates were only sensitive to ciprofloxacin and gentamicin. Among the Staphylococcus spp., the highest occurrence of resistance was found for tetracycline. Regarding the nine S. aureus, one isolate was resistant to cefoxitin indicating it was a methicillin-resistant Staphylococcus aureus. Both β-hemolytic Streptococcus species showed high levels of resistance to tetracycline and erythromycin. The antimicrobial consumption increased significantly during 2007-2012, and fluctuated at a high level during 2012-2016, except for a temporary drop in 2013-2014. The majority of the prescribed antimicrobials were aminopenicillins followed by tetracyclines and macrolides. The study showed that antimicrobial resistance was common in most pathogenic bacteria from mink, in particular hemolytic E. coli. There is a need of guidelines for prudent use of

  15. Molecular Identification and Conventional Susceptibility Testing of Iranian Clinical Mycobacterium fortuitum Isolates

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    Parvin Heidarieh

    2010-01-01

    Full Text Available Rapidly growing mycobacteria (RGM are capable of producing diseases in humans. Since mycobacteria vary in their susceptibility, precise identification is critical for adoption of correct drug therapy. The main aim of this study was molecular identification and evaluation of antimicrobial susceptibility pattern of Iranian clinically isolated Myocbacterium fortuitum.Materials and MethodsA total of 72 presumptively identified isolates of clinical atypical mycobacteria collected by Isfahan Research Center for Infectious Diseases & Tropical Medicine during 2006-2008 were included in the current study. A combination of conventional and molecular tests was applied to identify the isolates. Molecular methods including genus and group specific PCR and PCR-Restriction Algorithm (PRA based on hsp65 gene were applied to achieve exact identification of mycobacterial strains. Antimicrobial susceptibility testing on M. fortuitum isolates was performed by in-house prepared broth microdilution test..ResultsOut of 72 collected atypical mycobacteria isolates, we identified 25 strains of M. fortuitum. All strains had the specific molecular markers of mycobacterial identity and similar species specific PRA pattern of the international type strain of M. fortuitum. Drug susceptibility testing showed that the M. fortuitum isolates are sensitive to amikacin, sulfamethoxazole and ciprofloxacin (100%, imipenem (92%, clarithromycin (76%, cefoxitin (56% and doxycycline (16%.ConclusionMolecular identification of atypical mycobacteria based on PRA is a reliable and rapid approach which can identify mycobacterial strains to the species level. Our study showed that M. fortuitum plays a significant role in pulmonary and extrapulmonary infection in patients and should be given proper considerations when clinical samples are processed.

  16. Binding of TEM-1 beta-lactamase to beta-lactam antibiotics by frontal affinity chromatography.

    Science.gov (United States)

    Chen, Xiu; Li, Yuhua; Zhang, Yan; Yang, Jianting; Bian, Liujiao

    2017-04-15

    TEM-1 beta-lactamases can accurately catalyze the hydrolysis of the beta-lactam rings in beta-lactam antibiotics, which make beta-lactam antibiotics lose its activity, and the prerequisite for the hydrolysis procedure in the binding interaction of TEM-1 beta-lactamases with beta-lactam antibiotics is the beta-lactam rings in beta-lactam antibiotics. Therefore, the binding of TEM-1 beta-lactamase to three beta-lactam antibiotics including penicillin G, cefalexin as well as cefoxitin was explored here by frontal affinity chromatography in combination with fluorescence spectra, adsorption and thermodynamic data in the temperature range of 278-288K under simulated physiological conditions. The results showed that all the binding of TEM-1 beta-lactamase to the three antibiotics were spontaneously exothermic processes with the binding constants of 8.718×10 3 , 6.624×10 3 and 2.244×10 3 (mol/L), respectively at 288K. All the TEM-1 beta-lactamases were immobilized on the surface of the stationary phase in the mode of monolayer and there existed only one type of binding sites on them. Each TEM-1 beta-lactamase bound with only one beta-lactam antibiotic and hydrogen bond interaction and Van der Waals force were the main forces between them. This work provided an insight into the binding interactions between TEM-1 beta-lactamases and beta-lactam antibiotics, which may be beneficial for the designing and developing of new substrates resistant to TEM-1 beta-lactamases. Copyright © 2017 Elsevier B.V. All rights reserved.

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

    Science.gov (United States)

    Kulangara, Vinodkumar; Nair, Neetha; 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.

  18. Coagulase negative staphylococci - a fast emerging threat.

    Science.gov (United States)

    Latif, Mahwish; Usman, Javaid; Gilani, Mehreen; Munir, Tehmina; Mushtaq, Maria; Anjum, Rabia

    2015-03-01

    To determine the frequency of isolation of coagulase-negative staphylococci and their resistance to methicillin over a period of time. The descriptive cross-sectional study was carried out at Army Medical College, Rawalpindi, from June 2009 to May 2012, and comprised clinical samples mostly from patients admitted to the intensive care unit. They were inoculated onto appropriate culture media depending upon the specimen. After 24-hour incubation at 35°C, coagulase-negative staphylococci were identified on the basis of colony morphology, gram staining, a positive catalase and a negative tube coagulase test.Methicillin resistance among the isolated staphylococci was determined using a 30µg Cefoxitin disc as per the Clinical and Laboratory Standards Institute protocol. Number of coagulase-negative staphylococci for each year and their methicillin resistance rates were calculated. A comparison was made with methicillin resistant staphylococcus aureus) isolated during the same period. Of the total 1331 specimens studies over three years, 581(43.65%) were coagulase-negative staphylococci. The rate of coagulase-negative staphylococci and methicillin resistance was higher each year; 110(26.6%) in May 2009-Jun 2010, 134(36.5%) in 2011, and 337(61%) in 2012. Methicillin resistance rates also increased from 25(22.7%) to 46(34.3%) and then to 201(59.6%) in 2012.Maximum isolated specimens came from blood 311(53.5%), followed by pus/swabs 204(35.1%). The frequency of isolation of coagulase-negative staphylococci and its methicillin resistance among hospitalised patients is on the rise.

  19. The prevalence of inducible and constitutive clindamycin resistance among the nasal isolates of staphylococci.

    Science.gov (United States)

    Mahesh C, Baragundi; Ramakant B, Kulkarni; Jagadeesh V, Sataraddi

    2013-08-01

    One of the important sources of Staphylococci which causes nosocomial infections, is the nasal carriage of Staphylococci among Health Care Workers (HCWs). The commonest antibiotic which is preferred for the treatment of the methicillin and multi drug resistant Staphylococcal infections is clindamycin. The inducible clindamycin resistance in Staphylococci is not detected by the routine antibiotic susceptibility testing and it results in treatment failures. The present study was undertaken to know the prevalence of constitutive and inducible clindamycin resistance and its correlation with the methicillin resistance among the nasal isolates of Staphylococci which were obtained from different HCWs. Nasal swabs were collected from 206 HCWs and they were processed. The Staphylococci which were isolated were tested for methicillin resistance by using cefoxitin (30 μg) discs. The inducible clindamycin resistance was tested by using erythromycin (15 μg) and clindamycin (2μg) discs and the D test according to the CLSI guidelines. Inducible clindamycin resistance was seen in 21(16.40%) of the S.aureus and 14 (7.56%) of the coagulase negative Staphylococcal isolates. Constitutive clindamycin resistance was seen in 23(17.96%) of the S.aureus and 43(23.24%) of the coagulase negative Staphylococcal isolates. The inducible and constitutive clindamycin resistance was more common among the methicillin resistant Staphylococcal isolates. The prevalence of inducible and constitutive clindamycin resistance in the nasal Staphylococcal isolates which were obtained from the HCWs was high, especially among the methicillin resistant Staphylococci. The D test which is recommended by the CLSI should be routinely done to detect inducible clindamycin resistance, to prevent treatment failures.

  20. Molecular Characteristics of Nasal Carriage Methicillin-Resistant Coagulase Negative Staphylococci in School Students.

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    Iravani Mohammad Abadi, Mohammad; Moniri, Rezvan; Khorshidi, Ahmad; Piroozmand, Ahmad; Mousavi, Seyed Gholam Abbas; Dastehgoli, Kamran; Mirzaei Ghazikalayeh, Hamed

    2015-06-01

    Coagulase-negative staphylococci (CoNS) are opportunistic pathogens. Methicillin resistance is common in CoNS and may play an important role as reservoir of staphylococcal cassette chromosome mec (SCCmec) for Staphylococcus aureus. The aim of this study was to determine molecular characteristics of nasal carriage of methicillin-resistant coagulase negative staphylococci among students. MR-CoNS from both nares of students were collected. Resistance to methicillin was determined by cefoxitin (30μg) disk diffusion test. SCCmec typing was performed using multiplex PCR by mec complex classes and ccr genes. Antimicrobial susceptibility profiles were determined on Mueller-Hinton agar according to CLSI. A total of 600 consecutive students were enrolled in this study; 430 of whom (71.7%) had CoNS. Seventy-two MR-CoNS strains, 21 (29.2%) S. lugdunensis, 17 (23.6%) S. haemolyticus, 17 (23.6%) S. saprophyticus, 9 (12.5%) S. epidermidis and 8 (11.1%) S. schleiferi were isolated. MR-CoNS rate in nasal carriage was 16.7%. All strains were susceptible to vancomycin. Forty-eight (66.7%) had a single SCCmec type including types I (n = 5), II (n = 4), III (n = 7), IV (n = 19) and V (n = 13), whereas 5 (6.9%) had two types including III + IV (n = 2), III + V (n = 1) and IV + V (n = 2). Nineteen strains (26.4%) were non-typeable for their SCCmec and ccr. Types IV and V SCCmec were associated with S. lugdunensis and S. haemolyticus, respectively. SCCmec types IV and V were prevalent in MR-CoNS and few isolates could harbor more than one type.

  1. Isolation and Detection of Methicillin-Resistant Staphylococci in Healthy Broilers in Nsukka Southeast, Nigeria

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    Ifeoma Chinyere UGWU

    2015-03-01

    Full Text Available This study was conducted to isolate and detect methicillin-resistant staphylococci (MRS in healthy broilers in Nsukka Southeast, Nigeria and determine the antibiogram of the isolates. Cloacal and skin swabs were collected from each of 101 randomly sampled broilers meant for slaughter. The samples were processed for isolation and identification of methicillin-resistant Staphylococcus species, following standard methods. Confirmation of methicillin-resistance by the isolates was done using penicillin binding protein 2a (PBP2a kit. Phenotypic resistance of the isolates to antimicrobial agents was determined using disc diffusion method. Out of 202 samples processed, 200 (99.01% yielded positive growth of staphylococci on oxacillin-supplemented oxacillin-resistance staphylococcal agar base (ORSAB. A total of 200 methicillin-resistant staphylococcal isolates were obtained. Of these, 91 (45.5% were identified as methicillin-resistant coagulase-positive Staphylococcus (MRCoPS, while 109 (54.5% were identified as methicillin-resistant coagulase-negative Staphylococcus species (MRCoNS. Out of the 91 MRCoPS, 53 (58.2% were identified as methicillin-resistant Staphylococcus aureus (MRSA. Resistance of the isolates was 99.5% to erythromycin and chloramphenicol, 100% to oxacillin, 76.5% to gentamicin, 96.5% to clindamycin, 92.5% to ciprofloxacin, 99% to sulphamethoxazole/trimethoprim and tetracycline, and 98.5% to streptomycin and cefoxitin. All the isolates were multidrug resistant. This study has shown that healthy broilers reared and slaughtered in Nsukka Southeast, Nigeria harbour multidrug-resistant MRS and thus serve as their reservoirs.

  2. Susceptibility of clinical methicillin-resistant Staphylococci isolates to new antibiotics.

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    Oksuz, Lutfiye; Gurler, Nezahat

    2013-11-15

    The treatment of methicillin-resistant staphylococcal infections has been a growing problem both in and out of hospitals for the past 30 years. Therefore, there is a need for other antibiotics as an alternative to glycopeptides in the treatment of methicillin-resistant staphylococcal infections. This study investigated the in vitro susceptibility of 49 methicillin-resistant Staphylococcus aureus (MRSA) and 59 methicillin-resistant coagulase negative staphylococci (MRCNS) clinical isolates to daptomiycin, telithromycin, tigecyclin, quinupristin/dalfopristin, and linezolid. The identification of the strains was made by conventional methods. Antibiotic susceptibility tests were performed according to CLSI. Methicillin resistance was determined by cefoxitin disk. Susceptibilities of the strains to daptomycin, quinupristin/dalfopristin, tigecycline, and vancomycin were performed using the E-test according to the recommendations of CLSI 2011 and the manufacturer. Two strains of MRCNS were resistant, and one was teicoplanin intermediate. It was found that one (2%) strain of MRSA and two (3%) strains of MRCNS were resistant to tigecyclin. Telithromycin resistance was detected in 33% of MRSA strains and 37% of MRCNS strains. Inducible clindamycin resistance was found in nine (18.4%) strains of MRSA and eighteen (30.5%) strains of MRCNS. All strains were susceptible to daptomiycin, quinupristin/dalfopristin, and linezolid. Although it has recently been used, telithromycin has a high percentage of resistance; its use for methicillin-resistant staphylococcal strains, therefore, should be limited. Daptomycin and quinupristin/dalfopristin were found to be effective against MRSA and MRCNS strains and were concluded to be a good choice in the treatment of methicillin-resistant staphylococci.

  3. Staphylococcus aureus: resistance pattern and risk factors

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    Mohammad Naghavi-Behzad

    2015-03-01

    Full Text Available Introduction: Methicillin resistant Staphylococcus aureus (MRSA has emerged as a nosocomial pathogen of major worldwide importance and is an increasingly frequent cause of community-acquired infections. In this study, different risk factors and MRSA resistance pattern were investigated. Methods: In a 24 months period, all of the patients who were confined to bed in the surgery ward were included in the study. Then they were assessed to find out as if they had MRSA infection when hospitalized and once when they were discharged. Almost 48 h after admission, when patients were discharged, social and medical histories were acquired. Acquired samples were examined. Results: During the present study of 475 patients, 108 patients (22.8% had S. aureus. About frequency of antibiotic resistance among collected S. aureus colonies, erythromycin resistance, was the most frequent antibiotic resistance, also resistance to vancomycin was 0.4% that was the least. Only hospitalization duration had statistically significant correlation with antibiotic resistance, also resistance to erythromycin had statistically significant relation with history of surgery and alcohol consumption. Of all 34 MRSA species, 22 (64.7% samples were resistant to erythromycin, 17 (50.0% resistant to cefoxitin, 5 (14.7% resistant to mupirocin, 1 (2.9% resistant to vancomycin and 1 (2.9% resistant to linezolid. Conclusion: The results of the current study show that among hospitalized patients, there is resistance against methicillin. Since based on results of the study there is resistance against oxacillin and erythromycin in most cases, administering appropriate antibiotics have an important role in minimizing the resistance burden among bacterial species.

  4. National surveillance study on carbapenem non-susceptible Klebsiella pneumoniae in Taiwan: the emergence and rapid dissemination of KPC-2 carbapenemase.

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    Sheng-Kang Chiu

    Full Text Available OBJECTIVES: The global spread and increasing incidence of carbapenem non-susceptible Klebsiella pneumoniae (CnSKP has made its treatment difficult, increasing the mortality. To establish nationwide data on CnSKP spread and carbapenem-resistance mechanisms, we conducted a national surveillance study in Taiwanese hospitals. METHODS: We collected 100 and 247 CnSKP isolates in 2010 and 2012, respectively. The tests performed included antibiotic susceptibility tests; detection of carbapenemase, extended-spectrum β-lactamases (ESBL, and AmpC β-lactamases genes; outer membrane porin profiles; and genetic relationship with pulsed-field gel electrophoresis and multilocus sequence type. RESULTS: The resistance rate of CnSKP isolates to cefazolin, cefotaxime, cefoxitin, ceftazidime, and ciprofloxacin was over 90%. Susceptibility rate to tigecycline and colistin in 2010 was 91.0% and 83.0%, respectively; in 2012, it was 91.9% and 87.9%, respectively. In 2010, carbapenemase genes were detected in only 6.0% of isolates (4 bla IMP-8 and 2 bla VIM-1. In 2012, carbapenemase genes were detected in 22.3% of isolates (41 bla KPC-2, 7 bla VIM-1, 6 bla IMP-8, and 1 bla NDM-1. More than 95% of isolates exhibited either OmpK35 or OmpK36 porin loss or both. Impermeability due to porin mutation coupled with AmpC β-lactamases or ESBLs were major carbapenem-resistance mechanisms. Among 41 KPC-2-producing K. pneumoniae isolates, all were ST11 with 1 major pulsotype. CONCLUSIONS: In 2010 and 2012, the major mechanisms of CnSKP in Taiwan were the concomitance of AmpC with OmpK35/36 loss. KPC-2-KP dissemination with the same ST11 were observed in 2012. The emergence and rapid spread of KPC-2-KP is becoming an endemic problem in Taiwan. The identification of NDM-1 K. pneumoniae case is alarming.

  5. Occurrence and antimicrobial resistance of Salmonella spp. isolated from food other than meat in Poland

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    Łukasz Mąka

    2015-09-01

    Full Text Available Introduction and objectives. Antimicrobial resistance of pathogenic bacteria can result in therapy failure, increased hospitalization, and increased risk of death. In Poland, [i]Salmonella[/i] spp. is a major bacterial agent of food poisoning. The majority of studies on antimicrobial resistance in [i]Salmonella[/i] spp. isolates from food have focused on meat products as the source of this pathogen. In comparison, this study examines the antimicrobial susceptibility of [i]Salmonella[/i] spp. isolated from retail food products other than meat in Poland. Materials and Methods. A collection of 122 [i]Salmonella[/i] spp. isolates were isolated in Poland in 2008–2012 from foods other than meat: confectionery products, eggs, fruits, vegetables, spices and others. The resistance of these isolates to 19 antimicrobial agents was tested using the disc diffusion method. Results. [i]Salmonella[/i] Enteritidis was the most frequently identified serotype (84.4% of all tested isolates. In total, 42.6% of the [i]Salmonella[/i] spp. isolates were resistant to antibiotics. The highest frequencies of resistance were observed in isolates from 2009 (60.0% and 2012 (59.5%. Antibiotic resistance was most prevalent among [i]Salmonella[/i] spp. isolated from egg-containing food samples (68.0%. Resistance to nalidixic acid was most common and was observed in 35.2% of all tested isolates. The isolates were less frequently resistant to sulphonamides (6.6%, ampicillin (4.9%, amoxicillin/clavulanic acid (2.5% and to streptomycin, cefoxitin, gentamicin and tetracycline (1.6%. Only one isolate showed resistance to chloramphenicol. Four isolates displayed multiresistance. Conclusions. Although, the level of resistance and multiresistance of [i]Salmonella[/i] spp. isolates from non-meat foods was lower than in those from meat products, the presence of these resistant bacteria poses a real threat to the health of consumers.

  6. The Soil Microbiota Harbors a Diversity of Carbapenem-Hydrolyzing β-Lactamases of Potential Clinical Relevance.

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    Gudeta, Dereje Dadi; Bortolaia, Valeria; Amos, Greg; Wellington, Elizabeth M H; Brandt, Kristian K; Poirel, Laurent; Nielsen, Jesper Boye; Westh, Henrik; Guardabassi, Luca

    2016-01-01

    The origin of carbapenem-hydrolyzing metallo-β-lactamases (MBLs) acquired by clinical bacteria is largely unknown. We investigated the frequency, host range, diversity, and functionality of MBLs in the soil microbiota. Twenty-five soil samples of different types and geographical origins were analyzed by antimicrobial selective culture, followed by phenotypic testing and expression of MBL-encoding genes in Escherichia coli, and whole-genome sequencing of MBL-producing strains was performed. Carbapenemase activity was detected in 29 bacterial isolates from 13 soil samples, leading to identification of seven new MBLs in presumptive Pedobacter roseus (PEDO-1), Pedobacter borealis (PEDO-2), Pedobacter kyungheensis (PEDO-3), Chryseobacterium piscium (CPS-1), Epilithonimonas tenax (ESP-1), Massilia oculi (MSI-1), and Sphingomonas sp. (SPG-1). Carbapenemase production was likely an intrinsic feature in Chryseobacterium and Epilithonimonas, as it occurred in reference strains of different species within these genera. The amino acid identity to MBLs described in clinical bacteria ranged between 40 and 69%. Remarkable features of the new MBLs included prophage integration of the encoding gene (PEDO-1), an unusual amino acid residue at a key position for MBL structure and catalysis (CPS-1), and overlap with a putative OXA β-lactamase (MSI-1). Heterologous expression of PEDO-1, CPS-1, and ESP-1in E. coli significantly increased the MICs of ampicillin, ceftazidime, cefpodoxime, cefoxitin, and meropenem. Our study shows that MBL producers are widespread in soil and include four genera that were previously not known to produce MBLs. The MBLs produced by these bacteria are distantly related to MBLs identified in clinical samples but constitute resistance determinants of clinical relevance if acquired by pathogenic bacteria. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  7. Prevalence of Class I and II Integrons of Methicillin-Resistant Staphylococcus aureus Isolates from Hospitals in Hamadan, Iran

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    Nasim Safari

    2017-05-01

    Full Text Available Background and Objectives: In recent years, the role of integrons has been identified in the transfer of antibiotic resistance genes. The aim of this study was to determine the antibiotic resistance pattern and to identify class I and II integrons and associated gene cassettes in clinical isolates of methicillin-resistant Staphylococcus aureus. Methods: In this descriptive cross-sectional study, 100 isolates of S. aureus were isolated from clinical samples in 2015. After cultivation, the isolates were verified by standard biochemical tests. Then, PCR test was used on nuc gene for final confirmation of the isolates and presence of methicillin-resistance gene. Then, methicillin-resistant isolates were tested for susceptibility to 9 antibiotics. Finally, identification of Class I and II integrons genes and associated gene cassettes was performed on mecA gene using PCR method. Data analysis was carried out using Chi square test. Results: Forty-one out of 100 S. aureus isolates carried mecA gene. The most frequent antibiotic resistance was for cefoxitin and tetracycline (41 and 36 isolates, respectively and the lowest resistance was reported for vancomycin (0. In this study, The prevalence of 38 isolates (92.68% and 3 isolates (7.31% produced class I and II integrons. One type of gene cassette was identified in these isolates, which was related to aadA1 gene cassette. Conclusion: The results of the current study were indicative of high prevalence of antibiotic resistance and class I integrons in S. aureus isolates carrying mecA gene.

