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Sample records for vancomycin-resistant staphylococcus aureus

  1. Prevalence of Methicillin and Vancomycin resistant Staphylococcus aureus colonization in nasopharynx; Amir-Alam hospital, 2005

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    Hasibi M

    2007-07-01

    Full Text Available Background: Staphylococcus aureus is one of the most common causes of nosocomial infections with high morbidity and mortality rate. Traditionally, methicillin resistant staphylococcus aureus has been considered a major nosocomial pathogen in healthcare facilities, but in the past decade, it has been observed emerging in the community as well. Informations regarding hospital microbial colonization could be an important step for prevention of nosocomial infections. Our objective was clarifying the prevalence of methicillin resistant and vancomycin resistant staphylococcus aureus colonization in nasopharynx. Methods: A descriptive cross sectional study was carried on 106 patients and nursing staff of surgery and hemodialysis wards in Amir-Alam hospital from April 2005 to July 2005. The samples were collected from nasal region of cases using cotton swab by two experienced technician and were sent to laboratory for culture and antibiogram. Results: Twenty six (29.5% out of 106 cases were nasopharyngeal carriers of staphylococcus aureus. Eight cases (7.5% had methicillin resistant staphylococcus aureus. The most frequent colonization rate was seen in hemodialysis nursing staff and in all of them methicillin resistant staphylococcus aureus was reported. Carrier rates in hemodialysis patients were twice compared to surgery ward patients. The interesting point was that no sample of vancomycin resistant staphylococcus aureus was isolated. Conclusion: Prevalence of methicillin resistant staphylococcus aureus colonization seems to be increased; therefore proper management for controlling this problem is mandatory. The results of the present study suggest that the prevalence of methicillin resistant staphylococcus aureus infections is higher than was expected in Iran and vigorous preventive strategies should therefore be taken to stop the growth of this major health problem.

  2. Detection of vancomycin resistant Staphylococcus aureus: A comparative study of three different phenotypic screening methods

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    Bhateja P

    2005-01-01

    Full Text Available The objective of this study was to investigate screening methodologies, to detect Staphylococcus aureus strains with decreased susceptibility to vancomycin. Three methods were used to screen 160 Staphylococcus aureus clinical isolates along with ATCC quality control strains. Subsequently, MIC of all these 160 strains were determined by NCCLS methodology. The MIC of all the 160 clinical isolates was < 4µg/mL and were classified as vancomycin susceptible by NCCLS criteria but 23 strains were positive by Hiramatshu method, two grew on MHA (5µg/mL vancomycin while CDC method correctly identified no vancomycin intermediate S.aureus (VISA or vancomycin resistant S.aureus (VRSA strains with reference to there MIC. CDC method was found to be the most appropriate screening methodology for detection of VISA or VRSA for diagnostic laboratories.

  3. First Report on Vancomycin-Resistant Staphylococcus aureus in Bovine and Caprine Milk.

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    Bhattacharyya, Debaraj; Banerjee, Jaydeep; Bandyopadhyay, Samiran; Mondal, Bimalendu; Nanda, Pramod K; Samanta, Indranil; Mahanti, Achintya; Das, Arun K; Das, Gunjan; Dandapat, Premanshu; Bandyopadhyay, Subhasish

    2016-12-01

    The present investigation was carried out to study the vancomycin resistance pattern of Staphylococcus aureus isolates (n = 274) obtained from 352 milk samples of bovine (269) and caprine (63) clinical and subclinical mastitis from different districts of West Bengal, India. Of them, seven isolates (vancomycin-resistant S. aureus [VRSA] 1-7) exhibited resistance to vancomycin. Minimum inhibitory concentration of vancomycin (MICvan) for VRSA2 and VRSA3 was ≥16 μg/ml; thus categorized as VRSA. For rest of the isolates, MICvan was 8 μg/ml and they were grouped as vancomycin intermediate S. aureus (VISA). Even though all the isolates were resistant to cefoxitin and oxacillin and possessed mecA gene, none of them carried vancomycin resistance gene. Furthermore, all the seven isolates were subjected to Staphylococcal cassette chromosome mec (SCCmec) typing, Staphylococcal protein A (spa) typing, and enterobacterial repetitive intergenic consensus polymerase chain reaction. All the isolates except VRSA3 and VRSA4 from Kolkata district exhibited diverse genetic lineage, irrespective of their host and antibiotic resistance pattern. These two isolates showed clonal similarity (MRSA-SCCmec-V-spa t267) with methicillin-resistant S. aureus (MRSA) strains previously reported in human and animal infection. Isolation of VRSA and VISA could probably be due to intensive use of vancomycin in healthcare premises, which might have led to the development of glycopeptide-resistant strains and thereafter, further disseminated in the environment, including livestock farms. Detection of VRSA in milk is a serious concern as it may further cause health problems in the consumers. This is the first ever report of VRSA in food animals, even though the pathogen is otherwise prevalent in humans.

  4. Vancomycin Resistance in Staphylococcus aureus
.

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    McGuinness, Will A; Malachowa, Natalia; DeLeo, Frank R

    2017-06-01

    The evolution of Staphylococcus aureus during the modern antibiotic era has been delineated by distinct strain emergence events, many of which include acquisition of antibiotic resistance. The relative high burden of methicillin-resistant S. aureus (MRSA) in healthcare and community settings is a major concern worldwide. Vancomycin, a glycopeptide antibiotic that inhibits cell wall biosynthesis, remains a drug of choice for treatment of severe MRSA infections. S. aureus strains exhibiting increased resistance to vancomycin, known as vancomycin intermediate-resistant S. aureus (VISA) (MIC = 4-8 µg/mL), were discovered in the 1990s. The molecular basis of resistance in VISA is polygenic and involves stepwise mutations in genes encoding molecules predominantly involved in cell envelope biosynthesis. S. aureus isolates with complete resistance to vancomycin (MIC ≥ 16 µg/mL) are termed vancomycin-resistant S. aureus (VRSA)-they were first reported in the U.S. in 2002. Resistance in VRSA is conferred by the vanA gene and operon, which is present on a plasmid. Although treatment of VRSA infections is challenging, the total number of human VRSA infections to date is limited (14 in the U.S.). By comparison, the burden of VISA is relatively high and the molecular mechanisms of resistance are less well-defined. VISA are associated with persistent infections, vancomycin treatment failure, and poor clinical outcomes. Here, we review in brief progress made toward understanding the acquisition of antibiotic resistance in S. aureus, with an emphasis on the molecular mechanisms underlying vancomycin resistance.

  5. Ability of Candida albicans Mutants To Induce Staphylococcus aureus Vancomycin Resistance during Polymicrobial Biofilm Formation▿

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    Harriott, Melphine M.; Noverr, Mairi C.

    2010-01-01

    Candida albicans and Staphylococcus aureus form vigorous polymicrobial biofilms in serum, which may serve as the source of coinfection in patients. More importantly, S. aureus is highly resistant to vancomycin during polymicrobial biofilm formation, with no decreases in bacterial viability observed with up to 1,600 μg/ml drug. In these mixed-species biofilms, S. aureus preferentially associates with C. albicans hyphae, which express a variety of unique adhesins. We tested C. albicans mutants deficient in transcriptional regulators of morphogenesis (CPH1 and EFG1) and biofilm formation (BCR1) to investigate the role of hyphae in mediating polymicrobial biofilm formation. These mutants also have reduced expression of hypha-specific adhesins. The ability to form polymicrobial biofilms correlated with the ability to form hyphae in these mutants. However, only mutants that could adhere to the abiotic surface could induce S. aureus vancomycin resistance, regardless of the presence of hyphae. In examining factors that may mediate interspecies adhesion, we found that the C. albicans ALS family of adhesins (Als1 to Als7 and Als9) was not involved, and neither was the hypha-specific adhesin Hwp1. Therefore, polymicrobial biofilm formation and subsequent antibiotic resistance is a multifactorial process that may require a unique combination of fungal and/or bacterial adhesins. PMID:20566760

  6. Report-Isolation identification and control of vancomycin resistant Staphylococcus aureus.

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    Liaqat, Fakhra; Sheikh, Ali Ahmad; Nazir, Jawad; Hussain, Tanveer; Rabbani, Masood; Shaheen, Arfat Yousaf; Muhammad, Javed

    2015-05-01

    Vancomycin resistant Staphylococcus aureus (VRSA) has been reported from many parts of the world including Asian countries. Hence, main objective of study was to evaluate the possible occurrence of VRSA in hospitals of Lahore city and to ensure the effectiveness of various substitute therapeutic options. A total of 150 samples of pus/wounds were collected from three hospitals of the city and VRSA were isolated and confirmed through recommended method of Clinical and Laboratory Standards Institute. Out of 51 (49.04%) methicillin resistant S. aureus (MRSA) isolates, 5 (9.8%) were found resistant to vancomycin. Minimum inhibitory concentration (MIC) of Linezolid (LZD), Moxifloxacin (MFX) and Clindamycin (CD) were calculated against VRSA isolates by broth microdilution test. All 5 (100%) isolates were susceptible to Linezolid and Clindamycin, while 4 (80%) were susceptible to Moxifloxacin. Ethanolic extracts of Turmeric, Mint, Coriander, Garlic, Kalonji, Cinnamon and Cloves illustrate average MIC values of 140.8 μg/mL, 563.2 μg/mL, 486.4 μg/mL, 614.4 μg/mL, 409.6 μg/mL, 281.6 μg/mL and 64 μg/mL, respectively against 5 VRSA strains. Concentration dependent increase in growth inhibition zones of ethanolic plant extract was recorded by agar well diffusion test. This study was helpful to find out the effective antibiotic against VRSA. Plant extracts encompass anti-staphylococcal activity and this finding demands necessity of further exploration of potential found in these natural herb.

  7. Fitness cost of VanA-type vancomycin resistance in methicillin-resistant Staphylococcus aureus.

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    Foucault, Marie-Laure; Courvalin, Patrice; Grillot-Courvalin, Catherine

    2009-06-01

    We have quantified the biological cost of VanA-type glycopeptide resistance due to the acquisition of the resistance operon by methicillin-resistant Staphylococcus aureus (MRSA) from Enterococcus sp. Exponential growths of recipient strain HIP11713, its transconjugant VRSA-1, VRSA-5, and VRSA-6 were compared in the absence or, except for HIP11713, in the presence of vancomycin. Induction of resistance was performed by adding vancomycin in both the preculture and the culture or the culture at only 1/50 the MIC. In the absence of vancomycin, the growth rates of the vancomycin-resistant S. aureus (VRSA) strains were similar to that of susceptible MRSA strain HIP11713. When resistance was induced, and under both conditions, there was a significant reduction of the growth rate of the VRSA strains relative to that of HIP11713 and to those of their noninduced counterparts, corresponding to a ca. 20% to 38% reduction in fitness. Competition experiments between isogenic VRSA-1 and HIP11713 mixed at a 1:1, 1:100, or 100:1 ratio revealed a competitive disadvantage of 0.4% to 3% per 10 generations of the transconjugant versus the recipient. This slight fitness burden can be attributed to the basal level of expression of the van genes in the absence of induction combined with a gene dosage effect due to the presence of the van operon on multicopy plasmids. These data indicate that VanA-type resistance, when induced, is highly costly for the MRSA host, whereas in the absence of induction, its biological cost is minimal. Thus, the potential for the dissemination of VRSA clinical isolates should not be underestimated.

  8. VanA and VanB Positive Vancomycin-resistant Staphylococcus aureus Among Clinical Isolates in Shiraz, South of Iran

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    Sareh Saadat

    2014-09-01

    Full Text Available Objective: The purpose of this study was to determine the prevalence of vancomycin-resistant Staphylococcus aureus isolated from clinical samples in Shiraz hospitals. Methods: From March to December 2012, 100 S. aureus isolates (mainly from wound and blood were collected from three hospitals in Shiraz, south of Iran. After identification of Staphylococcus aureus by biochemical, microbiological and molecular methods, antibiotic susceptibility testing was performed by Kirby-Bauer disc diffusion test for 13 different antibiotics. Vancomycin-resistant Staphylococcus aureus isolates were determined by vancomycin agar screening test and PCR for vancomycin resistant genes (vanA and vanB. Results: The lowest and highest resistance was seen for quinupristin-dalfopristin (n=1 and ampicillin (n=95, respectively. Vancomycin agar screening test showed that 37 isolates can grow on these media. Further study by PCR also detected vanA and/or vanB genes in all of these strains. Also, 19 isolates showed either vanA or vanB but were susceptible according to vancomycin agar screening test. In total, vanA and vanB resistant genes were detected in 34% and 37% of clinical isolates, respectively. Conclusion: The results showed that the frequency of vancomycin resistance genes (vanA, vanB is very high in Staphylococcus aureus strains isolated from patients in south of Iran. Thus, urgent interventions are needed to keep the emergence and transmission of these isolates to a minimum.

  9. Prevalence of Methicillin and Vancomycin resistant Staphylococcus aureus colonization in nasopharynx; Amir-Alam hospital, 2005

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    Hasibi M.; Iravani BM

    2007-01-01

    Background: Staphylococcus aureus is one of the most common causes of nosocomial infections with high morbidity and mortality rate. Traditionally, methicillin resistant staphylococcus aureus has been considered a major nosocomial pathogen in healthcare facilities, but in the past decade, it has been observed emerging in the community as well. Informations regarding hospital microbial colonization could be an important step for prevention of nosocomial infections. Our objective was clarifying ...

  10. Identification of putative drug targets in Vancomycin-resistant Staphylococcus aureus (VRSA) using computer aided protein data analysis.

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    Hasan, Md Anayet; Khan, Md Arif; Sharmin, Tahmina; Hasan Mazumder, Md Habibul; Chowdhury, Afrin Sultana

    2016-01-01

    Vancomycin-resistant Staphylococcus aureus (VRSA) is a Gram-positive, facultative aerobic bacterium which is evolved from the extensive exposure of Vancomycin to Methicillin resistant S. aureus (MRSA) that had become the most common cause of hospital and community-acquired infections. Due to the emergence of different antibiotic resistance strains, there is an exigency to develop novel drug targets to address the provocation of multidrug-resistant bacteria. In this study, in-silico genome subtraction methodology was used to design potential and pathogen specific drug targets against VRSA. Our study divulged 1987 proteins from the proteome of 34,549 proteins, which have no homologues in human genome after sequential analysis through CD-HIT and BLASTp. The high stringency analysis of the remaining proteins against database of essential genes (DEG) resulted in 169 proteins which are essential for S. aureus. Metabolic pathway analysis of human host and pathogen by KAAS at the KEGG server sorted out 19 proteins involved in unique metabolic pathways. 26 human non-homologous membrane-bound essential proteins including 4 which were also involved in unique metabolic pathway were deduced through PSORTb, CELLO v.2.5, ngLOC. Functional classification of uncharacterized proteins through SVMprot derived 7 human non-homologous membrane-bound hypothetical essential proteins. Study of potential drug target against Drug Bank revealed pbpA-penicillin-binding protein 1 and hypothetical protein MQW_01796 as the best drug target candidate. 2D structure was predicted by PRED-TMBB, 3D structure and functional analysis was also performed. Protein-protein interaction network of potential drug target proteins was analyzed by using STRING. The identified drug targets are expected to have great potential for designing novel drugs against VRSA infections and further screening of the compounds against these new targets may result in the discovery of novel therapeutic compounds that can be

  11. Emergence of vancomycin resistant Staphylococcus aureus (VRSA from a tertiary care hospital from northern part of India

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    Sen Malay

    2006-10-01

    Full Text Available Abstract Background Glycopeptides such as vancomycin are frequently the antibiotics of choice for the treatment of infections caused by methicillin resistant Staphylococcus aureus (MRSA. For the last 7 years incidence of vancomycin intermediate S. aureus and vancomycin resistant S. aureus (VISA and VRSA respectively has been increasing in various parts of the world. The present study was carried out to find out the presence of VISA and VRSA in the northern part of India. Methods A total 1681 staphylococcal isolates consisting of 783 S. aureus and 898 coagulase negative staphylococci (CoNS were isolated from different clinical specimens from various outpatient departments and wards. All S. aureus and 93 CoNS were subjected to MIC testing (against vancomycin, teicolplanin and oxacillin; Brain Heart Infusion (BHI vancomycin screen agar test; disc diffusion testing, and PCR for mecA, vanA and vanB genes detection. Results Out of 783 S. aureus two S. aureus strains were found to be vancomycin and teicoplanin resistant (one strain with MIC 32 μg/ml and the other strain with MIC 64 μg/ml; six strains of S. aureus have shown to be vancomycin intermediate (two strains with MIC 16 μg/ml and four strains with MIC 8 μg/ml; and two strains with teicoplanin intermediate (MIC 16 μg/ml. One CoNS strain was resistant to vancomycin and teicoplanin (MIC 32 μg/ml, and two CoNS strains were intermediate to vancomycin and teicoplanin (MIC 16 μg/ml. All VRSA, VISA and vancomycin resistant CoNS had shown growth on BHI vancomycin screen agar (vancomycin 6 μg/ml and were mecA PCR positive. None of these isolates have demonstrated vanA/vanB gene by PCR. Conclusion The present study reveals for the first time emergence of VISA/VRSA from this part of world and indicates the magnitude of antibiotic resistance in and around the study area. The major cause of this may be unawareness and indiscriminate use of broad-spectrum antibiotics.

  12. Design and synthesis of benzenesulfonanilides active against methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus.

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    Namba, Kensuke; Zheng, Xiaoxia; Motoshima, Kazunori; Kobayashi, Hidetomo; Tai, Akihiro; Takahashi, Eizo; Sasaki, Kenji; Okamoto, Keinosuke; Kakuta, Hiroki

    2008-06-01

    Vancomycin is mainly used as an antibacterial agent of last resort, but recently vancomycin-resistant bacterial strains have been emerging. Although new antimicrobials have been developed in order to overcome drug-resistant bacteria, many are structurally complex beta-lactams or quinolones. In this study, we aimed to create new anti-drug-resistance antibacterials which can be synthesized in a few steps from inexpensive starting materials. Since sulfa drugs function as p-aminobenzoic acid mimics and inhibit dihydropteroate synthase (DHPS) in the folate pathway, we hypothesized that sulfa derivatives would act as folate metabolite-mimics and inhibit bacterial folate metabolism. Screening of our sulfonanilide libraries, including benzenesulfonanilide-type cyclooxygenase-1-selective inhibitors, led us to discover benzenesulfonanilides with potent anti-methicillin-resistant Staphylococcus aureus (MRSA)/vancomycin-resistant Enterococcus (VRE) activity, that is, N-3,5-bis(trifluoromethyl)phenyl-3,5-dichlorobenzenesulfonanilide (16b) [MIC=0.5microg/mL (MRSA), 1.0microg/mL (VRE)], and 3,5-bis(trifluoromethyl)-N-(3,5-dichlorophenyl)benzenesulfonanilide (16c) [MIC=0.5microg/mL (MRSA), 1.0microg/mL (VRE)]. These compounds are more active than vancomycin [MIC=2.0microg/mL (MRSA), 125microg/mL (VRE)], but do not possess an amino group, which is essential for DHPS inhibition by sulfa drugs. These results suggested that the mechanism of antibacterial action of compounds 16b and 16c is different from that of sulfa drugs. We also confirmed the activity of these compounds against clinical isolates of Gram-positive bacteria.

  13. Plectranthus amboinicus essential oil and carvacrol bioactive against planktonic and biofilm of oxacillin- and vancomycin-resistant Staphylococcus aureus.

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    Vasconcelos, Sara Edwirgens Costa Benício; Melo, Hider Machado; Cavalcante, Theodora Thays Arruda; Júnior, Francisco Eduardo Aragão Catunda; de Carvalho, Mário Geraldo; Menezes, Francisca Gleire Rodrigues; de Sousa, Oscarina Viana; Costa, Renata Albuquerque

    2017-09-16

    The emergence of multidrug-resistant bacteria is a worldwide concern and in order to find an alternative to this problem, the occurrence of antimicrobial compounds in Plectranthus amboinicus essential oil was investigated. Thus, this study aims to determine susceptibility of Staphylococcus aureus isolated from food to antibiotics, P. amboinicus essential oil (PAEO) and carvacrol. Leaves and stem of P. amboinicus were used for extraction of essential oil (PAEO) by hydrodistillation technique and EO chemical analysis was performed by gas chromatography coupled to a mass spectrometer. S. aureus strains (n = 35) isolated from food and S. aureus ATCC 6538 were used to evaluate the antimicrobial and antibiofilm activity of PAEO and carvacrol. All strains (n = 35) were submitted to antimicrobial susceptibility profile by disk diffusion method. Determination of MIC and MBC was performed by microdilution technique and antibiofilm activity was determined by microtiter-plate technique with crystal violet assay and counting viable cells in Colony Forming Units (CFU). Carvacrol (88.17%) was the major component in the PAEO. Antibiotic resistance was detected in 28 S. aureus strains (80%) and 12 strains (34.3%) were oxacillin and vancomycin-resistant (OVRSA). From the 28 resistant strains, 7 (25%) showed resistance plasmid of 12,000 bp. All strains (n = 35) were sensitive to PAEO and carvacrol, with inhibition zones ranging from 16 to 38 mm and 23 to 42 mm, respectively. The lowest MIC (0.25 mg mL-1) and MBC (0.5 mg mL-1) values were observed when carvacrol was used against OVRSA. When a 0.5 mg mL-1 concentration of PAEO and carvacrol was used, no viable cells were found on S. aureus biofilm. The antibacterial effect of carvacrol and PAEO proves to be a possible alternative against planktonic forms and staphylococcal biofilm.

  14. Activated ADI pathway: the initiator of intermediate vancomycin resistance in Staphylococcus aureus.

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    Tan, Xin-Ee; Neoh, Hui-Min; Looi, Mee-Lee; Chin, Siok Fong; Cui, Longzhu; Hiramatsu, Keiichi; Hussin, Salasawati; Jamal, Rahman

    2017-03-01

    Comparative proteomic profiling between 2 vancomycin-intermediate Staphylococcus aureus (VISA) strains, Mu50Ω-vraSm and Mu50Ω-vraSm-graRm, and vancomycin-susceptible S. aureus (VSSA) strain Mu50Ω revealed upregulated levels of catabolic ornithine carbamoyltransferase (ArcB) of the arginine catabolism pathway in VISA strains. Subsequent analyses showed that the VISA strains have higher levels of cellular ATP and ammonia, which are by-products of arginine catabolism, and displayed thicker cell walls. We postulate that elevated cytoplasmic ammonia and ATP molecules, resulting from activated arginine catabolism upon acquisition of vraS and graR mutations, are important requirements facilitating cell wall biosynthesis, thereby contributing to thickened cell wall and consequently reduced vancomycin susceptibility in VISA strains.

  15. High-Level Vancomycin-Resistant Staphylococcus aureus (VRSA in Iran: A Systematic Review

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    Emran Askari

    2015-10-01

    Full Text Available Background: Staphylococcus aureus is a major human pathogen world- wide. Vancomycin has been used for decades to treat multidrug resistant S. aureus. Ten years has passed since the first report of vancomycin re- sistant S. aureus (VRSA. The objective of this systematic review was to determine  the total number of VRSA isolates that have been reported from Iran.Methods:  Search terms reflected “Iran”, “vancomycin” and “S. aureus” were  searched  in the ISI web  of knowledge,  PubMed,  SciVerse,  and Google scholar. Also two Persian scientific databases and 13 recent na- tional congresses  were investigated.  Articles / abstracts working on S. aureus in Iran, evaluating vancomycin MIC and / or PCR of vanA/B were included in this systematic review.Results: Out of the 3484 records found in mentioned resources, 13 re-lated studies were included in the final analysis. The result showed that at least 24 VRSA isolates which have been reported from Iran up to Sep- tember 2012.Conclusion: It seems that many Iranian researchers did not follow a spe- cific guideline for reporting and confirming VRSA. Establishing an Ira- nian reference center where studies on VRSA can be registered, evaluat- ed and confirmed is strongly recommended.

  16. Vancomycin activates σ(B in vancomycin-resistant Staphylococcus aureus resulting in the enhancement of cytotoxicity.

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    Hong-Yi Chen

    Full Text Available The alternative transcription factor σ(B is responsible for transcription in Staphylococcus aureus during the stress response. Many virulence-associated genes are directly or indirectly regulated by σ(B. We hypothesized that treatment with antibiotics may act as an environmental stressor that induces σ(B activity in antibiotic-resistant strains. Several antibiotics with distinct modes of action, including ampicillin (12 µg/ml, vancomycin (16 or 32 µg/ml, chloramphenicol (15 µg/ml, ciprofloxacin (0.25 µg/ml, and sulfamethoxazole/trimethoprim (SXT, 0.8 µg/ml, were investigated for their ability to activate this transcription factor. We were especially interested in the stress response in vancomycin-resistant S. aureus (VRSA strains treated with vancomycin. The transcription levels of selected genes associated with virulence were also measured. Real-time quantitative reverse transcription PCR was employed to evaluate gene transcription levels. Contact hemolytic and cytotoxicity assays were used to evaluate cell damage following antibiotic treatment. Antibiotics that target the cell wall (vancomycin and ampicillin and SXT induced σ(B activity in VRSA strains. Expression of σ(B-regulated virulence genes, including hla and fnbA, was associated with the vancomycin-induced σ(B activity in VRSA strains and the increase in cytotoxicity upon vancomycin treatment. These effects were not observed in the sigB-deficient strain but were observed in the complemented strain. We demonstrate that sub-minimum inhibitory concentration (sub-MIC levels of antibiotics act as environmental stressors and activate the stress response sigma factor, σ(B. The improper use of antibiotics may alter the expression of virulence factors through the activation of σ(B in drug-resistant strains of S. aureus and lead to worse clinical outcomes.

  17. [Study of marine actinomycetes isolated from the central coast of Peru and their antibacterial activity against methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecalis].

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    León, Jorge; Aponte, Juan José; Rojas, Rosario; Cuadra, D'Lourdes; Ayala, Nathaly; Tomás, Gloria; Guerrero, Marco

    2011-06-01

    To determine the antimicrobial potential of marine actinomycetes against drug-resistant pathogens represented by strains of methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecalis (VRE). Strains of actinomycetes (29) isolated from marine sediment were evaluated by their characteristics in two culture media and by testing their inhibitory capacity by in vitro antagonism against multi-drug resistant (MDR) pathogenic bacteria for MRSA and VRE. Organic extracts of 3 selected actinomicetes were processed to determine the minimum inhibitory concentration (MIC) of the active compound. Most isolated actinomycetes belong to a homogeneous group of write-gray actinomycetes with a good growth in Marine Agar. The inhibitory rates of the isolates were above 85% for both pathogens with inhibition zones greater than 69 and 78 mm in diameter for MRSA and VRE respectively. Dichloromethane extracts of 3 isolates (I-400A, B1-T61, M10-77) showed strong inhibitory activity of both pathogens, M10-77 being the highest actinomycete strain with antibiotic activity against methicillin-resistant S. aureus ATCC 43300 and vancomycin-resistant E. faecalis ATCC 51299 with a minimum inhibitory concentrations (MIC) of 7.9 and 31.7 μg/ml respectively. Phylogenetic analysis of M10-77 strain showed 99% similarity with the marine species Streptomyces erythrogriseus. Marine sediments of the central coast of Peru, are a source of actinomycetes strains showing high capacity to produce bioactive compounds able to inhibit pathogens classified as multi-drug-resistant such as methicillin-resistant S. aureus and vancomycin-resistant E. faecalis.

  18. Reduction in hospital-associated methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus with daily chlorhexidine gluconate bathing for medical inpatients.

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    Lowe, Christopher F; Lloyd-Smith, Elisa; Sidhu, Baljinder; Ritchie, Gordon; Sharma, Azra; Jang, Willson; Wong, Anna; Bilawka, Jennifer; Richards, Danielle; Kind, Thomas; Puddicombe, David; Champagne, Sylvie; Leung, Victor; Romney, Marc G

    2017-03-01

    Daily bathing with chlorhexidine gluconate (CHG) is increasingly used in intensive care units to prevent hospital-associated infections, but limited evidence exists for noncritical care settings. A prospective crossover study was conducted on 4 medical inpatient units in an urban, academic Canadian hospital from May 1, 2014-August 10, 2015. Intervention units used CHG over a 7-month period, including a 1-month wash-in phase, while control units used nonmedicated soap and water bathing. Rates of hospital-associated methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) colonization or infection were the primary end point. Hospital-associated S. aureus were investigated for CHG resistance with a qacA/B and smr polymerase chain reaction (PCR) and agar dilution. Compliance with daily CHG bathing was 58%. Hospital-associated MRSA and VRE was decreased by 55% (5.1 vs 11.4 cases per 10,000 inpatient days, P = .04) and 36% (23.2 vs 36.0 cases per 10,000 inpatient days, P = .03), respectively, compared with control cohorts. There was no significant difference in rates of hospital-associated Clostridium difficile. Chlorhexidine resistance testing identified 1 isolate with an elevated minimum inhibitory concentration (8 µg/mL), but it was PCR negative. This prospective pragmatic study to assess daily bathing for CHG on inpatient medical units was effective in reducing hospital-associated MRSA and VRE. A critical component of CHG bathing on medical units is sustained and appropriate application, which can be a challenge to accurately assess and needs to be considered before systematic implementation. Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  19. Occurrence of Methicillin and Vancomycin Resistant Staphylococcus ...

    African Journals Online (AJOL)

    The susceptibility of clinical isolates of Staphylococcus aureus from a hospital to seven antibiotics; namely ofloxacin, vancomycin, oxacillin, erythromycin ampicillin and gentamicin was examined. The isolates were recovered from wound, skin, urine, blood, vaginal, cerebrospinal fluid and ear infections. After confirmation as ...

  20. Effect of meteorological factors and geographic location on methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci colonization in the US.

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    Blanco, Natalia; Perencevich, Eli; Li, Shan Shan; Morgan, Daniel J; Pineles, Lisa; Johnson, J Kristie; Robinson, Gwen; Anderson, Deverick J; Jacob, Jesse T; Maragakis, Lisa L; Harris, Anthony D

    2017-01-01

    Little is known about the effect of meteorological conditions and geographical location on bacterial colonization rates particularly of antibiotic-resistant Gram-positive bacteria. We aimed to evaluate the effect of season, meteorological factors, and geographic location on methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE) colonization. The prospective cohort included all adults admitted to 20 geographically-dispersed ICUs across the US from September 1, 2011 to October 4, 2012. Nasal and perianal swabs were collected at admission and tested for MRSA and VRE colonization respectively. Poisson regression models using monthly aggregated colonization counts as the outcome and mean temperature, relative humidity, total precipitation, season, and/or latitude as predictors were constructed for each pathogen. A total of 24,704 ICU-admitted patients were tested for MRSA and 24,468 for VRE. On admission, 10% of patients were colonized with MRSA and 12% with VRE. For MRSA and VRE, a 10% increase in relative humidity was associated with approximately a 9% increase in prevalence rate. Southerly latitudes in the US were associated with higher MRSA colonization, while northerly latitudes were associated with higher VRE colonization. In contrast to MRSA, the association between VRE colonization and latitude was observed only after adjusting for relative humidity, which demonstrates how this effect is highly driven by this meteorological factor. To our knowledge, we are the first to study the effect of meteorological factors and geographical location/latitude on MRSA and VRE colonization in adults. Increasing humidity was associated with greater MRSA and VRE colonization. Southerly latitudes in the US were associated with greater MRSA and less VRE. The effect of these factors on MRSA and VRE rates has the potential not only to inform patient management and treatment, but also infection prevention interventions.

  1. Methicillin and vancomycin resistant S. aureus in hospitalized patients

    Directory of Open Access Journals (Sweden)

    Poonam Sood Loomba

    2010-01-01

    Full Text Available S. aureus is the major bacterial cause of skin, soft tissue and bone infections, and one of the commonest causes of healthcare-associated bacteremia. Hospital-associated methicillin-resistant S. aureus (MRSA carriage is associated with an increased risk of infection, morbidity and mortality. Screening of high-risk patients at the time of hospital admission and decolonization has proved to be an important factor in an effort to reduce nosocomial transmission. The electronic database Pub Med was searched for all the articles on "Establishment of MRSA and the emergence of vancomycin-resistant S. aureus (VRSA." The search included case reports, case series and reviews. All the articles were cross-referenced to search for any more available articles. A total of 88 references were obtained. The studies showed a steady increase in the number of vancomycin-intermediate and vancomycin-resistant S. aureus. Extensive use of vancomycin creates a selective pressure that favors the outgrowth of rare, vancomycin-resistant clones leading to heterogenous vancomycin intermediate S. aureus hVISA clones, and eventually, with continued exposure, to a uniform population of vancomycin-intermediate S. aureus (VISA clones. However, the criteria for identifying hVISA strains have not been standardized, complicating any determination of their clinical significance and role in treatment failures. The spread of MRSA from the hospital to the community, coupled with the emergence of VISA and VRSA, has become major concern among healthcare providers. Infection-control measures, reliable laboratory screening for resistance, appropriate antibiotic prescribing practices and avoidance of blanket treatment can prevent long-term emergence of resistance.

  2. Prevalance of vanA Gene in Vancomycine Resistant Staphylococcus Aureus (VRSA) Isolated from Chicken and Turkey Meat in Tehran, Iran

    OpenAIRE

    Amini, M; Hosseini Doust, SR. (PhD); Mohabati Mobarez, A. (PhD)

    2015-01-01

    Background and Objective: Staphylococcus aureus have been isolated frequently from the infection of blood, skin and soft tissue, and is one of the causative agents of food-borne illnesses. The purpose of this study was to investigate the occurrence of vanA in raw meat samples in Tehran, Iran. Material and Methods: Totally, 119 samples of chicken and turkey raw meat were cultured for Staphylococcus aureus. The Resistance to vancomycin was determined and Van A Gene detected by PCR method. Resul...

  3. Bactericidal activities of two daptomycin regimens against clinical strains of glycopeptide intermediate-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus faecium, and methicillin-resistant Staphylococcus aureus isolates in an in vitro pharmacodynamic model with simulated endocardial vegetations

    National Research Council Canada - National Science Library

    Akins, R L; Rybak, M J

    2001-01-01

    .... The mechanism of action is unique, resulting in interference with cell membrane transport. The bactericidal activity of daptomycin was evaluated against glycopeptide-intermediate susceptible Staphylococcus aureus (GISA...

  4. Vancomycin-resistant Staphylococcus hominis endophthalmitis following cataract surgery

    Directory of Open Access Journals (Sweden)

    Won JY

    2013-06-01

    Full Text Available Jun Yeon Won,1 Moosang Kim21Department of Otolaryngology, School of Medicine, Kangwon National University, Chuncheon, Korea; 2Department of Ophthalmology, School of Medicine, Kangwon National University, Chuncheon, KoreaAbstract: We report a case of acute postoperative endophthalmitis caused by vancomycin-resistant Staphylococcus hominis, treated at our hospital. An 80-year-old male presented 2 days after uncomplicated phacoemulsification and posterior chamber intraocular lens implantation, with a 24-hour history of progressive visual loss and redness in the operated (right eye. On examination, best corrected visual acuity was counting fingers. Anterior segment examination revealed conjunctival injection, chemosis, corneal edema, and hypopyon. B-scan ultrasonography showed vitreous opacification, but no retinal detachment. Acute postoperative endophthalmitis was diagnosed. We performed vitrectomy with vancomycin in the irrigating solution, intraocular lens removal, and silicone oil tamponade. Culture of the vitreous grew Staphylococcus hominis. Antibiotic susceptibility testing showed the isolate was sensitive to trimethoprim/sulfamethoxazole and teicoplanin but resistant to ciprofloxacin, moxifloxacin, levofloxacin, cefazolin, and vancomycin. At 3 months, the visual acuity of the silicone oil-treated eye was 20/400.Keywords: endophthalmitis, Staphylococcus hominis, vancomycin

  5. Estudio de actinomicetos marinos aislados de la costa central del Perú y su actividad antibacteriana frente a Staphylococcus aureus Meticilina Resistentes y Enterococcus faecalis Vancomicina Resistentes Study of marine actinomycetes isolated from the central coast of Peru and their antibacterial activity against Methicillin-Resistant Staphylococcus aureus and Vancomycin-Resistant Enterococcus faecalis

    Directory of Open Access Journals (Sweden)

    Jorge León

    2011-06-01

    Full Text Available Objetivos. Determinar el potencial antimicrobiano de actinomicetos marinos frente a cepas S. aureus meticilino-resistentes (MRSA y E. faecalis vancomicina-resistentes (VRE. Materiales y métodos. En dos medios de cultivo se sembraron 29 cepas de actinomicetos aislados de sedimento marino. Se evaluó la capacidad inhibitoria mediante pruebas de antagonismo in vitro para MRSA y VRE. Se procesó los extractos orgánicos de tres actinomicetos seleccionados para determinar la Concentración Mínima Inhibitoria (CMI del compuesto activo. Resultados. La mayoría de los actinomicetos aislados correspondieron a un grupo homogéneo de blanco-grisáceos (62% con buen nivel de crecimiento en agar marino. Los porcentajes inhibitorios fueron superiores a 85% para ambos patógenos con halos de inhibición mayores a 69 y 78 mm de diámetro para MRSA y VRE respectivamente. Los extractos diclorometánicos de tres de los actinomicetos aislados (I-400A, B1-T61, M10-77 mostraron gran potencial inhibitorio de ambos patógenos, siendo M10-77 la cepa de actinomiceto de mayor actividad antibiótica frente a S. aureus ATCC 43300 resistente a meticilina y E. faecalis ATCC 51299 resistente a vancomicina con una Concentración Mínima Inhibitoria (CMI de 7,9 y 31,7 μg/ mL respectivamente. El análisis filogenético de la cepa M10- 77 presenta un 99% de similaridad con la especie marina Streptomyces erythrogriseus. Conclusiones. El sedimento marino de la costa central del Perú es fuente promisorio de cepas de actinomicetos con gran capacidad de producir compuestos bioactivos capaces de inhibir patógenos tipificados como multidrogo-resistentes tales como S. aureus meticilino resistentes y E. faecalis vancomicina resistentes.Objectives. To determine the antimicrobial potential of marine actinomycetes against drug-resistant pathogens represented by strains of methicillin-resistant Staphylococcus aureus (MRSA and vancomycin-resistant Enterococcus faecalis (VRE. Materials and

  6. A Discrete Event Simulation Model of Patient Flow in a General Hospital Incorporating Infection Control Policy for Methicillin-Resistant Staphylococcus Aureus (MRSA) and Vancomycin-Resistant Enterococcus (VRE).

    Science.gov (United States)

    Shenoy, Erica S; Lee, Hang; Ryan, Erin E; Hou, Taige; Walensky, Rochelle P; Ware, Winston; Hooper, David C

    2018-02-01

    Hospitalized patients are assigned to available staffed beds based on patient acuity and services required. In hospitals with double-occupancy rooms, patients must be additionally matched by gender. Patients with methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococcus (VRE) must be bedded in single-occupancy rooms or cohorted with other patients with similar MRSA/VRE flags. We developed a discrete event simulation (DES) model of patient flow through an acute care hospital. Patients are matched to beds based on acuity, service, gender, and known MRSA/VRE colonization. Outcomes included time to bed arrival, length of stay, patient-bed acuity mismatches, occupancy, idle beds, acuity-related transfers, rooms with discordant MRSA/VRE colonization, and transmission due to discordant colonization. Observed outcomes were well-approximated by model-generated outcomes for time-to-bed arrival (6.7 v. 6.2 to 6.5 h) and length of stay (3.3 v. 2.9 to 3.0 days), with overlapping 90% coverage intervals. Patient-bed acuity mismatches, where patient acuity exceeded bed acuity and where patient acuity was lower than bed acuity, ranged from 0.6 to 0.9 and 8.6 to 11.1 mismatches per h, respectively. Values for observed occupancy, total idle beds, and acuity-related transfers compared favorably to model-predicted values (91% v. 86% to 87% occupancy, 15.1 v. 14.3 to 15.7 total idle beds, and 27.2 v. 22.6 to 23.7 transfers). Rooms with discordant colonization status and transmission due to discordance were modeled without an observed value for comparison. One-way and multi-way sensitivity analyses were performed for idle beds and rooms with discordant colonization. We developed and validated a DES model of patient flow incorporating MRSA/VRE flags. The model allowed for quantification of the substantial impact of MRSA/VRE flags on hospital efficiency and potentially avoidable nosocomial transmission.

  7. Vancomycin Sensitivity of Staphylococcus aureus isolates from ...

    African Journals Online (AJOL)

    Methicillin-resistant Staphylococcus aureus (S. aureus) (MRSA), resistant to all antibiotics including Vancomycin, has been reported in Japan, USA, Canada and Brazil. Hence, the main objective of this study was to evaluate the possible presence of Vancomycin resistant or intermediate S.aureus in Karachi. A total of 850 ...

  8. Fitness Cost of VanA-Type Vancomycin Resistance in Methicillin-Resistant Staphylococcus aureus▿

    Science.gov (United States)

    Foucault, Marie-Laure; Courvalin, Patrice; Grillot-Courvalin, Catherine

    2009-01-01

    We have quantified the biological cost of VanA-type glycopeptide resistance due to the acquisition of the resistance operon by methicillin-resistant Staphylococcus aureus (MRSA) from Enterococcus sp. Exponential growths of recipient strain HIP11713, its transconjugant VRSA-1, VRSA-5, and VRSA-6 were compared in the absence or, except for HIP11713, in the presence of vancomycin. Induction of resistance was performed by adding vancomycin in both the preculture and the culture or the culture at only 1/50 the MIC. In the absence of vancomycin, the growth rates of the vancomycin-resistant S. aureus (VRSA) strains were similar to that of susceptible MRSA strain HIP11713. When resistance was induced, and under both conditions, there was a significant reduction of the growth rate of the VRSA strains relative to that of HIP11713 and to those of their noninduced counterparts, corresponding to a ca. 20% to 38% reduction in fitness. Competition experiments between isogenic VRSA-1 and HIP11713 mixed at a 1:1, 1:100, or 100:1 ratio revealed a competitive disadvantage of 0.4% to 3% per 10 generations of the transconjugant versus the recipient. This slight fitness burden can be attributed to the basal level of expression of the van genes in the absence of induction combined with a gene dosage effect due to the presence of the van operon on multicopy plasmids. These data indicate that VanA-type resistance, when induced, is highly costly for the MRSA host, whereas in the absence of induction, its biological cost is minimal. Thus, the potential for the dissemination of VRSA clinical isolates should not be underestimated. PMID:19332680

  9. Multidrug and vancomycin resistance among clinical isolates of ...

    African Journals Online (AJOL)

    Backgrounds: Staphylococcus aureus has emerged as a major public health concern because of the occurrence of multi-drug resistant strains. This study aimed at investigating the multi-drug and vancomycin resistance profile of S. aureus from different infection sites in some teaching hospitals in Nigeria. Methods: Swabs ...

  10. Staphylococcus aureus and Pregnancy

    Science.gov (United States)

    Staphylococcus aureus (Staph Infection) In every pregnancy, a woman starts out with a 3-5% chance of having a baby with ... from your health care provider. What is a staph infection? Staphylococcus aureus (staph) is a type of ...

  11. Repurposing Thiram and Disulfiram as Antibacterial Agents for Multidrug-Resistant Staphylococcus aureus Infections.

    Science.gov (United States)

    Long, Timothy E

    2017-09-01

    Thiram and disulfiram were evaluated as antibacterial agents against multidrug-resistant Staphylococcus aureus Against a 30-member panel comprised of vancomycin-susceptible, vancomycin-intermediate, and vancomycin-resistant S. aureus strains, the MIC90 values of the respective test agents were 4 and 16 μg/ml. Additional analyses revealed that thiram and disulfiram are rapid-acting bacteriostatic agents with narrow, Gram-positive-bacterium spectrum activity. Synergy studies further determined that disulfiram increases the vancomycin susceptibility of three clinical vancomycin-resistant S. aureus strains in vitro, thus establishing a potential use in combination therapy. Copyright © 2017 American Society for Microbiology.

  12. Frecuencia de aislamiento de Staphylococcus spp meticilina resistentes y Enterococcus spp vancomicina resistentes en hospitales de Cuba Frequency of methicilline-resistant Staphylococcus spp and vancomycin-resistant Enterococcus spp isolates in Cuban hospitals

    Directory of Open Access Journals (Sweden)

    Leonora González Mesa

    2005-12-01

    Cuba , there was no updated data either on the rate of infection by methicilline-resistant Staphylococcus spp or on the circulation of this germ in the community; neither are there reports on vancomycin-resistant Enterococcus spp presence. In this study, 774 strains collected from hospitals in the country were analyzed. The mechanism of resistance was determined by the methods suggested in the NCCLS guidelines. The 9.3 % (23 and 4.0 % (7 of S. aureus isolates from the hospitals and the community respectively were methicilline-resistant carriers of mecA gen whereas 69.9 %(72 of negative Staphylococcus coagulase isolates showed resistance to oxacillin. Also, a vancomycin-resistant Enterococcus spp-carrying strain was detected. Our results revealed that in Cuba the methicilline-resistant S. aureus is not a problem neither at hospitals nor at the community setting. Despite the fact that the circulation of these germs in the community setting and also the circulation of vancomycin-resistant Enterococcus spp at hospital setting have been reported for the first time, their frequency is very low as a consequence of the advances in the implementation of policies aimed at a more rational use and consumption of antibiotics.

  13. Biofilm-Forming Staphylococcus epidermidis Expressing Vancomycin Resistance Early after Adhesion to a Metal Surface

    OpenAIRE

    Sakimura, Toshiyuki; Kajiyama, Shiro; Adachi, Shinji; Chiba, Ko; Yonekura, Akihiko; Tomita, Masato; Koseki, Hironobu; Miyamoto, Takashi; Tsurumoto, Toshiyuki; Osaki, Makoto

    2015-01-01

    We investigated biofilm formation and time of vancomycin (VCM) resistance expression after adhesion to a metal surface in Staphylococcus epidermidis. Biofilm-forming Staphylococcus epidermidis with a VCM MIC of 1 μg/mL was used. The bacteria were made to adhere to a stainless steel washer and treated with VCM at different times and concentrations. VCM was administered 0, 2, 4, and 8 hours after adhesion. The amount of biofilm formed was evaluated based on the biofilm coverage rates (BCRs) bef...

  14. Biofilm-Forming Staphylococcus epidermidis Expressing Vancomycin Resistance Early after Adhesion to a Metal Surface

    Directory of Open Access Journals (Sweden)

    Toshiyuki Sakimura

    2015-01-01

    Full Text Available We investigated biofilm formation and time of vancomycin (VCM resistance expression after adhesion to a metal surface in Staphylococcus epidermidis. Biofilm-forming Staphylococcus epidermidis with a VCM MIC of 1 μg/mL was used. The bacteria were made to adhere to a stainless steel washer and treated with VCM at different times and concentrations. VCM was administered 0, 2, 4, and 8 hours after adhesion. The amount of biofilm formed was evaluated based on the biofilm coverage rates (BCRs before and after VCM administration, bacterial viability in biofilm was visually observed using the fluorescence staining method, and the viable bacterial count in biofilm was measured. The VCM concentration required to decrease BCR significantly compared with that of VCM-untreated bacteria was 4 μg/mL, even in the 0 hr group. In the 4 and 8 hr groups, VCM could not inhibit biofilm growth even at 1,024 μg/mL. In the 8 hr group, viable bacteria remained in biofilm at a count of 104 CFU even at a high VCM concentration (1,024 μg/mL. It was suggested that biofilm-forming Staphylococcus epidermidis expresses resistance to VCM early after adhesion to a metal surface. Resistance increased over time after adhesion as the biofilm formed, and strong resistance was expressed 4–8 hours after adhesion.

  15. Staphylococcus aureus toxins.

    Science.gov (United States)

    Otto, Michael

    2014-02-01

    Staphylococcus aureus is a dangerous pathogen that causes a variety of severe diseases. The virulence of S. aureus is defined by a large repertoire of virulence factors, among which secreted toxins play a preeminent role. Many S. aureus toxins damage biological membranes, leading to cell death. In particular, S. aureus produces potent hemolysins and leukotoxins. Among the latter, some were recently identified to lyse neutrophils after ingestion, representing an especially powerful weapon against bacterial elimination by innate host defense. Furthermore, S. aureus secretes many factors that inhibit the complement cascade or prevent recognition by host defenses. Several further toxins add to this multi-faceted program of S. aureus to evade elimination in the host. This review will give an overview over S. aureus toxins focusing on recent advances in our understanding of how leukotoxins work in receptor-mediated or receptor-independent fashions. Published by Elsevier Ltd.