  8. Methods of detection and typing of methicillin resistant Staphylococcus aureus isolated from animals

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    Radosavljević V.

    2014-01-01

    Full Text Available In this work there was evaluated the method of detection of methicillin resistant Staphylococcus aureus (MRSA by using two molecular and three phenotypic tests in investigation procedure of 70 strains of S.aureus isolated from animals. Recent findings of the new mecA homologue, mecALGA251, minimise the significance of mecA gene presence detection as a confirmation method of methicillin resistant Staphylococcus aureus identification. For this reason, along with multiplex PCR set of primers(165rDNK, nuc, mecA for detection mecA gene, there was also used multiplex PCR set of primers (spa, mecA, pvl, mecALGA251 for differentiation mecALGA251 from mecA, with simultaneous detection of luk-PV and spa gene fragments. In all 70 investigated isolates there was detected the presence of specific 16 SrDNK fragment and nuc gene which encodes a thermostable S. aureus nuclease, while in 5 out of 70 S. aureus isolates, there was proven mecA gene presence using two multiplex PCR tests. In the investigated strains there was determined neither mecC (mecALGA251gene presence, nor Panton Valentine Leukocidin encoding gene. By application cefoxitin disk-diffusion, latex-agglutination and two multiplex PCR tests, the identical results in identification 5 methicillin resistant out of 70 investigated S. aureus strains were obtained. In our investigation there was determined a complete correlation between the results of phenotypic and genotypic identification of methicillin resistant S. aureus. [Projekat Ministarstva nauke Republike Srbije, br. TR 31079

  9. Prevalence of Panton-Valentine leukocidin genes in community-associated methicillin-resistant Staphylococcus aureus in the district of Pomoravlje

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    Petrović-Jeremić Ljiljana

    2016-01-01

    Full Text Available Background/Aim. Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA strains appear to have rapidly disseminated among population in the community without established risk factors for MRSA worldwide. Panton-Valentine leukocidin (PVL is a cytolytic toxin, encoded by the lukF-PV and lukF-PV genes. PVL may be the key toxin responsible for enhanced virulence of CA-MRSA. The aim of this study was to detect the genes encoding PVL in CA-MRSA isolates from healthy people from the District of Pomoravlje. Methods. We took throat and nose swabs from healthy, employed persons with mandatory sanitary examinations and analyzed the presence of MRSA, between January 2011 and December 2012 in the District of Pomoravlje. Susceptibility of isolated strains to cefoxitin was investigated by using disc diffusion according to the recommendation of CLSI (Clinical Laboratory Standard Institute, and by E test. The presence of penicillin-binding protein 2a (PBP2a in Staphylococci was detected using latex agglutination Slidex ®MRSA Detection test. The gold standard, polymerase chain reaction (PCR assay, was used for detection of mecA gene and PVL gene, and typing of SCCmec region. Results. Our investigation showed that staphylococcal carrier state was present in 2.58% of 52,910 throat and nasal swabs, and in 50 of them (3.67% MRSA was isolated. Among these MRSA, 2 (4% isolates were PVL-positive. Conclusion. The prevalence of CAMRSA and the presence of PVL gene among healthy, employed population in the District of Pomoravlje were low. The values obtained in this study show that, our region is not significantly different from the other parts of our country, nor from the other European countries.

  10. Prevalence and Antimicrobial Susceptibility of Staphylococcus aureus Isolated from Nasal Carriers

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    Hedieh Moradi-Tabriz

    2015-10-01

    Full Text Available Background: Staphylococcus aureus (S. aureus is one of the major virulence factors of hospital and community acquired infections. Healthcare workers can be the host of S.aureus for many months. And it is very important due to the possibility of transmission to patients. Theaim of this study was to determine the prevalence of S.aureus nasal carriers, the antibiotic susceptibility pattern and its effective factors on Sina Hospital workers in Tehran, Iran.Methods: healthcare workers from different wards of Sina Hospital were studied in Tehran, Iran in 2010. Samples were taken from both nostrils of each individual. After 18-24hr incubation, the isolates were evaluated by gram stain, catalase, coagulase, DNase and manitol salt agar bywhich staphylococci were isolated. Disk diffusion antimicrobial susceptibility tests against oxacillin, cefoxitin and vancomycin was performed. Finally, by using PCR, the mecA gene was studied in methicillin-resistant strains (MRSA.Results: 34of the 166 workers, were nasal carriers of S. aureus and one of them was MRSA. The ratio of carriers in operating room workers was more than other wards, without significant relationship (p.value>0.05. S.aureus was found in 34.3% of operating room, 13.8% of nurses and 22.7% of licensed and other personnel. There was a significant relationship betweenoccupations and S.aureus carriage (p.value:0.03.Conclusion: According to the low prevalence of S. aureus and MRSA carriers in Sina hospital, it can be said that the role of the hospital staff as a source of infections caused by S. aureus especially is very low.

  11. Molecular Typing and Antimicrobial Susceptibility of Methicillin-Resistant Staphylococcus aureus Isolated from Bovine Milk in Tanzania

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    Jibril Mohammed

    2018-01-01

    Full Text Available 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.

  12. Relative performance of antimicrobial susceptibility assays on clinical Escherichia coli isolates from animals.

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    Badger, Skye; Abraham, Sam; Saputra, Sugiyono; Trott, Darren J; Turnidge, John; Mitchell, Tahlia; Caraguel, Charles G B; Jordan, David

    2018-02-01

    The assessment of antimicrobial resistance in bacteria derived from animals is often performed using the disc diffusion assay. However broth-microdilution is the preferred assay for national antimicrobial resistance surveillance programs. This study aimed to evaluate the accuracy of disc diffusion relative to broth-microdilution across a panel of 12 antimicrobials using data from a collection of 994 clinical Escherichia coli isolates from animals. Disc diffusion performance was evaluated by diagnostic sensitivity, specificity, likelihood ratio pairs and receive-operating characteristic (ROC) analysis. Data was dichotomised using CLSI susceptible and resistant clinical breakpoints. In addition, disc diffusion breakpoints produced using diffusion Breakpoint Estimation Testing Software (dBETS) were evaluated. Analysis revealed considerable variability in performance estimates for disc diffusion susceptible and resistant breakpoints (AUC ranges: 0.78-0.99 and 0.92-1.0, respectively) across the panel of antimicrobials. Ciprofloxacin, tetracycline, and ampicillin estimates were robust across both breakpoints, whereas estimates for several antimicrobials including amoxicillin-clavulanic acid, cefoxitin and gentamicin were less favourable using susceptible breakpoints. Overall performance estimates were moderately improved when dBETS susceptible breakpoints were applied. For most antimicrobials, disc diffusion was accurate at predicting resistance of clinical E. coli from animals that could otherwise be determined by broth-microdilution. While disc diffusion is suboptimal for assessing the proportion of fully susceptible isolates for some drugs, sensitivity and specificity estimates provided here allow for the use of standard formula to correct this. For this reason, disc diffusion has applicability in national surveillance provided the performance of the assay is taken into account. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Prevalence and Antibiogram Pattern of Some Nosocomial Pathogens Isolated from Hospital Environment in Zaria, Nigeria

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    Chrinius Hammuel

    2014-09-01

    Full Text Available Many ordinary surfaces and hands of healthcare givers in hospitals are sometimes inadequately decontaminated with routine disinfection techniques. It is necessary to determine the distribution of these pathogens in the hospitals. In this study 160 swab samples were collected from ten different surfaces including nurses’ hand swab, Nurses’ table top, door knob/handle, toilet seat, operation table, sink, stretcher, floor, bedrail, and cupboard. Biochemical tests were used to identify the bacteria. Kirby-Bauer-Clinical and Laboratory Standards Institute (CLSI modified single disc diffusion technique was used to determine the antibiogram profile of the pathogens at 0.5 scale McFarland’s standard (1.5 × 108 cells/ml. The total percentage prevalence of Staphylococcus aureus was 50.80%, Pseudomonas aeruginosa 28.60% and Escherichia coli 20.60%. Out of 20.60% of E. coli isolates7.7% were found to be E. coli O157:H7. S. aureus isolates were highly resistant to ampcillin and cefoxitin P. aeruginosa and E. coli were resistant to tetracycline. The multiple antibiotic resistance indexes of the pathogens were more than 0.2. Among the isolates, S. aureus showed more multidrug resistance (31.30% and E. coli had the least multidrug. Frequently touched surfaces within the hospital environment are contaminated by Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus. These pathogens can be transfer from surfaces to patients and to surfaces again through healthcare workers. The widespread use of antimicrobials, especially over- or inappropriate use of antibiotics, has contributed to an increased incidence of antimicrobial-resistant organisms.

  14. Isolation of methicillin-resistant Staphylococcus aureus from small ruminants and their meat at slaughter and retail level in Greece.

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    Sergelidis, D; Papadopoulos, T; Komodromos, D; Sergelidou, E; Lazou, T; Papagianni, M; Zdragas, A; Papa, A

    2015-11-01

    Methicillin-resistant Staphylococcus aureus (MRSA) presents major health risk for humans causing serious nosocomial and community-acquired infections. Asymptomatic food-producing animal carriers and their meat may represent potential reservoirs for human infections. The aim of this study was to investigate the prevalence of MRSA in small ruminants raised under free-range conditions and their meat at slaughter and retail level in Northern Greece. Staphylococcus aureus was isolated from 9·6% of the examined samples. All isolates were resistant at least to one antibiotic, whereas 59·3% of them were multidrug resistant (MDR) exhibiting resistance to three or more antibiotic classes. The higher resistance rates were observed against penicillin (100%), tetracycline (74%), clindamycin (59·3%) and erythromycin (51·9%). Resistance to cefoxitin was exhibited by 22·2% of the isolates, but only one isolate was found to carry the mecA gene and belonged to spa type t127. This is the first time this type of Staph. aureus is isolated in Greece from the surface of a small ruminant's carcass. The presence of multidrug resistant Staph. aureus, and especially MRSA, in small ruminants and their meat, represents a potential threat for the spread of this pathogen in the community. This study is the first report on methicillin-resistant Staphylococcus aureus in small ruminants and their meat at slaughter level in Greece, elucidating a possible vehicle food for transmission to humans. These results suggest that human or animal sources could be involved in meat contamination and thus sources of contamination require investigation to control the dispersion of MRSA in the community. © 2015 The Society for Applied Microbiology.

  15. Incidence, Antimicrobial Susceptibility, and Toxin Genes Possession Screening of Staphylococcus aureus in Retail Chicken Livers and Gizzards

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    Lubna S. Abdalrahman

    2015-04-01

    Full Text Available Few recent outbreaks in Europe and the US involving Campylobacter and Salmonella were linked to the consumption of chicken livers. Studies investigating Staphylococcus aureus in chicken livers and gizzards are very limited. The objectives of this study were to determine the prevalence, antimicrobial resistance, and virulence of S. aureus and MRSA (Methicillin-Resistant Staphylococcus aureus in retail chicken livers and gizzards in Tulsa, Oklahoma. In this study, 156 chicken livers and 39 chicken gizzards samples of two brands were collected. While one of the brands showed very low prevalence of 1% (1/100 for S. aureus in chicken livers and gizzards, the second brand showed prevalence of 37% (31/95. No MRSA was detected since none harbored the mecA or mecC gene. Eighty seven S. aureus isolates from livers and 28 from gizzards were screened for antimicrobial resistance to 16 antimicrobials and the possession of 18 toxin genes. Resistance to most of the antimicrobials screened including cefoxitin and oxacillin was higher in the chicken gizzards isolates. While the prevalence of enterotoxin genes seg and sei was higher in the gizzards isolates, the prevalence of hemolysin genes hla, hlb, and hld was higher in the livers ones. The lucocidin genes lukE-lukD was equally prevalent in chicken livers and gizzards isolates. Using spa typing, a subset of the recovered isolates showed that they are not known to be livestock associated and, hence, may be of a human origin. In conclusion, this study stresses the importance of thorough cooking of chicken livers and gizzards since it might contain multidrug resistant enterotoxigenic S. aureus. To our knowledge this is the first study to specifically investigate the prevalence of S. aureus in chicken livers and gizzards in the US.

  16. Diverse modulation of spa transcription by cell wall active antibiotics in Staphylococcus aureus

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    Nielsen Lene N

    2012-08-01

    Full Text Available Abstract Background The aim of this study was to investigate the effect of various classes of clinically relevant antibiotics at sub-lethal concentrations on virulence gene expression and biofilm formation in Staphylococcus aureus. Findings LacZ promoter fusions of genes related to staphylococcal virulence were used to monitor the effects of antibiotics on gene expression in a disc diffusion assay. The selected genes were hla and spa encoding α-hemolysin and Protein A, respectively and RNAIII, the effector molecule of the agr quorum sensing system. The results were confirmed by quantitative real-time PCR. Additionally, we monitored the effect of subinhibitory concentrations of antibiotics on the ability of S. aureus to form biofilm in a microtiter plate assay. The results show that sub-lethal antibiotic concentrations diversely modulate expression of RNAIII, hla and spa. Consistently, expression of all three genes were repressed by aminoglycosides and induced by fluoroquinolones and penicillins. In contrast, the β-lactam sub-group cephalosporins enhanced expression of RNAIII and hla but diversely affected expression of spa. The compounds cefalotin, cefamandole, cefoxitin, ceftazidime and cefixine were found to up-regulate spa, while down-regulation was observed for cefuroxime, cefotaxime and cefepime. Interestingly, biofilm assays demonstrated that the spa-inducing cefalotin resulted in less biofilm formation compared to the spa-repressing cefotaxime. Conclusions We find that independently of the cephalosporin generation, cephalosporins oppositely regulate spa expression and biofilm formation. Repression of spa expression correlates with the presence of a distinct methyloxime group while induction correlates with an acidic substituted oxime group. As cephalosporines target the cell wall penicillin binding proteins we speculate that subtle differences in this interaction fine-tunes spa expression independently of agr.

  17. Clostridium difficile infection diagnosis in a paediatric population: comparison of methodologies.

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    Hart, J; Putsathit, P; Knight, D R; Sammels, L; Riley, T V; Keil, A

    2014-09-01

    The increasing incidence of Clostridium difficile infection (CDI) in paediatric hospitalised populations, combined with the emergence of hypervirulent strains, community-acquired CDI and the need for prompt treatment and infection control, makes the rapid, accurate diagnosis of CDI crucial. We validated commonly used C. difficile diagnostic tests in a paediatric hospital population. From October 2011 to January 2012, 150 consecutive stools were collected from 75 patients at a tertiary paediatric hospital in Perth, Western Australia. Stools were tested using: C. Diff Quik Chek Complete, Illumigene C. difficile, GeneOhm Cdiff, cycloserine cefoxitin fructose agar (CCFA) culture, and cell culture cytotoxin neutralisation assay (CCNA). The reference standard was growth on CCFA or Cdiff Chromagar and PCR on isolates to detect tcdA, tcdB, cdtA, and cdtB. Isolates were PCR ribotyped. The prevalence of CDI was high (43 % of patients). Quik Chek Complete glutamate dehydrogenase (GDH) demonstrated a low negative predictive value (NPV) (93 %). Both CCNA and Quik Chek Complete toxin A/B had poor sensitivity (33 % and 29 % respectively). Molecular methods both had 89 % sensitivity. Algorithms using GDH + Illumigene or GeneOhm reduced the sensitivity to 85 % and 83 % respectively. Ribotype UK014/20 predominated. GDH NPV and GeneOhm and Illumigene sensitivities were reduced compared with adult studies. Quik Chek Complete and CCNA cannot reliably detect toxigenic CDI. A GDH first algorithm showed reduced sensitivity. In a high prevalence paediatric population, molecular methods alone are recommended over the use of GDH algorithm or culture and CCNA, as they demonstrate the best test performance characteristics.

  18. Factors associated with the occurrence of MRSA CC398 in herds of fattening pigs in Germany

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    Alt Katja

    2011-11-01

    Full Text Available Abstract Background The purpose of this study was to investigate the prevalence of MRSA in herds of fattening pigs in different regions of Germany, and to determine factors associated with the occurrence of this pathogen. For this purpose pooled dust samples were collected, and a questionnaire covered information regarding herd characteristics and management practices. Samples were pre-enriched in high-salt medium followed by selective enrichment containing cefoxitin/aztreonam, and culturing. Presumptive colonies were confirmed by multiplex-PCR targeting nuc-, mecA- and 16S rRNA-genes. Isolates were spa- and SCCmec-, and in selected cases, multilocus sequence-typed. Susceptibilities to 13 antimicrobials were determined by broth microdilution. Statistical analysis was carried out using backward stepwise logistic regression to calculate odds ratios with the MRSA test result as the outcome and herd characteristics as categorical covariates. Results Overall, 152 of 290 (52% fattening pig farms tested positive for MRSA. The prevalence in the east, north- and south-west of Germany ranged from 39 to 59%. t011 (66% and t034 (23% were the most commonly identified spa-types, and 85% of isolates carried SCCmec Type V. Identified spa-types were all associated with clonal complex CC398. Susceptibility testing revealed that all isolates were resistant to tetracycline. High resistance rates were also found for sulfamethoxazole/trimethoprim (40%, and quinupristin/dalfopristin (32%. In addition, 83% of strains displayed multidrug resistant (> 3 substance classes phenotypes. Logistic regression revealed herd size (large farms OR: 5.4; CI: 2.7-11.2; p Conclusions MRSA CC398 is widely distributed among herds of fattening pigs in Germany. Farm management plays a crucial role in the dissemination of MRSA with herd size, and production type representing potential major indicators.

  19. Characterization of pig-associated methicillin-resistant Staphylococcus aureus.

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    Li, Jun; Jiang, Nansong; Ke, Yuebin; Feßler, Andrea T; Wang, Yang; Schwarz, Stefan; Wu, Congming

    2017-03-01

    Livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) have been reported in various countries worldwide. However, although China is one of the biggest pig and pork producers, large-scale studies on pig-associated LA-MRSA from China are scarce. The aims of this study were to analyze 2420 non-duplicate samples collected from pigs at swine farms and slaughterhouses in different regions in China during 2014 for the prevalence of pig-associated MRSA and to determine the antimicrobial resistance pheno- and genotypes of the respective isolates. MRSA isolates were identified in 270 (11.2%) samples. The isolates were characterized by antimicrobial susceptibility testing, multilocus sequence typing (MLST), spa typing, pulsed-field gel electrophoresis (PFGE) and screening for resistance genes. All MRSA isolates belonged to the clonal complex 9 and spa type t899, but showed variable PFGE patterns. All isolates were non-susceptible to oxacillin, cefoxitin, clindamycin, chloramphenicol, florfenicol, ciprofloxacin, and valnemulin. High rates of resistance were also observed for tetracycline (99.6%), erythromycin (97.0%), quinupristin-dalfopristin (97.0%), and gentamicin (80.4%). Three linezolid-non-susceptible isolates containing the multi-resistance gene cfr and nine rifampicin-non-susceptible isolates with mutations in rpoB were detected. Resistance to β-lactams was exclusively associated with mecA, while phenicol resistance was mainly attributable to fexA, except in the three cfr-positive isolates. The pleuromutilin-lincosamide-streptogramin A resistance gene lsa(E) was identified in all MRSA isolates, and no other pleuromutilin resistance genes, except cfr in three isolates, were detected. Pigs are the most important hosts of LA-MRSA in China. Screening for pig-associated MRSA is necessary to monitor changes in epidemiology and characteristics of these important pathogens. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Factors associated with the occurrence of MRSA CC398 in herds of fattening pigs in Germany.

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    Alt, Katja; Fetsch, Alexandra; Schroeter, Andreas; Guerra, Beatriz; Hammerl, Jens A; Hertwig, Stefan; Senkov, Natalja; Geinets, Anna; Mueller-Graf, Christine; Braeunig, Juliane; Kaesbohrer, Annemarie; Appel, Bernd; Hensel, Andreas; Tenhagen, Bernd-Alois

    2011-11-10

    The purpose of this study was to investigate the prevalence of MRSA in herds of fattening pigs in different regions of Germany, and to determine factors associated with the occurrence of this pathogen. For this purpose pooled dust samples were collected, and a questionnaire covered information regarding herd characteristics and management practices. Samples were pre-enriched in high-salt medium followed by selective enrichment containing cefoxitin/aztreonam, and culturing. Presumptive colonies were confirmed by multiplex-PCR targeting nuc-, mecA- and 16S rRNA-genes. Isolates were spa- and SCCmec-, and in selected cases, multilocus sequence-typed. Susceptibilities to 13 antimicrobials were determined by broth microdilution. Statistical analysis was carried out using backward stepwise logistic regression to calculate odds ratios with the MRSA test result as the outcome and herd characteristics as categorical covariates. Overall, 152 of 290 (52%) fattening pig farms tested positive for MRSA. The prevalence in the east, north- and south-west of Germany ranged from 39 to 59%.t011 (66%) and t034 (23%) were the most commonly identified spa-types, and 85% of isolates carried SCCmec Type V. Identified spa-types were all associated with clonal complex CC398. Susceptibility testing revealed that all isolates were resistant to tetracycline. High resistance rates were also found for sulfamethoxazole/trimethoprim (40%), and quinupristin/dalfopristin (32%). In addition, 83% of strains displayed multidrug resistant (> 3 substance classes) phenotypes.Logistic regression revealed herd size (large farms OR: 5.4; CI: 2.7-11.2; p pig operations. MRSA CC398 is widely distributed among herds of fattening pigs in Germany. Farm management plays a crucial role in the dissemination of MRSA with herd size, and production type representing potential major indicators.