  16. Staphylococcus aureus CC398

    DEFF Research Database (Denmark)

    Price, Lance B.; Stegger, Marc; Hasman, Henrik

    2012-01-01

    Since its discovery in the early 2000s, methicillin-resistant Staphylococcus aureus (MRSA) clonal complex 398 (CC398) has become a rapidly emerging cause of human infections, most often associated with livestock exposure. We applied whole-genome sequence typing to characterize a diverse collectio...

  17. Exposure of Staphylococcus aureus to subinhibitory concentrations of β-lactam antibiotics induces heterogeneous vancomycin-intermediate Staphylococcus aureus.

    Science.gov (United States)

    Roch, Mélanie; Clair, Perrine; Renzoni, Adriana; Reverdy, Marie-Elisabeth; Dauwalder, Olivier; Bes, Michèle; Martra, Annie; Freydière, Anne-Marie; Laurent, Frédéric; Reix, Philippe; Dumitrescu, Oana; Vandenesch, François

    2014-09-01

    Glycopeptides are known to select for heterogeneous vancomycin-intermediate Staphylococcus aureus (h-VISA) from susceptible strains. In certain clinical situations, h-VISA strains have been isolated from patients without previous exposure to glycopeptides, such as cystic fibrosis patients, who frequently receive repeated treatments with beta-lactam antibiotics. Our objective was to determine whether prolonged exposure to beta-lactam antibiotics can induce h-VISA. We exposed 3 clinical vancomycin-susceptible methicillin-resistant Staphylococcus aureus (MRSA) strains to ceftazidime, ceftriaxone, imipenem, and vancomycin (as a control) at subinhibitory concentrations for 18 days in vitro. Population analyses showed progressive increases in vancomycin resistance; seven of the 12 derived strains obtained after induction were classified as h-VISA according to the following criteria: area under the curve (AUC) on day 18/AUC of Mu3 of ≥90% and/or growth on brain heart infusion (BHI) agar with 4 mg/liter vancomycin. The derived isolates had thickened cell walls proportional to the level of glycopeptide resistance. Genes known to be associated with glycopeptide resistance (vraSR, yvqF, SA1703, graRS, walKR, and rpoB) were PCR sequenced; no de novo mutations were observed upon beta-lactam exposure. To determine whether trfA, a gene encoding a glycopeptide resistance factor, was essential in the selection of h-VISA upon beta-lactam pressure, a trfA-knockout strain was generated by allelic replacement. Indeed, beta-lactam exposure of this mutated strain showed no capacity to induce vancomycin resistance. In conclusion, these results showed that beta-lactam antibiotics at subinhibitory concentrations can induce intermediate vancomycin resistance in vitro. This induction required an intact trfA locus. Our results suggest that prior use of beta-lactam antibiotics can compromise vancomycin efficacy in the treatment of MRSA infections. Copyright © 2014, American Society for

  18. 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

    Directory of Open Access Journals (Sweden)

    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.

  19. Azoreductase in Staphylococcus aureus.

    Science.gov (United States)

    Zou, Wen; Cerniglia, Carl E; Chen, Huizhong

    2009-01-01

    Azoreductase(s) catalyze a NAD(P)H-dependent reaction in bacteria to metabolize azo dyes to colorless aromatic amines. Azoreductases from bacteria represent a novel family of enzymes with little similarity to other reductases. This unit will describe the current methods for measuring azoreductase from Staphylococcus aureus, which has been suggested to serve as a model strain to study the azo dye degradation by human skin microflora.

  20. The evolution of Staphylococcus aureus

    NARCIS (Netherlands)

    Deurenberg, Ruud H; Stobberingh, Ellen E

    2008-01-01

    A broad variety of infections, ranging from minor infections of the skin to post-operative wound infections can be caused by Staphylococcus aureus. The adaptive power of S. aureus to antibiotics leaded, in the early 1960s, to the emergence of methicillin-resistant S. aureus (MRSA). The cause of

  1. [Cloxacillin-susceptible Staphylococcus aureus with high MIC to glycopeptides. Ever we use cloxacillin?].

    Science.gov (United States)

    Morales-Cartagena, Alejandra; Lalueza, Antonio; San Juan, Rafael; Aguado, José María

    2015-09-01

    Staphylococcus aureus infections are yet an important cause of morbidity and mortality despite of numerous effective anti-staphylococcal antibiotics available. There has been an increasing incidence of methicillin-resistant strains which might have led to a wider use of vancomycin. This seems to ride alongside a covert progressive increase of S. aureus vancomycin minimum inhibitory concentration. In this way, the emergence of vancomycin-intermediate S. aureus (VISA) strains and heteroresistant-VISA has raised concern for the scarcity of alternative treatment options. Equally alarming, though fortunately less frequent, is the emergence of vancomycin-resistant S. aureus. Ultimately, various debate issues have arisen regarding the emergence of S. aureus strains with decreased vancomycin susceptibility, within the range still considered sensitive. These strains have shown a different clinical behaviour regardless of vancomycin use, both in methicillin resistant and sensitive S. aureus. The emergence of increasing vancomycin-resistance in S. aureus isolates, has stirred up the basis of therapeutic approach in staphylococcal infections. There is yet much to explore to better define the impact of higher vancomycin minimum inhibitory concentration in staphylococcal infections.

  2. Staphylococcus aureus paplitimas hospitalizavimo laikotarpiu

    OpenAIRE

    Maželienė, Žaneta; Kaukėnienė, Renata; Antuševas, Aleksandras; Pavilonis, Alvydas

    2008-01-01

    Objective. To determine the prevalence of Staphylococcus aureus strains among hospitalized patients at the beginning of their hospitalization and during their treatment and the resistance of strains to antibiotics, and to evaluate epidemiologic characteristics of these strains. Patients and methods. Sixty-one patients treated at the Department of Cardiac, Thoracic and Vascular Surgery were examined. Identification of Staphylococcus aureus strains was performed using plasmacoagulase and DNase ...

  3. Recommendations for preventing the spread of vancomycin resistance. Recommendations of the Hospital Infection Control Practices Advisory Committee (HICPAC).

    Science.gov (United States)

    1995-09-22

    Since 1989, a rapid increase in the incidence of infection and colonization with vancomycin-resistant enterococci (VRE) has been reported by U.S. hospitals. This increase poses important problems, including a) the lack of available antimicrobial therapy for VRE infections, because most VRE are also resistant to drugs previously used to treat such infections (e.g., aminoglycosides and ampicillin), and b) the possibility that the vancomycin-resistant genes present in VRE can be transferred to other gram-positive microorganisms (e.g., Staphylococcus aureus). An increased risk for VRE infection and colonization has been associated with previous vancomycin and/or multiantimicrobial therapy, severe underlying disease or immunosuppression, and intraabdominal surgery. Because enterococci can be found in the normal gastrointestinal and female genital tracts, most enterococcal infections have been attributed to endogenous sources within the individual patient. However, recent reports of outbreaks and endemic infections caused by enterococci, including VRE, have indicated that patient-to-patient transmission of the microorganisms can occur either through direct contact or through indirect contact via a) the hands of personnel or b) contaminated patient-care equipment or environmental surfaces. This report presents recommendations of the Hospital Infection Control Practices Advisory Committee for preventing and controlling the spread of vancomycin resistance, with a special focus on VRE. Preventing and controlling the spread of vancomycin resistance will require coordinated, concerted efforts from all involved hospital departments and can be achieved only if each of the following elements is addressed: a) prudent vancomycin use by clinicians, b) education of hospital staff regarding the problem of vancomycin resistance, c) early detection and prompt reporting of vancomycin resistance in enterococci and other gram-positive microorganisms by the hospital microbiology laboratory

  4. [Protein toxins of Staphylococcus aureus].

    Science.gov (United States)

    Shamsutdinov, A F; Tiurin, Iu A

    2014-01-01

    Main scientific-research studies regarding protein bacterial toxins of the most widespread bacteria that belong to Staphylococcus spp. genus and in particular the most pathogenic species for humans--Staphylococcus aureus, are analyzed. Structural and biological properties of protein toxins that have received the name of staphylococcus pyrogenic toxins (PTSAg) are presented. Data regarding genetic regulation of secretion and synthesis of these toxins and 3 main regulatory genetic systems (agr--accessory gene regulator, xpr--extracellular protein regulator, sar--staphylococcal accessory regulator) that coordinate synthesis of the most important protein toxins and enzymes for virulence of S. aureus, are presented.

  5. Penetration of antibiotics through Staphylococcus aureus and Staphylococcus epidermidis biofilms

    National Research Council Canada - National Science Library

    Singh, Rachna; Ray, Pallab; Das, Anindita; Sharma, Meera

    2010-01-01

    This study was carried out to elucidate the role of reduced antibiotic penetration in the resistance of Staphylococcus aureus and Staphylococcus epidermidis biofilms to different antibiotics. The biofilms...

  6. Vancomycin-resistant Enterococcus spp

    DEFF Research Database (Denmark)

    Rathe, Mathias; Kristensen, Lise; Ellermann-Eriksen, Svend

    2010-01-01

    Vancomycin-resistant enterococci (VRE) have emerged to become a significant nosocomial pathogen. However, detection may be challenging and treatment possibilities are limited. Reports of resistance to linezolide, daptomycin and tigecycline underline the need for reliable susceptibility testing...... excellent in vitro activity towards all isolates. For daptomycin and tigecycline, the overall agreement between BMD and Etest was suboptimal. For both disc diffusion assays, use of current break points was inadequate to detect vancomycin resistance for isolates carrying the vanB gene. Inspection...

  7. Stress Responses in Staphylococcus aureus

    DEFF Research Database (Denmark)

    Frees, Dorte; Ingmer, Hanne

    2016-01-01

    Staphylococcus aures are prominent members of the normal flora of humans and animals, but are also a major cause of mild and severe infections. To persist and disseminate in the human host, and to survive in environmental settings, such as hospitals, S. aureus have developed a plethora of cellular...

  8. Multidrug and vancomycin resistance among clinical isolates of ...

    African Journals Online (AJOL)

    2017-09-03

    Sep 3, 2017 ... Rebiahi S, Abdelouahid D, Rahmoun M, Abdelali S,. Azzaoui H. Emergence of vancomycin-resistant Staphylo- coccus aureus identified in the Tlemcen University Hospital. (North-West Algeria). Médecine et maladies infectieuses. 2011; 41:646–651. 68. Manfredi R. Update on the appropriate use of linezol-.

  9. Our experiences with vancomycin-resistant enterococci in Jesenice General hospital

    Directory of Open Access Journals (Sweden)

    Helena Ribič

    2007-11-01

    Full Text Available Background: Vancomycin-resistant enterococci (VRE present a great problem in health care, especially because of their resistance to many groups of antibiotics and because of the way of their spreading in health care and long-term care institutions. Genes responsible for resistance to vancomycin can be transmitted to other species of enterococci and also to other grampositive cocci, for example Staphylococcus aureus. Experts anticipate that failure to control methicilin-resistant S. aureus and VRE may make control of vancomycin-resistant S. aureus impossible.Methods: In the medical microbiology laboratory of Institute Public Health Kranj we perform microbiology diagnosis for Jesenice General Hospital, where surveillance culturing for VRE started in May 2007. Until 15th June, 364 surveillance samples for VRE were taken from 92 patients. We also analysed the results of enterococci that were isolated in our laboratory during routine work in the period from 2004 to 2006.Results: In the three-year period we isolated 1593 strains of enterococci and among them 7 strains were VRE. In the Jesenice General Hospital, the first strain of vancomycin-resistant Enterococcus faecium was isolated in May 2007 in a patient, treated in internal intensive care unit. Nine strains of VRE with the same resistance type in nine patients followed the first case. The first four patients with VRE were moved from the same hospital. Among next six patients the common risk factor was contact with VRE positive patient.Conclusions: Control of VRE strains claims for intensive action. Active surveillance of colonised and infected patients, contact precautions with barrier isolation, intensive hand hygiene measures, aggressive environmental decontamination and prudent use of antimicrobials are needed.

  10. Coagulase-positive staphylococci isolated from chicken meat: pathogenic potential and vancomycin resistance.

    Science.gov (United States)

    Martins, Paula Dalcin; de Almeida, Taiana Trindade; Basso, Ana Paula; de Moura, Tiane Martin; Frazzon, Jeverson; Tondo, Eduardo César; Frazzon, Ana Paula Guedes

    2013-09-01

    Coagulase-positive staphylococci (CPS) cause staphylococcal food poisoning. Recently, these bacteria have received increasing attention due to their potential role in the dissemination of antibiotic resistance markers. The present study aimed to evaluate coagulase-positive staphylococci counts, species distribution, enterotoxin genes prevalence, and the antibiotic resistance profile of CPS isolated from in natura chicken meat. Fifteen frozen and 15 chilled industrialized, uncooked chicken parts or entire carcasses were used. Staphylococcal counts revealed that frozen chicken meat samples displayed the lowest CPS count compared with chilled chicken meat samples (pStaphylococcus aureus (62%) was the most common species, followed by S. intermedius, S. delphini, and S. schleiferi subsp. coagulans (10% each) and S. hyicus (8%). The polymerase chain reaction identification of sea, seb, sec, sed, and see genes revealed that 70% of the isolates harbored at least one enterotoxin gene, with sea and sed being the most frequently encountered ones. Two of the 50 investigated strains harbored three different enterotoxin genes. A high frequency of isolates resistant to penicillin, teicoplanin, oxacillin, and clindamycin was observed, and 80% of CPS were found to be resistant to at least one of the 11 tested antimicrobials. Vancomycin-resistant S. aureus and S. intermedius showed minimum inhibitory concentrations of 512 and 64 μg/mL, respectively. These isolates might indicate the dissemination of vancomycin resistance in the community and imply food safety hazards.

  11. METHICILLIN-RESISTANT STAPHYLOCOCCUS AUREUS (MRSA ...

    African Journals Online (AJOL)

    Nosocomial infections caused by methicillin-resistant strains of Staphylococcus aureus often pose therapeutic dilemma to the clinicians because of the multi resistant nature of these strains of Staphylococcus aureus. Outbreaks of both nosocomial and community acquired infections are also frequent and difficult to control.

  12. (allium sativum) on staphylococcus aureus conjunctivites

    African Journals Online (AJOL)

    INTRODUCTION. Bacterial conjunctivitis is common usually self-limiting. The most common causative organisms are staphylococcus epidermis and staphylococcus aureus (S. aureus). Bacterial conjunctivitis is rarely sight threatening. However, accurate diagnosis and prompt treatment at the primary level is important as it ...

  13. Nasal Carriage of Methicillin Resistant Staphylococcus aureus ...

    African Journals Online (AJOL)

    BACKGROUND: Staphylococcus aureus is one of the major causes of community and hospital acquired infections. The emergence of methicillin resistant strains of Staphylococcus aureus in the hospitals and the community is a serious health problem. The aim of this study was to determine the nasal carriage and ...

  14. Nasal carriage of Meticillin resistance Staphylococcus aureus ...

    African Journals Online (AJOL)

    Gemeda

    BACKGROUND: Staphylococcus aureus is one of the major causes of community and hospital acquired infections. The emergence of methicillin resistant strains of. Staphylococcus aureus in the hospitals and the community is a serious health problem. The aim of this study was to determine the nasal carriage and ...

  15. Antimicrobial resistant coagulase positive Staphylococcus aureus ...

    African Journals Online (AJOL)

    ADEYEYE

    Sokoto Journal of Veterinary Sciences, Volume 11 (Number 1). June, 2013. 51 ... Staphylococcus aureus is an Important agent of food poisoning. In many ..... enterotoxicity of Staphylococcus aureus isolated from the hands and nasal cavities of flight catering employees. Journal of Food. Protection, 11, 1487–1491. Hill JE ...

  16. ENTEROTOXIGENIC STAPHYLOCOCCUS AUREUS IN SHEEP RAW MILK

    OpenAIRE

    G. Giacinti; Amatiste, S.; A. Tammaro; D. Sagrafoli; G. Giangolini; R. Rosati

    2011-01-01

    A total of 366 raw milk samples from 30 sheep farms were examined quantitatively for Staphylococcus aureus. Enterotoxin production by strains of Staphylococcus aureus isolated was investigated. S. aureus was detected in 19 farms (63,3%). The ability to synthetise enterotoxins was found in ten strains (52,6%). Production of staphylococcal enterotoxins C (SEC) was recorded in 6 (60%) and production of SEC together with staphylococcal enterotoxin A (SEA) in 4 (40%) staphylococcal isolates. Raw m...

  17. Staphylococcus aureus Nasal Carriage among Surgical personnel ...

    African Journals Online (AJOL)

    Introduction: Staphylococcus aureus (S. aureus) is one of the most common causes of both community and hospital acquired bacterial infection. There is strong correlation between S aureus nasal carriage and disease progress. Nasal carriage is high among health care workers. Inappropriate usage of antibiotic may

  18. Nasal Carriage of Staphylococcus aureus and Antibiotic ...

    African Journals Online (AJOL)

    Nasal carriage of Staphylococcus aureus has been demonstrated to be a major risk factor for invasive S. aureus infections in various population including children. The extent of S. aureus carriage in Sierra Leonean children is largely unknown. To determine the prevalence and pattern of antibiotic susceptibility of nasal S.

  19. Staphylococcus aureus transmission : clinical and molecular aspects

    NARCIS (Netherlands)

    Bloemendaal, A.L.A.

    2010-01-01

    Staphylococcus aureus is a major pathogen in nosocomial infections. Up to 30% of UCI related infections are caused by S. aureus. In this thesis we explore both clinical and molecular aspects of patient-to-patient transmission of S. aureus. We performed a European ICU study exploring infection

  20. Exfoliative Toxins of Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Michal Bukowski

    2010-05-01

    Full Text Available Staphylococcus aureus is an important pathogen of humans and livestock. It causes a diverse array of diseases, ranging from relatively harmless localized skin infections to life-threatening systemic conditions. Among multiple virulence factors, staphylococci secrete several exotoxins directly associated with particular disease symptoms. These include toxic shock syndrome toxin 1 (TSST-1, enterotoxins, and exfoliative toxins (ETs. The latter are particularly interesting as the sole agents responsible for staphylococcal scalded skin syndrome (SSSS, a disease predominantly affecting infants and characterized by the loss of superficial skin layers, dehydration, and secondary infections. The molecular basis of the clinical symptoms of SSSS is well understood. ETs are serine proteases with high substrate specificity, which selectively recognize and hydrolyze desmosomal proteins in the skin. The fascinating road leading to the discovery of ETs as the agents responsible for SSSS and the characterization of the molecular mechanism of their action, including recent advances in the field, are reviewed in this article.

  1. Structures of Two New Flavonoids and Effects of Licorice Phenolics on Vancomycin-Resistant Enterococcus Species

    Directory of Open Access Journals (Sweden)

    Eerdunbayaer

    2014-03-01

    Full Text Available Since our previous study revealed that several licorice phenolics have antibacterial effects on methicillin-resistant Staphylococcus aureus (MRSA, and suppressive effects on the oxacillin resistance of MRSA, we further investigated effectiveness of licorice constituents on vancomycin-resistant Enterococcus (VRE bacteria, and purified 32 phenolic compounds. Two flavonoids among them were characterized structurally, and identified their structures as demethylglycyrol (31 and 5,7-di-O-methylluteone (32, respectively. Examination of antibacterial effects of licorice phenolics showed that 3-arylcoumarins such as licoarylcoumarin (9 and glycycoumarin (26, and 2-arylcoumarones such as gancaonin I (17, have moderate to potent antibacterial effects on the VRE strains used in this study.

  2. Operon structure of Staphylococcus aureus.

    Science.gov (United States)

    ten Broeke-Smits, Nicole J P; Pronk, Tessa E; Jongerius, Ilse; Bruning, Oskar; Wittink, Floyd R; Breit, Timo M; van Strijp, Jos A G; Fluit, Ad C; Boel, C H Edwin

    2010-06-01

    In bacteria, gene regulation is one of the fundamental characteristics of survival, colonization and pathogenesis. Operons play a key role in regulating expression of diverse genes involved in metabolism and virulence. However, operon structures in pathogenic bacteria have been determined only by in silico approaches that are dependent on factors such as intergenic distances and terminator/promoter sequences. Knowledge of operon structures is crucial to fully understand the pathophysiology of infections. Presently, transcriptome data obtained from growth curves in a defined medium were used to predict operons in Staphylococcus aureus. This unbiased approach and the use of five highly reproducible biological replicates resulted in 93.5% significantly regulated genes. These data, combined with Pearson's correlation coefficients of the transcriptional profiles, enabled us to accurately compile 93% of the genome in operon structures. A total of 1640 genes of different functional classes were identified in operons. Interestingly, we found several operons containing virulence genes and showed synergistic effects for two complement convertase inhibitors transcribed in one operon. This is the first experimental approach to fully identify operon structures in S. aureus. It forms the basis for further in vitro regulation studies that will profoundly advance the understanding of bacterial pathophysiology in vivo.

  3. Staphylococcus aureus resistente a vancomicina.

    Directory of Open Access Journals (Sweden)

    Carlos Andrés Rodríguez

    2005-12-01

    Full Text Available Objetivo. Revisar la evolución y mecanismos moleculares de la resistencia de Staphylococcus aureus a vancomicina. Fuente de los datos. Se consultó la base de datos MEDLINE y se seleccionaron artículos tipo reportes de caso, estudios bioquímicos, de microscopía electrónica y biología molecular pertinentes. Síntesis. Después de casi 40 años de eficacia ininterrumpida de la vancomicina, en 1997 se reportaron los primeros casos de fracaso terapéutico debido a cepas de Staphylococcus aureus con resistencia intermedia, denominadas VISA (concentración inhibitoria mínima, CIM, 8 a 16 ?g/ml, así como a cepas con resistencia heterogénea hVISA (CIM global = 4 ?g/ml, pero con subpoblaciones VISA, en las cuales la resistencia está mediada por engrosamiento de la pared celular y disminución de su entrecruzamiento, lo que afecta la llegada del antibiótico al blanco principal, los monómeros del peptidoglicano en la membrana plasmática. En 2002 se aisló la primera de las 3 cepas reportadas hasta la fecha con resistencia total al antibiótico, denominadas VRSA (CIM>32 ?g/ml, en las que se encontró el transposón Tn1546 proveniente de Enterococcus spp, responsable del reemplazo de la terminación D-Ala-D-Ala por D-Ala-Dlactato en los precursores de la pared celular con pérdida de la afinidad por el glicopéptido. Conclusiones. La resistencia a vancomicina es una realidad en S. aureus, mediada en el caso de VISA por alteraciones en la pared celular que atrapan el antibiótico antes de llegar al sitio de acción, y en el caso de VRSA, por transferencia desde Enterococcus spp. de genes que llevan a la modificación del blanco molecular.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    Ahmed, Mohamed O.; Abuzweda, Abdulbaset R.; Alghazali, Mohamed H.; Elramalli, Asma K.; Amri, Samira G.; Aghila, Ezzeddin Sh.; Abouzeed, Yousef M.

    2010-01-01

    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. PMID:21483574

  6. Methicillin-resistant Staphylococcus aureus (MRSA)

    Science.gov (United States)

    ... resistant Staphylococcus aureus; Hospital-acquired MRSA (HA-MRSA); Staph - MRSA; Staphylococcal - MRSA ... Most staph germs are spread by skin-to-skin contact (touching). A doctor, nurse, other health care provider, or ...

  7. Community acquired Staphylococcus aureus meningitis in adults

    NARCIS (Netherlands)

    Brouwer, Matthijs C.; Keizerweerd, Gabriella D.; de Gans, Jan; Spanjaard, Lodewijk; van de Beek, Diederik

    2009-01-01

    We present 9 patients with community acquired Staphylococcus aureus meningitis. Foci of infection outside the central nervous system were present in 8 (89%) patients, mostly endocarditis and pneumonia. Cardiorespiratory complications occurred frequently and 6 patients died (67%). Identification and

  8. Staphylococcus aureus and hand eczema severity

    DEFF Research Database (Denmark)

    Haslund, P; Bangsgaard, N; Jarløv, J O

    2009-01-01

    BACKGROUND: The role of bacterial infections in hand eczema (HE) remains to be assessed. OBJECTIVES: To determine the prevalence of Staphylococcus aureus in patients with HE compared with controls, and to relate presence of S. aureus, subtypes and toxin production to severity of HE. METHODS......: Bacterial swabs were taken at three different visits from the hand and nose in 50 patients with HE and 50 controls. Staphylococcus aureus was subtyped by spa typing and assigned to clonal complexes (CCs), and isolates were tested for exotoxin-producing S. aureus strains. The Hand Eczema Severity Index...... was used for severity assessment. RESULTS: Staphylococcus aureus was found on the hands in 24 patients with HE and four controls (P

  9. Documentation of vancomycin-resistant Staphylococcus aureus (VRSA) among children with atopic dermatitis in the Qassim region, Saudi Arabia

    National Research Council Canada - National Science Library

    Alzolibani, Abdullateef A; Al Robaee, Ahmad A; Al Shobaili, Hani A; Bilal, Jalal A; Issa Ahmad, Mohammad; Bin Saif, Ghada

    2012-01-01

    .... Swabs were collected from atopic dermatitis skin lesions of 80 children being treated at dermatology clinics whose ages ranged from 6 months to 15 years in the period from March 2009 to February 2010...

  10. Characterization of Staphylococcus aureus nasal colonization rates ...

    African Journals Online (AJOL)

    Carriers of Staphylococcus aureus have an important role in its dissemination. The colonization rates of S. aureus in anterior nose nares from 210 healthy volunteers (70 from the non-hospital adult personnel in the community, 68 from clinical students and 72 from healthcare workers “HCWs” in 6 hospitals) in the eastern ...

  11. Antimicrobial resistant coagulase positive Staphylococcus aureus ...

    African Journals Online (AJOL)

    Staphylococcus aureus is an Important agent of food poisoning. In many countries, it is the main bacterial organism responsible for diseases caused by exotoxin production and direct invasion with systemic dissemination. In poultry, S. aureus is associated with many clinical syndromes including tenosynovitis, omphalitis, ...

  12. Methicillin-resistant staphylococcus aureus (MRSA) colonization ...

    African Journals Online (AJOL)

    Introduction: methicillin-resistant Staphylococcus aureus (MRSA) has been recognized as important nosocomial pathogens worldwide. S aureus may induce clinically manifested diseases, or the host may remain completely asymptomatic. Methods: a cross-sectional hospital-based study was conducted from October 2012 ...

  13. Immunogenicity of toxins during Staphylococcus aureus infection

    NARCIS (Netherlands)

    N.J. Verkaik (Nelianne); O. Dauwalder (Olivier); K. Antri (Kenza); I. Boubekri (Ilhem); C.P. de Vogel (Corné); C. Badiou (Cédric); M. Bes (Michèle); F. Vandenesch (François); M. Tazir (Mohammed); H. Hooijkaas (Herbert); H.A. Verbrugh (Henri); A.F. van Belkum (Alex); J. Etienne (Jerome); G. Lina (Gérard); N. Ramdani-Bouguessa (Nadjia); W.J.B. van Wamel (Willem)

    2010-01-01

    textabstractAB - BACKGROUND: Toxins are important Staphylococcus aureus virulence factors, but little is known about their immunogenicity during infection. Here, additional insight is generated. METHODS: Serum samples from 206 S. aureus-infected patients and 201 hospital-admitted control subjects

  14. Staphylococcus aureus and healthcare-associated infections

    NARCIS (Netherlands)

    Ekkelenkamp, M.B.|info:eu-repo/dai/nl/304817716

    2011-01-01

    Many medical procedures breach or suppress patients’ natural defences, leaving them vulnerable to infections which would not occur in healthy humans: “healthcare-associated infections”. Healthcare-associated infections caused by the bacterium Staphylococcus aureus (S. aureus) are probably the most

  15. 21 CFR 866.3700 - Staphylococcus aureus serological reagents.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Staphylococcus aureus serological reagents. 866... Staphylococcus aureus serological reagents. (a) Identification. Staphylococcus aureus serological reagents are... diagnosis of disease caused by this bacterium belonging to the genus Staphylococcus and provides...

  16. 9 CFR 113.115 - Staphylococcus Aureus Bacterin-Toxoid.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Staphylococcus Aureus Bacterin-Toxoid... REQUIREMENTS Inactivated Bacterial Products § 113.115 Staphylococcus Aureus Bacterin-Toxoid. Staphylococcus... Staphylococcus aureus which has been inactivated and is nontoxic. Each serial of biological product containing...

  17. Frequency of Reduced Vancomycin Susceptibility among Clinical Staphylococcus aureus Isolated in Ahvaz Iran

    Directory of Open Access Journals (Sweden)

    Mojtaba Moosavian

    2015-11-01

    Full Text Available Introduction:   One   of   the   most   important   agents   in   hospital-acquired   infections   is Staphylococcus aureus. Treatment of methicillin-resistant S. aureus (MRSA infections with decreased susceptibility to vancomycin has recently been more difficult. The aim of this study was to evaluate the possible presence of vancomycin intermediate S. aureus (VISA and vancomycin- resistant S. aureus (VRSA and also to determine the frequency of MRSA in clinical specimens.Methods: In this study, 195 S. aureus isolates were collected from the patients were examined. All of the isolates were identified using standard biochemical tests.  Susceptibility of S. aureus isolates against 10 antibiotics was detected by disk diffusion method and was followed by E-test and vancomycin screen agar methods. Minimum inhibitory concentration (MIC of vancomycin was determined according to the CLSI guidelines.  Also, detection of mecA gene was performed by PCR and finally, the results were compared.Results: All of the isolates were susceptible to vancomycin (i.e. MIC range of vancomycin was between 0.25-2 µg/ml. Out of 195 S. aureus isolates, 99 isolates (50.8% were resistant to methicillin, and mecA gene was detected in 96 isolates. These results also showed that the highest and lowest resistance rate of isolates was to penicillin (96.9% and chloramphenicol (0%, respectively.Conclusion: Our findings showed that vancomycin can still be used as a valuable drug for treatment of S. aureus infections in our region. However, periodic evaluation of vancomycin MIC of S. aureus isolates is critical for monitoring MRSA and preventing the spread of VISA or VRSA among patients.

  18. Staphylococcus aureus plasmids without mobilization genes are mobilized by a novel conjugative plasmid from community isolates.

    Science.gov (United States)

    O'Brien, F G; Ramsay, J P; Monecke, S; Coombs, G W; Robinson, O J; Htet, Z; Alshaikh, F A M; Grubb, W B

    2015-03-01

    To describe a family of conjugative plasmids isolated from colonizing community Staphylococcus aureus and determine their ability to mobilize unrelated antimicrobial resistance/virulence plasmids, not encoding mobilization functions. Plasmid pWBG749 was labelled with Tn551 (pWBG749e) to enable laboratory manipulation. Plasmid pWBG749e was conjugated into S. aureus of seven different lineages that harboured unrelated plasmids and mobilization experiments were performed. Plasmids were screened by EcoRI restriction and hybridization with probes prepared from unique pWBG749 conjugation genes. Conjugative plasmids pWBG745, pWBG748 and pWBG749 belong to the same conjugative-plasmid family as the vancomycin resistance plasmid pBRZ01. Plasmid pWBG749e mobilized five unrelated plasmids. Mobilized plasmid pWBG744 is a pIB485-family plasmid that was also found in international S. aureus. Plasmid pWBG749e can mobilize unrelated S. aureus plasmids whose means of dissemination have not previously been understood. © The Author 2014. 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.

  19. Guidelines for the control and prevention of meticillin-resistant Staphylococcus aureus (MRSA) in healthcare facilities.

    Science.gov (United States)

    Coia, J E; Duckworth, G J; Edwards, D I; Farrington, M; Fry, C; Humphreys, H; Mallaghan, C; Tucker, D R

    2006-05-01

    Meticillin-resistant Staphylococcus aureus (MRSA) remains endemic in many UK hospitals. Specific guidelines for control and prevention are justified because MRSA causes serious illness and results in significant additional healthcare costs. Guidelines were drafted by a multi-disciplinary group and these have been finalised following extensive consultation. The recommendations have been graded according to the strength of evidence. Surveillance of MRSA should be undertaken in a systematic way and should be fed back routinely to healthcare staff. The inappropriate or unnecessary use of antibiotics should be avoided, and this will also reduce the likelihood of the emergence and spread of strains with reduced susceptibility to glycopeptides, i.e. vancomycin-intermediate S. aureus/glycopeptide-intermediate S. aureus (VISA/GISA) and vancomycin-resistant S. aureus (VRSA). Screening for MRSA carriage in selected patients and clinical areas should be performed according to locally agreed criteria based upon assessment of the risks and consequences of transmission and infection. Nasal and skin decolonization should be considered in certain categories of patients. The general principles of infection control should be adopted for patients with MRSA, including patient isolation and the appropriate cleaning and decontamination of clinical areas. Inadequate staffing, especially amongst nurses, contributes to the increased prevalence of MRSA. Laboratories should notify the relevant national authorities if VISA/GISA or VRSA isolates are identified.

  20. ENTEROTOXIGENIC STAPHYLOCOCCUS AUREUS IN SHEEP RAW MILK

    Directory of Open Access Journals (Sweden)

    G. Giacinti

    2011-01-01

    Full Text Available A total of 366 raw milk samples from 30 sheep farms were examined quantitatively for Staphylococcus aureus. Enterotoxin production by strains of Staphylococcus aureus isolated was investigated. S. aureus was detected in 19 farms (63,3%. The ability to synthetise enterotoxins was found in ten strains (52,6%. Production of staphylococcal enterotoxins C (SEC was recorded in 6 (60% and production of SEC together with staphylococcal enterotoxin A (SEA in 4 (40% staphylococcal isolates. Raw milk products are vulnerable to contamination by S. aureus. Strategies to reduce the occurrence of S. aureus in bulk milk are of particular importance on farms where milk is used for raw milk products.

  1. Immunomodulation and Disease Tolerance to Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Zhigang Li

    2015-11-01

    Full Text Available The Gram-positive bacterium Staphylococcus aureus is one of the most frequent pathogens that causes severe morbidity and mortality throughout the world. S. aureus can infect skin and soft tissues or become invasive leading to diseases such as pneumonia, endocarditis, sepsis or toxic shock syndrome. In contrast, S. aureus is also a common commensal microbe and is often part of the human nasal microbiome without causing any apparent disease. In this review, we explore the immunomodulation and disease tolerance mechanisms that promote commensalism to S. aureus.

  2. Clinical impact of vancomycin-resistant enterococci

    National Research Council Canada - National Science Library

    Robin Patel

    2003-01-01

    In humans, vancomycin-resistant enterococci (VRE) most commonly result in intestinal colonization, which does not result in symptoms, may persist for a long time and serves as a reservoir for transmission of VRE to other patients...

  3. Bacteriological profiling of diphenylureas as a novel class of antibiotics against methicillin-resistant Staphylococcus aureus.

    Directory of Open Access Journals (Sweden)

    Haroon Mohammad

    Full Text Available Bacterial resistance to antibiotics remains an imposing global public health challenge. Of the most serious pathogens, methicillin-resistant Staphylococcus aureus (MRSA is problematic given strains have emerged that exhibit resistance to several antibiotic classes including β-lactams and agents of last resort such as vancomycin. New antibacterial agents composed of unique chemical scaffolds are needed to counter this public health challenge. The present study examines two synthetic diphenylurea compounds 1 and 2 that inhibit growth of clinically-relevant isolates of MRSA at concentrations as low as 4 µg/mL and are non-toxic to human colorectal cells at concentrations up to 128 μg/mL. Both compounds exhibit rapid bactericidal activity, completely eliminating a high inoculum of MRSA within four hours. MRSA mutants exhibiting resistance to 1 and 2 could not be isolated, indicating a low likelihood of rapid resistance emerging to these compounds. Bacterial cytological profiling revealed the diphenylureas exert their antibacterial activity by targeting bacterial cell wall synthesis. Both compounds demonstrate the ability to resensitize vancomycin-resistant Staphylococcus aureus to the effect of vancomycin. The present study lays the foundation for further investigation and development of diphenylurea compounds as a new class of antibacterial agents.

  4. Molecular analysis and susceptibility patterns of methicillin-resistant Staphylococcus aureus strains causing community- and health care-associated infections in the northern region of Palestine.

    Science.gov (United States)

    Adwan, Kamel; Jarrar, Naser; Abu-Hijleh, Awni; Adwan, Ghaleb; Awwad, Elena; Salameh, Yousef

    2013-03-01

    Community acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) is a major global problem. This study attempted to investigate the prevalence of nasal carriage of Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA) strains among 360 healthy university students at An-Najah National University, Palestine. For the purpose of comparing the staphylococcal cassette chromosome methicillin resistant determinant (SCCmec) type of MRSA, 46 clinical MRSA isolates were also included in this study. Susceptibility testing was performed by the disc diffusion method. The genetic association of MRSA isolates was investigated by SCCmec typing. A selected number of isolates were also used to amplify and sequence mecA. Nasal carriage of S aureus was found in 86 of 360 students (24%). MRSA accounted for 9% of S aureus isolates. All 86 strains of S aureus were sensitive to vancomycin. Resistance to penicillin G, amoxicillin/clavulanic acid, ciprofloxacin, erythromycin, and clindamycin was found in 98%, 93%, 33%, 23%, and 12% of the isolates, respectively. Resistance rates of the MRSA isolates were as follows: 100% resistant to penicillin G and amoxicillin/clavulanic acid, 96% to ethromycin, 52% to clindamycin, and 48% to ciprofloxacin. No vancomycin-resistant isolates were identified. In our study, nearly half (52%) of the MRSA isolates belonged to SCCmec types IVa and V. However, SCCmec types II and III are represented by 48%, whereas SCCmec type I was completely absent. The findings of this study indicate the existence of SCCmec type IVa in both student nasal carriers and health care settings. This emphasizes the need for implementation of a revised set of control measures in both settings. Moreover, the rational prescription of appropriate antibiotics should also be considered. Copyright © 2013 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

  5. The T Cell Response to Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Barbara M. Bröker

    2016-03-01

    Full Text Available Staphylococcus aureus (S. aureus is a dangerous pathogen and a leading cause of both nosocomial and community acquired bacterial infection worldwide. However, on the other hand, we are all exposed to this bacterium, often within the first hours of life, and usually manage to establish equilibrium and coexist with it. What does the adaptive immune system contribute toward lifelong control of S. aureus? Will it become possible to raise or enhance protective immune memory by vaccination? While in the past the S. aureus-specific antibody response has dominated this discussion, the research community is now coming to appreciate the role that the cellular arm of adaptive immunity, the T cells, plays. There are numerous T cell subsets, each with differing functions, which together have the ability to orchestrate the immune response to S. aureus and hence to tip the balance between protection and pathology. This review summarizes the state of the art in this dynamic field of research.

  6. Transforming the untransformable: application of direct transformation to manipulate genetically Staphylococcus aureus and Staphylococcus epidermidis

    National Research Council Canada - National Science Library

    Monk, Ian R; Shah, Ishita M; Xu, Min; Tan, Man-Wah; Foster, Timothy J

    2012-01-01

    The strong restriction barrier present in Staphylococcus aureus and Staphylococcus epidermidis has limited functional genomic analysis to a small subset of strains that are amenable to genetic manipulation...

  7. Antibiograms of Staphylococcus Aureus and Pseudomonas ...

    African Journals Online (AJOL)

    While there was no bacterial growth after 48hrs incubation recorded for group one, only 5(13.9%) samples yielded growth of Staphylococcus aureus for group two with 31(86.1%) yielding no bacterial growth. All group three samples yielded profuse growth of which 11(36.7%) yielded Pseudomonas aeruginosa and ...

  8. Staphylococcus aureus resistente a la meticilina (SARM)

    Centers for Disease Control (CDC) Podcasts

    2007-10-22

    Datos importantes sobre las infecciones por SARM en Estados Unidos, en las escuelas y los entornos médicos. (Title: Methicillin-resistant Staphylococcus aureus (MRSA)Created: 10/2007).  Created: 10/22/2007 by National Center for Preparedness, Detection, and Control of Infectious Diseases.   Date Released: 11/9/2007.

  9. Profiling the surfacome of Staphylococcus aureus

    NARCIS (Netherlands)

    Dreisbach, Annette; Hempel, Kristina; Buist, Girbe; Hecker, Michael; Becher, Doerte; van Dijl, Jan Maarten

    Staphylococcus aureus is a widespread opportunistic pathogen that can cause a wide variety of life-threatening diseases. Especially for the colonization of human tissues and the development of invasiveness, surface-exposed proteins are of major importance. In the present studies, we optimized a

  10. Methicillin-resistant Staphylococcus aureus transmission

    DEFF Research Database (Denmark)

    Andersen, Leif Percival; Nielsen, Xiaohui

    2015-01-01

    INTRODUCTION: Even though methicillin-resistant Staphylococcus aureus (MRSA) is a common cause of nosocomial infections, it may often be difficult to evaluate the exact route of transmission. METHODS: In this study, we describe four cases of nosocomial transmission of MRSA in a hospital with a low...

  11. Staphylococcus aureus spa type t437

    DEFF Research Database (Denmark)

    Glasner, C; Pluister, G; Westh, H

    2015-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) belonging to the multilocus sequence type clonal complex 59 (MLST CC59) is the predominant community-associated MRSA clone in Asia. This clone, which is primarily linked with the spa type t437, has so far only been reported in low numbers among...

  12. Antibiotic susceptibility of Staphylococcus aureus in suppurative ...

    African Journals Online (AJOL)

    Background: Staphylococcus aureus, a mainly acquired hospital infection is responsible for many suppurative lesions and has demonstrated the ability of developing resistance to many antimicrobial agents leading to life threatening infections and long hospital stay. Objective: To determined the prevalence and antibiotic ...

  13. Polyclonal antibodies production against Staphylococcus aureus ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-02-01

    Feb 1, 2010 ... The main aim of this project is to produce polyclonal antibodies directed against the Staphylococcus aureus protein A and their use to appreciate bacteriological analysis of milk quality. In this context, an immunization produce was set up to test and detect in a batch of animals the convenient responder to.

  14. Meticillineresistente Staphylococcus aureus (MRSA) in de gemeenschap

    NARCIS (Netherlands)

    Vonk, A. G.; Vandenbroucke-Grauls, C. M. J. E.

    2007-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) infections have been confined to healthcare centres for decades. However, MRSA infections are increasingly seen in young healthy individuals with no exposure to healthcare centres. These community-acquired MRSA (CA-MRSA) strains differ from

  15. Whole animal automated platform for drug discovery against multi-drug resistant Staphylococcus aureus.

    Directory of Open Access Journals (Sweden)

    Rajmohan Rajamuthiah

    Full Text Available Staphylococcus aureus, the leading cause of hospital-acquired infections in the United States, is also pathogenic to the model nematode Caenorhabditis elegans. The C. elegans-S. aureus infection model was previously carried out on solid agar plates where the bacteriovorous C. elegans feeds on a lawn of S. aureus. However, agar-based assays are not amenable to large scale screens for antibacterial compounds. We have developed a high throughput liquid screening assay that uses robotic instrumentation to dispense a precise amount of methicillin resistant S. aureus (MRSA and worms in 384-well assay plates, followed by automated microscopy and image analysis. In validation of the liquid assay, an MRSA cell wall defective mutant, MW2ΔtarO, which is attenuated for killing in the agar-based assay, was found to be less virulent in the liquid assay. This robust assay with a Z'-factor consistently greater than 0.5 was utilized to screen the Biomol 4 compound library consisting of 640 small molecules with well characterized bioactivities. As proof of principle, 27 of the 30 clinically used antibiotics present in the library conferred increased C. elegans survival and were identified as hits in the screen. Surprisingly, the antihelminthic drug closantel was also identified as a hit in the screen. In further studies, we confirmed the anti-staphylococcal activity of closantel against vancomycin-resistant S. aureus isolates and other Gram-positive bacteria. The liquid C. elegans-S. aureus assay described here allows screening for anti-staphylococcal compounds that are not toxic to the host.

  16. Whole animal automated platform for drug discovery against multi-drug resistant Staphylococcus aureus.

    Science.gov (United States)

    Rajamuthiah, Rajmohan; Fuchs, Beth Burgwyn; Jayamani, Elamparithi; Kim, Younghoon; Larkins-Ford, Jonah; Conery, Annie; Ausubel, Frederick M; Mylonakis, Eleftherios

    2014-01-01

    Staphylococcus aureus, the leading cause of hospital-acquired infections in the United States, is also pathogenic to the model nematode Caenorhabditis elegans. The C. elegans-S. aureus infection model was previously carried out on solid agar plates where the bacteriovorous C. elegans feeds on a lawn of S. aureus. However, agar-based assays are not amenable to large scale screens for antibacterial compounds. We have developed a high throughput liquid screening assay that uses robotic instrumentation to dispense a precise amount of methicillin resistant S. aureus (MRSA) and worms in 384-well assay plates, followed by automated microscopy and image analysis. In validation of the liquid assay, an MRSA cell wall defective mutant, MW2ΔtarO, which is attenuated for killing in the agar-based assay, was found to be less virulent in the liquid assay. This robust assay with a Z'-factor consistently greater than 0.5 was utilized to screen the Biomol 4 compound library consisting of 640 small molecules with well characterized bioactivities. As proof of principle, 27 of the 30 clinically used antibiotics present in the library conferred increased C. elegans survival and were identified as hits in the screen. Surprisingly, the antihelminthic drug closantel was also identified as a hit in the screen. In further studies, we confirmed the anti-staphylococcal activity of closantel against vancomycin-resistant S. aureus isolates and other Gram-positive bacteria. The liquid C. elegans-S. aureus assay described here allows screening for anti-staphylococcal compounds that are not toxic to the host.

  17. Internalization of Staphylococcus aureus in Lymphocytes Induces Oxidative Stress and DNA Fragmentation: Possible Ameliorative Role of Nanoconjugated Vancomycin

    Directory of Open Access Journals (Sweden)

    Subhankari Prasad Chakraborty

    2011-01-01

    Full Text Available Staphylococcus aureus is the most frequently isolated pathogen causing bloodstream infections, skin and soft tissue infections and pneumonia. Lymphocyte is an important immune cell. The aim of the present paper was to test the ameliorative role of nanoconjugated vancomycin against Vancomycin-sensitive Staphylococcus aureus (VSSA and vancomycin-resistant Staphylococcus aureus (VRSA infection-induced oxidative stress in lymphocytes. VSSA and VRSA infections were developed in Swiss mice by intraperitoneal injection of 5×106 CFU/mL bacterial solutions. Nanoconjugated vancomycin was adminstrated to VSSA- and VRSA-infected mice at its effective dose for 10 days. Vancomycin was adminstrated to VSSA- and VRSA-infected mice at a similar dose, respectively, for 10 days. Vancomycin and nanoconjugated vancomycin were adminstrated to normal mice at their effective doses for 10 days. The result of this study reveals that in vivo VSSA and VRSA infection significantly increases the level of lipid peroxidation, protein oxidation, oxidized glutathione level, nitrite generation, nitrite release, and DNA damage and decreases the level of reduced glutathione, antioxidant enzyme status, and glutathione-dependent enzymes as compared to control group, which were increased or decreased significantly near to normal in nanoconjugated vancomycin-treated group. These findings suggest the potential use and beneficial role of nanoconjugated vancomycin against VSSA and VRSA infection-induced oxidative stress in lymphocytes.

  18. Clinical failure of vancomycin treatment of Staphylococcus aureus infection in a tertiary care hospital in southern Brazil

    Directory of Open Access Journals (Sweden)

    Larissa Lutz

    Full Text Available We describe a case of clinical failure of vancomycin treatment of Staphylococcus aureus infection and the laboratory characteristics of the organism in a tertiary referral university hospital in southern Brazil. An 11-month-old male patient presented with pneumonia and S. aureus was isolated from his respiratory tract. Initial treatment with oxacillin and gentamicin was ineffective. Vancomycin was added to the regimen as the patient worsened, but after the 30th day of vancomycin treatment S. aureus was isolated from the blood. This isolate had a minimum inhibitory concentration (MIC for vancomycin of 4 µg/mL. After pre-incubation with vancomycin the isolate displayed an increase in the expression of vancomycin resistance and colonies grew in the presence of up to 12 µg/mL vancomycin. Based on these results, and considering that the patient had not responded to vancomycin, the isolate was considered to be S. aureus heteroresistant to vancomycin (SAHV. The SAHV proved to be similar, based on DNA macrorestriction analysis, to methicillin resistant S. aureus (MRSA isolates from other patients in the hospital who had responded to vancomycin treatment. Our findings underline the need to improve methods in the clinical laboratory to detect the emergence of S. aureus clinically resistant to vancomycin . The fact that the isolate emerged in the blood 30 days after vancomycin treatment was initiated suggests that the organism was originally an MRSA that had acquired the ability to circumvent the mechanism of action of vancomycin.