  1. Misidentification of methicillin-resistant Staphylococcus aureus (MRSA in hospitals in Tripoli, Libya

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    Mohamed O. Ahmed

    2010-11-01

    Full Text Available Background: Methicillin-resistant Staphylococcus aureus (MRSA is a nosocomial (hospital-acquired pathogen of exceptional concern. It is responsible for life-threatening infections in both the hospital and the community. Aims: To determine the frequency of MRSA misidentification in hospitals in Tripoli, Libya using current testing methods. Methods: One hundred and seventy S. aureus isolates previously identified as MRSA were obtained from three hospitals in Tripoli. All isolates were reidentified by culturing on mannitol salt agar, API 20 Staph System and retested for resistance to methicillin using the cefoxitin disk diffusion susceptibility test and PBP2a. D-tests and vancomycin E-tests (Van-E-tests were also performed for vancomycin-resistant isolates. Results: Of the 170 isolates examined, 86 (51% were confirmed as MRSA (i.e. 49% were misidentified as MRSA. Fifteen (17% of the confirmed MRSA strains exhibited inducible clindamycin resistance. Of the 86 confirmed MRSA isolates, 13 (15% were resistant to mupirocin, 53 (62% were resistant to ciprofloxacin, 41 (48% were resistant to trimethoprim-sulfamethoxazole, and none were resistant to linezolid. Although disc-diffusion testing indicated that 23 (27% of the isolates were resistant to vancomycin, none of the isolates were vancomycin-resistant by Van-E-test. Conclusions: Misidentification of nosocomial S. aureus as MRSA is a serious problem in Libyan hospitals. There is an urgent need for the proper training of microbiology laboratory technicians in standard antimicrobial susceptibility procedures and the implementation of quality control programs in microbiology laboratories of Libyan hospitals.

  2. 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.

  3. Prevalence of methicillin-resistant Staphylococcus aureus skin and nasal carriage isolates from bovines and its antibiogram

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    Alok Kumar

    2017-06-01

    Full Text Available Aim: This study was conducted to determine the prevalence of methicillin-resistant Staphylococcus aureus (MRSA in cattle and buffalo and to study their antibiotic resistance pattern. Materials and Methods: A total of 136 samples (skin and nasal swab from cattle and buffalo were collected. MRSA was identified by conventional bacterial culture techniques which were further confirmed by amplification of S. aureus-specific 16S rRNA by polymerase chain reaction (PCR. The isolates were further analyzed for the presence of mecA gene by PCR. The antimicrobial susceptibility profiling was performed by disc diffusion method. Results: The prevalence of MRSA in the current study was 28.57% and 34.28% in cattle nasal and skin swab, respectively, with an overall prevalence of 31.43% MRSA among cattle. Buffalo nasal and skin sample showed MRSA prevalence of 54.55% and 39.4%, respectively, with 46.9% overall prevalence. PCR could detect mecA gene in 36.4% and 58% MRSA isolates from cattle and buffalo, respectively. Antimicrobial susceptibility test found MRSA resistant to penicillin and oxytetracycline (88% each, cefoxitin (75%, cotrimoxazole (62%, and amoxyclav (50%. 100% sensitivity was observed against ciprofloxacin, amikacin, chloramphenicol, and gentamicin. Three (16.7% MRSA isolates from buffalo were found resistant to vancomycin. Conclusion: Cattle and buffalo were identified as a potential carrier of MRSA in Bihar (India. The isolation of vancomycinresistant S. aureus (VRSA in the current study indicates the emergence of VRSA in animal population which may be transmitted to the human beings working in close contact to the animals.

  4. Characterisation of drug resistance of nosocomial ESBL-producing E. coli isolates obtained from a Turkish university hospital between 2009 and 2012 by pulsed field gel electrophoresis and antibiotic resistance tests.

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    Karagöz, Alper; Sunnetcioglu, Mahmut; Ceylan, Mehmet Resat; Bayram, Yasemin; Yalcin, Gozde; Kocak, Nadir; Suvak, Burak; Andac, Cenk A

    2016-01-01

    In this study, drug resistance of 28 ESBL-producing Escherichia coli isolates obtained from 144 patients hospitalized at the Yüzüncüyil University Hospital at Van (YUH), Turkey, between 2009 and 2012 were characterized by pulsed field gel electrophoresis and antibiotic susceptibility tests. Antibiotic resistance profile was determined by Phoenix automated system (BD, USA). The ratio of ESBL-producing E. coli strains was determined to be 19.4% (28 out of 144 E. coli isolates). It was determined that the anaesthesiology, paediatrics and thoracic medicine intensive care units in YUH were cross-contaminated between 2009 and 2012 by ESBL-producing E. coli strains, which is a sign of nosocomial infection in YUH. Analysis of PFGE results gave rise to two main PFGE profiles, profile-A with four subprofiles and profile-B with three subprofiles, where profile-A predominates over profile-B (14%). Comparison of the antibiotic resistance profile with the PFGE profile yielded similarities while some differences also exist due to either identical restriction enzyme cutting sites with slightly different genetic sequences in between the cutting sites or newly formed restriction enzyme cutting sites that do not affect antibiotic resistance genes. Enterobacteriaceae, particularly E. coli, have developed resistance in YUH by producing ESBLs against oxyimino and non-oxyimino cephalosporins, and penicillin-type antibiotics. Therefore, more effective antibiotics such as cefoxitin or cefoperazone-sulbactam should be used for the treatment of future nosocomial infections in YUH while hospital staff should take care with hygiene, such as hand washing.

  5. CLINICAL ISOLATES OF MECA, METHICILLIN, VANCOMYCIN RESISTANCE S. AUREUS; ESBLs PRODUCING K.PNEUMONIA, E.COLI, P. AUREGENOSA FROM VARIOUS CLINICAL SOURCE AND ITS ANTIMICROBIAL RESISTANCE PATTERNS

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    Ismail Mahmud Ali, Amirthalingam R

    2015-01-01

    Full Text Available Background and Objective: Antimicrobial resistance has turned into a key medical and public health crisis globally since the injudicious use of magic bullets (drugs. Aim of this study is focused on the clinical isolate and their percentages of resistant to antibiotics in gram positive bacteria such as MRSA, VRSA, and MSSA are common causes of nosocomical, skin structure infections, bacteremia and infection of other systems; ESBLs producing Enterobacteriaceae (E. coli, Klebsiella spp. is common agent of urinary tract, bloodstream, pulmonary and intra-abdominal infections and carbapenem resistant P. aeruginosa with its complete antimicrobial patterns which are currently practiced in this population. Methods: There are one hundred and fourteen (114 various clinical isolates, isolated from various clinical samples like throat swab, urine, pus, sputum, and blood culture, identified as specific isolate with resistance patterns were analyzed by BD phoenix-100 the auto analyzer. Results: Off 114 clinical isolate, 6 mecA-mediated resistance (cefoxitin>8mgc/ml, 11 methicillin resistance, 18 β lactam/βlactamase inhibitor, 12 methicillin sensitive and 3 vancomycin (>16µg/ml resistance S. aureus have been isolated from overall 50 isolate of S.aureus. In addition, there are 27 P.aeruginosa, 15 ESBLs from overall of 25 K. pneumoniae and 7 ESBLs out of 12 Escherichia coli species have been isolated. The resistance and susceptibility pattern percentages have been graphically represented for each isolates. Conclusion: Current study revealed that the drug classes of β lactam/βlactamase inhibitor having high resistance rate with S.aureus, P.aureginosa, K. pneumoniae and E. coli isolate. Also, some of other drug classes such as cepham and tetracycline having higher resistance rate with P.aureginosa and K.pneumoniae. In addition, the vancomycin resistances S. aureus have been isolated and reported as first time in this population.

  6. Phenotypic and genotypic characterization of antibiotic resistance of methicillin-resistant Staphylococcus aureus isolated from hospital food

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    Farhad Safarpoor Dehkordi

    2017-10-01

    Full Text Available Abstract Background Pathogenic biotypes of the Methicillin-resistant Staphylococcus aureus (MRSA strains are considered to be one of the major cause of food-borne diseases in hospitals. The present investigation was done to study the pattern of antibiotic resistance and prevalence of antibiotic resistance genes of different biotypes of the MRSA strains isolated from various types of hospital food samples. Methods Four-hundred and eighty-five raw and cooked hospital food samples were cultured and MRSA strains were identified using the oxacillin and cefoxitin disk diffusion tests and mecA-based PCR amplification. Isolated strains were subjected to biotyping and their antibiotic resistance patterns were analyzed using the disk diffusion and PCR methods. Results Prevalence of S. aureus and MRSA were 9.69 and 7.62%, respectively. Meat and chicken barbecues had the highest prevalence of MRSA. Prevalence of bovine, ovine, poultry and human-based biotypes in the MRSA strains were 8.10, 8.10, 32.43 and 48.64%, respectively. All of the MRSA strains recovered from soup, salad and rice samples were related to human-based biotypes. MRSA strains harbored the highest prevalence of resistance against penicillin (100%, ceftaroline (100%, tetracycline (100%, erythromycin (89.18% and trimethoprim-sulfamethoxazole (83.78%. TetK (72.97%, ermA (72.97%, msrA (64.86% and aacA-D (62.16% were the most commonly detected antibiotic resistance genes. Conclusions Pattern of antibiotic resistance and also distribution of antibiotic resistance genes were related to the biotype of MRSA strains. Presence of multi-drug resistance and also simultaneous presence of several antibiotic resistance genes in some MRSA isolates showed an important public health issue Further researches are required to found additional epidemiological aspects of the MRSA strains in hospital food samples.

  7. In vitro activity of tigecycline against clinical isolates of carbapenem resistant Acinetobacter baumannii complex in Pretoria, South Africa.

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    Ahmed, Nahid H; Baba, Kamaldeen; Clay, Cornelis; Lekalakala, Ruth; Hoosen, Anwar A

    2012-05-03

    The presence of multi-drug resistant Acinetobacter baumannii raises a big therapeutic challenge in our hospital. Tigecycline, a new glycylcycline with expanded broad spectrum of activity against multi-drug resistant organisms was recently licensed in South Africa. The aim of this study was to evaluate the in vitro activity of tigecycline against carbapenem resistant A. baumannii complex. Consecutive clinical isolates of carbapenem resistant A. baumannii complex were collected between February and July 2010. Species identification and susceptibility testing was performed by Vitek-2 colorimetric compact system with Advanced Expert System (AES). Strains were tested for carbapenemase production by the modified Hodge test, according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. A total of 232 carbapenem resistant clinical isolates of A. baumannii complex were collected over the six months study period; 217 (93.5%) of these were modified Hodge test positive. All isolates were susceptible to colistin and 174 (78%) susceptible to amikacin whilst 20 (9%) were susceptible to ciprofloxacin. For tigecycline 169 (75.8%) were fully susceptible, 37 (16.6%) intermediately resistant and only 17 (7.6%) were fully resistant. None of the carbapenem resistant isolates were susceptible to ampicillin, amoxicillin/clavullanic acid, piperacillin/tazobactam, cefuroxime, cefuroxime axetil, cefoxitin, cefepime or nitrofurantoin. All carbapenem resistant isolates were found to be fully susceptible to colistin; amikacin and tigecycline susceptibility was 78% and 76% respectively. Treatment options for infections due to carbapenem and multi-drug resistant A. baumannii organisms are limited and hence tigecycline and amikacin may be considered. The properties of tigecycline i.e. stability, safety, low toxicity, non cross-resistance with other antibiotics and its efficacy against multi-drug resistant A. baumannii isolates make it a good choice. However, ongoing monitoring of

  8. Investigation of fnBP and clf genes prevalence among Methicillin-resistant Staphylococcus aureus strains and assessment of the effects of host factors and clinical specimens on their distribution

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    Elmira Shafaei

    2017-06-01

    Full Text Available Background & Objective: Staphylococcus aureus is a common cause of nosocomial infections that has several specific adhesion molecules factors which can be bound to a variety of host matrix extracellular proteins and replaced by host tissues. This binding is mediated by a family of proteins known as microbial surface components known as adhesive matrix molecules (MSCRAMMs which includes fibronectin-binding protein (FnBP and fibrinogen binding protein (Clf. Comprehensive studies regarding the genetic abilities of S. aureus isolates especially MRSA which have binding mediators seem essential. Materials & Methods: In this study 74572 clinical samples of blood, urine, sputum and other clinical samples of patients who were admitted to Tehran Milad Hospital were collected. 180 Staphylococcus aureus strains were identified after diagnostic tests. In order to determine MRSA isolates Cefoxitin disc diffusion method was used. The presence and frequency of fnbA, fnbB and clf genes was determined by PCR. Results: From 180 Staphylococcus aureus strains 159 strains (88% had fnbA gene,47 strains (26% had fnbB gene and 36 strains (20% had clf gene. The simultaneous frequency of fnbA and fnbB was 42 (23%, fnbA and Clf was 32 (18% and fnbB and Clf was 9 (5%. The presence of all three genes together was 9 (5%. Conclusion: The results showed that there was no significant relationship between fnbA, fnbB and clf genes and clinical sample type, gender and age of patients and MRSA and MSSA isolates.

  9. Virulence Genes and Antimicrobial Resistance in Escherichia coli from Cheese Made from Unpasteurized Milk in Brazil.

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    de Campos, Anna C L P; Puño-Sarmiento, Juan J; Medeiros, Leonardo P; Gazal, Luís E S; Maluta, Renato Pariz; Navarro, Armando; Kobayashi, Renata K T; Fagan, Eder P; Nakazato, Gerson

    2018-02-01

    Cow raw milk cheese is widely eaten in Brazil. These products may be contaminated with pathogenic bacteria. In this work, we investigated the presence of Escherichia coli in raw milk cheese from different States in Brazil. From 147 "Minas" cheese samples, 28 cheeses were positive for E. coli. Among 39 E. coli isolates of the cheeses, one was positive for eae and negative for bpfA and efa1/lifA using PCR, and so was classified as atypical Enteropathogenic E. coli (aEPEC). Two other isolates were positive for extraintestinal pathogenic E. coli (ExPEC) genes. The aEPEC isolate belongs to serogroup O127 and was classified in A phylogenetic group, and ExPEC isolates were found in O73:H12 (EC-2 strain) and O64474:H8 (EC-9 strain) serotype. This ExPEC belongs to A and C phylogenetic group, respectively. Most of E. coli strains belonged to Clermont phylogenetic groups A (28.2%), C, and E (23.1%). Six strains (15.4%) of E. coli were positive for group B1 and two (5.1%) for B2. E. coli isolates presented an aggregative (46.0%) and diffuse (12.6%) adherence pattern to HeLa cells, and the other isolates did not show adhesion (41.4%). Four E. coli isolates (10.3%) were shown to produce moderate biofilm. The antimicrobial resistance rate was tetracycline (25.6%), followed by ampicillin (17.9%), cefoxitin (7.7%), nalidixic acid (5.1%), and amoxicillin-clavulanic acid (2.6%). One strain was resistant to three antimicrobials (tetracycline, ampicillin, and nalidixic acid). The presence of these microorganisms, the O127 strain, and a new serogroup in Brazil is a potential risk for public health.

  10. Prevalence of antimicrobial resistance in fecal Escherichia coli and Salmonella enterica in Canadian commercial meat, companion, laboratory, and shelter rabbits (Oryctolagus cuniculus) and its association with routine antimicrobial use in commercial meat rabbits.

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    Kylie, Jennifer; McEwen, Scott A; Boerlin, Patrick; Reid-Smith, Richard J; Weese, J Scott; Turner, Patricia V

    2017-11-01

    Antimicrobial resistance (AMR) in zoonotic (e.g. Salmonella spp.), pathogenic, and opportunistic (e.g. E. coli) bacteria in animals represents a potential reservoir of antimicrobial resistant bacteria and resistance genes to bacteria infecting humans and other animals. This study evaluated the prevalence of E. coli and Salmonella enterica, and the presence of associated AMR in commercial meat, companion, research, and shelter rabbits in Canada. Associations between antimicrobial usage and prevalence of AMR in bacterial isolates were also examined in commercial meat rabbits. Culture and susceptibility testing was conducted on pooled fecal samples from weanling and adult commercial meat rabbits taken during both summer and winter months (n=100, 27 farms), and from pooled laboratory (n=14, 8 laboratory facilities), companion (n=53), and shelter (n=15, 4 shelters) rabbit fecal samples. At the facility level, E. coli was identified in samples from each commercial rabbit farm, laboratory facility, and 3 of 4 shelters, and in 6 of 53 companion rabbit fecal samples. Seventy-nine of 314 (25.2%; CI: 20.7-30.2%) E. coli isolates demonstrated resistance to >1 antimicrobial agent. At least one E. coli isolate resistant to at least one antimicrobial agent was present in samples from 55.6% of commercial farms, and from 25% of each laboratory and shelter facilities, with resistance to tetracycline being most common; no resistance was identified in companion animal samples. Salmonella enterica subsp. was identified exclusively in pooled fecal samples from commercial rabbit farms; Salmonella enterica serovar London from one farm and Salmonella enterica serovar Kentucky from another. The S. Kentucky isolate was resistant to amoxicillin/clavulanic acid, ampicillin, cefoxitin, ceftiofur, ceftriaxone, streptomycin, and tetracycline, whereas the S. London isolate was pansusceptible. Routine use of antimicrobials on commercial meat rabbit farms was not significantly associated with the

  11. Bacteriologic profile and antibiogram of blood culture isolates from a children's hospital in Kabul.

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    Tariq, Tariq Mahmud

    2014-06-01

    To identify the bacterial pathogens causing paediatric septicaemia in Kabul and to determine their antibiogram to improve empirical antibiotic therapy. Cross-sectional study. Microbiology Laboratory of FMIC, Kabul, Afghanistan, from January 2010 to June 2012. Blood cultures from suspected cases of sepsis were processed in BD (Becton Dickinson, USA) for culture BACTEC™ 9240 Blood Culture System. Positive growths were examined and isolates were identified by conventional biochemical tests. Bacteria were identified to the species level using various Analytical Profile Index (API) identification strips. Antibiotic susceptibility testing was performed by modified Kirby-Bauer disk diffusion method. Drug resistant strains were studied for extended spectrum beta lactamase (ESBL) production by combination disk method and for methicillin resistant Staphylococcus aureus (MRSA) by Cefoxitin disk diffusion method. Out of a total 3360 blood cultures received from in-patients, 410 yielded monomicrobial growth; hence the frequency of positive blood culture was 12.2%. Out of a total 410 isolates, 212 (51.71%) were gram-negative bacilli and 184 (44.88%) were gram-positive cocci. In addition, 14 (3.41%) Candida species were also isolated. The frequently isolated species of gram-negative bacteria belonged to Enterobacteriaceae and included 66 Klebsiella (16.1%), 42 Enterobacter (10.2%), 35 Escherichia (E.) coli (8.5%) and 16 Serratia (3.9%) species. In addition, 21 (5.12%) Pseudomonas species were also isolated. Correspondingly, amongst gram-positive cocci, the most frequently isolated species were 108 coagulase-negative Staphylococci (26.34%) followed by 49 Staphylococcus aureus (11.95%) and 21 Streptococcus species (5.12%). Among gram-negative isolates, those that produced ESBL i.e., 110 out of 212 (51.9%) were found to be multidrug-resistant and showed high resistance to commonly used antibiotics namely Ampicillin, Gentamicin, 3rd generation Cephalosporins, Fluoroquinolones and

  12. [Characteristics of epidemiology and antimicrobial resistance of gram-negative bacterial bloodstream infections in children].

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    Dong, L; Zhang, X Y; Li, C C; Li, Z; Xia, Y Q

    2017-09-02

    Objective: To study the epidemiology and antimicrobial resistance of Gram-negative bacterial bloodstream infections in children, and to guide the choice of antimicrobials and the control of nosocomial infection. Method: Clinical data, bacteriology and antimicrobial susceptibility test results were collected retrospectively in hospitalized children who were diagnosed with gram-negative bacterial bloodstream infections in Yuying Children's Hospital of Wenzhou Medical University from January, 2010 to December, 2015. Result: A total of 399 cases (253 male and 146 female) were identified. The age ranged from 16 hours to 16 years (median age 10.1 months). The majority of cases were collected from division of neonatology ( n =261, 65.4%), followed by 31 cases (7.8%) from pediatric intensive care unit and 29 cases (7.3%) from Gastroenterology Department; 275 cases (68.9%) had underlying diseases, mainly including preterm birth( n =172), neonatal respiratory distress syndrome( n =67) and newborn asphyxia( n =53). Eighty cases had received invasive procedures and 20 had surgical operation; 149 cases (37.3%) were community-acquired and 250 cases (62.7%) were hospital acquired. Fifty cases had complications, among those, 40 cases had septic shock, 32 cases had multiple organ dysfunction syndrome and 7 cases had disseminated intravascular coagulation; 288 cases were cured, 48 improved, 17 gave up treatment and discharged, and 46 died; totally 408 strains were isolated from 399 children, including Enterobacteriaceae (346, 84.8%), non-fermentative Gram-negative bacteria (49, 12.0%) and other gram-negative bacteria (13, 3.2%). The resistance rates of Escherichia coli ( n =175) and Klebsiella pneumoniae ( n =106) to carbapenems, β-lactams enzyme and its inhibitors, amikacin and cefoxitin were all lower than 10%. Totally 245 multi-drug resistant strains (60.1%) were isolated, including 225 strains of Enterobacteriaceae and 18 strains of non-fermentative Gram-negative bacteria ( P

  13. [Antimicrobial resistance characteristics of and disinfectant-resistant gene distribution in Staphylococcus aureus isolates from male urogenital tract infection].