  19. Antimicrobial susceptibility pattern of nasal Staphylococcus aureus among Dessie Referral Hospital health care workers, Dessie, Northeast Ethiopia.

    Science.gov (United States)

    Shibabaw, Agumas; Abebe, Tamrat; Mihret, Adane

    2014-08-01

    Staphylococcus aureus is a major pathogen in skin and soft tissue infections. Methicillin-resistant S. aureus (MRSA) is prevalent in most of the countries in which it is sought. MRSA is one of the important pathogens implicated in hospital-acquired infections. The main objectives of this study were to determine the antimicrobial susceptibility pattern of S. aureus isolates, the prevalence of MRSA, and the nasal carriage rate in healthy hospital staff members. A total of 118 health care workers (HCWs) were enrolled using a cross-sectional study design. Nasal swabs were collected and cultured on mannitol salt agar (MSA). The slide coagulase test was performed. Susceptibility testing was carried out on Mueller-Hinton agar using the modified Kirby-Bauer disk diffusion method with 10 antibiotics. Of the 118 HCWs, 34 had S. aureus and 15 had MRSA, with overall positivity rates of 28.8% and 12.7%, respectively. None of the S. aureus isolates were sensitive to penicillin. MRSA isolates were resistant to commonly available antibiotics. Only two (13.3%) of the nasal isolates were vancomycin-resistant. A high rate of nasal carriage and multidrug-resistant S. aureus was found in this study, indicating the need for standard infection control to prevent transmission in our health care setting. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  20. Performance of vancomycin and teicoplanin disk diffusion test in isogenic vancomycin non-susceptible Staphylococcus aureus.

    Science.gov (United States)

    Wongthong, Sujintana; Dutchanutouch, Karnjana; Namsaengkang, Viladda; Chanawong, Aroonwadee; Wilailuckana, Chotechana; Lulitanond, Aroonlug

    2015-02-19

    Detection of heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) is currently problematic. Although the population analysis profile with area under the curve (PAP-AUC) is the gold standard for detecting hVISA strains, this method is time consuming. This study aimed to induce vancomycin non-susceptible Staphylococcus aureus isolates in methicillin-resistant S. aureus (MRSA) and to determine the performance of the vancomycin and teicoplanin disk diffusion test for screening of induced and natural vancomycin non-susceptible isolates. Vancomycin resistance was induced in vitro in methicillin-resistant S. aureus by serial passage in media with increasing vancomycin concentrations. All test isolates were confirmed for their susceptibility to vancomycin by using a PAP-AUC method. The performance of the vancomycin and teicoplanin disk diffusion test for detecting both induced and natural hVISA/VISA isolates was analyzed using the MedCal program version 10.2.0. The induction test revealed that 42 of 78 MRSA isolates (53.8%) became hVISA and/or VISA. Using 10, 15, 20, 30 µg vancomycin disks and a 30 µg teicoplanin disk, the highest performance (88.9%) for hVISA/VISA detection (71.1%), sensitivity, 100% specificity, 100% positive predictive value, and 75% negative predictive value) was obtained when a 20 µg vancomycin disk was used at 1.0 McFarland inoculum for a 24-hour incubation. The results indicated that using a 20 µg vancomycin disk and bacterial inoculum of 1.0 McFarland is simple to perform and provides a primary result for hVISA/VISA screening within 24 hours.

  1. Characterization of SCCmec and spa types of methicillin-resistant Staphylococcus aureus isolates from health-care and community-acquired infections in Kerman, Iran.

    Science.gov (United States)

    Fasihi, Yaser; Kiaei, Somayeh; Kalantar-Neyestanaki, Davood

    2017-12-01

    Spread of methicillin-resistant Staphylococcus aureus (MRSA) isolates is a worldwide problem. Molecular typing is a useful tool to understand MRSA epidemiology. Herein, we determined vancomycin-resistant, SCCmec and spa types among MRSA isolates recovered from healthcare and community-acquired infections in Kerman, Iran. A total of 170 S. aureus isolates were collected from different patients who were admitted to affiliated hospitals of Kerman University of Medical science. MRSA and vancomycin-resistant S. aureus (VRSA) isolates were detected by phenotypic methods. Polymerase chain reaction (PCR) technique was used for detection of mecA, vanA and vanB genes. Staphylococcal cassette chromosomemec (SCCmec) and spa typing were used for molecular typing of among MRSA isolates. Overall, 53% of isolates were considered as MRSA. Two MRSA isolates were resistant to vancomycin and vanA was detected in only one of VRSA isolates. SCCmec type III belonged to spa types t030 and t459 which they were the dominant spa types among community-associated MRSA (CA-MRSA) and healthcare-acquired MRSA (HA-MRSA) isolates. Our findings showed that the SCCmec type I and III spread from hospital settings to community, although the SCCmec type IV spread from community to healthcare systems. We have also reported VRSA isolates from hospitalized patients, therefore, appropriate policies should be enforced in order to prevent the spread of antibiotic resistance isolates in hospitals settings. Copyright © 2017 Ministry of Health, Saudi Arabia. Published by Elsevier Ltd. All rights reserved.

  2. Occupational Exposure to Staphylococcus aureus and Enterococcus spp. among Spray Irrigation Workers Using Reclaimed Water

    Directory of Open Access Journals (Sweden)

    Rachel E. Rosenberg Goldstein

    2014-04-01

    Full Text Available As reclaimed water use expands, it is important to evaluate potential occupational health risks from exposure to this alternative water source. We compared odds of colonization with methicillin-resistant Staphylococcus aureus (MRSA, methicillin-susceptible S. aureus (MSSA, vancomycin-resistant enterococci (VRE, and vancomycin-susceptible enterococci (VSE between spray irrigation workers using reclaimed water and office worker controls. Nasal and dermal swabs from 19 spray irrigation workers and 24 office worker controls were collected and analyzed for MRSA, MSSA, VRE, and VSE. Isolates were confirmed using standard biochemical tests and polymerase chain reaction assays. Antimicrobial susceptibility testing was performed by Sensititre® microbroth dilution. Data were analyzed by two-sample proportion, chi-square, Fisher’s exact tests, and logistic regression. No MRSA or VRE were detected in any samples. MSSA was detected in 26% and 29% of spray irrigators and controls, respectively. VSE was detected in 11% and 0% of spray irrigation workers and controls, respectively. The adjusted odds of MSSA, multidrug-resistant MSSA, and either MSSA or VSE colonization were greater among spray irrigation workers, however results were not statistically significant. Future studies with larger sample sizes are needed to further evaluate this relationship.

  3. Occupational exposure to Staphylococcus aureus and Enterococcus spp. among spray irrigation workers using reclaimed water.

    Science.gov (United States)

    Rosenberg Goldstein, Rachel E; Micallef, Shirley A; Gibbs, Shawn G; He, Xin; George, Ashish; Sapkota, Amir; Joseph, Sam W; Sapkota, Amy R

    2014-04-17

    As reclaimed water use expands, it is important to evaluate potential occupational health risks from exposure to this alternative water source. We compared odds of colonization with methicillin-resistant Staphylococcus aureus (MRSA), methicillin-susceptible S. aureus (MSSA), vancomycin-resistant enterococci (VRE), and vancomycin-susceptible enterococci (VSE) between spray irrigation workers using reclaimed water and office worker controls. Nasal and dermal swabs from 19 spray irrigation workers and 24 office worker controls were collected and analyzed for MRSA, MSSA, VRE, and VSE. Isolates were confirmed using standard biochemical tests and polymerase chain reaction assays. Antimicrobial susceptibility testing was performed by Sensititre® microbroth dilution. Data were analyzed by two-sample proportion, chi-square, Fisher's exact tests, and logistic regression. No MRSA or VRE were detected in any samples. MSSA was detected in 26% and 29% of spray irrigators and controls, respectively. VSE was detected in 11% and 0% of spray irrigation workers and controls, respectively. The adjusted odds of MSSA, multidrug-resistant MSSA, and either MSSA or VSE colonization were greater among spray irrigation workers, however results were not statistically significant. Future studies with larger sample sizes are needed to further evaluate this relationship.

  4. Structural Basis for Streptogramin B Resistance in Staphylococcus aureus by Virginiamycin B Lyase

    Energy Technology Data Exchange (ETDEWEB)

    Korczynska,M.; Mukhtar, T.; Wright, G.; Berghuis, A.

    2007-01-01

    The streptogramin combination therapy of quinupristin-dalfopristin (Synercid) is used to treat infections caused by bacterial pathogens, such as methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecium. However, the effectiveness of this therapy is being compromised because of an increased incidence of streptogramin resistance. One of the clinically observed mechanisms of resistance is enzymatic inactivation of the type B streptogramins, such as quinupristin, by a streptogramin B lyase, i.e., virginiamycin B lyase (Vgb). The enzyme catalyzes the linearization of the cyclic antibiotic via a cleavage that requires a divalent metal ion. Here, we present crystal structures of Vgb from S. aureus in its apoenzyme form and in complex with quinupristin and Mg{sup 2+} at 1.65- and 2.8-{angstrom} resolution, respectively. The fold of the enzyme is that of a seven-bladed {beta}-propeller, although the sequence reveals no similarity to other known members of this structural family. Quinupristin binds to a large depression on the surface of the enzyme, where it predominantly forms van der Waals interactions. Validated by site-directed mutagenesis studies, a reaction mechanism is proposed in which the initial abstraction of a proton is facilitated by a Mg{sup 2+}-linked conjugated system. Analysis of the Vgb-quinupristin structure and comparison with the complex between quinupristin and its natural target, the 50S ribosomal subunit, reveals features that can be exploited for developing streptogramins that are impervious to Vgb-mediated resistance.

  5. Nasal carriage of methicillin-resistant Staphylococcus aureus by ...

    African Journals Online (AJOL)

    Strains of Staphylococcus aureus were isolated from the anterior nares of healthy pupils and their antibiotic susceptibility patterns were determined. 116 isolates of Staphylococcus aureus (100%) were biochemically characterized as coagulase positive S. aureus. Susceptibility profile of the isolates revealed that 15(14.85%) ...

  6. The sensitivity status of community-acquired Staphylococcus aureus ...

    African Journals Online (AJOL)

    Community acquired Staphylococcus aureus was isolated from various infectious sites in two private laboratories in Kano-city, Nigeria. A total of 247 (11%) Staphylococcu aureus isolates were recovered from all infectious sites except cerebro-spinal fluid. The least Staphylococcus aureus isolates were found in urine ...

  7. Relationship and susceptibility profile of Staphylococcus aureus infection diabetic foot ulcers with Staphylococcus aureus nasal carriage.

    Science.gov (United States)

    Taha, Aza Bahadeen

    2013-03-01

    Staphylococcus aureus is the main cause of diabetic foot infection with the patient's endogenous flora as the principal source. Nasal carriage of S. aureus has been identified as an important risk factor for the acquisition of diabetic foot infections. The study assessment the associations of S. aureus with methicillin resistant S. aureus were isolation from diabetic foot infection and nasal carriage of the same patients and their antibiotic susceptibility profile. Diagnosis of S. aureus and methicillin resistant S. aureus were carried out by using standard procedures. Antibiotic sensitivity profiles were determent by breakpoint dilution method. Out of 222 S. aureus isolation, 139 (62.61%) were isolated from the diabetic foot and 83 (37.39%) from the nasal carriage. Seventy one (30.87%) of the patients were S. aureus infection diabetic foot with nasal carriage. Among diabetic foot infection and nasal carriage patients, 40.85% of S. aureus were considered as methicillin resistant S. aureus. Rifampicin (96.40%) and Levofloxacin (91.44%) were active against S. aureus. Patients at strong risk for methicillin resistant S. aureus nasal carriage and subsequent diabetic foot infection with high resistance to antibiotics. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Mechanisms of Gentamicin Resistance in Staphylococcus aureus

    Science.gov (United States)

    Dowding, J. E.

    1977-01-01

    Three clinical isolates of Staphylococcus aureus resistant to gentamicin and other aminoglycosides have been examined for antibiotic modifying enzymes. The strains contain a number of these enzymes, most of them similar to those commonly found in aminoglycoside-resistant gram-negative strains. All three strains (and a transductant derived from one of them) contain two enzymes mediating gentamicin resistance, an aminoglycoside 6′-N-acetyltransferase and a novel enzyme, gentamicin phosphotransferase. PMID:836013

  9. Staphylococcus lugdunensis, a serious pathogen in periprosthetic joint infections: comparison to Staphylococcus aureus and Staphylococcus epidermidis

    Directory of Open Access Journals (Sweden)

    J. Lourtet-Hascoët

    2016-10-01

    Conclusion: S. lugdunensis is an emerging pathogen with a pathogenicity quite similar to that of S. aureus. This coagulase-negative Staphylococcus must be identified precisely in PJI, in order to select the appropriate surgical treatment and antibiotics .

  10. [Change in drug resistance of Staphylococcus aureus].

    Science.gov (United States)

    Lin, Yan; Liu, Yan; Luo, Yan-Ping; Liu, Chang-Ting

    2013-11-01

    To analyze the change in drug resistance of Staphylococcus aureus (SAU) in the PLA general hospital from January 2008 to December 2012, and to provide solid evidence to support the rational use of antibiotics for clinical applications. The SAU strains isolated from clinical samples in the hospital were collected and subjected to the Kirby-Bauer disk diffusion test. The results were assessed based on the 2002 American National Committee for Clinical Laboratory Standards (NCCLS) guidelines. SAU strains were mainly isolated from sputum, urine, blood and wound excreta and distributed in penology, neurology wards, orthopedics and surgery ICU wards. Except for glycopeptide drugs, methicillin-resistant Staphylococcus aureus (MRSA) had a higher drug resistance rate than those of the other drugs and had significantly more resistance than methicillin-sensitive Staphylococcus aureus (MSSA) (P resistance, we discovered a gradual increase in drug resistance to fourteen test drugs during the last five years. Drug resistance rate of SAU stayed at a higher level over the last five years; moreover, the detection ratio of MRSA keeps rising year by year. It is crucial for physicians to use antibiotics rationally and monitor the change in drug resistance in a dynamic way.

  11. Silkworm Apolipophorin Protein Inhibits Staphylococcus aureus Virulence*

    Science.gov (United States)

    Hanada, Yuichi; Sekimizu, Kazuhisa; Kaito, Chikara

    2011-01-01

    Silkworm hemolymph inhibits hemolysin production by Staphylococcus aureus. We purified a factor in the silkworm hemolymph responsible for this inhibitory activity. The final fraction with the greatest specific activity contained 220- and 74-kDa proteins. Determination of the N-terminal amino acid sequence revealed that the 220- and 74-kDa proteins were apolipophorin I and apolipophorin II, respectively, indicating that the factor was apolipophorin (ApoLp). The purified ApoLp fraction showed decreased expression of S. aureus hla encoding α-hemolysin, hlb encoding β-hemolysin, saeRS, and RNAIII, which activate the expression of these hemolysin genes. Injection of an anti-ApoLp antibody into the hemolymph increased the sensitivity of silkworms to the lethal effect of S. aureus. Hog gastric mucin, a mammalian homologue of ApoLp, decreased the expression of S. aureus hla and hlb. These findings suggest that ApoLp in the silkworm hemolymph inhibits S. aureus virulence and contributes to defense against S. aureus infection and that its activity is conserved in mammalian mucin. PMID:21937431

  12. Staphylococcus aureus pathogenesis in diverse host environments

    Science.gov (United States)

    Balasubramanian, Divya; Harper, Lamia; Shopsin, Bo; Torres, Victor J.

    2017-01-01

    Abstract Staphylococcus aureus is an eminent human pathogen that can colonize the human host and cause severe life-threatening illnesses. This bacterium can reside in and infect a wide range of host tissues, ranging from superficial surfaces like the skin to deeper tissues such as in the gastrointestinal tract, heart and bones. Due to its multifaceted lifestyle, S. aureus uses complex regulatory networks to sense diverse signals that enable it to adapt to different environments and modulate virulence. In this minireview, we explore well-characterized environmental and host cues that S. aureus responds to and describe how this pathogen modulates virulence in response to these signals. Lastly, we highlight therapeutic approaches undertaken by several groups to inhibit both signaling and the cognate regulators that sense and transmit these signals downstream. PMID:28104617

  13. Evolution of methicillin-resistant Staphylococcus aureus towards increasing resistance

    DEFF Research Database (Denmark)

    Strommenger, Birgit; Bartels, Mette Damkjær; Kurt, Kevin

    2014-01-01

    To elucidate the evolutionary history of Staphylococcus aureus clonal complex (CC) 8, which encompasses several globally distributed epidemic lineages, including hospital-associated methicillin-resistant S. aureus (MRSA) and the highly prevalent community-associated MRSA clone USA300....

  14. Mode of action of Buddleja cordata verbascoside against Staphylococcus aureus.

    Science.gov (United States)

    Avila, J G; de Liverant, J G; Martínez, A; Martínez, G; Muñoz, J L; Arciniegas, A; Romo de Vivar, A

    1999-07-01

    We evaluate the mode of action of verbascoside obtained from Buddleja cordata against Staphylococcus aureus by killing kinetics and incorporation of precursors methods. Verbascoside induced lethal effect on S. aureus, by affecting protein synthesis and inhibiting leucine incorporation.

  15. Prevalence of infective endocarditis in patients with Staphylococcus aureus bacteraemia

    DEFF Research Database (Denmark)

    Rasmussen, Rasmus V; Høst, Ulla; Arpi, Magnus

    2011-01-01

    Aims Staphylococcus aureus infective endocarditis (IE) is a critical medical condition associated with a high morbidity and mortality. In the present study, we prospectively evaluated the importance of screening with echocardiography in an unselected S. aureus bacteraemia (SAB) population. Methods...

  16. Prevalence of methicillin resistant Staphylococcus aureus [MRSA] colonization or carriage among health-care workers.

    Science.gov (United States)

    Pathare, Nirmal A; Asogan, Harshini; Tejani, Sara; Al Mahruqi, Gaitha; Al Fakhri, Salma; Zafarulla, Roshna; Pathare, Anil V

    2016-01-01

    In Oman, the prevalence of health care associated methicillin resistant Staphylococcus aureus [HA-MRSA] is unknown. Therefore, to estimate the prevalence of HA-MRSA, we collected nasal swabs and swabs from cell phones on sterile polyester swabs and immediately inoculated on the mannitol salt agar containing oxacillin from medical students and hospital health care providers. Antibiotic susceptibility testing of the isolates was then performed using the Kirby Bauer's disc diffusion method. Additionally, a brief survey questionnaire was used to acquire demographic data. Amongst the 311 participants enrolled, nasal colonization with HA-MRSA was found in 47 individuals (15.1%, 95% confidence interval [CI]=11.1%, 19.1%). HA-MRSA was also isolated from the cell phone surfaces in 28 participants (9.0%, 95% CI=8.6%, 9.3%). 5 participants (1.6%) showed positive results both from their nasal swabs and from their cell phones. Antibiotic resistance to erythromycin [48%] and clindamycin [29%] was relatively high. 9.3% HA-MRSA isolates were vancomycin resistant [6.6% nasal carriage]. There was no statistically significant correlation between HA-MRSA isolates and the demographic characteristics or the risk factors namely gender, underlying co-morbidities like diabetes, hypertension, skin/soft tissue infections, skin ulcers/wounds, recent exposure to antibiotics, or hospital visits (p>0.05, Chi-square test). Copyright © 2015 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

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

    DEFF Research Database (Denmark)

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

    2009-01-01

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

  18. Daptomycin antimicrobial activity tested against methicillin-resistant staphylococci and vancomycin-resistant enterococci isolated in European medical centers (2005

    Directory of Open Access Journals (Sweden)

    Watters Amy A

    2007-04-01

    Full Text Available Abstract Background Daptomycin is a cyclic lipopeptide with potent activity and broad spectrum against Gram-positive bacteria currently used for the treatment of complicated skin and skin structure infections and bacteremia, including right sided endocarditis. We evaluated the in vitro activity of this compound and selected comparator agents tested against clinical strains of staphylococci and enterococci collected in European medical centers in 2005. Methods A total of 4,640 strains from 23 medical centers located in 10 European countries, Turkey and Israel (SENTRY Program platform were tested for susceptibility by reference broth microdilution methods according to Clinical and Laboratory Standards Institute guidelines and interpretative criteria. Mueller-Hinton broth was supplemented to 50 mg/L Ca++ for testing daptomycin. Results for oxacillin (methicillin-resistant staphylococci and vancomycin-resistant enterococci were analyzed separately. Results Oxacillin resistance rates among Staphylococcus aureus varied from 2.1% in Sweden to 42.5% in the United Kingdom (UK and 54.7% in Ireland (29.1% overall, while vancomycin resistance rates varied from 0.0% in France, Sweden and Switzerland to 66.7% in the UK and 71.4% in Ireland among Enterococcus faecium (17.9% overall. All S. aureus strains were inhibited at daptomycin MIC of 1 mg/L (MIC50/90, 0.25/0.5 mg/L; 100.0% susceptible and only one coagulase-negative staphylococci strain (0.1% showed an elevated (>1 mg/L daptomycin MIC value (4 mg/L. Among E. faecalis (MIC50/90, 0.5/1 mg/L; 100% susceptible the highest daptomycin MIC value was 2 mg/L; while among E. faecium (MIC50/90, 2/4 mg/L; 100% susceptible the highest MIC result was 4 mg/L. Conclusion Daptomycin showed excellent in vitro activity against staphylococci and enterococci collected in European medical centers in 2005 and resistance to oxacillin, vancomycin or quinupristin/dalfopristin did not compromise its activity overall against these

  19. Meticillin-resistant Staphylococcus aureus (MRSA)

    DEFF Research Database (Denmark)

    Stefani, Stefania; Chung, Doo Ryeon; Lindsay, Jodi A

    2012-01-01

    decisions with regard to harmonisation of typing methods. A stratified, three-level organisation of testing laboratories was proposed: local; regional; and national. The functions of, and testing methodology used by, each laboratory were defined. The group consensus was to recommend spa and staphylococcal......This article reviews recent findings on the global epidemiology of healthcare-acquired/associated (HA), community-acquired/associated (CA) and livestock-associated (LA) meticillin-resistant Staphylococcus aureus (MRSA) and aims to reach a consensus regarding the harmonisation of typing methods...... health. Continuous efforts to understand the changing epidemiology of S. aureus infection in humans and animals are therefore necessary, not only for appropriate antimicrobial treatment and effective infection control but also to monitor the evolution of the species. The group made several consensus...

  20. Crystal structure of Staphylococcus aureus Cas9

    OpenAIRE

    Nishimasu, Hiroshi; Cong, Le; Yan, Winston X.; Ran, F. Ann; Zetsche, Bernd; Li, Yinqing; Kurabayashi, Arisa; Ishitani, Ryuichiro; Zhang, Feng; Nureki, Osamu

    2015-01-01

    The RNA-guided DNA endonuclease Cas9 cleaves double-stranded DNA targets with a protospacer adjacent motif (PAM) and complementarity to the guide RNA. Recently, we harnessed Staphylococcus aureus Cas9 (SaCas9), which is significantly smaller than Streptococcus pyogenes Cas9 (SpCas9), to facilitate efficient in vivo genome editing. Here, we report the crystal structures of SaCas9 in complex with a single guide RNA (sgRNA) and its double-stranded DNA targets, containing the 5′-TTGAAT-3′ PAM and...

  1. Modified PAP method to detect heteroresistance to vancomycin among methicillin resistant Staphylococcus aureus isolates at a tertiary care hospital

    Directory of Open Access Journals (Sweden)

    Iyer R

    2008-01-01

    Full Text Available This study was an attempt at developing, establishing, validating and comparing the modified PAP method for detection of hetero-vancomycin resistant Staphylococcus aureus (h-VRSA with the routine antimicrobial susceptibility testing (using the BSAC standardized disc diffusion method, minimum inhibitory concentrations of vancomycin using standard E-test methodology and the Hiramatsu′s screening method. A total of 50 methicillin resistant Staphylococcus aureus obtained from various clinical specimens, along with the Mu 3 and Mu 50 strains as controls, were studied. No VRSA isolates were obtained. However, four of the test strains were positive by the Hiramatsu′s screening method, of which only one isolate could be confirmed by the modified PAP analysis method. This isolate was a coloniser from the drain fluid of a liver transplant recipient. The sensitivity, specificity, positive predictive value and the overall efficiency of the Hiramatsu′s screening method with the modified PAP analysis as the gold standard were found to be 100, 93.8, 25 and 94%, respectively. It is very essential for clinical laboratories to screen for h-VRSA, given the increasing use of glycopeptide antibiotics in therapy and the potential for failed therapy in patients infected with these strains.

  2. Staphylococcus aureus bacteraemia in children: a formidable foe

    African Journals Online (AJOL)

    Staphylococcus aureus remains one of the most common causes of bacteraemia in children. In order to evade and overcome the immune responses of its host and any antimicrobial therapies aimed at destroying it, this organism, through various mechanisms, continues to evolve. Staphylococcus aureus bacteraemia is a ...

  3. Prevalence of Methicillin-Resistant Staphylococcus aureus among ...

    African Journals Online (AJOL)

    Purpose: To determine the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in apparently healthy ... Keywords: Methicillin-resistant Staphylococcus aureus, Nasal swabs, Multidrug resistance, Rational chemotherapy .... Figure 2: Antibiotic resistance profile of the MRSA isolates. Key: AM-amoxicillin ...

  4. Prevalence of Staphylococcus aureus and methicillin resistant Staphylococcus aureus (MRSA) in the oral cavity.

    Science.gov (United States)

    Koukos, Georgios; Sakellari, Dimitra; Arsenakis, Minas; Tsalikis, Lazaros; Slini, Theodora; Konstantinidis, Antonios

    2015-09-01

    To assess the prevalence of Staphylococcus aureus and methicillin resistant Staphylococcus aureus (MRSA) in plaque and tongue samples from systemically healthy subjects with periodontal health, gingivitis or chronic periodontitis. After screening 720 potentially eligible subjects, 154 systemically healthy participants were ultimately enrolled in the current study. Subgingival samples were taken from the first molars and the tongue and analyzed for the presence of S. aureus and MRSA by polymerase chain reaction (PCR), using primers and conditions previously described in the literature. In addition, samples were taken from deep periodontal pockets of chronic periodontitis patients. Statistical analysis was performed by applying non-parametric tests (Kruskal-Wallis for clinical parameters, and z-test with Bonferroni corrections for distributions of assessed parameters). All comparisons were set at the 0.05 significance level. S. aureus was detected in 18% of all participants and in 10% of the samples tested. No significant differences were found in its distribution among the three investigated groups (z-test for proportions with Bonferroni corrections, p>0.05). The mecA gene was not present in any of the S. aureus found. S. aureus can be found in the oral environment regardless of the periodontal conditions and therefore should be considered as a member of the transient flora not participating in periodontal pathology. Subgingival sites and tongue surfaces seem to be an unusual habitat of MRSA. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Antibiotic resistant Staphylococcus aureus in Abia State of Nigeria ...

    African Journals Online (AJOL)

    A total of 70 ear and nasal swab samples collected from 35 persons, 16-hospital population and 19 non-hospital population was examined for presence of Staphylococcus aureus. Eighty percent of the population studied were found to be carriers of S. aureus. Of the 28 positive cases, 35.7% were carriers of S. aureus. in ...

  6. Immunological role of nasal staphylococcus aureus carriage in ...

    African Journals Online (AJOL)

    raoul

    2008-10-30

    Oct 30, 2008 ... Nasal carriage of staphylococcus aureus (S. aureus) exerts immunomodulatory effects in patients with atopic dermatitis and it may contribute to airway inflammation and allergic response in patients with allergic rhinitis. We investigated the frequency of nasal S. aureus carriage in patients with perennial ...

  7. Immunopathogenesis of Staphylococcus aureus pulmonary infection

    Science.gov (United States)

    Parker, Dane; Prince, Alice

    2013-01-01

    Staphylococcus aureus is a common human pathogen highly evolved as both a component of the commensal flora and as a major cause of invasive infection. Severe respiratory infection due to staphylococci has been increasing due to the prevalence of more virulent USA300 CA-MRSA strains in the general population. The ability of S. aureus to adapt to the milieu of the respiratory tract has facilitated its emergence as a respiratory pathogen. Its metabolic versatility, the ability to scavenge iron, coordinate gene expression, and the horizontal acquisition of useful genetic elements have all contributed to its success as a component of the respiratory flora, in hospitalized patients, as a complication of influenza and in normal hosts. The expression of surface adhesins facilitates its persistence in the airways. In addition, the highly sophisticated interactions of the multiple S. aureus virulence factors, particularly the α-hemolysin and protein A, with diverse immune effectors in the lung such as ADAM10, TNFR1, EGFR, immunoglobulin, and complement all contribute to the pathogenesis of staphylococcal pneumonia. PMID:22037948

  8. Staphylococcus lugdunensis, a serious pathogen in periprosthetic joint infections: comparison to Staphylococcus aureus and Staphylococcus epidermidis.

    Science.gov (United States)

    Lourtet-Hascoët, J; Bicart-See, A; Félicé, M P; Giordano, G; Bonnet, E

    2016-10-01

    The aim of this study was to assess the characteristics of periprosthetic joint infection (PJI) due to Staphylococcus lugdunensis and to compare these to the characteristics of PJI due to Staphylococcus aureus and Staphylococcus epidermidis. A retrospective multicentre study including all consecutive cases of S. lugdunensis PJI (2000-2014) was performed. Eighty-eight cases of staphylococcal PJI were recorded: 28 due to S. lugdunensis, 30 to S. aureus, and 30 to S. epidermidis, as identified by Vitek 2 or API Staph (bioMérieux). Clinical symptoms were more often reported in the S. lugdunensis group, and the median delay between surgery and infection was shorter for the S. lugdunensis group than for the S. aureus and S. epidermidis groups. Regarding antibiotic susceptibility, the S. lugdunensis strains were susceptible to antibiotics and 61% of the patients could be treated with levofloxacin + rifampicin. The outcome of the PJI was favourable for 89% of patients with S. lugdunensis, 83% with S. aureus, and 97% with S. epidermidis. S. lugdunensis is an emerging pathogen with a pathogenicity quite similar to that of S. aureus. This coagulase-negative Staphylococcus must be identified precisely in PJI, in order to select the appropriate surgical treatment and antibiotics . Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  9. [Staphylococcus aureus in bulk milk samples].

    Science.gov (United States)

    Benda, P; Vyletĕlová, M

    1995-07-01

    In the years 1993-1994 the occurrence of Staphylococcus aureus was investigated in bulk milk samples in the area where a Baby Food Factory at Zábreh in Moravia is located, and in Bruntál, Zlín and Policka districts. Evaluation of the results was based on ECC Directive 92/46, while the dynamics of S. aureus presence was followed for the whole period of observation as well as in the particular seasons. A total of 4,485 samples was processed. Out of these, 50.7% contained less than 100 CFU/ml of S. aureus, 41.4% contained 100-500 CFU/ml, 6.73% 500-2,000 CFU/ml and 1.14% contained more than 2,000 CFU/ml (Fig. 1). The samples were divided into three categories: private new-established farms, cooperative and State-owned enterprises in the area of the Zábĕh Factory and others (Zlín, Bruntál and Policka districts). There were highly significant differences in the content of staphylococci (P = 0.01%) between the three categories of samples. Ninety-eight percent of samples from private farms, 96% samples from the Zábreh Factory area and 85% of the other samples comply with the regulation EEC 92/64 (Tab. I) for raw cow's milk for the manufacture of products "made with raw milk" whose manufacturing process does not involve any heat treatment (Fig. 2). The occurrence of S. aureus in the Zábreh Factory area shows an expressive seasonal dynamics (P = 0.005%) with maximum values in winter months (December-March) and minimum values in summer months (July-October)-Fig. 3. The same relationship can be seen on more extensive data files for the particular producers (Fig. 4).(ABSTRACT TRUNCATED AT 250 WORDS)

  10. Disruption of Methicillin-resistant Staphylococcus aureus Biofilms with Enzymatic Therapeutics

    Science.gov (United States)

    2015-04-29

    NAVAL MEDICAL RESEARCH UNIT SAN ANTONIO Disruption of Methicillin-resistant Staphylococcus aureus Biofilms with Enzymatic...Methicillin-resistant Staphylococcus aureus MSSA Methicillin-sensitive Staphylococcus aureus OD Optical density PBS Phosphate-buffered saline SEM... Staphylococcus aureus biofilm model that mimics wound-like conditions and employ this model to evaluate the anti-biofilm activity of four enzymatic compounds

  11. Total synthesis of (±)-naphthacemycin A9, possessing both antibacterial activity against methicillin-resistant Staphylococcus aureus and circumventing effect of β-lactam resistance.

    Science.gov (United States)

    Hirose, Tomoyasu; Kojima, Yasuhiro; Matsui, Hidehito; Hanaki, Hideaki; Iwatsuki, Masato; Shiomi, Kazuro; Ōmura, Satoshi; Sunazuka, Toshiaki

    2017-05-01

    The total synthesis of KB-3346-5A 9 , named naphthacemycin A 9 , has been accomplished by combining the Dötz reaction and Suzuki-Miyaura cross coupling as well as employing Friedel-Crafts reaction with dienone-phenol rearrangement as key steps. We also describe the preparation of the simplified tetarimycin A and naphthacemycin A analogs as a model study, which coincidentally reveal unique properties of naturally occurring naphthacene-5,6,11(12H)-trione framework. The synthesized compounds were evaluated for antibacterial activity against methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus (VRE) to elucidate their structure-activity relationships (SARs), the results of which agreed with a previously reported preliminary SAR study of tetarimycin A.

  12. Vancomycin-resistant enterococcal infections in Korea.

    Science.gov (United States)

    Kim, J M; Song, Y G

    1998-12-01

    Enterococci recently became the second-to-third most commonly isolated organism from nosocomial infections. Enterococci are intrinsically more resistant to many antimicrobial agents and often show acquired resistance to many antimicrobial agents including high-level aminoglycosides. With the increased use of vancomycin, vancomycin-resistant enterococci (VRE) has become an important nosocomial pathogen. In Korea, the proportion of VRE among all enterococcal of VRE is no longer low in some settings and recent observations of a sudden increase of VRE isolation in several hospitals in Korea suggests that VRE infection may become a serious problem in the near future. The most important considerations are that vancomycin-resistant genes may spread to other highly virulent genera, such as MRSA, and that there are no approved and convincingly effective antibiotics for the treatment of VRE. Therefore, current efforts have concentrated on limiting the spread of these organisms within the hospital environment. Prudent use of antimicrobial agents and strict adherence to preventive measures such as aggressive communication, education, and infection control practices are essential to control the spread of this organism. However, hospital infection control protocols and the laboratory support they require are costly in terms of space and supplies, as well as in personnel resources. These factors add further pressure to already stretched hospital budgets. Nevertheless, policies or programs defining and managing VRE infection or colonization should be established and now is the time to enforce an overall management strategy against VRE.

  13. A porcine model of haematogenous brain infectionwith staphylococcus aureus

    DEFF Research Database (Denmark)

    Astrup, Lærke Boye; Agerholm, Jørgen Steen; Nielsen, Ole Lerberg

    2012-01-01

    A PORCINE MODEL OF HAEMATOGENOUS BRAIN INFECTION WITH STAPHYLOCOCCUS AUREUS Astrup Lærke1, Agerholm Jørgen1, Nielsen Ole1, Jensen Henrik1, Leifsson Páll1, Iburg Tine2. 1: Faculty of Health and Medical Sciences, University of Copenhagen, Denmark boye@life.ku.dk 2: National Veterinary Institute......, Uppsala, Sweden Introduction Staphylococcus aureus (S.aureus) is a common cause of sepsis and brain abscesses in man and a frequent cause of porcine pyaemia. Here we present a porcine model of haematogenous S. aureus-induced brain infection. Materials and Methods Four pigs had two intravenous catheters...

  14. Staphylococcus aureus: resistance pattern and risk factors

    Directory of Open Access Journals (Sweden)

    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.

  15. Curcumin Reverse Methicillin Resistance in Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Su-Hyun Mun

    2014-11-01

    Full Text Available Curcumin, a natural polyphenolic flavonoid extracted from the rhizome of Curcuma longa L., was shown to possess superior potency to resensitize methicillin-resistant Staphylococcus aureus (MRSA to antibiotics. Previous studies have shown the synergistic activity of curcumin with β-lactam and quinolone antibiotics. Further, to understand the anti-MRSA mechanism of curcumin, we investigated the potentiated effect of curcumin by its interaction in diverse conditions. The mechanism of anti-MRSA action of curcumin was analyzed by the viability assay in the presence of detergents, ATPase inhibitors and peptidoglycan (PGN from S. aureus, and the PBP2a protein level was analyzed by western blotting. The morphological changes in the curcumin-treated MRSA strains were investigated by transmission electron microscopy (TEM. We analyzed increased susceptibility to MRSA isolates in the presence of curcumin. The optical densities at 600 nm (OD600 of the suspensions treated with the combinations of curcumin with triton X-100 and Tris were reduced to 63% and 59%, respectively, compared to curcumin without treatment. N,N'-dicyclohexylcarbodiimide (DCCD and sodium azide (NaN3 were reduced to 94% and 55%, respectively. When peptidoglycan (PGN from S. aureus was combined with curcumin, PGN (0–125 μg/mL gradually blocked the antibacterial activity of curcumin (125 μg/mL; however, at a concentration of 125 µg/mL PGN, it did not completely block curcumin. Curcumin has a significant effect on the protein level of PBP2a. The TEM images of MRSA showed damage of the cell wall, disruption of the cytoplasmic contents, broken cell membrane and cell lysis after the treatment of curcumin. These data indicate a remarkable antibacterial effect of curcumin, with membrane permeability enhancers and ATPase inhibitors, and curcumin did not directly bind to PGN on the cell wall. Further, the antimicrobial action of curcumin involved in the PBP2a-mediated resistance mechanism was

  16. Cytoplasmic peptidoglycan intermediate levels in Staphylococcus aureus.

    Science.gov (United States)

    Vemula, Harika; Ayon, Navid J; Gutheil, William G

    2016-02-01

    Intracellular cytoplasmic peptidoglycan (PG) intermediate levels were determined in Staphylococcus aureus during log-phase growth in enriched media. Levels of UDP-linked intermediates were quantitatively determined using ion pairing LC-MS/MS in negative mode, and amine intermediates were quantitatively determined stereospecifically as their Marfey's reagent derivatives in positive mode. Levels of UDP-linked intermediates in S. aureus varied from 1.4 μM for UDP-GlcNAc-Enolpyruvyate to 1200 μM for UDP-MurNAc. Levels of amine intermediates (L-Ala, D-Ala, D-Ala-D-Ala, L-Glu, D-Glu, and L-Lys) varied over a range of from 860 μM for D-Ala-D-Ala to 30-260 mM for the others. Total PG was determined from the D-Glu content of isolated PG, and used to estimate the rate of PG synthesis (in terms of cytoplasmic metabolite flux) as 690 μM/min. The total UDP-linked intermediates pool (2490 μM) is therefore sufficient to sustain growth for 3.6 min. Comparison of UDP-linked metabolite levels with published pathway enzyme characteristics demonstrates that enzymes on the UDP-branch range from >80% saturation for MurA, Z, and C, to <5% saturation for MurB. Metabolite levels were compared with literature values for Escherichia coli, with the major difference in UDP-intermediates being the level of UDP-MurNAc, which was high in S. aureus (1200 μM) and low in E. coli (45 μM). Copyright © 2015 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

  17. The Pre - Eminence of Staphylococcus Aureus as The Causative ...

    African Journals Online (AJOL)

    Specimens were collected for culture and sensitivity before commencement of antibiotic therapy. The major isolated organism was Staphylococcus aureus. Others were Pseudomonas aeruginosa, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris Proteus rettgerri, Alkaligenes faecalis, Acinetobacter calcoaceticus ...

  18. A Closer Look at the Transcriptome of Staphylococcus aureus

    NARCIS (Netherlands)

    Smits, N.J.P.

    2012-01-01

    Tight regulation of genes upon changing environments is important in establishing and maintaining infections by pathogens. In Staphylococcus aureus, gene expression and particularly controlled expression of various groups of genes dependent on growth and environmental conditions is essential for

  19. Multilocus sequence typing of Staphylococcus aureus with DNA array technology

    NARCIS (Netherlands)

    W.B. van Leeuwen (Willem); C. Jay (Corinne); S.V. Snijders (Susan); N. Durin (Nathalia); B. Lacroix (Bruno); H.A. Verbrugh (Henri); M.C. Enright (Mark); A. Troesch (Alain); A.F. van Belkum (Alex)

    2003-01-01

    textabstractA newly developed oligonucleotide array suited for multilocus sequence typing (MLST) of Staphylococcus aureus strains was analyzed with two strain collections in a two-center study. MLST allele identification for the first strain collection fully agreed with

  20. Sensibilité aux antibiotiques des souches de staphylococcus aureus ...

    African Journals Online (AJOL)

    Sensibilité aux antibiotiques des souches de staphylococcus aureus communautaires dans la région de Nouakchott (Mauritanie). Mohamed Lemine Ould Salem, Sidi Mohamed Ghaber, Sidi El Wafi Ould Baba, Mohamed Mahmoud Ould Maouloud ...

  1. Host- and tissue-specific pathogenic traits of Staphylococcus aureus.

    NARCIS (Netherlands)

    W.B. van Leeuwen (Willem); D.C. Melles (Damian); A. Alaidan (Alwaleed); M. Al-Ahdal (Mohammed); H.A.M. Boelens (Hélène); S.V. Snijders (Susan); H.F.L. Wertheim (Heiman); E. van Duijkeren (Engeline); J.K. Peeters (Justine); P.J. van der Spek (Peter); R.F.J. Gorkink (Raymond); G. Simons (Guus); H.A. Verbrugh (Henri); A.F. van Belkum (Alex)

    2005-01-01

    textabstractComparative genomics were used to assess genetic differences between Staphylococcus aureus strains derived from infected animals versus colonized or infected humans. A total of 77 veterinary isolates were genetically characterized by high-throughput amplified fragment length polymorphism

  2. Left-sided native valve Staphylococcus aureus endocarditis

    NARCIS (Netherlands)

    Slabbekoorn, M.; Horlings, H. M.; van der Meer, J. T. M.; Windhausen, A.; Van der Sloot, J. A. P.; Lagrand, W. K.

    2010-01-01

    Despite improved diagnostic tools and expanded treatment options, left-sided native valve endocarditis caused by Staphylococcus aureus infection remains a serious and destructive disease. The high morbidity and mortality, however, can be reduced by early recognition, correct diagnosis, and

  3. Improving Diagnosis and Treatment of Staphylococcus aureus Infections : Experimental Studies

    NARCIS (Netherlands)

    S. van den Berg (Sanne)

    2015-01-01

    markdownabstract__Abstract__ Staphylococcus aureus is an opportunistic pathogen that causes a variety of infections, ranging from mild skin infections like furuncles and impetigo, to severe, lifethreatening infections including endocarditis, osteomyelitis and pneumonia. Invasive infections are

  4. Prevalence and risk factors for Staphylococcus aureus and ...

    African Journals Online (AJOL)

    2015-09-05

    Sep 5, 2015 ... Materials and Methods: Nasal samples were taken from anterior nares ..... 3599 preoperative nasal cultures for a year and found 16.6% .... methicillin‑resistant and methicillin‑susceptible Staphylococcus aureus in nursing.

  5. Antibiotic sensitivity pattern of Staphylococcus aureus from clinical

    African Journals Online (AJOL)

    raoul

    2011-01-26

    Jan 26, 2011 ... Erythromycin, Chloramphenicol, Cotrimoxazole, Tetracycline, Penicillin, Ciprofloxacin, Ofloxacin, Levofloxacin, Ceftriaxone, Amoxycillin and vancomycin were 92.4% .... Kirmany N, Tuazon CV, Alling D. Carriage of Staphylococcus aureus among patients receiving allergy injections. Ann allergy. 1980;.

  6. Development of a heptaplex PCR assay for identification of Staphylococcus aureus and CoNS with simultaneous detection of virulence and antibiotic resistance genes.

    Science.gov (United States)

    Okolie, Charles Emeka; Wooldridge, Karl G; Turner, David P J; Cockayne, Alan; James, Richard

    2015-08-05

    Staphylococcal toxicity and antibiotic resistance (STAAR) have been menacing public health. Although vancomycin-resistant Staphylococcus aureus (VRSA) is currently not as widespread as methicillin-resistant S. aureus (MRSA), genome evolution of MRSA into VRSA, including strains engineered within the same patient under anti-staphylococcal therapy, may build up to future public health concern. To further complicate diagnosis, infection control and anti-microbial chemotherapy, non-sterile sites such as the nares and the skin could contain both S. aureus and coagulase-negative staphylococci (CoNS), either of which could harbour mecA the gene driving staphylococcal methicillin-resistance and required for MRSA-VRSA evolution. A new heptaplex PCR assay has been developed which simultaneously detects seven markers for: i) eubacteria (16S rRNA), ii) Staphylococcus genus (tuf), iii) Staphylococcus aureus (spa), iv) CoNS (cns), v) Panton-Valentine leukocidin (pvl), vi) methicillin resistance (mecA), and vii) vancomycin resistance (vanA). Following successful validation using 255 reference bacterial strains, applicability to analyse clinical samples was evaluated by direct amplification in spiked blood cultures (n = 89) which returned 100 % specificity, negative and positive predictive values. The new assay has LoD of 1.0x10(3) CFU/mL for the 16S rRNA marker and 1.0x10(4) CFU/mL for six other markers and completes cycling in less than one hour. The speed, sensitivity (100 %), NPV (100 %) and PPV (100 %) suggest the new heptaplex PCR assay could be easily integrated into a routine diagnostic microbiology workflow. Detection of the cns marker allows for unique identification of CoNS in mono-microbial and in poly-microbial samples containing mixtures of CoNS and S. aureus without recourse to the conventional elimination approach which is ambiguous. In addition to the SA-CoNS differential diagnostic essence of the new assay, inclusion of vanA primers will allow

  7. Prevalence of nasal portal of Staphylococcus aureus in disabled children.

    Directory of Open Access Journals (Sweden)

    Clotilde Molin

    2016-06-01

    Full Text Available Introduction: Colonization of the nasal mucosa by Staphylococcus aureus set a carrier state. Which is recognized as a potential source of infection and a high risk factor for subsequent invasive infections. The prevalence of nasal carriage of this germ in disabled children in Paraguay is not known, thus contributing to the knowledge of their frequency and evaluate the profile of sensitivity to common antimicrobials was conducted this study, from May to July 2015.  Objective: to determine the prevalence of Staphylococcus aureus nasal carriage and profile of antimicrobial resistance in disabled children. Materials and Methods: A descriptive cross-sectional study in which 80 nasal swabs of children, who attended the service laboratory of SENADIS (Secretaria Nacional por los Derechos Humanos de las Personas con Discapacidad. The identification and sensitivity of germ was accomplished by conventional testing.  Results: 80 pediatric patients, 46 boys and 34 girls. 18 isolates of Staphylococcus aureus were obtained, corresponding to a prevalence of 22,5%. Susceptibility testing indicated that 14 strains were MSSA (Methicillin – Sensitive Staphylococcus aureus and 4 RMSA ( Methicillin- resistant Staphylococcus aureus. Conclusion: The prevalence of Staphylococcus aureus in a population with its own characteristics provides valuable data for the epidemiology, reflecting the need for continued vigilance and take steps to reduce associated infections. The detection of RMAR evidences their progress; it is important to evaluate the empirical treatment to primary care.

  8. Threat of drug resistant Staphylococcus aureus to health in Nepal.

    Science.gov (United States)

    Ansari, Shamshul; Nepal, Hari Prasad; Gautam, Rajendra; Rayamajhi, Nabin; Shrestha, Sony; Upadhyay, Goma; Acharya, Anju; Chapagain, Moti Lal

    2014-03-22

    Staphylococcus aureus is the most commonly isolated organism from the different clinical samples in hospital. The emergence and dissemination of methicillin resistant Staphylococcus aureus (MRSA) and growing resistance to non-beta-lactam antibiotics is making treatment of infections due to this organism increasingly difficult. This study was conducted to determine the frequency of Staphylococcus aureus isolated from different clinical samples, rates of MRSA and full antibiotic susceptibility profiles. Clinical samples were cultured and Staphylococcus aureus was identified using standard microbiological methods recommended by the American Society for Microbiology (ASM). Methicillin resistance was confirmed using cefoxitin and oxacillin disks. Inducible clindamycin resistance was identified using D-zone test. From the processed samples, 306 isolates of Staphylococcus aureus were recovered. All the isolates were susceptible to vancomycin and teicoplanin. Methicillin resistance was observed in 43.1% of isolates while inducible clindamycin resistance in 12.4% of the isolates. The results of our study reveals that rates of resistance to commonly prescribed antibiotics in Staphylococcus aureus clinical isolates is high. In particular, rate of methicillin resistance is alarming, prompting concern on the rational use of antibiotics and vigilant laboratory-based surveillance of resistance rates in Nepal.