    Science.gov (United States)

    Ye, Jian-Zhong; Yu, Xiao; Li, Xiao-Si; Sun, Yao; Li, Mei-Mei; Zhang, Wei; Fan, Hao; Cao, Jian-Ming; Zhou, Tie-Li

    2014-07-01

    To study the antibiotic- and disinfectant-resistance features of and disinfectant-resistant gene distribution in Staphylococcus aureus (Sa) isolated from the urogenital tract of male patients with urogenital tract infection (UTI). total of 152 Sa isolates were collected from the urethral discharge specimens from male UTI patients. The minimum inhibition concentration (MIC) of antimicrobial agents and disinfectants commonly used against Sa were tested by standard ager dilution; the methicillin-resistant Sa (MRSA) isolates detected by cefoxitin disk diffusion and mecA gene amplification; Staphylococcal cassette chromosome mec (SCCmec) genotyping performed by multiplex PCR; the disinfectants gene qac (quaternary ammonium compound) amplified by PCR; and the clonal relatedness of qacA/B-positive MRSA isolates investigated by pulsed-field gel electrophoresis (PFGE). Out of the 152 Sa isolates, 91 (59.9%) were found to be MRSA. SCCmec genotyping showed SCCmec V to be the main type, accounting for 63.7% (58/91), with 8 (8.8%) isolates of SCCmec I, 2 (2.2%) isolates of SCCmec II, 19 (20.9%) isolates of SCCmec III, and 4 (4. 4%) isolates of SCCmec IV. The Sa isolates exhibited high rates of non-susceptibility to penicillin (95.4%) , erythromycin (72.4% ) , ciprofloxacin (42. 8%), and levofloxacin (44.7%), and a fairly high sensitivity to nitrofurantoin, teicoplanin, linezolid, and vancomycin. The MIC in the Sa isolates was 0. 25 -16 microg/ml for chlorhexidine; MIC50 and MIC90 were 2.0 and 4.0 microg/ml respectively for MRSA strains and both 1.0 microg/ml for MSSA strains. Out of the 152 Sa isolates, 72 (47.4%) harbored the qacA/B gene, 6 (3.9%) the smar (qacC + qacD) gene, 9 (5.9%) the qacE delta 1 gene, and 2 (1.3%) the qacH gene, but no qacG and qacJ genes were detected. PFGE analysis showed that the qacA/B-positive MRSA isolates were distributed Clinical Sa isolates exhibited varied degrees of resistance to commonly used antibiotics, and in a polyclonal manner. some

  14. 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

  15. Tigecycline Susceptibility Trends Among Pathogens Isolated from Complicated Skin and Soft-Tissue Infections in North and Latin America: 2012–2016

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    Hoban, Daryl; Renteria, Martha; Leister-Tebbe, Heidi; Sahm, Dan

    2017-01-01

    Abstract Background The Tigecycline Evaluation Surveillance Trial (TEST) monitors the activity of tigecycline and other antimicrobials against clinically-relevant pathogens collected globally. This study reports the activity of tigecycline (TGC) against Gram-positive and Gram-negative isolates collected in North and Latin America from patients with complicated skin and soft-tissue infections (CSSTI). Methods Hospital sites from North America (NA) and Latin America (LA) collected non-duplicate clinical Gram-positive and -negative isolates from various complicated skin and skin structure infection sources during 2012–2016. Organism identification and antibiotic susceptibility (S) testing was performed by the local laboratories. Susceptibility testing was determined using the broth microdilution method according to CLSI guidelines and categorical interpretation of results was done using CLSI or FDA (tigecycline) breakpoint criteria where appropriate. Cefoxitin disk testing was performed for all S. aureus to determine methicillin susceptibility (i.e., MRSA and MSSA). Results The table provides %S and MIC90 data for TGC against CSSTI isolates Region, n, %S, MIC 90 (µg/ml) North America Latin America Organism n %S MIC 90 n %S MIC 90 S. aureus 2270 100 0.12 310 100 0.25 Enterobacter spp. 925 96.4 1 159 92.5 2 P. aeruginosa 758 na* > 8 165 na > 8 E. coli 716 99.9 0.25 241 100 0.25 Enterococcus spp. 691 99.3 0.12 135 100 0.12 S. agalactiae 503 100 0.12 58 100 0.06 K. pneumoniae 471 94.9 2 152 91.5 2 S. marcescens 347 96.8 2 67 97.0 2 A. baumannii 310 na* 2 97 na 1 K. oxytoca 204 99.0 0.5 15 100 1 *na = not applicable or no breakpoints available for this species. Conclusion Based on %S and MIC90 data TGC exhibited potent activity against isolates of all organism groups from complicated skin and soft-tissue infections, regardless of the geographic region. However, given the potential many of these organisms have for developing resistance, continued and careful

  16. The carriage of antibiotic resistance by enteric bacteria from imported tokay geckos (Gekko gecko) destined for the pet trade

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    Casey, Christine L. [Southeastern Cooperative Wildlife Disease Study, Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA 30602 (United States); Hernandez, Sonia M., E-mail: shernz@uga.edu [Southeastern Cooperative Wildlife Disease Study, Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA 30602 (United States); Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602 (United States); Yabsley, Michael J. [Southeastern Cooperative Wildlife Disease Study, Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA 30602 (United States); Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602 (United States); Smith, Katherine F. [Department of Ecology and Evolutionary Biology, Brown University, Providence, RI 02912 (United States); Sanchez, Susan [The Athens Veterinary Diagnostic Laboratory, Athens, GA 30602 (United States); The Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602 (United States)

    2015-02-01

    The emergence of antibiotic-resistant bacteria is a growing public health concern and has serious implications for both human and veterinary medicine. The nature of the global economy encourages the movement of humans, livestock, produce, and wildlife, as well as their potentially antibiotic-resistant bacteria, across international borders. Humans and livestock can be reservoirs for antibiotic-resistant bacteria; however, little is known about the prevalence of antibiotic-resistant bacteria harbored by wildlife and, to our knowledge, limited data has been reported for wild-caught reptiles that were specifically collected for the pet trade. In the current study, we examined the antibiotic resistance of lactose-positive Enterobacteriaceae isolates from wild-caught Tokay geckos (Gekko gecko) imported from Indonesia for use in the pet trade. In addition, we proposed that the conditions under which wild animals are captured, transported, and handled might affect the shedding or fecal prevalence of antibiotic resistance. In particular we were interested in the effects of density; to address this, we experimentally modified densities of geckos after import and documented changes in antibiotic resistance patterns. The commensal enteric bacteria from Tokay geckos (G. gecko) imported for the pet trade displayed resistance against some antibiotics including: ampicillin, amoxicillin/clavulanic acid, cefoxitin, chloramphenicol, kanamycin and tetracycline. There was no significant difference in the prevalence of antibiotic-resistant bacteria after experimentally mimicking potentially stressful transportation conditions reptiles experience prior to purchase. There were, however, some interesting trends observed when comparing Tokay geckos housed individually and those housed in groups. Understanding the prevalence of antibiotic resistant commensal enteric flora from common pet reptiles is paramount because of the potential for humans exposed to these animals to acquire antibiotic

  17. Mycobacterium icosiumassiliensis sp. nov., a New Member in the Mycobacterium terrae Complex Isolated from Surface Water in Algeria.

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    Djouadi, Lydia N; Levasseur, Anthony; Khalil, Jacques Bou; Blanc-Taileur, Caroline; Asmar, Shady; Ghiloubi, Wassila; Natèche, Farida; Drancourt, Michel

    2016-08-01

    An acid-fast, rapidly growing, rod-shaped microorganism designated 8WA6 was isolated from a lake in Algiers, Algeria. The lake water was characterized by a temperature of 18 °C, a pH of 7.82, a copper concentration of 8.6 µg/L, and a cadmium concentration of 0.6 µg/L. First-line molecular identification confirmed the 8WA6 isolate to be a member of the Mycobacterium terrae complex, sharing 99.4 % 16S rRNA gene sequence similarity with M. arupense AR-30097, 98.2 % partial hsp65 gene sequence similarity with M. terrae 28K766, and 97.1 % partial rpoB gene sequence similarity with Mycobacterium sp. FI-05396. Its 4.89-Mb genome exhibits a 66.8 GC % and an average nucleotide identity of 64.5 % with M. tuberculosis, 70.5 % with M. arupense, and 75 % with M. asiaticum. In the M. terrae complex, Mycobacterium 8WA6 was unique in exhibiting growth at 42 °C, negative reaction for nitrate reduction, urease activity and Tween 80 hydrolysis, and a positive reaction for α-glucosidase and β-glucosidase. Its protein profile determined by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry revealed a unique spectrum similar to M. arupense and M. terrae, exhibiting eleven specific peaks at 3787.791, 4578.019, 6349.630, 6855.638, 7202.310, 8149.608, 8775.257, 10,224.588, 10,484.116, 12,226.379, and 12,636.871 m/z. Minimal inhibitory concentrations (MIC) for antibiotics, determined by microdilution, indicated a broad spectrum resistance, except for rifabutin (MIC, 0.5 g/L) and cefoxitin (MIC, 16 g/L). We concluded that the 8WA6 isolate is a representative isolate of a previously undescribed species in the M. terrae complex, which was named M. icosiumassiliensis sp. nov. with strain 8WA6 (Collection de Souches de l'Unité des Rickettsies, CSUR P1561, Deutsche Sammlung von Mikroorganismen und Zellkulturen, DSM 100711) as the type strain.

  18. Phenotype, genotype, and antibiotic susceptibility of Swedish and Thai oral isolates of Staphylococcus aureus

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    Susanne Blomqvist

    2015-04-01

    Full Text Available Objective: The present study investigated phenotypes, virulence genotypes, and antibiotic susceptibility of oral Staphylococcus aureus strains in order to get more information on whether oral infections with this bacterium are associated with certain subtypes or related to an over-growth of the S. aureus variants normally found in the oral cavity of healthy carriers. Materials and methods: A total number of 157 S. aureus strains were investigated. Sixty-two strains were isolated from Swedish adults with oral infections, 25 strains were from saliva of healthy Swedish dental students, and 45 strains were from tongue scrapings of HIV-positive subjects in Thailand, and 25 Thai strains from non-HIV controls. The isolates were tested for coagulase, nitrate, arginine, and hemolysin, and for the presence of the virulence genes: hlg, clfA, can, sdrC, sdrD, sdrE, map/eap (adhesins and sea, seb, sec, tst, eta, etb, pvl (toxins. MIC90 and MIC50 were determined by E-test against penicillin V, oxacillin, amoxicillin, clindamycin, vancomycin, fusidic acid, and cefoxitin. Results: While the hemolytic phenotype was significantly (p<0.001 more common among the Thai strains compared to Swedish strains, the virulence genes were found in a similar frequency in the S. aureus strains isolated from all four subject groups. The Panton-Valentine leukocidin (PVL genotype was found in 73–100% of the strains. More than 10% of the strains from Swedish oral infections and from Thai HIV-positives showed low antibiotic susceptibility, most commonly for clindamycin. Only three methicillin-resistant S. aureus (MRSA strains were identified, two from oral infections and one from a Thai HIV patient. Conclusions: S. aureus is occasionally occurring in the oral cavity in both health and disease in Sweden and Thailand. It is therefore most likely that S. aureus in opportunistic oral infections originate from the oral microbiota. S. aureus should be considered in case of oral

  19. Comparison of the Prevalences and Antimicrobial Resistances of Escherichia coli Isolates from Different Retail Meats in the United States, 2002 to 2008

    Science.gov (United States)

    Blickenstaff, K.; Bodeis-Jones, S.; Gaines, S. A.; Tong, E.; McDermott, P. F.

    2012-01-01

    Escherichia coli isolates were recovered from the National Antimicrobial Resistance Monitoring System retail meat program and examined for antimicrobial susceptibility. Retail meat samples (n = 11,921) from four U.S. states collected during 2002 to 2008, consisting of 2,988 chicken breast, 2,942 ground turkey, 2,991 ground beef, and 3,000 pork chop samples, were analyzed. A total of 8,286 E. coli isolates were recovered. The greatest numbers of samples contaminated with the organism were chicken (83.5%) and turkey (82.0%), followed by beef (68.9%) and pork (44.0%). Resistance was most common to tetracycline (50.3%), followed by streptomycin (34.6%), sulfamethoxazole-sulfisoxazole (31.6%), ampicillin (22.5%), gentamicin (18.6%), kanamycin (8.4%), amoxicillin-clavulanic acid (6.4%), and cefoxitin (5.2%). Less than 5% of the isolates had resistance to trimethoprim, ceftriaxone, ceftiofur, nalidixic acid, chloramphenicol, and ciprofloxacin. All isolates were susceptible to amikacin. Compared to beef and pork isolates, the poultry meat isolates had a greater percentage of resistance to all tested drugs, with the exception of chloramphenicol, to which pork isolates had the most resistance. More than half of the turkey isolates (56%) were resistant to multidrugs (≥3 classes) compared to 38.9% of chicken, 17.3% of pork, and 9.3% of beef isolates. The blaCMY gene was present in all ceftriaxone- and ceftiofur-resistant isolates. The cmlA, flo, and catI genes were present in 45%, 43%, and 40% of chloramphenicol-resistant isolates, respectively. Most nalidixic acid-resistant isolates (98.5%) had a gyrA mutation in S83 or D87 or both, whereas only 6.7% had a parC mutation in either S80 or E84. The results showed that E. coli was commonly present in the retail meats, and antimicrobial resistance profiles differed according to the animal origin of the isolates. PMID:22247155

  20. Patterns of infections, aetiological agents and antimicrobial resistance at a tertiary care hospital in northern Tanzania.

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    Kumburu, Happiness Houka; Sonda, Tolbert; Mmbaga, Blandina Theophil; Alifrangis, Michael; Lund, Ole; Kibiki, Gibson; Aarestrup, Frank M

    2017-04-01

    To determine the causative agents of infections and their antimicrobial susceptibility at a tertiary care hospital in Moshi, Tanzania, to guide optimal treatment. A total of 590 specimens (stool (56), sputum (122), blood (126) and wound swabs (286)) were collected from 575 patients admitted in the medical and surgical departments. The bacterial species were determined by conventional methods, and disc diffusion was used to determine the antimicrobial susceptibility pattern of the bacterial isolates. A total of 249 (42.2%) specimens were culture-positive yielding a total of 377 isolates. A wide range of bacteria was isolated, the most predominant being Gram-negative bacteria: Proteus spp. (n = 48, 12.7%), Escherichia coli (n = 44, 11.7%), Pseudomonas spp. (n = 40, 10.6%) and Klebsiella spp (n = 38, 10.1%). Wound infections were characterised by multiple isolates (n = 293, 77.7%), with the most frequent being Proteus spp. (n = 44, 15%), Pseudomonas (n = 37, 12.6%), Staphylococcus (n = 29, 9.9%) and Klebsiella spp. (n = 28, 9.6%). All Staphylococcus aureus tested were resistant to penicillin (n = 22, 100%) and susceptible to vancomycin. Significant resistance to cephalosporins such as cefazolin (n = 62, 72.9%), ceftriaxone (n = 44, 51.8%) and ceftazidime (n = 40, 37.4%) was observed in Gram-negative bacteria, as well as resistance to cefoxitin (n = 6, 27.3%) in S. aureus. The study has revealed a wide range of causative agents, with an alarming rate of resistance to the commonly used antimicrobial agents. Furthermore, the bacterial spectrum differs from those often observed in high-income countries. This highlights the imperative of regular generation of data on aetiological agents and their antimicrobial susceptibility patterns especially in infectious disease endemic settings. The key steps would be to ensure the diagnostic capacity at a sufficient number of sites and implement structures to routinely exchange, compare, analyse and report data. Sentinel sites

  1. Occurrence of Extended Spectrum β-Lactamases, KPC-Type, and MCR-1.2-Producing Enterobacteriaceae from Wells, River Water, and Wastewater Treatment Plants in Oltrepò Pavese Area, Northern Italy.

    Science.gov (United States)

    Caltagirone, Mariasofia; Nucleo, Elisabetta; Spalla, Melissa; Zara, Francesca; Novazzi, Federica; Marchetti, Vittoria M; Piazza, Aurora; Bitar, Ibrahim; De Cicco, Marica; Paolucci, Stefania; Pilla, Giorgio; Migliavacca, Roberta; Pagani, Laura

    2017-01-01

    To evaluate the water compartment antibiotic-resistance contamination rates, 11 wells, five streams, and four treatment plants located in the Oltrepò Pavese area were screened for the presence of third generation cephalosporins resistant Gram-negative bacteria. Enterobacteriaceae were also characterized for the Extended-Spectrum-β-Lactamases (ESBLs), carbapenemases, and mcr-1 genes presence. From December 2014 to November 2015, 246 water samples were filtered, plated on Plate Count Agar, MacConkey Agar, and MacConkey Agar with cefotaxime. Isolates were species identified using AutoSCAN-4-System and ESBLs, carbapenemases, and colistin resistance determinants were characterized by PCR, sequencing, and microarray. Plasmid conjugative transfer experiments, PCR-based Replicon typing, Pulsed-Field Gel Electrophoresis, Multi-Locus-Sequence-Typing, and in-silico plasmid characterization were performed. A total of 132 enterobacteria isolates grew on MacConkey agar with cefotaxime: 82 (62.1%) were obtained from streams, 41 (31.1%) from treatment plants, and 9 (6.8%) from wells. Thirty out of 132 (22.7%) isolates, mainly belonging to Escherichia coli ( n = 15) species, showed a synergic effect with piperacillin-tazobactam. A single ESBL gene of bla CTX-M -type was identified in 19/30 isolates. In further two E. coli strains, a bla CTX-M-1 gene co-existed with a bla SHV -type ESBL determinant. A bla SHV-12 gene was detected in two isolates of E. coli ( n = 1) and Klebsiella oxytoca ( n = 1), while any ESBL determinant was ascertained in seven Yersinia enterocolitica strains. A bla DHA -type gene was detected in a cefoxitin resistant Y. enterocolitica from a stream. Interestingly, two Klebsiella pneumoniae strains of ST307 and ST258, collected from a well and a wastewater treatment plant, resulted KPC-2, and KPC-3 producers, respectively. Moreover, we report the first detection of mcr-1.2 ST10 E. coli on a conjugative IncX4 plasmid (33.303 bp in size) from a stream of Oltrep

  2. Occurrence of Extended Spectrum β-Lactamases, KPC-Type, and MCR-1.2-Producing Enterobacteriaceae from Wells, River Water, and Wastewater Treatment Plants in Oltrepò Pavese Area, Northern Italy

    Directory of Open Access Journals (Sweden)

    Mariasofia Caltagirone

    2017-11-01

    Full Text Available To evaluate the water compartment antibiotic-resistance contamination rates, 11 wells, five streams, and four treatment plants located in the Oltrepò Pavese area were screened for the presence of third generation cephalosporins resistant Gram-negative bacteria. Enterobacteriaceae were also characterized for the Extended-Spectrum-β-Lactamases (ESBLs, carbapenemases, and mcr-1 genes presence. From December 2014 to November 2015, 246 water samples were filtered, plated on Plate Count Agar, MacConkey Agar, and MacConkey Agar with cefotaxime. Isolates were species identified using AutoSCAN-4-System and ESBLs, carbapenemases, and colistin resistance determinants were characterized by PCR, sequencing, and microarray. Plasmid conjugative transfer experiments, PCR-based Replicon typing, Pulsed-Field Gel Electrophoresis, Multi-Locus-Sequence-Typing, and in-silico plasmid characterization were performed. A total of 132 enterobacteria isolates grew on MacConkey agar with cefotaxime: 82 (62.1% were obtained from streams, 41 (31.1% from treatment plants, and 9 (6.8% from wells. Thirty out of 132 (22.7% isolates, mainly belonging to Escherichia coli (n = 15 species, showed a synergic effect with piperacillin-tazobactam. A single ESBL gene of blaCTX−M-type was identified in 19/30 isolates. In further two E. coli strains, a blaCTX−M−1 gene co-existed with a blaSHV-type ESBL determinant. A blaSHV−12 gene was detected in two isolates of E. coli (n = 1 and Klebsiella oxytoca (n = 1, while any ESBL determinant was ascertained in seven Yersinia enterocolitica strains. A blaDHA-type gene was detected in a cefoxitin resistant Y. enterocolitica from a stream. Interestingly, two Klebsiella pneumoniae strains of ST307 and ST258, collected from a well and a wastewater treatment plant, resulted KPC-2, and KPC-3 producers, respectively. Moreover, we report the first detection of mcr-1.2 ST10 E. coli on a conjugative IncX4 plasmid (33.303 bp in size from a stream of

  3. Occurrence of blaDHA-1mediated cephalosporin resistance in Escherichia coli and their transcriptional response against cephalosporin stress: a report from India.

    Science.gov (United States)

    Ingti, Birson; Paul, Deepjyoti; Maurya, Anand Prakash; Bora, Debajyoti; Chanda, Debadatta Dhar; Chakravarty, Atanu; Bhattacharjee, Amitabha

    2017-03-21

    Treatment alternatives for DHA-1 harboring strains are challenging as it confers resistance to broad spectrum cephalosporins and may further limit treatment option when expressed at higher levels. Therefore, this study was designed to know the prevalence of DHA genes and analyse the transcription level of DHA-1 against different β-lactam stress. Screening of AmpC β-lactamase phenotypically by modified three dimensional extract method followed by Antimicrobial Susceptibility and MIC determination. Genotyping screening of β-lactamase genes was performed by PCR assay followed by their sequencing. The bla DHA-1 transcriptional response was evaluated under different cephalosporin stress by RT PCR. Transferability of bla DHA gene was performed by transformation and conjugation and plasmid incompatibility typing, DNA fingerprinting by enterobacterial repetitive intergenic consensus sequences PCR. 16 DHA-1 genes were screened positive from 176 Escherichia coli isolates and primer extension analysis showed a significant increase in DHA-1 mRNA transcription in response to cefotaxime at 8 µg/ml (6.99 × 10 2 fold), ceftriaxone at 2 µg/ml (2.63 × 10 3 fold), ceftazidime at 8 µg/ml (7.06 × 10 3 fold) and cefoxitin at 4 µg/ml (3.60 × 10 4 fold) when compared with untreated strain. These transcription data were found significant when analyzed statistically using one way ANOVA. Four different ESBL genes were detected in 10 isolates which include CTX-M (n = 6), SHV (n = 4), TEM (n = 3) and OXA-10 (n = 1), whereas, carbapenemase gene (NDM) was detected only in one isolate. Other plasmid mediated AmpC β-lactamases CIT (n = 9), EBC (n = 2) were detected in nine isolates. All DHA-1 genes detected were encoded in plasmid and incompatibility typing from the transformants indicated that the plasmid encoding bla DHA-1 was carried mostly by the FIA and L/M Inc group. This study demonstrates the prevalence of DHA-1 gene in this region and highlights high

  4. Update of incidence and antimicrobial susceptibility trends of Escherichia coli and Klebsiella pneumoniae isolates from Chinese intra-abdominal infection patients.

    Science.gov (United States)

    Zhang, Hui; Yang, Qiwen; Liao, Kang; Ni, Yuxing; Yu, Yunsong; Hu, Bijie; Sun, Ziyong; Huang, Wenxiang; Wang, Yong; Wu, Anhua; Feng, Xianju; Luo, Yanping; Chu, Yunzhuo; Chen, Shulan; Cao, Bin; Su, Jianrong; Duan, Qiong; Zhang, Shufang; Shao, Haifeng; Kong, Haishen; Gui, Bingdong; Hu, Zhidong; Badal, Robert; Xu, Yingchun

    2017-12-18

    . Susceptibilities to all cephalosporins and fluoroquinolones were less than 50% beside 66.5% and 56.07% to cefoxitin (FOX) for ESBL+ Escherichia coli and Klebsiella pneumoniae strains respectively. The total ESBL+ rates decreased in Escherichia coli and Klebsiella pneumoniae IAI isolates due to fewer prevalence in HA infections. IPM, ETP and AMK were the most effective antimicrobials against ESBL+ Escherichia coli and Klebsiella pneumoniae IAI isolates in 2012-2014 and a change of fluoroquinolone regimens for Chinese IAIs is recommended.

  5. Antibiotic Resistance and Toxin Production of Clostridium difficile Isolates from the Hospitalized Patients in a Large Hospital in Florida.

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    Peng, Zhong; Addisu, Anteneh; Alrabaa, Sally; Sun, Xingmin

    2017-01-01

    Clostridium difficile is an important cause of nosocomial acquired antibiotic-associated diarrhea causing an estimated 453,000 cases with 29,000 deaths yearly in the U.S. Both antibiotic resistance and toxin expression of C. difficile correlate with the severity of C. difficile infection (CDI). In this report, a total of 139 C. difficile isolates from patients diagnosed with CDI in Tampa General Hospital (Florida) in 2016 were studied for antibiotic resistance profiles of 12 types of antibiotics and toxin production. Antibiotic resistance determined by broth microdilution method showed that strains resistant to multi-antibiotics are common. Six strains (4.32%) showed resistance to six types of antibiotics. Twenty strains (14.39%) showed resistance to five types of antibiotics. Seventeen strains (12.24%) showed resistance to four types of antibiotics. Thirty-nine strains (28.06%) showed resistance to three types of antibiotic. Thirty-four strains (24.46%) showed resistance to two types of antibiotics. While, all isolates were susceptible to metronidazole, and rifaximin, we found that one isolate (0.72%) displayed resistance to vancomycin (MIC ≥ 8 μg/ml), and another one was resistant to fidaxomicin (MIC >1 μg/ml). The percentage of isolates resistant to cefoxitin, ceftriaxone, chloramphenicol, ampicillin, clindamycin, erythromycin, gatifloxacin, and moxifloxacin was 75.54, 10.79, 5.76, 67.63, 82.70, 45.32, 28.06, and 28.78%, respectively. Toxin profiling by PCR showed the isolates include 101 (72.66%) A+B+CDT-strains, 23 (16.55%) A+B+CDT+ strains, 3 (2.16%) A-B+CDT+ strains, 1 (0.72%) A-B+CDT-strains, and 11 (7.91%) A-B-CDT-strains. Toxin production determined by ELISA using supernatants of bacterial culture harvested at 12, 24, 48, and 72 h of post inoculation (hpi) showed that the toxins were mainly produced between 48 and 72 hpi, and toxin B (TcdB) was produced faster than toxin A (TcdA) during the experimental time (72 hpi). In addition, the binary

  6. Vancomycin heteroresistance in coagulase negative Staphylococcus blood stream infections from patients of intensive care units in Mansoura University Hospitals, Egypt.

    Science.gov (United States)

    Mashaly, Ghada El-Saeed; El-Mahdy, Rasha Hassan

    2017-09-19

    Vancomycin heteroresistance in coagulase negative Staphylococci (CoNS) is a recent health concern especially in serious infections like bloodstream infections as it may lead to failure of therapy. Little information is available about the prevalence vancomycin heteroresistance in CoNS causing bloodstream infections in intensive care units (ICUs) patients of Mansoura University Hospitals (MUHs). This prospective study enrolled 743 blood samples collected from ICUs patients presented with clinical manifestations of bloodstream infections over the period extending from January 2014 to March 2016. Samples were processed, coagulase negative Staphylococci were identified by routine microbiological methods and the absence of coagulase activity. Species were identified by API Staph 32. Oxacillin resistant CoNS were identified by cefoxitin disc diffusion method. Susceptibility testing of isolated CoNS to vancomycin was carried out using vancomycin agar dilution method. Mec A gene detection by PCR was done for oxacillin resistant isolates. Screening for vancomycin heteroresistance was done on brain heart infusion (BHI) agar containing 4 μg/mL vancomycin. Confirmation of vancomycin heteroresistance was carried out by population analysis profile (PAP). A total of 58 isolates were identified as CoNS from patients of clinically suspected bloodstream infections. The identified species were 33 (56.9%) Staphylococcus epidermidis, 12 (20.7%) Staphylococcus capitis, 7 (12.1%) Staphylococcus haemolyticus, and 3 isolates (5.2%) Staphylococcus lugdunesis. Three isolates were unidentified by API Staph 32. Forty-four (75.9%) isolates were oxacillin resistant. Mec A gene was detected in all oxacillin resistant isolates. All isolates had susceptible vancomycin MICs by agar dilution. Nine isolates (15.5%) could grow on BHI agar containing 4 μg/mL vancomycin. These isolates showed heterogeneous profile of resistance to vancomycin by population analysis profile. Vancomycin heteroresistant

  7. Detection and characterization of extended-spectrum β-lactamase-producing Escherichia coli from chicken production chains in Nigeria.

    Science.gov (United States)

    Ojo, Olufemi E; Schwarz, Stefan; Michael, Geovana B

    2016-10-15

    A total of 405 Escherichia coli from the chicken production chains in Nigeria were investigated for ESBL-production and 4 isolates were identified as ESBL producers. They were characterized by XbaI-PFGE, multilocus sequence typing (MLST), phylotyping, sequencing of porin and regulatory genes and of the regulatory region of chromosomal ampC genes. Transformed ESBL gene-carrying plasmids were characterized by S1-nuclease, replicon typing, conjugation, digestion and PCRs for detection of the genetic environment of ESBL genes. Susceptibility testing, PCRs for the resistance genes, integrons, and the DNA microarray were performed with both, the original isolates and the transformants. All ESBL-producing isolates harboured bla CTX-M-15 genes located on non-conjugative plasmids (120-155kb). Three isolates with closely related/indistinguishable XbaI-patterns belonged to phylogroup A, and MLST sequence type ST10 and the fourth to phylogroup D and ST405. Resistance to aminoglycosides, sulfonamides/trimethoprim, quinolones, and tetracyclines were seen in all isolates. Incompatibility group IncFIB bla CTX-M-15 -carrying plasmids were detected in the three related isolates which carried also a class 1 integron (aadA2-orfF-dfrA12) and the resistance genes bla OXA-1 , bla TEM-1 , aac(3')-IIa, aac(6')-Ib-cr, sul1, sul2, and tet(A). The IncFIA-IncFIB-IncI1 bla CTX-M-15 -carrying plasmid harboured additionally the resistance genes aac(3')-IIa and tet(B). The bla CTX-M-15 genes were associated with ISEcp1 and Δorf477. ESBL-producing isolates showed elevated MICs to cefoxitin (16-64mg/L) and ertapenem MICs (0.5-2.0mg/L) mainly due to alterations in the porin genes. The virulence genes astA and prfB were detected. Although a low prevalence of ESBL-producing isolates was found, co-located resistance genes on the ESBL gene-carrying plasmids may facilitate the dissemination of them. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Prevalence of β-Lactamase Producing Escherichia coli from Retail Meat in Turkey.

    Science.gov (United States)

    Pehlivanlar Önen, Sevda; Aslantaş, Özkan; Şebnem Yılmaz, Ebru; Kürekci, Cemil

    2015-09-01

    Extended spectrum β-lactamase (ESBL) and plasmid-mediated AmpC β-lactamase (pAmpC) producing Escherichia coli have been shown to be present in humans and animals representing a significant problem worldwide. This study aimed to search the presence of ESBL and/or AmpC-producing E. coli in retail meats (chicken and beef) in Turkey. A total of 88 β-lactamase-producing E. coli were isolated from chicken (n = 81/100) and beef meat (n = 7/100) samples and their susceptibility to several antimicrobials were tested using disc diffusion method. E. coli isolates were further characterized for their phylogenetic groups. β-Lactamase encoding (blaTEM , blaSHV , blaOXA , blaCTX-M , and blaAmpC ) and quinolone resistance genes (qnrA, qnrB, qnrS, qepA, and acc(6')-Ib-cr) were also secreened by polymerase chain reaction (PCR). However, in regard to β-lactamase genes, 84 of 88 isolates were positive for blaCTX-M-1 (n = 39), blaCTX-M-3 (n = 5), blaCTX-M-15 (n = 4), blaTEM-1b (n = 2), blaSHV-12 (n = 1), blaCTX-M-1 /blaTEM-1b (n = 10), blaCTX-M-1 /blaTEM-1b /blaSHV-5 (n = 1), blaCTX-M-1 /blaCMY-2 (n = 1) and blaTEM-1b /blaCMY-2 (n = 6), blaCTX-M-15 /blaSHV-12 (n = 1), blaCTX-M-15 /blaTEM-1b (n = 1), blaTEM-1b /blaSHV-12 (n = 1), and blaCMY-2 (n = 12) genes. Resistance to cefuroxime (75.6% and 85.7%), nalidixic acid (89% and 85.7%), tetracycline (91.4% and 100%), streptomycin (40.2% and 100%), and trimethoprim-sulfamethoxazole (36.6% and 85.7%) was observed among strains isolated from chicken and beef, respectively. However, all isolates were found to be susceptible to amikacin, imipenem, and cefepime. Resistance to ampicillin and cefoxitin was significantly linked to blaCMY-2 gene, while there was a significant correlation between CTX-M type ESBL and antimicrobial resistance to cefuroxime and streptomycin (P meats are highly contaminated with ESBL-producing E. coli implementing a great risk to human health in Turkey. © 2015 Institute of Food Technologists®

  9. Prevalence and clonal relationship of ESBL-producing Salmonella strains from humans and poultry in northeastern Algeria.

    Science.gov (United States)

    Djeffal, Samia; Bakour, Sofiane; Mamache, Bakir; Elgroud, Rachid; Agabou, Amir; Chabou, Selma; Hireche, Sana; Bouaziz, Omar; Rahal, Kheira; Rolain, Jean-Marc

    2017-05-15

    The aims of this study were to investigate Salmonella contamination in broiler chicken farms and slaughterhouses, to assess the antibiotic resistance profile in avian and human Salmonella isolates, and to evaluate the relationship between avian and human Extended Spectrum β-Lactamase (ESBL)-producing isolates. Salmonella was screened in different sample matrices collected at thirty-two chicken farms and five slaughterhouses. The human isolates were recovered from clinical specimens at the University Teaching Hospital of Constantine (UTH). All suspected colonies were confirmed by MALDI-TOF (Matrix Assisted Laser Desorption Ionization Time OF light) and serotyped. Susceptibility testing against 13 antibiotics including, amoxicillin/clavulanic acid, ticarcillin, cefoxitin, cefotaxime, aztreonam, imipenem, ertapenem, gentamicin, amikacin, ciprofloxacin, colistin, trimethoprim/sulfamethoxazole and fosfomycin, was performed using the disk diffusion method on Mueller-Hinton agar. ESBL-production was screened by the double-disk synergy test and confirmed by molecular characterization using PCR (polymerase chain reaction) amplification and sequencing of ESBL encoding genes. Clonality of the avian and human strains was performed using the Multi Locus Sequencing Typing method (MLST). Forty-five isolated avian Salmonella strains and 37 human collected ones were studied. Five S. enterica serotypes were found in avian isolates (mainly Kentucky) and 9 from human ones (essentially Infantis). 51.11% and 26.6% of the avian isolates were resistant to ciprofloxacin and cefotaxime, respectively, whereas human isolates were less resistant to these antibiotics (13.5% to ciprofloxacin and 16.2% to cefotaxime). Eighteen (12 avian and 6 human) strains were found to produce ESBLs, which were identified as bla CTX-M-1 (n = 12), bla CTX-M-15 (n = 5) and bla TEM group (n = 8). Interestingly, seven of the ESBL-producing strains (5 avian and 2 human) were of the same ST (ST15) and

  10. The carriage of antibiotic resistance by enteric bacteria from imported tokay geckos (Gekko gecko) destined for the pet trade

    International Nuclear Information System (INIS)

    Casey, Christine L.; Hernandez, Sonia M.; Yabsley, Michael J.; Smith, Katherine F.; Sanchez, Susan

    2015-01-01

    The emergence of antibiotic-resistant bacteria is a growing public health concern and has serious implications for both human and veterinary medicine. The nature of the global economy encourages the movement of humans, livestock, produce, and wildlife, as well as their potentially antibiotic-resistant bacteria, across international borders. Humans and livestock can be reservoirs for antibiotic-resistant bacteria; however, little is known about the prevalence of antibiotic-resistant bacteria harbored by wildlife and, to our knowledge, limited data has been reported for wild-caught reptiles that were specifically collected for the pet trade. In the current study, we examined the antibiotic resistance of lactose-positive Enterobacteriaceae isolates from wild-caught Tokay geckos (Gekko gecko) imported from Indonesia for use in the pet trade. In addition, we proposed that the conditions under which wild animals are captured, transported, and handled might affect the shedding or fecal prevalence of antibiotic resistance. In particular we were interested in the effects of density; to address this, we experimentally modified densities of geckos after import and documented changes in antibiotic resistance patterns. The commensal enteric bacteria from Tokay geckos (G. gecko) imported for the pet trade displayed resistance against some antibiotics including: ampicillin, amoxicillin/clavulanic acid, cefoxitin, chloramphenicol, kanamycin and tetracycline. There was no significant difference in the prevalence of antibiotic-resistant bacteria after experimentally mimicking potentially stressful transportation conditions reptiles experience prior to purchase. There were, however, some interesting trends observed when comparing Tokay geckos housed individually and those housed in groups. Understanding the prevalence of antibiotic resistant commensal enteric flora from common pet reptiles is paramount because of the potential for humans exposed to these animals to acquire antibiotic

  11. Prevalence and antimicrobial resistance profile of Staphylococcus in dairy farms, abattoir and humans in Addis Ababa, Ethiopia.

    Science.gov (United States)

    Beyene, Takele; Hayishe, Halefom; Gizaw, Fikru; Beyi, Ashenafi Feyisa; Abunna, Fufa; Mammo, Bedaso; Ayana, Dinka; Waktole, Hika; Abdi, Reta Duguma

    2017-04-28

    Staphylococcus species cause mastitis and wound infection in livestock and food poisoning in humans through ingestion of contaminated foods, including meat and dairy products. They are evolving pathogens in that they readily acquire drug resistance, and multiple drug-resistant (MDR) isolates are increasing in human and veterinary healthcare. Therefore, this study was conducted to evaluate the prevalence of Staphylococci and their drug resistance in dairy farms and abattoir settings of Addis Ababa. In this cross-sectional study, 193 samples of milk, meat, equipment and humans working in the dairy farms and abattoir were collected (dairy farms = 72 and abattoir sources = 121). Staphylococcus isolation and identification at the species level was done according to ISO-6888-3 using biochemical characteristics. An antimicrobial susceptibility test was conducted for 43 of the isolates using 15 antimicrobial agents commonly used for humans and livestock by the Kirby Bauer disk diffusion method following CLSI guidelines. Staphylococcus organism were isolated from 92 (47.7%) of the total 193 samples, 50% in the dairy farms and 46.3% in the abattoir. The isolated species were S. aureus (n = 31; 16.1%), S. intermedius (n = 21; 10.9%), S. hyicus (n = 16; 8.3%), and coagulase negative Staphylococcus (CNS) (n = 24; 12.4%). Gentamycin was effective drug as all isolates (n = 43; 100%) were susceptible to it and followed by kanamycin (n = 39; 90.7%). However, the majority of the isolates showed resistance to penicillin-G (95.3%), nalidixic acid (88.4%), cloxacillin (79.1%), vancomycin (65.1%) and cefoxitin (55.8%). Of the 15 S. aureus tested for drug susceptibility, 73.3% of them were phenotypically resistant to vancomycin (VRSA) and all of the 15 isolates showed multi-drug resistance (MDR) to >3 drugs. Also, all of the tested CNS (100%), S. hyicus (100%) and the majority of S. intermedius isolates (88.9%) developed MDR. Alarmingly, the Staphylococcus isolates

  12. Antimicrobial susceptibility and molecular typing of methicillin-resistant staphylococcus aureus in retail foods in Shaanxi, China.

    Science.gov (United States)

    Wang, Xin; Li, Guanghui; Xia, Xiaodong; Yang, Baowei; Xi, Meili; Meng, Jianghong

    2014-04-01

    The aims of this study were to evaluate the occurrence of methicillin-resistant Staphylococcus aureus (MRSA) in retail foods in Shaanxi, China and to investigate antimicrobial resistance and molecular characteristics of these strains. A total of 1979 retail food samples were randomly collected during 2008-2012 from supermarkets and farmers markets and screened for S. aureus, and then S. aureus isolates were further examined to determine whether they were MRSA. MRSA isolates were further characterized by antimicrobial susceptibility test, pulsed-field gel electrophoresis, spa typing, multilocus sequence typing, and SCCmec typing, and were examined for genes encoding enterotoxins, exfoliative toxins, Panton-Valentine leukocidin (pvl), and toxic shock syndrome toxin 1. Among all the samples examined, four (1.4%) raw milk samples, six (2.3%) chicken samples, one (0.6%) pork sample, three (0.6%) ready-to-eat food samples, and three (2.5%) dumpling samples were positive for MRSA. No MRSA isolates were recovered from infant foods. A total of 23 MRSA isolates were recovered from the 17 MRSA-positive samples. Antimicrobial susceptibility tests showed that, among these MRSA isolates, resistance was most frequently observed to penicillin, ampicillin, oxacillin, cefoxitin, and clindamycin (each 100%), followed by erythromycin (95.7%) and clarithromycin (87.0%). The commonly detected toxin genes were pvl, seg, seb, sed, followed by see, sec, and sei. Seven spa types (t189, t377, t437, t899, t10793, t5762, and a new spa type) and three SCCmec types (II, IVb, and V) were identified. More than half (52.2%) of the MRSA isolates belonged to ST9, followed by ST88, ST59, ST188, ST72, and ST630. Our findings indicate that MRSA in food could be from both animal and human origin. Although the prevalence is low, the presence of multidrug resistant and enterotoxigenic MRSA strains in foods poses a potential threat to consumers and emphasizes the need for better control of sources of

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

    Science.gov (United States)

    Mahato, Sudipta; Mistry, Hiral U; Chakraborty, Shalini; Sharma, Paresh; Saravanan, R; Bhandari, Vasundhra

    2017-01-01

    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. xylosu s, 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 (SCC mec ) 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

  14. Staphylococci isolated from ready-to-eat meat - Identification, antibiotic resistance and toxin gene profile.

    Science.gov (United States)

    Fijałkowski, Karol; Peitler, Dorota; Karakulska, Jolanta

    2016-12-05

    The aim of this study was to analyse the staphylococci isolated from ready-to-eat meat products, including pork ham, chicken cold cuts, pork sausage, salami and pork luncheon meat, sliced in the store to the consumer's specifications, along with species identification and determination of antibiotic resistance. Genes encoding staphylococcal enterotoxins, staphylococcal enterotoxin-like proteins, exfoliative toxins, and toxic shock syndrome toxin 1 were also investigated. From the 41 samples, 75 different staphylococcal isolates were obtained. Based on PCR-RFLP analysis of the gap gene using AluI and HpyCH4V restriction enzymes, the isolates were identified as Staphylococcus equorum (28%), S. vitulinus (16%), S. carnosus (14%), S. succinus (11%), S. xylosus (11%), S. saprophyticus (9%), S. warneri (9%), S. haemolyticus (1%) and S. pasteuri (1%). The incidence and number of resistances to antimicrobials was found to be species but not source of isolation dependent. All S. xylosus, S. saprophyticus, S. haemolyticus and S. pasteuri isolates showed antibiotic resistance. A lower percentage of resistance was recorded for S. warneri (71%) and S. vitulinus (58%), followed by S. equorum (57%), S. carnosus (50%) and S. succinus (50%). The most frequent resistance was observed to fusidic acid (43%). The mecA gene was amplified in 4% of the staphylococci. However, phenotypic resistance to methicillin was not confirmed in any of these isolates. On the other hand, the mecA gene was not detected in any of 9% of the isolates resistant to cefoxitin. It was also found that among 75 isolates, 60 (80%) harbored from 1 to 10 out of 21 analyzed superantigenic toxin genes. The most prevalent genes were: sei (36% isolates) among enterotoxins, seln (32% isolates) among enterotoxin-like proteins and eta encoding exfoliative toxin A (37% isolates). The findings of this study further extend previous observations that, when present in food, not only S. aureus but also other species of