  9. Novel Structure of Enterococcus faecium-Originated ermB-Positive Tn1546-Like Element in Staphylococcus aureus.

    Science.gov (United States)

    Wan, Tsai-Wen; Hung, Wei-Chun; Tsai, Jui-Chang; Lin, Yu-Tzu; Lee, Hao; Hsueh, Po-Ren; Lee, Tai-Fen; Teng, Lee-Jene

    2016-10-01

    We determined the resistance determinants in 274 erythromycin-resistant methicillin-susceptible Staphylococcus aureus (MSSA) isolates during a 13-year period, 2000 to 2012. The resistance phenotypes, inducible macrolide-lincosamide-streptogramin (iMLS), constitutive MLS (cMLS), and macrolide-streptogramin (MS) resistance phenotypes, were examined by a double-disk diffusion D test. The ermB gene was more frequent (35%; 97/274) than ermC (27%; 75/274) or ermA (21%; 58/274). All 97 ermB-positive isolates harbored Tn551 and IS1216V The majority (89/97) of ermB-positive isolates displayed the cMLS phenotype and carried mobile element structure (MES)-like structures, which has been previously reported in sequence type 59 (ST59) methicillin-resistant S. aureus (MRSA). The remaining 8 ermB-carrying isolates, belonging to ST7 (n = 4), ST5 (n = 3), and ST59 (n = 1), were sasK intact and did not carry MES-like structures. Unlike a MES-like structure that was located on the chromosome, the ermB elements on sasK-intact isolates were located on plasmids by S1 nuclease pulsed-field gel electrophoresis (PFGE) analysis and conjugation tests. Sequence data for the ermB-containing region (14,566 bp) from ST59 NTUH_3874 revealed that the best match was a Tn1546-like element in plasmid pMCCL2 DNA (GenBank accession number AP009486) of Macrococcus caseolyticus Tn1546 is recognized as an enterococcal transposon and was known from the vancomycin resistance gene cluster in vancomycin-resistant Enterococcus (VRE). So far, acquisitions of Tn1546 in S. aureus have occurred in clonal complex 5 (CC5) MRSA, but not in MSSA. This is the first report that MSSA harbors an Enterococcus faecium-originated ermB-positive Tn1546-like element located on a plasmid. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  10. Beta Lactamase production by Staphylococcus aureus from children ...

    African Journals Online (AJOL)

    Isolates of Staphylococcus aureus from children aged 5 years and below with sporadic diarrhoea were tested for their ability to produce beta-lactamase enzyme. Of the 95 isolates tested 79 (83.2%) were beta-lactamase-producing strains. The study confirms that majority of clinical isolates of S. aureus from diarrhoeic ...

  11. Intercenter reproducibility of binary typing for Staphylococcus aureus

    NARCIS (Netherlands)

    van Leeuwen, Willem B.; Snoeijers, Sandor; van der Werken-Libregts, Christel; Tuip, Anita; van der Zee, Anneke; Egberink, Diane; de Proost, Monique; Bik, Elisabeth; Lunter, Bjorn; Kluytmans, Jan; Gits, Etty; van Duyn, Inge; Heck, Max; van der Zwaluw, Kim; Wannet, Wim; Noordhoek, Gerda T.; Mulder, Sije; Renders, Nicole; Boers, Miranda; Zaat, Sebastiaan; van der Riet, Daniëlle; Kooistra, Mirjam; Talens, Adriaan; Dijkshoorn, Lenie; van der Reyden, Tanny; Veenendaal, Dick; Bakker, Nancy; Cookson, Barry; Lynch, Alisson; Witte, Wolfgang; Cuny, Christa; Blanc, Dominique; Vernez, Isabelle; Hryniewicz, Waleria; Fiett, Janusz; Struelens, Marc; Deplano, Ariane; Landegent, Jim; Verbrugh, Henri A.; van Belkum, Alex

    2002-01-01

    The reproducibility of the binary typing (BT) protocol developed for epidemiological typing of Staphylococcus aureus was analyzed in a biphasic multicenter study. In a Dutch multicenter pilot study, 10 genetically unique isolates of methicillin-resistant S. aureus (MRSA) were characterized by the BT

  12. Heterogeneity of the humoral immune response following Staphylococcus aureus bacteremia

    NARCIS (Netherlands)

    N.J. Verkaik (Nelianne); H.A.M. Boelens (Hélène); C.P. de Vogel (Corné); M. Tavakol (Mehri); L.G.M. Bode (Lonneke); H.A. Verbrugh (Henri); A.F. van Belkum (Alex); W.J.B. van Wamel (Willem)

    2010-01-01

    textabstractExpanding knowledge on the humoral immune response in Staphylococcus aureus-infected patients is a mandatory step in the development of vaccines and immunotherapies. Here, we present novel insights into the antibody responses following S. aureus bacteremia. Fifteen bacteremic patients

  13. Detection of some virulence factors in Staphylococcus aureus ...

    African Journals Online (AJOL)

    pathogens that can cause mastitis, Staphylococcus aureus is probably the most lethal agent because it causes chronic and deep infection in the mammary glands that is extremely difficult to be cured. The present study was to detect some of the virulence factors in the S. aureus isolated from 360 mastitis milk samples in ...

  14. Staphylococcus aureus from the German general population is highly diverse

    NARCIS (Netherlands)

    Becker, Karsten; Schaumburg, Frieder; Fegeler, Christian; Friedrich, Alexander W.; Kock, Robin

    Objectives: This prospective cohort study evaluates colonization dynamics and molecular characteristics of methicillin-susceptible and - resistant Staphylococcus aureus (MSSA/MRSA) in a German general population. Methods: Nasal swabs of 1878 non-hospitalized adults were screened for S. aureus.

  15. Invasive Staphylococcus aureus infection in an African adolescent ...

    African Journals Online (AJOL)

    Staphylococcus aureus remains an important cause of mortality, in the community and health care set-ups. S. aureus strains with genes encoding lethal toxins and culture negative sepsis augment the diagnostic challenge in resource limited settings. With a growing rate of resistance to the causative bacteria and atypical ...

  16. Nasal carriage of multi-drug resistant Staphylococcus aureus in ...

    African Journals Online (AJOL)

    Background: Nasal Staphylococcus aureus is a major source of community and hospital associated staphylococcal infections. This study determined the prevalence of nasal S. aureus isolates and investigated their antimicrobial resistance profile in healthy volunteers. Methods: Nasal specimens of healthy volunteers in ...

  17. Detection and identification of Staphylococcus aureus in raw milk by ...

    African Journals Online (AJOL)

    Staphylococcus aureus causes foodborne diseases if consumed in contaminated milk products. Rapid detection and characterization of foodborne pathogen S. aureus is crucial for epidemiological investigations and food safety surveillance. It is still a challenge to detect and identify bacterial pathogens quickly and ...

  18. Toxins and adhesion factors associated with Staphylococcus aureus ...

    African Journals Online (AJOL)

    Staphylococcus aureus is a causative agent of acute and infectious diarrhoea. In Africa, there is no sufficient information on the virulence and the degree of factors produced by its diarrhoea-isolated strains. Clinical features and virulence factors produced by S. aureus isolated from diarrhoeal-patients admitted at the ...

  19. Staphylococcus aureus ST398 from slaughter pigs in northeast China

    NARCIS (Netherlands)

    Yan, Xiaomei; Yu, Xiaojie; Tao, Xiaoxia; Zhang, Jianfeng; Zhang, Binghua; Dong, Rui; Xue, Chengyu; Grundmann, Hajo; Zhang, Jianzhong

    To describe the prevalence and population structure of Staphylococcus aureus bacteria that colonize pigs at slaughterhouses in northeastern China, nose swabs were collected from pigs in two slaughterhouses in Harbin, Heilongjiang Province, China in 2009.S. aureus isolates were characterized by

  20. Pneumonia and new methicillin-resistant Staphylococcus aureus clone.

    NARCIS (Netherlands)

    Garnier, Fabien; Tristan, Anne; François, Bruno; Etienne, Jerome; Delage-Corre, Manuella; Martin, Christian; Liassine, Nadia; Wannet, Wim; Denis, François; Ploy, Marie-Cécile

    2006-01-01

    Necrotizing pneumonia caused by Staphylococcus aureus strains carrying the Panton-Valentin leukocidin gene is a newly described disease entity. We report a new fatal case of necrotizing pneumonia. An S. aureus strain with an agr1 allele and of a new sequence type 377 was recovered, representing a

  1. Nasal carriage of methicilli-resistant staphylococcus aureus with ...

    African Journals Online (AJOL)

    Staphylococcus aureus isolates were collected from anterior nares of fifty healthy adults in Zaria and their antibiotic susceptibility patterns determined. Seventy-two percent (72%) of the isolates were methicillin-resistant S. aureus, while 20% were methicillin-susceptible. The isolates were generally resistant to multiple ...

  2. Prevalence of Methicillin–Resistant Staphylococcus aureus (MRSA ...

    African Journals Online (AJOL)

    Staphylococcus aureus is a major bacterial pathogen that causes different community and hospital-acquired infections. Over time, strains of S. aureus have become resistant to different antibiotics including penicillinase-resistant penicillins. Having data on the local antimicrobial susceptibility pattern of this pathogen is ...

  3. Detection of some virulence factors in Staphylococcus aureus ...

    African Journals Online (AJOL)

    USER

    2010-06-21

    Jun 21, 2010 ... present study was to detect some of the virulence factors in the S. aureus isolated from 360 mastitis milk samples in ... Key words: Bovine mastitis, Staphylococcus aureus, virulence factors, polymerase chain reaction (PCR), Iran. INTRODUCTION ..... staphylococcal hemolysins. Zentralbl Bakteriol Orig A.

  4. Virulence potential of Staphylococcus aureus isolates from Buruli ulcer patients

    NARCIS (Netherlands)

    Amissah, Nana Ama; Chlebowicz, Monika A.; Ablordey, Anthony; Tetteh, Caitlin S.; Prah, Isaac; van der Werf, Tjip S.; Friedrich, Alex W.; van Dijl, Jan Maarten; Stienstra, Ymkje; Rossen, John W.

    Buruli ulcer (BU) is a necrotizing infection of the skin and subcutaneous tissue caused by Mycobacterium ulcerans. BU wounds may also be colonized with other microorganisms including Staphylococcus aureus. This study aimed to characterize the virulence factors of S. aureus isolated from BU patients.

  5. Staphylococcus aureus in mastitic crossbreed cows and its ...

    African Journals Online (AJOL)

    and its associated risk factors in Addis Ababa City,. Ethiopia ... and wide spread livestock diseases (Mohammed Ahmed et al., 2004). Mastitis .... Legesse Garedew et al.,. Table 2: Risk factors associated with the occurrence of Staphylococcus aureus in mastitic cows. Risk factor. Total animals S. aureus positives. X2 p-value.

  6. Carriage of Staphylococcus aureus on armpits of secondary school ...

    African Journals Online (AJOL)

    A study of carriage of Staphylococcus aureus on armpits and factors affecting it was carried out on 50 students from Community Secondary School, Oroworokwu, Port Harcourt and 50 University of Port Harcourt students. Samples were inoculated onto mannitol salt agar plates and coagulate positive S. aureus isolates were ...

  7. Typing of Staphylococcus aureus strains isolated from milk cows ...

    African Journals Online (AJOL)

    Surveys conducted in Senegal have shown a strong association of staphylococci with subclinical mastitis in dairy cows. This study aimed to characterise Staphylococcus aureus strains identified in the dairy farms in Dakar. Of a total of 244 Staphylococcus spp isolates col ected from 135 lactating cows with subclinical ...

  8. Citral, a monoterpenoid aldehyde interacts synergistically with norfloxacin against methicillin resistant Staphylococcus aureus.

    Science.gov (United States)

    Gupta, Priyanka; Patel, Dinesh Kumar; Gupta, Vivek Kumar; Pal, Anirban; Tandon, Sudeep; Darokar, M P

    2017-10-15

    Staphylococcus aureus (SA), is a major human pathogen causing wide range of clinical infections, which has been further complicated by drug resistance like methicillin resistant S. aureus (MRSA), vancomycin intermediate S. aureus (VISA)/vancomycin resistant S. aureus (VRSA), etc. The present study was aimed at determining anti-staphylococcal potential of citral against drug resistant clinical isolates alone and in combination with antibiotics. To assess the potential of citral in combination with norfloxacin in treating drug resistant infections of SA. In the present study, synergistic interaction of citral and norfloxacin against drug resistant SA strains was evaluated. Further the efficacy and possible mechanism of action of the combination was also evaluated using in vitro and in vivo assays. The anti-staphylococcal activity of each of the monoterpene and the antibiotic was determined in terms of MIC and the effective concentration of both compounds in combination was obtained by checkerboard assay. In vivo efficacy and oral acute toxicity was evaluated in Swiss albino mice model. To understand the mechanism of action, time-kill curve, bacteriolysis, leakage, membrane depolarization, salt tolerance and ethidium bromide efflux assays were performed. Citral was found effective against clinical isolates of SA with MIC values ranging from 75 to 150 µg ml-1 exhibiting bacteriostatic activity. Citral interacted synergistically, reducing MIC of norfloxacin up to 32-folds with FICI ≤ 0.50. Citral did not affect cell wall, but could damage cell membrane, inhibit efflux pump and affect the membrane potential. Citral could reduce the staphylococcal load of spleen and liver tissues in a dose-dependent manner which was further reduced when used in combination with norfloxacin. Citral did not exhibit any mortality or morbidity up to 500 mg kg-1 body weight and found to prolong the post-antibiotic effect of norfloxacin. Based on these observations, citral could be a

  9. Staphylococcus aureus nasal carriage in hemodialysis centers of Fez, Morocco

    OpenAIRE

    Idrissa Diawara; Khadija Bekhti; Driss Elhabchi; Rachid Saile; Naima Elmdaghri; Mohammed Timinouni; Mohamed Elazhari

    2014-01-01

    Background and objectives Staphylococcus aureus (S. aureus) nasal carriage may be responsible for some serious infections in hemodialyzed patients. The main target of this study was to estimate the prevalence of S. aureus nasal carriage in hemodialysis outpatients and medical staff in hemodialysis centers specifically in Fez region. The second target is to identify the risks of colonization, resistance pattern of isolates and their virulence toxin genes. Patients and Methods Nasal swab specim...

  10. Predictors of Mortality in Staphylococcus aureus Bacteremia

    Science.gov (United States)

    Jensen, Slade O.; Vaska, Vikram L.; Espedido, Björn A.; Paterson, David L.; Gosbell, Iain B.

    2012-01-01

    Summary: Staphylococcus aureus bacteremia (SAB) is an important infection with an incidence rate ranging from 20 to 50 cases/100,000 population per year. Between 10% and 30% of these patients will die from SAB. Comparatively, this accounts for a greater number of deaths than for AIDS, tuberculosis, and viral hepatitis combined. Multiple factors influence outcomes for SAB patients. The most consistent predictor of mortality is age, with older patients being twice as likely to die. Except for the presence of comorbidities, the impacts of other host factors, including gender, ethnicity, socioeconomic status, and immune status, are unclear. Pathogen-host interactions, especially the presence of shock and the source of SAB, are strong predictors of outcomes. Although antibiotic resistance may be associated with increased mortality, questions remain as to whether this reflects pathogen-specific factors or poorer responses to antibiotic therapy, namely, vancomycin. Optimal management relies on starting appropriate antibiotics in a timely fashion, resulting in improved outcomes for certain patient subgroups. The roles of surgery and infectious disease consultations require further study. Although the rate of mortality from SAB is declining, it remains high. Future international collaborative studies are required to tease out the relative contributions of various factors to mortality, which would enable the optimization of SAB management and patient outcomes. PMID:22491776

  11. [Dispersal of Staphylococcus aureus from nasal carriers].

    Science.gov (United States)

    Iskandar, Aline; Nguyen, Ngan; Kolmos, Hans Jørn

    2009-02-02

    Staphylococcus aureus (Sa) is an important cause of hospital-acquired infections, and nasal carriage of Sa is common among health care workers. This study was designed to measure the airborne dispersal of Sa and other bacteria from such carriers and to investigate whether the use of cap, gown, gloves, and mask could reduce this dispersal. A total of 13 nasal Sa carriers were identified among 63 persons screened for Sa nasal carriage. The volunteers were studied for airborne dispersal of Sa in four different situations: quiet breathing, movements of the arms, whispering and loud talking. These activities were performed with and without gown, gloves, mask and cap upon street clothes. The study showed that the highest number of Sa and bacteria in total was dispersed into the air when the volunteers were moving and wearing only their street clothes. The dispersal of Sa into the air was reduced into a minimum by wearing cap, gown and gloves, and no further significant decrease was achieved by wearing a mask. This applied for all volunteers except for one, who had to wear a mask in order to reduce his dispersal of Sa to a minimum. The total dispersal of bacteria was significantly reduced by wearing cap, gown and gloves; however, to reduce this dispersal to a minimum, volunteers also had to wear a mask. Our study supports the rational basis that gown, cap, gloves and mask should be used not only in the operating theatre, but also while e.g. inserting central venous catheters.

  12. Nasal Staphylococcus aureus and methicillin-resistant Staphylococcus aureus carriage among college student athletes in northern Taiwan

    Directory of Open Access Journals (Sweden)

    Hong-Kai Wang

    2017-08-01

    Full Text Available Of 259 college students in northern Taiwan surveyed, nasal carriage rate of Staphylococcus aureus and methicillin-resistant S. aureus (MRSA was 22.4% and 1.54%, respectively and no significant difference was found between athlete students and non-athlete students. Three of four MRSA isolates belonged to sequence type 59, the endemic community clone.

  13. Selective biosensing of Staphylococcus aureus using chitosan quantum dots

    Science.gov (United States)

    Abdelhamid, Hani Nasser; Wu, Hui-Fen

    2018-01-01

    Selective biosensing of Staphylococcus aureus (S. aureus) using chitosan modified quantum dots (CTS@CdS QDs) in the presence of hydrogen peroxide is reported. The method is based on the intrinsic positive catalase activity of S. aureus. CTS@CdS quantum dots provide high dispersion in aqueous media with high fluorescence emission. Staphylococcus aureus causes a selective quenching of the fluorescence emission of CTS@CdS QDs in the presence of H2O2 compared to other pathogens such as Escherichia coli and Pseudomonas aeruginosa. The intrinsic enzymatic character of S. aureus (catalase positive) offers selective and fast biosensing. The present method is highly selective for positive catalase species and requires no expensive reagents such as antibodies, aptamers or microbeads. It could be extended for other species that are positive catalase.

  14. Characterization of methicillin-resistant Staphylococcus aureus Sequence Type 398

    DEFF Research Database (Denmark)

    Christiansen, Mette Theilgaard

    . aureus and methicillin-resistant Staphylococcus aureus (MRSA) have been associated with hospitals, but during the past decades MRSA has emerged in the community and now a new branch of MRSA has been found in association with livestock (LA-MRSA). A specific lineage (multilocus sequence type 398 (ST398......Staphylococcus aureus is an opportunistic pathogen that colonizes the nares and skin surfaces of several animal species, including man. S. aureus can cause a wide variety of infections ranging from superficial soft tissue and skin infections to severe and deadly systemic infections. Traditionally S...... for LA-MRSA ST398 survival on porcine skin and nasal epithelium ex vivo were identified. These genes could represent targets for de-colonization, which could help prevent further spread and adaption of LA-MRSA ST398. Manuscript III describes the construction of the S. aureus VirulenceFinder database...

  15. Genotypic and phenotypic characteristics of Methicillin-resistant Staphylococcus aureus (MRSA) strains, isolated on three different geography locations.

    Science.gov (United States)

    Ostojić, Maja; Hukić, Mirsada

    2015-08-04

    Staphylococcus aureus is a major cause of hospital-acquired infections worldwide. Increased frequency of methicillin-resistant Staphylococcus aureus (MRSA) in hospitalized patients and possibility of vancomycin resistance requires rapid and reliable characterization of isolates and control of MRSA spread in hospitals. Typing of isolates helps to understand the route of a hospital pathogen spread. The aim of this study was to investigate and compare genotypic and phenotypic characteristics of MRSA samples on three different geography locations. In addition, our aim was to evaluate three different methods of MRSA typing: spa-typing, agr-typing and GenoType MRSA.  We included 104 samples of MRSA, isolated in 3 different geographical locations in clinical hospitals in Zagreb, Mostar, and Heidelberg, during the period of six months. Genotyping and phenotyping were done by spa-typing, agr-typing and dipstick assay GenoType MRSA. We failed to type all our samples by spa-typing.  The most common spa-type in clinical hospital Zagreb was t041, in Mostar t001, and in Heidelberg t003.We analyzed 102/104 of our samples by agr-typing method. We did not find any agr-type IV in our locations. We analyzed all our samples by the dipstick assay GenoType MRSA. All isolates in our study were MRSA strains. In Zagreb there were no positive strains to PVL gene. In Mostar we have found 5/25 positive strains to PVL gene, in Heidelberg there was 1/49. PVL positive isolates were associated with spa-type t008 and agr-type I, thus, genetically, they were community-associated MRSA (CA-MRSA). Dipstick assay GenoType MRSA has demonstrated sufficient specificity, sensibility, simple performance and low cost, so we could introduce it to work in smaller laboratories. Using this method may expedite MRSA screening, thus preventing its spread in hospitals.

  16. Radioimmunoassays for protein A of Staphylococcus aureus

    Energy Technology Data Exchange (ETDEWEB)

    Langone, J.J.; Das, C.; Bennett, D.; Terman, D.S. (Baylor Univ., Houston, TX (USA). Coll. of Medicine)

    1983-10-14

    Radioimmunoassays have been developed that can detect nanogram amounts of protein A (SpA), a product generated by Staphylococcus aureus that binds selectively to the Fc region of IgG from most mammalian species. Competition assays for fluid phase SpA utilize antibodies produced in chickens, /sup 125/I-labeled SpA as the tracer molecule, and either F(ab')/sub 2/ fragments of rabbit IgG anti-chicken IgG or 40% ammonium sulfate as the precipitating agent to separate antigen-antibody complexes from free antigen. The double antibody assay could be carried out in serum from species that form only soluble complexes with SpA (e.g., rabbit), that react poorly with SpA (e.g., rat) or under appropriate conditions in serum from species (e.g., dog) that show high reactivity with SpA and form precipitating complexes. Chicken antibodies prepared by affinity chromatography on SpA-Sepharose and labeled with /sup 125/I were used in a direct binding assay for SpA present either on the cell wall of Cowan strain I or Wood 46 bacteria, in insoluble complexes prepared from SpA and whole serum or purified IgG, or in C1q binding complexes that were formed by passage of serum from normal or tumor bearing humans or dogs over SpA-collodion charcoal. Since both types of assays could detect SpA even in the presence of serum or IgG, they offer advantages over other techniques in which the SpA-Fc interaction may interfere.

  17. Comparative genomic analysis of the genus Staphylococcus including Staphylococcus aureus and its newly described sister species Staphylococcus simiae

    Science.gov (United States)

    2012-01-01

    Background Staphylococcus belongs to the Gram-positive low G + C content group of the Firmicutes division of bacteria. Staphylococcus aureus is an important human and veterinary pathogen that causes a broad spectrum of diseases, and has developed important multidrug resistant forms such as methicillin-resistant S. aureus (MRSA). Staphylococcus simiae was isolated from South American squirrel monkeys in 2000, and is a coagulase-negative bacterium, closely related, and possibly the sister group, to S. aureus. Comparative genomic analyses of closely related bacteria with different phenotypes can provide information relevant to understanding adaptation to host environment and mechanisms of pathogenicity. Results We determined a Roche/454 draft genome sequence for S. simiae and included it in comparative genomic analyses with 11 other Staphylococcus species including S. aureus. A genome based phylogeny of the genus confirms that S. simiae is the sister group to S. aureus and indicates that the most basal Staphylococcus lineage is Staphylococcus pseudintermedius, followed by Staphylococcus carnosus. Given the primary niche of these two latter taxa, compared to the other species in the genus, this phylogeny suggests that human adaptation evolved after the split of S. carnosus. The two coagulase-positive species (S. aureus and S. pseudintermedius) are not phylogenetically closest but share many virulence factors exclusively, suggesting that these genes were acquired by horizontal transfer. Enrichment in genes related to mobile elements such as prophage in S. aureus relative to S. simiae suggests that pathogenesis in the S. aureus group has developed by gene gain through horizontal transfer, after the split of S. aureus and S. simiae from their common ancestor. Conclusions Comparative genomic analyses across 12 Staphylococcus species provide hypotheses about lineages in which human adaptation has taken place and contributions of horizontal transfer in pathogenesis. PMID

  18. Whole Genome Sequencing of Danish Staphylococcus argenteus Reveals a Genetically Diverse Collection with Clear Separation from Staphylococcus aureus

    OpenAIRE

    Hansen, Thomas A.; Bartels, Mette D.; Hogh, Silje V.; Dons, Lone E.; Pedersen, Michael; Jensen, Thoger G.; Kemp, Michael; Skov, Marianne N.; Gumpert, Heidi; Worning, Peder; Westh, Henrik

    2017-01-01

    Staphylococcus argenteus (S. argenteus) is a newly identified Staphylococcus species that has been misidentified as Staphylococcus aureus (S. aureus) and is clinically relevant. We identified 25 S. argenteus genomes in our collection of whole genome sequenced S. aureus. These genomes were compared to publicly available genomes and a phylogeny revealed seven clusters corresponding to seven clonal complexes. The genome of S. argenteus was found to be different from the genome of S. aureus and a...