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

    Science.gov (United States)

    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

  16. Epidemiological study of pathogens collected from blood for a period of a year (2008-2009

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    Eugenio A. Debbia

    2009-09-01

    Full Text Available Objectives. An epidemiological study, addressed to identify the pathogens isolated from blood, and their antibiotic susceptibility patterns, was conducted. Methods. 12 laboratories, homogeneously distributed in a Northern area of Italy, were required to collected all consecutive non-duplicated strains isolated from blood during February 2008 to February 2009 and sent them to the reference laboratory. Results. A total of 1092 microorganisms were collected, including 653 gram-positive, 385 gram-negative and 54 fungi. Escherichia coli 234, Staphylococcus epidermidis 205, S. aureus 142, S. hominis 87, Enterococcus faecalis 47, S. haemolyticus 33, Klebsiella pneumoniae 33, Pseudomonas aeruginosa 32, Candida albicans 28, Enterobacter cloacae 21 were the prevalent microrganisms found. Samples were collected mainly from medicine (255 strains, intensive care units (154, surgery (99, infectious diseases (93, paediatrics (62 and nephrology (62. Antibiotic resistance (in % in staphylococci was 65.7 (methicillin, 33.5 (gentamicin, 61.8 (azithromycin, 59.6 (erythromycin, 45.2 (ciprofloxacin 14.8 (chloramphenicol, 2.0 (teicoplanin, and 24.1 (trimethoprim-sulfamethoxazole no vancomycin-resistant strain was found. Enterococci showed resistance to vancomycin (10.8, ampicillin (34.4, gentamycin (42.9, ciprofloxacin (42.2 teicoplanin (7.6, erythromycin (54.7 and chloramphenicol (17.5. Enterobacteriaceae exhibited resistance to ciprofloxacin(27.0, ampicillin (74.1, ceftazidime (15.8, cefoxitin (14.7, cefepime (13.3, ceftriaxone (15.0, both imipenem and amikacin (0.95, piperacillin-tazobactam (5.1 and trimethoprim-sulfamethoxazole (32.7. Non fermenting gram negative strains were found resistant to ciprofloxacin (27.3, ceftazidime (9.5, cefepime (14.6, ceftriaxone (81.6, both imipenem and amikacin (18.6, trimethoprim-sulfamethoxazole (65.2, and piperacillin-tazobactam (7.5. Conclusions.These data show a prevalent incidence of gram-positive (59.7 % in comparison to

  17. Comparison of Mec A Gene in Staphylococcus Aureus Isolated from Children at Time of Admission and Discharge in West of Iran

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    Keyghobad Ghadiri

    2016-05-01

    Full Text Available Staphylococcus aureus (SA is a species of the genus Staphylococcus that is found everywhere, including in the respiratory tract and on the skin of many adults and children, and that is considered one of the main pathogens in nosocomial and community acquired infections. The number of Methicillin-Resistant Staphylococcus aureus (MRSA strains has increased globally over the past two decades. Determining the frequency of mecA gene in SA that represent MRSA in hospitalized children and comparing it upon hospital admission and discharge therefore appear essential. The present cross sectional study was conducted in children hospitalized in Imam Reza hospital in Kermanshah, Iran in 2012. Nasal specimens were collected from the 500 children at time of admission, considered as community acquired Staph aureus and those whose first nasal culture was negative were included for second culture at time of discharge, considered as hospital acquired Staph aureus. After identifying Staphylococcus aureus by common laboratory tests, methicillin resistance was determined using Oxacillin screening plates and mec -A gene. The prevalence of community acquired Staph aureus nasal carriers was estimated as 4.6% and the prevalence of its hospital-acquired type as 5.6%. The prevalence of mecA gene was 17/4% and 37% in two groups, suggesting no statistically significant differences between the two groups. The resistance to Erythromycin, Cefoxitin, Mupirocin and Clindamycin was 30/4%, 8/7%, 4/3% and 30/4% in the admission group and 40/70%, 7/4%, 7/4% and 18/5% in the discharge group, suggesting no statistically significant differences between the two groups. All the samples were sensitive to Vancomycin and Linezolid and no instances of resistance to these antibiotics were observed. The increase in the prevalence of MRSA is caused by the overuse of antibiotics, which facilitates the colonization of MRSA. Moreover, the increase in the resistance to commonly-used antibiotics is

  18. Microbiological and molecular characterization of Staphylococcus hominis isolates from blood.

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    Soraya Mendoza-Olazarán

    Full Text Available BACKGROUND: Among Coagulase-Negative Staphylococci (CoNS, Staphylococcus hominis represents the third most common organism recoverable from the blood of immunocompromised patients. The aim of this study was to characterize biofilm formation, antibiotic resistance, define the SCCmec (Staphylococcal Chromosomal Cassette mec type, and genetic relatedness of clinical S. hominis isolates. METHODOLOGY: S. hominis blood isolates (n = 21 were screened for biofilm formation using crystal violet staining. Methicillin resistance was evaluated using the cefoxitin disk test and the mecA gene was detected by PCR. Antibiotic resistance was determined by the broth microdilution method. Genetic relatedness was determined by pulsed-field gel electrophoresis (PFGE and SCCmec typed by multiplex PCR using two different methodologies described for Staphylococcus aureus. RESULTS: Of the S. hominis isolates screened, 47.6% (10/21 were categorized as strong biofilm producers and 23.8% (5/21 as weak producers. Furthermore, 81% (17/21 of the isolates were methicillin resistant and mecA gene carriers. Resistance to ampicillin, erythromycin, and trimethoprim was observed in >70% of isolates screened. Each isolate showed a different PFGE macrorestriction pattern with similarity ranging between 0-95%. Among mecA-positive isolates, 14 (82% harbored a non-typeable SCCmec type: eight isolates were not positive for any ccr complex; four contained the mec complex A ccrAB1 and ccrC, one isolate contained mec complex A, ccrAB4 and ccrC, and one isolate contained the mec complex A, ccrAB1, ccrAB4, and ccrC. Two isolates harbored the association: mec complex A and ccrAB1. Only one strain was typeable as SCCmec III. CONCLUSIONS: The S. hominis isolates analyzed were variable biofilm producers had a high prevalence of methicillin resistance and resistance to other antibiotics, and high genetic diversity. The results of this study strongly suggested that S. hominis isolates harbor

  19. The Study of Pantone Valentin Leukocidin (PVL Gene in Methicillin-resistant Staphylococcus Aureus Isolated from Blood and Wound in Zahedan, Iran

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    H Tahmasebi

    2016-09-01

    Full Text Available Background & aim: Panton-Valentine leukocidin (PVL is a Staphylococcus aureus gamma toxin. There may be a link between Meticillin-Resistant Staphylococcus aureus and Panton-Valentine leukocidin (PVL, as an important cytotoxin found particularly in severe infections. The purpose of this study was to isolate and identify Staphylococcus aureus virulence Panton-Valentine leukocidin (PVL and methicillin resistance genes in clinical samples using PCR techniques. Methods: In the present cross-sectional study, 89 isolates were collected from blood samples and detected as Staphylococcus aureus during the period of 6 months at Ali Ebne AbiTaleb Hospital, Zahedan, Iran. Initially, the case study examples were examined by biochemical tests. Then, based on recognized standards, Staphylococcus aureus isolates were isolated. Afterwards, isolates obtained were confirm by using 16srRNA gene. Subsequently, the antibiotic susceptibility of all isolates to methicillin was determined using Cefoxitin(30µg disk diffusion and agar screening methods. Finally, the PCR method was used to determine PVL and mecA genes. All results were analyzed by the Chi-square test. Results: Out of the total 89 isolates of Staphylococcus aureus blood isolates, 26 isolates from wounds and 63 were isolated. Most samples were obtained from female patients. According to the molecular analysis, 47 isolates (82/52% were mecA gene and resistant to methicillin and 42 strains (47/2% was methicillin-sensitive. Resistance to vancomycin wasn’t observed in isolates. Erythromycin and Penicillin had the highest prevalence of antibiotic resistance among isolates, respectively. Multi-resistant strains were the most PLV genes frequent. A significant relationship was observed between the resistance and the presence of Pantone Valentin (P≥0 / 05. Conclusions: Due to the frequency of mecA and PLV genes in resistant and susceptible strains of Staphylococcus aureus, and also the distribution of Pantone

  20. Phenotype, genotype, and antibiotic susceptibility of Swedish and Thai oral isolates of Staphylococcus aureus

    Science.gov (United States)

    Blomqvist, Susanne; Leonhardt, Åsa; Arirachakaran, Pratanporn; Carlen, Anette; Dahlén, Gunnar

    2015-01-01

    Objective The present study investigated phenotypes, virulence genotypes, and antibiotic susceptibility of oral Staphylococcus aureus strains in order to get more information on whether oral infections with this bacterium are associated with certain subtypes or related to an over-growth of the S. aureus variants normally found in the oral cavity of healthy carriers. Materials and methods A total number of 157 S. aureus strains were investigated. Sixty-two strains were isolated from Swedish adults with oral infections, 25 strains were from saliva of healthy Swedish dental students, and 45 strains were from tongue scrapings of HIV-positive subjects in Thailand, and 25 Thai strains from non-HIV controls. The isolates were tested for coagulase, nitrate, arginine, and hemolysin, and for the presence of the virulence genes: hlg, clfA, can, sdrC, sdrD, sdrE, map/eap (adhesins) and sea, seb, sec, tst, eta, etb, pvl (toxins). MIC90 and MIC50 were determined by E-test against penicillin V, oxacillin, amoxicillin, clindamycin, vancomycin, fusidic acid, and cefoxitin. Results While the hemolytic phenotype was significantly (p<0.001) more common among the Thai strains compared to Swedish strains, the virulence genes were found in a similar frequency in the S. aureus strains isolated from all four subject groups. The Panton-Valentine leukocidin (PVL) genotype was found in 73–100% of the strains. More than 10% of the strains from Swedish oral infections and from Thai HIV-positives showed low antibiotic susceptibility, most commonly for clindamycin. Only three methicillin-resistant S. aureus (MRSA) strains were identified, two from oral infections and one from a Thai HIV patient. Conclusions S. aureus is occasionally occurring in the oral cavity in both health and disease in Sweden and Thailand. It is therefore most likely that S. aureus in opportunistic oral infections originate from the oral microbiota. S. aureus should be considered in case of oral infections and complaints

  1. Assessment of Staphylococcus aureus along milk value chain and its public health importance in Sebeta, central Oromia, Ethiopia.

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    Ayele, Yodit; Gutema, Fanta Desissa; Edao, Bedaso Mamo; Girma, Robel; Tufa, Takele Beyene; Beyene, Tariku Jibat; Tadesse, Fanos; Geloye, Mesula; Beyi, Ashenafi Feyisa

    2017-06-27

    Staphylococcus aureus is one of the leading causes of gastroenteritis acquired from contaminated foods such as milk and milk products. However, such information is limited in Ethiopia. A cross-sectional study was conducted to assess the contamination of milk with S. aureus and knowledge, attitudes and practices (KAP) of actors along the milk value chain in Sebeta, Central Oromia, Ethiopia. A total of 291 samples collected from dairy farms, milk collection centers (MCCs) and processing plant were examined using standard microbiological techniques. The antimicrobial susceptibility profiles of the isolates were also investigated. The KAP of actors in milk value chain were evaluated through a structured questionnaire. Overall, 23.4% (n = 68) of the samples were positive for S. aureus. The prevalence of S. aureus was 19.6% (95% CI: 14.5-25.6) and 80.0% (95% CI: 14.5-25.6) at farm level and MCCs, respectively. Higher isolation rate was observed in the MCCs (p = 0.000) than the farms. The contamination rates of hands of milkers' and milking buckets with S. aureus were 32% and 11.1%, respectively. S. aureus was not isolated from pasteurized milk samples. The isolates were found to be resistant to cefoxitin (100%), penicillin G (98.5%), and streptomycin (77.9%). Among 23 interviewed farmers, 35% of them consumed raw milk, none of them wash their hands and 82.6% did not wash udder and teat before milking. Six percent of consumers had the habit of raw milk consumption. Eighty seven percent of dairy farmers and 54% of consumers had no awareness about milk borne diseases and staphylococcal food poisoning. The study revealed a high prevalence of S. aureus along the milk value chain, poor milk handling practices, raw milk consumption behavior, lack of awareness about milk borne diseases and occurrence of antimicrobials resistant S. aureus. S. aureus seems to pose a public health risk in Sebeta. Authors recommended the urgent need of public awareness creation about the

  2. Effectiveness of simple control measures on methicillin-resistant Staphylococcus aureus infection status and characteristics with susceptibility patterns in a teaching hospital in Peshawar.

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    Rafiq, Muhammad Salman; Rafiq, Muhammad Imran; Khan, Taimur; Rafiq, Maria; Khan, Mah Muneer

    2015-09-01

    To determine the effectiveness of simple control measures on the infection status and characteristics of methicillin-resistant Staphylococcus aureus including susceptibility patterns among health professionals and patients in a teaching hospital. The cross-sectional study was conducted from September 2013 to January 2014, and comprised samples collected from healthcare personnel and patients in the various units of Khyber Teaching Hospital, Peshawar. The specimens were collected before and one month after the implementation of simple control measures for outbreak prevention of methicillin-resistant Staphylococcus aureus. These were tested for culture and antimicrobial susceptibility. Data about methicillin-sensitive and methicillin-resistant Staphylococcus aureus infection, wound characteristics and susceptibility patterns was collected and effectiveness of simple control measures was determined. SPSS 20 was used for statistical analysis. Of the total 390 isolates, 180(46.2%) were Staphylococcus aureus; 77(19.7%) from healthcare personnel and 103(26.4%) from patients. Of these, 164(42.1%) were methicillin-sensitive and 16(4.1%) were methicillin-resistant. Among the patients, 38(15.1%) methicillin-sensitive and 8(3.2%) methicillin-resistant isolates were recovered from wounds or skin and soft tissues. Pus with 33(13.1%) and 4(1.6%) cases respectively was the second most common source. Among methicillin-resistant isolates, resistance to Linezolid was 0%, all were resistant to Oxacillin, Cefoxitin, Amoxicillin, Cefotaxime and Cephradine, and resistance to both Co-Amoxiclav and Ciprofloxacin was 87.5%. After one month of implementation of simple control measures, the number of methicillin-resistant cases among healthcare professionals and patients dropped from 4(2.9%) and 7(10.8%) to 1(0.7%) and 5(2.7%), respectively. Methicillin-resistant and methicillin-sensitive Staphylococcus aureus differed in their anti-microbial susceptibility profiles. Selection of antibiotics

  3. Prevalence of antibiotic resistant Staphylococcus aureus from raw milk samples collected from the local vendors in the region of Tirupathi, India

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    Sudhanthirakodi Sudhanthiramani

    2015-04-01

    Full Text Available Aim: The study was carried out with the aim to identify the suitability of the milk for consumer use with special reference to Staphylococcus aureus from milk samples collected from various local vendors and determine the antibiotic susceptibility pattern of those positive isolates. Materials and Methods: A total of 110 milk samples were collected from the local milk vendors in and around Tirupathi region of India. All the samples were enriched with buffered peptone water in 9:1 ratio and the then inoculated on baird parker agar medium with added 2% egg yolk tellurite emulsion as selective medium for S.aureus and confirmed with mannitol salt agar, Gram’s staining and biochemical tests. The typical cultural characters with coagulase-positive samples were taken as positive samples the positive samples were tested for antibiotic susceptibility with 10 different antibiotics by employing disc diffusion method. Results: Prevalence of coagulase-positive S. aureus was 39.09% (43/110 from the milk samples. The antibiotic susceptibility test of positive isolates showed high resistant toward penicillin G 37/43 (86.04% and ampicillin 32/43 (74.42%, and also showed resistant to methicillin 6/43 (13.95%, cephalothin 6/43 (13.95%, tetracycline 6/43 (13.95%, ciprofloxacin 4/43 (9.30%, enrofloxacin 3/43 (6.97%, cefoxitin 2/43 (4.65%, gentamicin 2/43 (4.65%, and co-trimoxazole 2/43 (4.65%. Many individual isolates showed resistant against two or more antibiotics in our study. Conclusion: The above study results show that the milk samples collected from local vendor having S. aureus, which can induce disease condition as well as antibiotic resistant to the humans particularly young children and old age peoples by means of consumption of raw milk and its products. This is the public health issue, which needs to be solved by educating the local vendors regarding health problems related to unhygienic milk supply and make the awareness among the consumers about this

  4. Inducible clindamycin and methicillin resistant Staphylococcus aureus in a tertiary care hospital, Kathmandu, Nepal.

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    Adhikari, R P; Shrestha, S; Barakoti, A; Amatya, R

    2017-07-11

    Staphylococcus aureus, an important nosocomial pathogen, is frequently associated with infections in human. The management of the infections by it especially methicillin resistant ones is often difficult because methicillin resistant S. aureus is usually resistant to multiple antibiotics. Macrolide-lincosamide streptogramin B family of antibiotics is commonly used to treat such infections as an alternative to vancomycin. This study was conducted over the period of one and half year from November 2013-April 2015 in Microbiology laboratory of Nepal Medical College and Teaching Hospital, Kathmandu, Nepal to find the incidence of different phenotypes of MLS B resistance among S. aureus from clinical samples and their association with methicillin resistance. Two hundred seventy isolates of S. aureus were included in the study. Methicillin resistance was detected by cefoxitin disc diffusion method and inducible clindamycin resistance by erythromycin and clindamycin disc approximation test (D-test). Of the 270 clinical isolates of S. aureus, 25.1% (68/270) were MRSA. Erythromycin and clindamycin resistance was seen in 54.4% (147/270) and 41.8% (113/270) isolates respectively. Resistance to erythromycin and clindamycin were higher in MRSA as compared to MSSA (erythromycin-resistance: 88.2% Vs 39.1% and clindamycin-resistance: 79.4% Vs 41.8%). The overall prevalence of i MLS B and c MLS B phenotype was 11.48% (31/270) and 29.25% (79/270) respectively. Both i MLS B and c MLS B phenotypes predominated in MRSA strains. Detection rate of MRSA in our study shows the necessity to improve in healthcare practices and to formulate new policy for the control of MRSA infections. Clindamycin resistance in the form of i MLS B and c MLS B especially among MRSA emphasizes the need of D-test to be performed routinely in our set up while using clindamycin as an alternative choice to anti-staphylococcal antibiotics like vancomycin and linezolid in the treatment of staphylococcal infections.

  5. Community-acquired methicillin-resistant Staphylococcus aureus from skin and soft tissue infections (in a sample of Egyptian population: analysis of mec gene and staphylococcal cassette chromosome

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    Nagat Sobhy

    Full Text Available BACKGROUND: Staphylococcus aureus has been recognized as an important pathogen associated with inpatients and community infections. Community-acquired methicillin-resistant S. aureus (CA-MRSA infections commonly present as skin and soft-tissue infections (SSTIs. Treatment often includes incision and drainage with or without adjunctive antibiotics. OBJECTIVES: This study aimed to identify CA-MRSA infections both phenotypically and genotypically, to determine their spectrum of antibiotic resistance, and to establish the best scheme for molecular distinction between hospital-acquired MRSA (HA-MRSA and CA-MRSA by staphylococcal cassette chromosome mec (SCCmec typing and detection of Panton Valentine leukocidin (PVL. MATERIALS: 50 swabs, from skin and soft tissue of infected lesions of outpatients attending the dermatology department of the Medical School, Alexandria University, were collected. Additionally, a nasal swab was taken from every participant. METHODS: Collection of swabs from the infected skin and soft tissues, followed by laboratory testing to phenotypically and genotypically identify MRSA. Also, nasal swabs were taken from every patient to identify MRSA colonization. RESULTS: Staphylococcus aureus strains were identified in 38 (76% of the 50 clinical isolates. 18 (47.37% out of the 38 S. aureus strains were resistant to oxacillin and cefoxitin discs, were penicillin binding protein 2a (PBP2a producers, and were initially diagnosed as MRSA. All of the 18 strains were definitively diagnosed as MRSA by mecA gene detection using real time PCR, while only six (33.33% strains were PVL positive. Using the sets of primers of Zhang et al.: nine (50% out of the 18 CA-MRSA strains were SCCmec type V, and one (5.56% was SCCmec type IVc. Then, using the set of primers by Oliveira et al., two (25% out of the eight untypable MRSA strains were found to be SCCmec type IV, and six (75% remained untypable. CONCLUSIONS: CA-MRSA must be considered when

  6. Clinical isolates of Escherichia coli producing TRI beta-lactamases: novel TEM-enzymes conferring resistance to beta-lactamase inhibitors.

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    Vedel, G; Belaaouaj, A; Gilly, L; Labia, R; Philippon, A; Névot, P; Paul, G

    1992-10-01

    Two different strains of Escherichia coli exhibiting unusual patterns of resistance to beta-lactam antibiotics were isolated from patients at Cochin Hospital. Both isolates showed a low level of resistance to amoxycillin, ticarcillin and ureidopenicillins but were susceptible to cephalosporins, aztreonam and imipenem; beta-lactamase inhibitors potentiated the activities of the beta-lactams to only a limited extent. All resistance characteristics of the strains were transferable by conjugation to E. coli K12. Resistance was shown to be due to beta-lactamases of pI 5.20 and relative molecular masses of 24,000. The hydrolytic and inhibition profiles of these enzymes were similar to each other but differed from those of broad-spectrum beta-lactamases (TEM-1). The rates of hydrolysis (Vmax) of amoxycillin (c. 200%) were higher than that for TEM-1 (84%). Ticarcillin, ureidopenicillins and cephaloridine were hydrolyzed slowly. However, as for TEM-1, no hydrolysis was observed with cefoxitin, third generation cephalosporins, aztreonam and imipenem. The high Km values demonstrated the poor affinity of these enzymes for their substrates. Unlike TEM-1, they were poorly inhibited by beta-lactamase inhibitors. These two enzymes differed from each other as follows: (i) the concentrations of clavulanic acid required for 50% beta-lactamase inhibition were 31 mumol/L for one enzyme (E-SAL) and 9.4 mumol/L for the other (E-GUER); (ii) p-chloromercuribenzoate was a more active inhibitor of E-SAL then E-GUER. The titration curve method and DNA-DNA hybridization studies demonstrated that both enzymes were structurally related to TEM-1. The novel plasmid-encoded enzymes produced by the two isolates of E. coli appeared to be almost identical and to be derived from TEM-enzymes. On the basis of their presumed phylogeny and their biological properties, we propose that these beta-lactamases be given the generic name TRI (TEM Resistant to beta-lactamase Inhibitors).

  7. Characterization of methicillin-resistant Staphylococcus aureus isolated from healthy turkeys and broilers using DNA microarrays

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    Hosny El-Adawy

    2016-12-01

    Full Text Available Methicillin-resistant Staphylococcus aureus (MRSA is a major human health problem and recently, domestic animals, in particular pigs and poultry are discussed as carriers and possible reservoirs of MRSA. Twenty seven S. aureus isolates from five turkey farms (n=18 and two broiler farms (n=9 were obtained by culturing of choana and skin swabs from apparently healthy birds, identified by Taqman-based real-time duplex nuc-mecA-PCR and characterized by spa typing as well as by a DNA microarray based assay which covered, amongst others, a considerable number of antibiotic resistance genes, species controls and virulence markers. The antimicrobial susceptibility profiles were tested by agar diffusion assays and genotypically confirmed by the microarray. Five different spa types (3 in turkeys and 2 in broilers were detected. The majority of MRSA isolates (24/27 belonged to clonal complex 398-MRSA-V. The most frequently occurring spa types were accordingly t011, t034 and t899. A single CC5-MRSA-III isolated from turkey and CC398-MRSA with an unidentified/truncated SCCmec element in turkey and broiler were additionally detected. The phenotypic antimicrobial resistance profiles of S. aureus isolated from both turkeys and broilers against 14 different antimicrobials showed that all isolates were resistant to ampicillin, cefoxitin, oxacillin, doxycycline and tetracycline. Moreover, all S. aureus isolated from broilers were resistant to erythromycin and azithromycin. All isolates were susceptible to gentamicin, chloramphenicol, sulphonamides and fusidic acid. The resistance rate against ciprofloxacin was 55.6% in broiler isolates and 42.1% in turkey isolates. All tetracycline resistant isolates possessed genes tetK/M. All erythromycin-resistant broiler isolates carried ermA. Only one broiler isolate (11.1% carried genes ermA, ermB and ermC, while 55.6% of turkey isolates possessed ermA and ermB genes.Neither PVL genes (lukF/S-PV, animal-associated leukocidin

  8. Risk factors associated with the A2C resistance pattern among E. coli isolates from broiler flocks in Canada.

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    Caffrey, Niamh; Nekouei, Omid; Gow, Sheryl; Agunos, Agnes; Checkley, Sylvia

    2017-12-01

    The extra-label use of ceftiofur in Canadian hatcheries was cause for concern due to an increased prevalence of ceftiofur resistant Salmonella Heidelberg in chickens and humans in Québec. Due to on-going concerns related to human health the use of ceftiofur was eventually phased out of the poultry production industry in 2014-2015. Simultaneous resistance to amoxicillin-clavulanic acid, ceftiofur and cefoxitin, a pattern known as A2C, caused by the presence of bla CMY-2 has become increasingly prevalent in broiler flocks worldwide. This study used data from the Canadian Integrated Program for Antimicrobial Resistance Surveillance (CIPARS) broiler farm surveillance program to examine the risk factors for A2C resistant Escherichia coli isolates (A2C-REI) from 1482 samples taken from 371 broiler flocks in Canada, between 2013 and 2015. Results of a mixed effects Poisson model with fixed effects at the flock level and random effects at the hatchery level indicated that the in ovo use of ceftiofur (Prevalence Ratio (PR): 1.91, 95% CI: 1.43-2.57), and the use of hydrogen peroxide to disinfect water lines during the growing period (PR: 1.52, 95% CI: 1.11-2.07), were risk factors for increased expected prevalence of A2C-REI, compared to farms not using these strategies. Controlling for wild birds (PR: 0.64, 95% CI: 0.48-0.84), use of avilamycin in feed (PR: 0.63, 95% CI: 0.41-0.98), and storage of manure on the farm (PR: 0.67, 95% CI: 0.51-0.89) were associated with a lower expected prevalence of A2C-REI, than farms that did not use these strategies. This study identified important management factors that were associated with the prevalence of A2C-REI on Canadian broiler farms. The findings of this study can be used as a baseline for the monitoring of the effects of the removal of ceftiofur from poultry production in Canada. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Prevalence and antibiotic resistance profiles of cerebrospinal fluid pathogens in children with acute bacterial meningitis in Yunnan province, China, 2012-2015.

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    Jiang, Hongchao; Su, Min; Kui, Liyue; Huang, Hailin; Qiu, Lijuan; Li, Li; Ma, Jing; Du, Tingyi; Fan, Mao; Sun, Qiangming; Liu, Xiaomei

    2017-01-01

    Acute bacterial meningitis is still considered one of the most dangerous infectious diseases in children. To investigate the prevalence and antibiotic resistance profiles of cerebrospinal fluid (CSF) pathogens in children with acute bacterial meningitis in Southwest China, CSF samples from 179 meningitis patients (3 days to 12 years old) with positive culture results were collected from 2012 to 2015. Isolated pathogens were identified using the Vitek-32 system. Gram stain results were used to guide subcultures and susceptibility testing. The antimicrobial susceptibility of isolates was determined using the disc diffusion method. Of the isolates, 50.8% were Gram-positive bacteria, and 49.2% were Gram-negative bacteria. The most prevalent pathogens were E. coli (28.5%), Streptococcus pneumoniae (17.8%), Staphylococcus epidermidis (10.0%), Haemophilus influenzae type b (9.5%), and group B streptococcus (7.2%). In young infants aged ≤3 months, E. coli was the organism most frequently isolated from CSF (39/76; 51.3%), followed by group B streptococcus (13/76; 17.1%) and Streptococcus pneumoniae (8/76; 10.5%). However, in young infants aged >3 months, the most frequently isolated organism was Streptococcus pneumoniae (24/103; 23.3%), followed by Staphylococcus epidermidis (18/103; 17.5%) and Haemophilus influenzae type b (16/103; 15.5%). Antimicrobial susceptibility tests indicated that for E. coli isolates, the susceptibility rates to aminoglycosides ranged from 56.8% to 100.0%, among them, amikacin was identified as the most effective against E. coli. As for cephalosporins, the susceptibility rates ranged from 29.4% to 78.4%, and cefoxitin was identified as the most effective cephalosporin. In addition, the susceptibility rates of piperacillin/tazobactam and imipenem against E. coli were 86.3% and 100%. Meanwhile, the susceptibility rates of Streptococcus pneumoniae isolates to penicillin G, erythromycin, chloramphenicol, ceftriaxone and tetracycline were 68.8%, 0

  10. Prevalence and antimicrobial susceptibility pattern of methicillin resistant Staphylococcus aureus isolated from clinical samples at Yekatit 12 Hospital Medical College, Addis Ababa, Ethiopia.

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    Dilnessa, Tebelay; Bitew, Adane

    2016-08-09

    Staphylococcus aureus particularly MRSA strains are one of the major causes of community and hospital acquired bacterial infections. They are also becoming increasingly multi-drug resistant and have recently developed resistance to vancomycin, which has been used successfully to treat MRSA for many years. In-vitro determination of drug resistance patterns of S. aureus is critical for the selection of effective drugs for the treatment of staphylococci infections. The main aim of this study was to determine the prevalence of methicillin resistant S. aureus strains from different clinical specimens from patients referred for routine culture and sensitivity testing. A cross sectional study was conducted among 1360 participants at Yekatit 12 Hospital Medical College in Ethiopia from September 2013 to April 2014. Clinical samples from various anatomical sites of study participants were cultured on blood agar and mannitol salt agar and identified to be S. aureus by using catalase, coagulase and DNAse tests. S. aureus isolates then were screened for MRSA using 30 μg cefoxitin disc and other 11 antimicrobial drugs by disc diffusion procedure, and agar dilution and E tests for vancomycin. All S. aureus isolates examined for beta-lactamase production by employing nitrocefin. Data were analyzed using SPSS version 20 software and logistic regressions were applied to assess any association between dependent and independent variables. Of 1360 clinical specimens analyzed S. aureus was recovered from (194, 14.3 %). Rate of isolation of S. aureus with regard to clinical specimens was the highest in pus (118, 55.4 %).No S. aureus was isolated from CSF and urethral discharge. Out of 194 S. aureus isolates, (34, 17.5 %) were found out to be MRSA and the remaining (160, 82.5 %) were MSSA. Ninety eight (50.5 %) S. aureus were multi drug resistant and the highest isolates were resistant to penicillin (187, 96.4 %) and least resistant for clindamycin (23, 11.9 %) and vancomycin

  11. MARCADORES DE PATOGENICIDADE EM Yersinia enterocolitica O: 3 ISOLADAS DE SUÍNOS DO RIO DE JANEIRO Genetic markers of pathogenicity in Yersinia enterocolitica O: 3 isolated from healthy pigs from Rio de Janeiro

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    Tereza C. A. Leal

    1997-01-01

    Full Text Available Foi realizada a caracterização genotípica e fenotípica de fatores de patogenicidade em 16 amostras de Yersinia enterocolitica O:3 isoladas de suínos sadios do Rio de Janeiro. Foi observado que apenas 6 cepas possuíam o plasmídio de virulência, pYV (+ 70 kb e apresentavam dependência ao cálcio no meio MOX a 37C. Um plasmídio críptico de cerca de 8,6 kb foi encontrado em uma cepa. Doze cepas revelaram sensibilidade à pesticina enquanto que apenas três se revelaram capazes de hidrolisar a esculina. Através de PCR com "primers" específicos, foi constatada a presença dos genes ail em 14 cepas, irp2, em 1 cepa e a ausência de psaA em todas as cepas analisadas. Quanto aos quimioterápicos, a quase totalidade das cepas mostrou-se ao mesmo tempo resistente à ampicilina e carbenicilina e sensível ao sulfazotrin e à cefoxitina. As respostas foram variadas frente ao cloranfenicol, tetraciclina, kanamicina, gentamicina e ácido nalidíxo.Sixteen Yersinia enterocolitica serotype O:3 strains, isolated from pigs from Rio de Janeiro, have been analyzed for genetic and phenotypic markers of pathogenicity. It was observed that only 6 strains harbored the pYV (+70 kb plasmid and one strain harbored a small cryptic plasmid of about 8.6 kb. Accordingly only strains harboring pYV were calcium dependent in the MOX medium at 370C. Twelve strains showed pesticin sensitivity and the esculin reaction was negative in 13 strains. PCR analysis of pathogenicity genes using specific primers showed the presence of the ail gene in 14 strains, the irp2 gene in one and the psaA in none. Most of the strains were resistant to ampicillin and carbenicillin, although they were susceptible to sulfazotrin and cefoxitin. For chloramphenicol, tetracycline, kanamycin, gentamicin and nalidixic acid the results varied among the strains.

  12. Prevalence and antimicrobial resistance of Salmonella serovars isolated from poultry in Ghana.

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    Andoh, L A; Dalsgaard, A; Obiri-Danso, K; Newman, M J; Barco, L; Olsen, J E

    2016-11-01

    Poultry are possible sources of non-typhoidal Salmonella serovars which may cause foodborne human disease. We conducted a cross-sectional study to determine the prevalence of Salmonella serovars in egg-laying hens and broilers at the farm level and their susceptibility to antimicrobials commonly used in the poultry industry in Ghana. Sampling of faeces by a sock method (n = 75), dust (n = 75), feed (n = 10) and drinking water (n = 10) was performed at 75 commercial egg-laying and broiler farms in two regions of Ghana and skin neck (n = 30) at a local slaughterhouse from broilers representing different flocks. Salmonella was detected in 94/200 (47%) samples with an overall flock prevalence of 44·0%. Sixteen different serovars were identified with S. Kentucky (18·1%), S. Nima (12·8%), S. Muenster (10·6%), S. Enteritidis (10·6%) and S. Virchow (9·6 %) the most prevalent types. The predominant phage type of S. Enteritidis was PT1. All strains were susceptible to cefotaxime, ceftazidime and cefoxitin. Fifty-seven (60·6%) strains were resistant to one or more of the remaining nine antimicrobials tested by disk diffusion, of which 23 (40·4%) showed multi-resistance (resistance to ⩾3 classes of antimicrobials). Of the resistant strains (n = 57), the most significant were to nalidixic acid (89·5%), tetracycline (80·7%), ciprofloxacin (64·9%), sulfamethazole (42·1%), trimethoprim (29·8%) and ampicillin (26·3%). All S. Kentucky strains were resistant to more than two antimicrobials and shared common resistance to nalidixic acid or ciprofloxacin and tetracycline, often in combinations with other antimicrobials. PFGE analysis using XbaI of S. Kentucky demonstrated one dominant clone in the country. In conclusion, poultry produced in Ghana has a high prevalence of multi-resistant Salmonella and the common finding of clonal S. Kentucky in the Kumasi area warrants further investigations into the epidemiology of this serovar. There is an urgent need for surveillance

  13. Evaluación del potencial probiótico de bacterias ácido lácticas para reducir el colesterol in vitro

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    Clementina Cueto

    2012-01-01

    Full Text Available El co nsumo diario de alimentos probióticos reduce los niveles de colesterol sérico en un 3%, valor significativo para la prevención de la hipercolesterolemia, factor de riesgo de enfermedad cardiovascular y causal de mortalidad. Algunas especies del género Lact obacillus , utilizadas en la industria alimentaria como probiótico, reducen el colesterol sérico por dos mecanismos, la adsorción de colesterol y producción de la enzima hidrolasa de sales biliares. El objetivo del estudio fue evaluar el potencial probiótic o de un grupo de bacterias lácticas aisladas de suero costeño. Se aislaron 53 cepas a partir de nueve muestras de suero costeño; el potencial probiótico de las bacterias se evaluó por tolerancia a pH 2.0, 0.3% de sales biliares y sensibilidad a vancomicina y cefoxitin. Se seleccionaron cinco microorganismos y se identificaron molecularmente, como Lactobacillus fermentum . La capacidad de adsorber el colesterol medida por el método de Kimoto, presentó disminución de 53.06 ± 2.69 μg.mL - 1 para la cepa K73 y 7. 23 ± 2.69 μg.mL - 1 para la cepa K75. Esas mismas cepas mostraron la mayor actividad total y específica de la enzima. Los resultados evidenciaron que no existe relación entre la producción de la enzima y la adsorción del colesterol. La cepa con mayor potenci al probiótico fue K73. La propiedad hipocolesterolémica de Lactobacillus fermentum , podría ser el inicio de la búsqueda de matrices alimentarias que permitan disminuir los niveles del colesterol sérico y adicionen valor agregado al producto.

  14. Diversity of Plasmids and Antimicrobial Resistance Genes in Multidrug-Resistant Escherichia coli Isolated from Healthy Companion Animals.

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    Jackson, C R; Davis, J A; Frye, J G; Barrett, J B; Hiott, L M

    2015-09-01

    The presence and transfer of antimicrobial resistance genes from commensal bacteria in companion animals to more pathogenic bacteria may contribute to dissemination of antimicrobial resistance. The purpose of this study was to determine antimicrobial resistance gene content and the presence of genetic elements in antimicrobial resistant Escherichia coli from healthy companion animals. In our previous study, from May to August, 2007, healthy companion animals (155 dogs and 121 cats) from three veterinary clinics in the Athens, GA, USA area were sampled and multidrug-resistant E. coli (n = 36; MDR, resistance to ≥ 2 antimicrobial classes) were obtained. Of the 25 different plasmid replicon types tested by PCR, at least one plasmid replicon type was detected in 94% (34/36) of the MDR E. coli; four isolates contained as many as five different plasmid replicons. Nine replicon types (FIA, FIB, FII, I2, A/C, U, P, I1 and HI2) were identified with FIB, FII, I2 as the most common pattern. The presence of class I integrons (intI) was detected in 61% (22/36) of the isolates with eight isolates containing aminoglycoside- and/or trimethoprim-resistance genes in the variable cassette region of intI. Microarray analysis of a subset of the MDR E. coli (n = 9) identified the presence of genes conferring resistance to aminoglycosides (aac, aad, aph and strA/B), β-lactams (ampC, cmy, tem and vim), chloramphenicol (cat), sulfonamides (sulI and sulII), tetracycline [tet(A), tet(B), tet(C), tet(D) and regulator, tetR] and trimethoprim (dfrA). Antimicrobial resistance to eight antimicrobials (ampicillin, cefoxitin, ceftiofur, amoxicillin/clavulanic acid, streptomycin, gentamicin, sulfisoxazole and trimethoprim-sulfamethoxazole) and five plasmid replicons (FIA, FIB, FII, I1 and I2) were transferred via conjugation. The presence of antimicrobial resistance genes, intI and transferable plasmid replicons indicate that E. coli from companion animals may play an important role in the

  15. The high diversity of MRSA clones detected in a university hospital in istanbul.

    Science.gov (United States)

    Oksuz, Lutfiye; Dupieux, Celine; Tristan, Anne; Bes, Michele; Etienne, Jerome; Gurler, Nezahat

    2013-01-01

    To characterize the methicillin-resistant Staphylococcus aureus (MRSA) clones present in Istanbul, 102 MRSA isolates collected during a 5-year period at the Istanbul Medical Faculty Hospital were characterized using microarray analysis and phenotypic resistance profiles. Resistance to methicillin was detected with a cefoxitin disk diffusion assay and confirmed with a MRSA-agar and MRSA detection kit. Antimicrobial susceptibility testing was performed by a disk diffusion assay and interpreted according to the 2012 guidelines of the Antibiogram Committee of the French Society for Microbiology. Decreased susceptibility to glycopeptides was confirmed using the population analysis profile-area under the curve (PAP-AUC) method. The presence of the mecA gene was detected by polymerase chain reaction. Bacterial DNA was extracted according to the manufacturer's recommended protocol using commercial extraction kits. Strains were extensively characterized using the DNA microarray. Isolates were grouped into six clonal complexes. The most frequently detected clone was the Vienna/Hungarian/Brazilian clone (ST239-MRSA-III), which accounted for 53.9% of the isolates. These isolates were resistant to multiple antibiotics, particularly penicillin, tetracycline, rifampicin, kanamycin, tobramycin, gentamicin, levofloxacin, erythromycin, lincomycin and fosfomycin. Furthermore, three isolates were detected by population analysis profile as heterogeneous vancomycin-intermediate S. aureus (hVISA). The UK-EMRSA-15 clone (ST22-MRSA-IV PVL negative) was detected in 9.8% of the isolates and was mainly susceptible to all anti-staphylococcal antibiotics. Seven isolates (6.9%) were positive for PVL genes and were assigned to the CC80-MRSA-IV clone (European CA-MRSA clone, three isolates), ST8-MRSA-IV clone (USA300 clone, two isolates, one ACME-positive) or ST22-MRSA-IV clone ("Regensburg EMRSA" clone, two isolates). All other clones were detected in one to six isolates and corresponded to well

  16. Microbiological and biochemical studies on certain antibiotic-resistant bacteria isolated from certain clinical specimens

    International Nuclear Information System (INIS)

    Nada, H.M.AL.M.

    2008-01-01

    . Determination of B-lactamase and AmpC-B-lactamase enzyme production were carried out by two methods. Cefotaxime, ceftazidime, cefoperazone, cefoxitin and aztreonam were used with and without amoxycillin clavulanic acid to detect the presence of extended-spectrum B-lactamase (ESBL) harbouring isolates by using double-disk diffusion synergy test (DDST). Combined disk method was used also to detect the presence of ESBL harbouring isolates by using cefoperazone (CFP) and cefoperazone sulbactam (SCF) among the tested strains. Agar dilution method was used to determine minimum inhibitory concentration (MIC) of ampicillin sulbactam, cefoperazone, gentamycin and levofloxacin alone and in combination (Ampicillin sulbactam with both of gentamycin and levofloxacin) and (cefoperazone with both of gentamycin and levofloxacin). Fractional inhibitory concentration (FIC) for the combined antibiotics were calculated according to checkerboard method and synergistic effect were determined. Some resistant isolates were subjected to molecular studies including plasmid profile (Kleb.52 Morg.60 and Ps.72 ) by using a high pure plasmid isolation kit and protein pattern of Ps.72 before and after irradiation in the presence of different antibiotics alone (cefoperazone, gentamycin and ampicillin sulbactam) or in combined (cefoperazone with gentamycin and ampicillin sulbactam with gentamycin)The result of the present investigation showed that, 9 multi-drug resistant isolates were identified as; 2 isolates Escherichia coli, 2 isolates Pseudomonas aeruginosa, 1 isolate Citrobacter freundii, 1 isolate Morganella morganii all were isolated from urine samples

  17. Antimicrobial resistance profile of Staphylococcus aureus isolates obtained from skin and soft tissue infections of outpatients from a university hospital in Recife -PE, Brazil Perfil de resistência antimicrobiana de isolados de Staphylococcus aureus provenientes de infecções de pele e tecidos moles de pacientes ambulatoriais de um hospital universitário em Recife - PE, Brasil

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    Fabiana Beserra Caraciolo

    2012-12-01

    Full Text Available BACKGROUND: Staphylococcus aureus has a notable ability to acquire resistance to antibiotics, and methicillin resistance represents a growing public health problem. Methicillin-resistant S. aureus (MRSA has also become important outside the hospital environment, particularly in the United States. In Brazil, since 2005, cases of community skin infections caused by MRSA have been reported, but resistance studies involving outpatients are scarce. OBJECTIVE: To know the resistance profile of S. aureus involved in skin and soft tissue infections of patients seen at the Dermatology outpatient clinic of a university hospital in Recife, Pernambuco State, northeastern Brazil. METHODS: Prospective study involving 30 patients with skin and soft tissue infections, seen at the Dermatology outpatient clinic from May until November 2011. To evaluate the susceptibility of S. aureus to antibiotics, the disk diffusion method and oxacillin screening agar were used. RESULTS: From a total of 30 samples of skin lesions, 19 (63% had positive culture for S. aureus. The following resistance patterns of S. aureus were observed: penicillin, 95%; tetracycline, 32%; erythromycin, 21%; gentamicin, 16%; cefoxitin, 11%; oxacillin, 11%; trimethoprim-sulfamethoxazole, 11%; chloramphenicol, 11%; clindamycin, 5% ; and ciprofloxacin, 0%. One of the identified MRSA was obtained from a patient without risk factors for its acquisition, and was resistant, beyond to the beta-lactams, only to tetracycline. CONCLUSIONS: With regard to the resistance patterns of S. aureus, resistances to tetracycline, erythromycin and gentamicin were the highest. It was documented, for the first time in Pernambuco, a case of skin infection caused by community-associated MRSA.FUNDAMENTOS: O Staphylococcus aureus possui uma notável habilidade de adquirir resistência antimicrobiana, sendo a resistência à meticilina um problema de saúde pública crescente. O S. aureus resistente à meticilina (MRSA vem se

  18. Detecção de Listeria, Salmonella e Klebsiella em serviço de alimentação hospitalar Detection of Listeria, Salmonella and Klebsiella in a hospital food service

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    Uelinton Manoel Pinto

    2004-09-01

    equipment used for food preparation in a hospital food service, and four samples collected from enteral diets were tested for bacteria of genera Listeria, Salmonella and Klebsiella. Typical colonies of bacteria of the genus Listeria from enteral diet were isolated in Oxford agar and contamination by L. monocytogenes was confirmed by immunoanalysis. RESULTS: L. monocytogenes, S. rissen and Klebsiella were isolated from enteral diet. For their relevance as agents of hospital infections, bacteria of the genus Klebsiella were evaluated. K. pneumoniae were found in equipment and utensil, and K. oxytoca were found in environment, equipment and enteral diet samples. L. monocytogenes showed resistance to cefoxitin and all Klebsiella were resistant to amoxacillin and ampicillin. S. rissen showed susceptibility to all 13 antibiotics tested. CONCLUSION: The study showed that 11% of the analyzed samples were contaminated with, at least, one of the investigated pathogens. Such results reiterate the need for awareness and knowledge of effective hygienic procedures in the hospital food manipulation areas, in order to ensure patients' safety.

  19. Characterization of extended-spectrum β-lactamases (ESBLs)-producing Salmonella in retail raw chicken carcasses.

    Science.gov (United States)

    Qiao, Jing; Zhang, Qiang; Alali, Walid Q; Wang, Jiawei; Meng, Lingyuan; Xiao, Yingping; Yang, Hua; Chen, Sheng; Cui, Shenghui; Yang, Baowei

    2017-05-02

    Extended-spectrum β-lactamases (ESBLs)-producing Salmonella is considered a serious concern to public health worldwide. However, limited information is available on ESBLs-producing Salmonella in retail chicken products in China. The objective of this study was to characterize ESBLs-producing Salmonella isolates from retail chickens in China. A total of 890 Salmonella isolates from retail chicken carcasses collected from 4 provinces were firstly screened for ESBLs-production phenotype via the double-disk synergy test method. A total of 96 (10.8%, n=890) ESBLs-producing Salmonella were identified and subjected to PFGE analysis, characterization for the presence of ESBLs encoding genes, transposons, carbapenemase and virulence genes. A total of 59 PFGE profiles were detected in these 96 isolates, among which 57.3% were found to harbor bla TEM-1 , whereas 30.2%, 24.0%, 18.8% and 7.3% were carrying bla OXA-1 , bla CTX-M-15 , bla CTX-M-3 and bla PSE-1 genes, respectively. Moreover, 42 (43.8%) isolates co-carried 2 ESBLs-producing genes, and two (2.1%) isolates co-carried 3 genes. Furthermore, 24 (25.0%) ESBLs-producing isolates carried VIM and 10 (10.4%) carried KPC encoding genes that closely associated with carbapenems resistance. Eighty-eight isolates harbored transposons ranging from 4.2% for Tn903 to 76.0% for Tn21. Out of the 88 Salmonella that harbored transposons, 25%, 22.7%, 23.9%, 10.2% and 1.1% of isolates were found to carry 2, 3, 4, 5 and 6 transposons, respectively. The minimum inhibitory concentration (MIC) values for cephalosporins (ceftriaxone, cefoperazone and cefoxitin) to ESBLs-producing isolates were from 4 to 1024μg/mL, for nalidixic acid were from 64 to 512μg/mL, for fluoroquinolones (ciprofloxacin, levofloxacin and gatifloxacin) were from 4 to 256μg/mL. Twenty-nine virulence genes were detected in the 96 ESBLs-producing isolates with 2.1% harbored spvR (lowest) and 90.6% harbored marT and steB (highest). All isolates carried at least one

  20. Bacteriologic Profile and Antibiogram of Blood Culture Isolates from a Children's Hospital in Kabul

    International Nuclear Information System (INIS)

    Tariq, O. M.

    2014-01-01

    Objective: To identify the bacterial pathogens causing paediatric septicaemia in Kabul and to determine their antibiogram to improve empirical antibiotic therapy. Study Design: Cross-sectional study. Place and Duration of Study: Microbiology Laboratory of FMIC, Kabul, Afghanistan, from January 2010 to June 2012. Methodology: Blood cultures from suspected cases of sepsis were processed in BD (Becton Dickinson, USA) for culture BACTEC 9240 Blood Culture System. Positive growths were examined and isolates were identified by conventional biochemical tests. Bacteria were identified to the species level using various Analytical Profile Index (API) identification strips. Antibiotic susceptibility testing was performed by modified Kirby-Bauer disk diffusion method. Drug resistant strains were studied for extended spectrum beta lactamase (ESBL) production by combination disk method and for methicillin resistant Staphylococcus aureus (MRSA) by Cefoxitin disk diffusion method. Results: Out of a total 3360 blood cultures received from in-patients, 410 yielded monomicrobial growth; hence the frequency of positive blood culture was 12.2%. Out of a total 410 isolates, 212 (51.71%) were gram-negative bacilli and 184 (44.88%) were gram-positive cocci. In addition, 14 (3.41%) Candida species were also isolated. The frequently isolated species of gram-negative bacteria belonged to Enterobacteriaceae and included 66 Klebsiella (16.1%), 42 Enterobacter (10.2%), 35 Escherichia (E.) coli (8.5%) and 16 Serratia (3.9%) species. In addition, 21 (5.12%) Pseudomonas species were also isolated. Correspondingly, amongst gram-positive cocci, the most frequently isolated species were 108 coagulase-negative Staphylococci (26.34%) followed by 49 Staphylococcus aureus (11.95%) and 21 Streptococcus species (5.12%). Among gram-negative isolates, those that produced ESBL i.e., 110 out of 212 (51.9%) were found to be multidrug-resistant and showed high resistance to commonly used antibiotics namely

  1. Caracterização de Staphylococcus aureus isolados da barra de mão de carrinhos e alças de cestas de supermercados

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    Daiane Buzzatto Oliveira

    2016-07-01

    supermarkets from the city of Campo Mourão – PR, and characterize the susceptibility of isolates to oxacillin. One hundred twenty samples, of which 60 collected from bars hand stands and collected 60 of the handles of baskets. This micro-organism was isolated in 75 samples (62.5%, and of this total, 35 samples (46,7% were isolated from carts and 40 (53,3% of shopping baskets. The positive samples for Staphylococcus aureus were submitted to susceptibility testing by the disk diffusion method to oxacillin (cefoxitin and all samples were found to be sensitive to this drug. It found that the bars of hands and the handles of supermarket baskets can be considered as fomites in the dissemination of Staphylococcus aureus, being extremely important to sanitization these objects in order to reduce the risk of contamination in the community.Keywords: Surfaces. Contamination. Staphylococcus aureus. Oxacillin.

  2. [Detection of Staphylococcus aureus resistant to methicillin (MRSA) by molecular biology (Cepheid GeneXpert IL, GeneOhm BD, Roche LightCycler, Hyplex Evigene I2A) versus screening by culture: Economic and practical strategy for the laboratory].

    Science.gov (United States)

    Laudat, P; Demondion, E; Jouannet, C; Charron, J; Chillou, C; Salaun, V; Mankikian, B

    2012-06-01

    Patients admitted in cardiac surgery and cardiac ICU at the Clinic Saint-Gatien (Tours) are screened for MRSA at the entrance by nasal swab and culture on blood agar and selective chromogenic medium made by addition of cefoxitin: BBL CHROMagar MRSA-II BD (result obtained at Day +1). We wanted to assess the molecular biology techniques available to obtain a result at day 0 for the majority of patients and to define an economic and practical strategy for the laboratory. We studied four molecular biology techniques: Cepheid GeneXpert (Cepheid) GeneOhm (BD), LightCycler (Roche) and Hyplex (I2A). Upon reception, nasal swabs were treated by culture, considered as reference, and one of the techniques of molecular biology, according to the manufacturer's notice. We conducted four studies between April 2008 and February 2009 to obtain a significant sample for each of them. By screening we mean a method that allows us to exclude MRSA carriage for patients waiting for surgery, and not to change patient management: for example, lack of isolation measures specific to entrance, no modification of antibiotic prophylaxis during surgery and no isolation measures in the immediate postoperative period. The criteria we considered for this evaluation were: (1) technician time: time to perform one or a series of sample(s) n=10 or more (about 2h for all techniques except GeneXpert 75min), level of skilled competences (no specific training for GeneXpert); (2) results: turnaround time (all molecular biology techniques), ease of reading and results interpretations (no specialized training required for GeneXpert), failure or not (12% of failure of internal controls for GeneOhm); (3) economic: cost for one or a series of sample(s) (n=10 or more), if we considered X as the reference culture cost (10 X Hyplex and LightCycler, 20 X and 40 X for GeneXpert GeneOhm); (4) NPV: 100% for GeneXpert and LightCycler. At same sensitivity, no technique, including culture, can solve alone our problem, which

  3. Environmental "Omics" of International Space Station: Insights, Significance, and Consequences

    Science.gov (United States)

    Venkateswaran, Kasthuri

    2016-07-01

    detected. The nine-erythromycin sensitive S. aureus strains exhibited spontaneous mutation when rifampin was tested. Some of the S. aureus strains tolerated gentamycin and tobramycin but cefazolin, cefoxitin, ciprofloxacin and oxacillin inhibited the growth of the S. aureus. Whole genome sequencing (WGS) of 21 ISS strains, exhibiting resistance to various antibiotics, was carried out. The antibiotic resistant genes deduced from the WGS were compared with the resistomes generated directly from the gene pool of the environmental samples. Using a targeted amplification panel consisting of over 500 antimicrobial resistance genes, we were able to confirm the results of the phenotypic assays. Specifically, the presence of multiple β-lactamase genes was observed. The class A β-lactamase genes, tem-1 (ampicillin-resistance) and ctx-M-14 (cefotaxime conferring gene), were found in multiple sites of ISS. In addition, presence of mecA gene (penicillin clusters) was confirmed in several sampling locations from both ISS flights. Finally, the existence of the ermA gene (erythromycin) was established. These results suggest widespread and consistent distribution of multiple antibiotic resistance genes throughout the ISS. The resistome data generated via molecular methods will be extremely important in determining the microbial significance to the crew health and the ISS maintenance. These data sets will be placed in the NASA GeneLab bioinformatics environment - consisting of a database, computational tools, and improved methods - that would subsequently be made open to the scientific research community to encourage innovation.

  4. Detection, seroprevalence and antimicrobial resistance of Yersinia enterocolitica and Yersinia pseudotuberculosis in pig tonsils in Northern Italy.

    Science.gov (United States)

    Bonardi, S; Bruini, I; D'Incau, M; Van Damme, I; Carniel, E; Brémont, S; Cavallini, P; Tagliabue, S; Brindani, F

    2016-10-17

    Yersiniosis is the third most common reported zoonoses in Europe, with Y. enterocolitica and Y. pseudotuberculosis responsible for 98.66% and 0.94% of the confirmed human cases in 2013. From June 2013 to October 2014, 201 pigs at slaughter belonging to 67 batches were tested for Y. enterocolitica and Y. pseudotuberculosis in tonsils. Diaphragm muscle samples were tested for antibodies against Yersinia by a commercially available ELISA test. Y. enterocolitica 4/O:3 was detected in 55/201 pig tonsils (27.4%; 95% CI 23.1-37.1). The positive pigs came from 38/67 batches (56.7%) and were reared in 36/61 farms (59.0%). There was no statistical difference between farrow-to-finish and finishing farms. The mean count of Y. enterocolitica was 3.56±0.85log10CFU/g with a minimum of 2.0log10CFU/g and a maximum of 4.78log10CFU/g. Y. pseudotuberculosis was isolated from 4/201 pig tonsils (2.0%; 95% CI 0.0-4.5). Three isolates belonged to serotype O:3 and one to serotype O:1. The positive pigs belonged to 4/67 batches (6.0%) and came from finishing farms only. Y. pseudotuberculosis could be enumerated in one sample only (4.27log10CFU/g). The ELISA test demonstrated that 56.1% of the meat juice samples were positive for Yersinia antibodies. Serological positivity was found in 67.9% (36/53) of the Y. enterocolitica- and 75.0% (3/4) of the Y. pseudotuberculosis positive pigs. A significant association was found between serological results and the presence of Y. enterocolitica in tonsils (OR=1.97, p=0.044). All the Y. enterocolitica 4/O:3 isolates were susceptible to amoxicillin-clavulanic acid, gentamicin, ceftazidime, ertapenem and meropenem, 94.5% to cefotaxime, 89.1% to kanamycin and 78.2% to tetracycline. The highest resistance rates were observed for ampicillin (100%), sulphonamides (98.2%) and streptomycin (78.2%). Y. pseudotuberculosis strains were sensitive to all the antimicrobials tested, i.e. amoxicillin, amoxicillin/clavulanic acid, azithromycin, cephalothin, cefoxitin

  5. Randomized clinical trial comparing spinal anesthesia with local anesthesia with sedation for loop colostomy closure Ensaio clínico randomizado comparando raquianestesia com anestesia local, associadas à sedação para o fechamento de colostomia em alça

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    Rone Antônio Alves de Abreu

    2010-09-01

    Full Text Available CONTEXT: Recent studies have shown that local anesthesia for loop colostomy closure is as safe as spinal anesthesia for this procedure. OBJECTIVES: Randomized clinical trial to compare the results from these two techniques. METHODS: Fifty patients were randomized for loop colostomy closure using spinal anesthesia (n = 25 and using local anesthesia (n = 25. Preoperatively, the bowel was evaluated by means of colonoscopy, and bowel preparation was performed with 10% oral mannitol solution and physiological saline solution for lavage through the distal colostomy orifice. All patients were given prophylactic antibiotics (cefoxitin. Pain, analgesia, reestablishment of peristaltism or peristalsis, diet reintroduction, length of hospitalization and rehospitalization were analyzed postoperatively. RESULTS: Surgery duration and local complications were greater in the spinal anesthesia group. Conversion to general anesthesia occurred only with spinal anesthesia. There was no difference in intraoperative pain between the groups, but postoperative pain, reestablishment of peristaltism or peristalsis, diet reintroduction and length of hospitalization were lower with local anesthesia. CONCLUSIONS: Local anesthesia plus sedation offers a safer and more effective method than spinal anesthesia for loop colostomy closure.CONTEXTO: Estudos recentes têm demonstrado que a anestesia local para o fechamento de colostomia em alça é tão segura quanto a raquianestesia para estes procedimentos. OBJETIVOS: Comparar os resultados do fechamento de colostomia em alça usando essas duas técnicas. MÉTODOS: Cinquenta pacientes foram randomizados para o fechamento de colostomia em alça sob raquianestesia (n = 25 e anestesia local (n = 25. No pré-operatório, o cólon foi avaliado por colonoscopia e o preparo intestinal foi realizado com solução oral de manitol a 10% e limpeza com solução salina fisiológica através do orifício distal da colostomia. Todos os

  6. Staphylococcus aureus: incidência e resistência antimicrobiana em abscessos cutâneos de origem comunitária Staphylococcus aureus: etiology and susceptibility profile to antimicrobial agents of skin and subcutaneous cell tissue abscesses from community infections

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    Martin Zavadinack Netto

    2002-03-01

    profilaxia ou tratamento de infecções por S.aureus, mesmo aqueles de origem comunitária.An analysis of Staphylococcus aureus (Monera, an etiological agent of community infections, is provided. Staphylococcus aureus causes the formation of skin and subcutaneous cell tissue abscesses. Susceptibility profile to antimicrobials used in prophylaxis or therapy of these cutaneous infections will be given. One hundred and seven samples of secretions were collected from January 1996 through July 1997 at the emergency sector of University Hospital of the State University of Maringá, Maringá, state of Paraná, Brazil, from infected patients with skin and subcutaneous cell tissue abscesses. Microbiological evaluation was carried out according to Bayle and susceptibility to antimicrobial was evaluated in vitro through the technique of diffusion in agar according to Kirby. Sixteen antimicrobials used in prophylaxis or therapy of skin and subcutaneous cell tissue infections were evaluated. From the one hundred and seven clinical samples collected from patients complaining of infections with skin and subcutaneous cell tissue abscesses, 71 (66.35% were positive to S.aureus and 36 (33,65% were either positive for other microorganisms, or tested negative. In the evaluation of susceptibility to S.aureus a higher sensitivity to vancomycin (100%, teicoplanin (100%, amikacin (100%, cefoxitin (100%, cephalothin (98.53%, lincomycin (98.53%, gentamicin (98.53%, oxacillin (96,4%, norfloxacin (95.77% and sulfazotrin (95.77% was found when compared to penicillin G (08.45%, ampicillin (08.45%, kanamycin (81,69%, erythromycin (88.41%, tetracycline (90.14 and chloramphenicol (94,36%. Results show that S.aureus is the most frequently isolated microorganism from community infections with skin and subcutaneous tissue abscesses. The susceptibility profile evidences high resistance to penicillins, which restricts the use of these antimicrobials as an alternative in the prophylaxis or treatment of S

  7. Etiologia e perfil de sensibilidade de bactérias isoladas de ovelhas com mastite na região nordeste do estado do Pará Etiology and antimicrobial susceptibilities of bacteria isolated from sheep with mastitis in northeastern Pará, Brazil

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    Natália da Silva e Silva

    2010-12-01

    isolated were Staphylococcus spp. coagulase negative (26.9%; Staphylococcus aureus (15.,4%; Streptococcus spp. (7.69%; Escherichia coli (7.69% and Citrobacter freundii (11.5%. Were observed associations of Staphylococcus spp. coagulase negative nonhemolytic and Staphylococcus spp. coagulase negative hemolytic (3.85%. The most efficient antibiotics for the Gram positive agents were penicile/novobiocine (100%, cefalotine (100% and florfenicol (100% and for the Citrobacter freundii were ampicilina (100% and florfenicol (100%. In relation to Escherichia coli, 66.7% of isolates to ampicillin, cephalothin, florfenicol and tetracycline were resistant. Mastitis is present in sheep in the State of Pará, and it's necessary to estimate, in future studies, the economic losses caused by this disease. The CMT show satisfactory results and can be recommended as a screening test for diagnosing individual cases of subclinical mastitis in sheep, once had a good relationship with the microbiological examination. In the antibiogram where most of the isolated agents appear sensitive to different antibiotics tested, the antibiotics with the best efficiency were florfenicol and cefoxitin.

  8. [Genotyping and drug resistance of methicillin-resistant Staphylococcus aureus].

    Science.gov (United States)

    Yao, Ming; Guan, Lifeng; Jia, Wei; Wang, Linlin; Li, Gang; Wu, Xuejun; Sun, Tao

    2014-10-01

    To investigate the genotype of staphylococcal chromosomal cassette mec (SCCmec) in methicillin-resistant Staphylococcus aureus (MRSA) isolated from burn wards and its current status of drug resistance. One hundred and seventy-nine strains of Staphylococcus aureus were isolated from wound excretion, blood, and sputum samples of patients that were admitted to ICU or public wards of our Department of Burns and Plastic Surgery from September 2012 to September 2013. Among them, 68 strains were from ICU and 111 strains from public wards. The MRSA phenotype of Staphylococcus aureus was detected with cefoxitin K-B disk diffusion method, and the isolation rates of MRSA in ICU and public wards were compared. Genotyping of SCCmec was performed by PCR in strains of MRSA. In the meantime, the identification result of MRSA by K-B method was verified through detecting methicillin-resistant determinant mecA. The antimicrobial resistance of MRSA and methicillin-sensitive Staphylococcus aureus (MSSA) to 23 kinds of commonly used antibiotics in clinic were detected by K-B disk diffusion method. Except for the antibiotics to which the resistant rates of MRSA were 100.0% or 0, the resistant rates of SCCmecIII MRSA and non-SCCmec III MRSA to the rest of antibiotics were compared. Data were processed with Pearson chi-square test or corrected chi-square test. One hundred and forty-eight strains out of the 179 Staphylococcus aureus were identified as MRSA (accounting for 82.7%), among which 62 were originated from ICU and 86 from public wards. The rest 31 strains of Staphylococcus aureus were MSSA, accounting for 17.3%. The percentage of MRSA in the isolated Staphylococcus aureus was 91.2% (62/68) in ICU, which was significantly higher than that in the public wards [77.5% (86/111), χ2 = 5.526, P = 0.019]. PCR detection showed that the 148 strains of MRSA harbored the mecA gene, out of which 106 strains were SCCmec III positive, accounting for 71.6%. The percentages of SCCmec III type MRSA

  9. 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