  19. [Vancomycin-resistant Enterococcus spp. strains].

    Science.gov (United States)

    Kozuszko, Sylwia; Bogiel, Tomasz; Gospodarek, Eugenia

    2009-01-01

    The aim of our study was to evaluate a frequency of isolation and susceptibility to antibiotics of vancomycin-resistant enterococci isolated between 2005 and the first half of the 2009 from patients of University Hospital of Dr. A. Jurasz Collegium Medicum of L. Rydygier in Bydgoszcz Nicolaus Copernicus University in Toruli. Study shows increasing frequency of VRE isolation from two in 2005, 8 in 2006, 30 in 2007 to 79 in 2008 and 40 in the first half of 2009 year. Among all isolated VRE strains E. faecium definitely predominated (75.0-90.0% in 2006-2009). The majority of strains were obtained from patients of the Pediatrics, Hematology and Oncology Clinic (43,4%) and Pediatric Surgery Clinic (41.5%). VRE strains were mainly isolated from digestive tract (79,9%). The isolates demonstrated frequently resistance to penicillin, ampicillin, ciprofloxacin, rifampicin and chloramphenicol. Percentage of VRE strain resistant to aminoglycosides decreased during the last four years of study. Over 56% of VRE isolates showed resistance to teicoplanin. Linezolid and quinupristin-dalfopristin were the only drugs presenting activity against isolated VRE strains.

  20. Antimicrobial resistance of Staphylococcus aureus isolates from dairy cows and genetic diversity of resistant isolates

    Science.gov (United States)

    Staphylococcus aureus is a frequent and major contagious mastitis bacterial pathogen. The antibiotic treatment cure rates vary considerably from 4% to 92%. Staphylococcus aureus readily becomes resistant to antibiotics, resulting in persistent noncurable intramammary infection that usually results i...

  1. Molecular and mathematical epidemiology of Staphylococcus aureus and Streptococcus uberis mastitis in dairy herds

    NARCIS (Netherlands)

    Zadoks, Ruth Nicolet

    2002-01-01

    Mastitis is the most common and costly production disease affecting dairy cows. Staphylococcus aureus and Streptococcus uberis are two major mastitis-causing pathogens. Staphylococcus aureus is traditionally classified as contagious pathogen, while Streptococcus uberis is classified as environmental

  2. High-level oxacillin and gentamycin resistance with reduced susceptibility to vancomycin in Staphylococcus aureus-carrying mecA and femA gene complex.

    Science.gov (United States)

    Raju, S; Kelmani Chandrakanth, R; Patil, S A

    2007-06-01

    Staphylococcus aureus oxiva 10 and oxiva 14 strains clinically isolated from diabetic patients were resistant to gentamycin and oxacillin The minimal inhibitory concentrations (MICs) of oxacillin and gentamycin were 720 and >2048 microg/mL, respectively, for oxiva 10 and 680 and 400 microg/mL. respectively, for oxiva 14; both strains carry mecA and femA genetic determinants in their genomes. In addition, both are vancomycin-intermediate Staphylococcus aureus (VISA) isolates. The addition of vancomycin led to significant decreases in oxacillin resistance of both oxiva 10 and oxiva 14 strains, whereas the addition of vancomycin to gentamycin plates showed a decrease in gentamycin resistance of non-high-level gentamycin-resistant (non-HLGR) oxiva 14 and indifference in gentamycin resistance in HLGR oxiva 10. Transmission electron microscopy of representative strains unveils a remarkable increase in the thickness of the cell wall, indicating that thickening of the cell wall is a common phenotype associated with vancomycin resistance in VISA isolates. The present study reports that the rate of synergism and synergistic effect in the combination vancomycin-gentamycin vary according to the MICs of gentamycin.

  3. Magnetic nanoparticle targeted hyperthermia of cutaneous Staphylococcus aureus infection

    Science.gov (United States)

    Kim, Min-Ho; Yamayoshi, Itsukyo; Mathew, Steven; Liln, Hubert; Nayfach, Joseph; Simon, Scott I.

    2013-01-01

    The incidence of wound infections that do not adequately respond to standard-of-care antimicrobial treatment has been increasing. To address this challenge, a novel antimicrobial magnetic thermotherapy platform has been developed in which a high-amplitude, high-frequency, alternating magnetic field (AMF) is used to rapidly heat magnetic nanoparticles that are bound to Staphylococcus aureus (S. aureus). The antimicrobial efficacy of this platform was evaluated in the treatment of both an in vitro culture model of S. aureus biofilm and a mouse model of cutaneous S. aureus infection. We demonstrated that an antibody-targeted magnetic nanoparticle bound to S. aureus was effective at thermally inactivating S. aureus and achieving accelerated wound healing without causing tissue injury. PMID:23149904

  4. Staphylococcus aureus sternal osteomyelitis: a rare cause of chest pain

    Directory of Open Access Journals (Sweden)

    Kaur M

    2015-10-01

    Full Text Available Chest pain is a common presenting symptom with a broad differential. Life-threatening cardiac and pulmonary etiologies of chest pain should be evaluated first. However, it is critical to perform a thorough assessment for other sources of chest pain in order to limit morbidity and mortality from less common causes. We present a rare case of a previously healthy 45 year old man who presented with focal, substernal, reproducible chest pain and Staphylococcus aureus bacteremia who was later found to have primary Staphylococcus aureus sternal osteomyelitis.

  5. Methicillin-resistant Staphylococcus aureus in a neonatal alpaca

    OpenAIRE

    Stull, Jason W.; Kenney, Daniel G.; Slavić, Durda; Weese, J Scott

    2012-01-01

    A 6-hour-old alpaca was presented for evaluation of respiratory difficulty. As part of routine surveillance, methicillin-resistant Staphylococcus aureus (MRSA) was identified from a nasal swab taken upon admission to the hospital. No signs of MRSA infection were noted. The MRSA strain recovered was a human epidemic clone that has been associated with horses. Methicillin-resistant S. aureus colonization can occur in camelids, and the potential animal and public health risks require consideration.

  6. Piperine, a Phytochemical Potentiator of Ciprofloxacin against Staphylococcus aureus

    Science.gov (United States)

    Khan, Inshad Ali; Mirza, Zahid Mehmood; Kumar, Ashwani; Verma, Vijeshwar; Qazi, Ghulam Nabi

    2006-01-01

    Piperine, a trans-trans isomer of 1-piperoyl-piperidine, in combination with ciprofloxacin markedly reduced the MICs and mutation prevention concentration of ciprofloxacin for Staphylococcus aureus, including methicillin-resistant S. aureus. The enhanced accumulation and decreased efflux of ethidium bromide in the wild-type and mutant (CIPr-1) strains in the presence of piperine suggest its involvement in the inhibition of bacterial efflux pumps. PMID:16436753

  7. Biochemical characters and antibiotic susceptibility of Staphylococcus aureus isolates

    OpenAIRE

    Subhankari Prasad Chakraborty; Santanu Kar Mahapatra; Somenath Roy

    2011-01-01

    Objective: To observe the biochemical characters and antibiotic susceptibility of isolated Staphylococcus aureus (S. auerus) strains against some conventional and traditional antibiotics. Methods: Thirty post operative pathogenic isolated S. aureus strains were used in this study. Bacterial culture was done in Mueller-Hinton broth at 37 °C. Characters of these strains were determined by traditional biochemical tests such as hydrolysis test of gelatin, urea, galactose, starch and protein, a...

  8. Glucose Augments Killing Efficiency of Daptomycin Challenged Staphylococcus aureus Persisters

    OpenAIRE

    Prax, Marcel; Mechler, Lukas; Weidenmaier, Christopher; Bertram, Ralph

    2016-01-01

    Treatment of Staphylococcus aureus in stationary growth phase with high doses of the antibiotic daptomycin (DAP) eradicates the vast majority of the culture and leaves persister cells behind. Despite resting in a drug-tolerant and dormant state, persister cells exhibit metabolic activity which might be exploited for their elimination. We here report that the addition of glucose to S. aureus persisters treated with DAP increased killing by up to five-fold within one hour. This glucose-DAP effe...

  9. Staphylococcus aureus Redirects Central Metabolism to Increase Iron Availability

    OpenAIRE

    Stauff, Devin L; Pishchany, Gleb; Whitwell, Corbin W; Torres, Victor J; Skaar, Eric P; Friedman, David J.

    2006-01-01

    Staphylococcus aureus pathogenesis is significantly influenced by the iron status of the host. However, the regulatory impact of host iron sources on S. aureus gene expression remains unknown. In this study, we combine multivariable difference gel electrophoresis and mass spectrometry with multivariate statistical analyses to systematically cluster cellular protein response across distinct iron-exposure conditions. Quadruplicate samples were simultaneously analyzed for alterations in protein ...

  10. Molecular dynamics of Staphylococcus aureus nasal carriage in Hajj pilgrims.

    Science.gov (United States)

    Verhoeven, P O; Gautret, P; Haddar, C H; Benkouiten, S; Gagnaire, J; Belhouchat, K; Grattard, F; Charrel, R; Pozzetto, B; Drali, T; Lucht, F; Brouqui, P; Memish, Z A; Berthelot, P; Botelho-Nevers, E

    2015-07-01

    During the 2012 Hajj season, the risk of acquisition of Staphylococcus aureus nasal carriage in a cohort of French pilgrims was 22.8%, and was statistically associated with the acquisition of viral respiratory pathogens (p 0.03). The carriage of S. aureus belonging to the emerging clonal complex 398 significantly increased following the pilgrimage (p < 0.05). Copyright © 2015 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  11. Minimum inhibitory concentration of vancomycin to methicillin resistant Staphylococcus aureus isolated from different clinical samples at a tertiary care hospital in Nepal.

    Science.gov (United States)

    Kshetry, Arjun Ojha; Pant, Narayan Dutt; Bhandari, Raju; Khatri, Sabita; Shrestha, Krishma Laxmi; Upadhaya, Shambhu Kumar; Poudel, Asia; Lekhak, Binod; Raghubanshi, Bijendra R

    2016-01-01

    Methicillin resistant Staphylococcus aureus (MRSA) has evolved as a serious threat to public health. It has capability to cause infections not only in health care settings but also in community. Due to the multidrug resistance shown by MRSA, there are limited treatment options for the infections caused by this superbug. Vancomycin is used as the drug of choice for the treatment of infections caused by MRSA. Different studies from all around the world have documented the emergence of strains of S. aureus those are intermediate sensitive or resistant to vancomycin. And recently, there have been reports of reduced susceptibility of MRSA to vancomycin, from Nepal also. So the main purpose of this study was to determine the minimum inhibitory concentration (MIC) of vancomycin to methicillin resistant S. aureus isolated from different clinical specimens. Total 125 strains of S. aureus isolated from different clinical samples at KIST Medical College and Teaching Hospital, Lalitpur, Nepal from Nov 2012 to June 2013, were subjected to MRSA detection by cefoxitin disc diffusion method. The minimum inhibitory concentrations of vancomycin to confirmed MRSA strains were determined by agar dilution method. Yellow colored colonies in mannitol salt agar, which were gram positive cocci, catalase positive and coagulase positive were confirmed to be S. aureus. Among, total 125 S. aureus strains isolated; 47(37.6%) were MRSA. Minimum inhibitory concentrations of vancomycin to the strains of MRSA ranged from 0.125 μg/ml to 1 μg/ml. From our findings we concluded that the rate of isolation of MRSA among all the strains of S. aureus isolated from clinical samples was very high. However, none of the MRSA strains were found to be vancomycin intermediate-sensitive or vancomycin-resistant.

  12. Minimum inhibitory concentration of vancomycin to methicillin resistant Staphylococcus aureus isolated from different clinical samples at a tertiary care hospital in Nepal

    Directory of Open Access Journals (Sweden)

    Arjun Ojha Kshetry

    2016-07-01

    Full Text Available Abstract Background Methicillin resistant Staphylococcus aureus (MRSA has evolved as a serious threat to public health. It has capability to cause infections not only in health care settings but also in community. Due to the multidrug resistance shown by MRSA, there are limited treatment options for the infections caused by this superbug. Vancomycin is used as the drug of choice for the treatment of infections caused by MRSA. Different studies from all around the world have documented the emergence of strains of S. aureus those are intermediate sensitive or resistant to vancomycin. And recently, there have been reports of reduced susceptibility of MRSA to vancomycin, from Nepal also. So the main purpose of this study was to determine the minimum inhibitory concentration (MIC of vancomycin to methicillin resistant S. aureus isolated from different clinical specimens. Methods Total 125 strains of S. aureus isolated from different clinical samples at KIST Medical College and Teaching Hospital, Lalitpur, Nepal from Nov 2012 to June 2013, were subjected to MRSA detection by cefoxitin disc diffusion method. The minimum inhibitory concentrations of vancomycin to confirmed MRSA strains were determined by agar dilution method. Yellow colored colonies in mannitol salt agar, which were gram positive cocci, catalase positive and coagulase positive were confirmed to be S. aureus. Results Among, total 125 S. aureus strains isolated; 47(37.6% were MRSA. Minimum inhibitory concentrations of vancomycin to the strains of MRSA ranged from 0.125 μg/ml to 1 μg/ml. Conclusion From our findings we concluded that the rate of isolation of MRSA among all the strains of S. aureus isolated from clinical samples was very high. However, none of the MRSA strains were found to be vancomycin intermediate-sensitive or vancomycin-resistant.

  13. Staphylococcus aureus effect of different factors on mammary gland infection with staphylococcus aureus bacteria

    Directory of Open Access Journals (Sweden)

    Jurčevič Alen

    2004-01-01

    Full Text Available The objective of our investigation was to determine how certain factors (the environment, treatment, prevention, animal affect udder infection with Staphylococcus aureurs (S. aureus bacteria. A questionnaire investigated the effect of different factors on the frequency of infection with S. aureus bacteria. We established that prevention, treatment on the basis of results of bacteriological examinations and antibiograms, and the elimination of the negative influence of the environment, form a basis for reducing the frequency of udder infections. We verified the questionannire results with the variant analysis method and established that the effect of the environment significantly digresses from the other factors (prevention treatment and diagnosis, animal. Our results show that the breeder, with good prevention and good treatment of mastitis, often disregards the effects of the barn and the environment in which the cows are maintained. Poor barn conditions have a negative effect on cow resistance and at the same time enable the existence and multiplication of pathogenic species of bacteria. In addition to the maintenance conditions, one must not forget prevention and therapy of mammary gland inflammation, either. On the grounds of our previous investigations (Pengov et al., 2000, we recommend for the therapy of mammary gland inflammation the use of a combination of amoxicillin and clavulonic acid, and as prevention of mammary gland inflammation the use of an udder ointment.

  14. Stilbenes reduce Staphylococcus aureus hemolysis, biofilm formation, and virulence.

    Science.gov (United States)

    Lee, Kayeon; Lee, Jin-Hyung; Ryu, Shi Yong; Cho, Moo Hwan; Lee, Jintae

    2014-09-01

    Stilbenoids have a broad range of beneficial health effects. On the other hand, the emergence of antibiotic-resistant Staphylococcus aureus presents a worldwide problem that requires new antibiotics or nonantibiotic strategies. S. aureus produces α-hemolysin (a pore-forming cytotoxin) that has been implicated in the pathogenesis of sepsis and pneumonia. Furthermore, the biofilms formed by S. aureus constitute a mechanism of antimicrobial resistance. In this study, we investigated the hemolytic and antibiofilm activities of 10 stilbene-related compounds against S. aureus. trans-Stilbene and resveratrol at 10 μg/mL were found to markedly inhibit human blood hemolysis by S. aureus, and trans-stilbene also inhibited S. aureus biofilm formation without affecting its bacterial growth. Furthermore, trans-stilbene and resveratrol attenuated S. aureus virulence in vivo in the nematode Caenorhabditis elegans, which is normally killed by S. aureus. Transcriptional analysis showed that trans-stilbene repressed the α-hemolysin hla gene and the intercellular adhesion locus (icaA and icaD) in S. aureus, and this finding was in line with observed reductions in virulence and biofilm formation. In addition, vitisin B, a stilbenoid tetramer, at 1 μg/mL was observed to significantly inhibit human blood hemolysis by S. aureus.

  15. Comparison of five tests for identification of Staphylococcus aureus from clinical samples

    NARCIS (Netherlands)

    A. Luijendijk (Ad); A.F. van Belkum (Alex); J.A.J.W. Kluytmans (Jan); H.A. Verbrugh (Henri)

    1996-01-01

    textabstractFive different laboratory tests for the identification of Staphylococcus aureus were compared. Analyses of 271 presumptive S. aureus strains, supplemented with 59 well-defined methicillin-resistant S. aureus (MRSA) isolates, were performed. Only the

  16. Relative prevalence of methicilline resistant Staphylococcus aureus ...

    African Journals Online (AJOL)

    In our region, although methicillin resistance increased in S. aureus strains, because of the unavailability and the high cost of alternative antibiotics, gentamycin is still suggested as an alternative for treatment of S. aureus infections. These results however indicate that vancomycin seemed to be the only antimicrobial agent ...

  17. Prevalence of methicillin resistant Staphylococcus aureus and ...

    African Journals Online (AJOL)

    ... Methicillin Resistant S. aureus (MRSA) in the studied population. Clinical isolates of S. aureus strains were collected from Medical Microbiology Unit of University College Hospital, Ibadan between May and October, 2012. The isolates were confirmed through growth on Mannitol Salt Agar (MSA) and tube coagulase test.

  18. Methicillin-resistant Staphylococcus aureus in a finger felon.

    Science.gov (United States)

    Connolly, B; Johnstone, F; Gerlinger, T; Puttler, E

    2000-01-01

    Methicillin-resistant Staphylococcus aureus is an increasingly prevalent nosocomial pathogen that presents therapeutic challenges. We report an incidence of methicillin-resistant S aureus in a felon. The biochemical and clinical characteristics of methicillin-resistant S aureus are reviewed. The alarming increase of this organism in various types of infections demands the attention of all surgeons and emphasizes the importance of early surgical drainage and culture of pus in all cases of infection. (J Hand Surg 2000; 25A:173-175. Copyright 2000 by the American Society for Surgery of the Hand.).

  19. Staphylococcus aureus and the ecology of the nasal microbiome

    DEFF Research Database (Denmark)

    Liu, Cindy M; Price, Lance B; Hungate, Bruce A

    2015-01-01

    The human microbiome can play a key role in host susceptibility to pathogens, including in the nasal cavity, a site favored by Staphylococcus aureus. However, what determines our resident nasal microbiota-the host or the environment-and can interactions among nasal bacteria determine S. aureus...... colonization? Our study of 46 monozygotic and 43 dizygotic twin pairs revealed that nasal microbiota is an environmentally derived trait, but the host's sex and genetics significantly influence nasal bacterial density. Although specific taxa, including lactic acid bacteria, can determine S. aureus colonization...

  20. The Effect of Essential Oils on Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Seda Ozdikmenli

    2014-05-01

    Full Text Available Diseases caused by Staphylococcus aureus are widespread through the world in spite of developing technology. S. aureus is an important pathogen causing food intoxications besides hospital infections by its antibiotic resistant strains. Nowadays, there has been worldwide increasing concern on usage of natural products to control microorganisms. One of these natural products is essential oils. They are produced from plants especially from spices and composed of many components and volatiles. This review summarizes informative literature on essential oils and their mode of antimicrobial action. In addition, current knowledge on in vitro researches on antibacterial activity of essential oils and food applications to control S. aureus has been discussed.

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

    Science.gov (United States)

    Dilnessa, Tebelay; Bitew, Adane

    2016-08-09

    (10, 5.1 %). MRSA strains were 100 % resistant to penicillin G, erythromycin, trimethoprim-sulfamethoxazole and least resistant to vancomycin (10, 29.4 %). Out of 194 S. aureus isolates (153, 79.0 %) were beta-lactamase producers. In this study S. aureus isolates exhibited very high degree of resistance to different antibiotics. The isolates were also multidrug resistant to several combinations of the tested antibiotics. The emergence of vancomycin resistant S. aureus highlights the value of prudent prescribing of antibiotics and avoiding their irrational use.

  2. Protease production by Staphylococcus epidermidis and its effect on Staphylococcus aureus biofilms.

    Science.gov (United States)

    Vandecandelaere, Ilse; Depuydt, Pieter; Nelis, Hans J; Coenye, Tom

    2014-04-01

    Due to the resistance of Staphylococcus aureus to several antibiotics, treatment of S. aureus infections is often difficult. As an alternative to conventional antibiotics, the field of bacterial interference is investigated. Staphylococcus epidermidis produces a serine protease (Esp) which inhibits S. aureus biofilm formation and which degrades S. aureus biofilms. In this study, we investigated the protease production of 114 S. epidermidis isolates, obtained from biofilms on endotracheal tubes (ET). Most of the S. epidermidis isolates secreted a mixture of serine, cysteine and metalloproteases. We found a link between high protease production by S. epidermidis and the absence of S. aureus in ET biofilms obtained from the same patient. Treating S. aureus biofilms with the supernatant (SN) of the most active protease producing S. epidermidis isolates resulted in a significant biomass decrease compared to untreated controls, while the number of metabolically active cells was not affected. The effect on the biofilm biomass was mainly due to serine proteases. Staphylococcus aureus biofilms treated with the SN of protease producing S. epidermidis were thinner with almost no extracellular matrix. An increased survival of Caenorhabditis elegans, infected with S. aureus Mu50, was observed when the SN of protease positive S. epidermidis was added. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  3. Staphylococcus aureus: nuevos y antiguos antimicrobianos Staphylococcus aureus: new and old antimicrobial agents

    Directory of Open Access Journals (Sweden)

    B. Perazzi

    2010-09-01

    Full Text Available El objetivo del trabajo fue evaluar la sensibilidad a antiguos y nuevos antimicrobianos de aislamientos de Staphylococcus aureus resistentes a la oxacilina, de origen hospitalario (SAOR-H y adquiridos en la comunidad (SAOR-AC, y también en aislamientos sensibles a la oxacilina (SAOS. Se estudió en forma prospectiva la concentración inhibitoria mínima a diversos antimicrobianos en 118 aislamientos consecutivos por dilución seriada en agar según las indicaciones del CLSI. En los aislamientos de SAOR sin resistencia acompañante se determinó la presencia de los genes mec A, leucocidina de Panton Valentine (LPV y γ-hemolisina por PCR, y del cassette SCC mec por PCR múltiple. De los 118 aislamientos estudiados, 44 fueron SAOR-H, 16 SAOR-AC y 58 SAOS. Los aislamientos de SAOR-H presentaron resistencia simultánea a eritromicina, clindamicina, gentamicina, ciprofloxacina, levofloxacina y moxifloxacina, y todos fueron sensibles a tigeciclina (TIG, vancomicina, teicoplanina y linezolid (LZD. Los aislamientos de SAOR-AC fueron resistentes solamente a OXA y sensibles a todos los antimicrobianos ensayados. En todos ellos se detectaron los genes mec A, LPV, γ-hemolisina y el cassette SCC mec IV. En SAOS y en SAOR-AC todos los antimicrobianos no ß-lactámicos ensayados presentaron excelente actividad in vitro, mientras que en SAOR-H sólo los antiguos antimicrobianos como glucopéptidos, doxiciclina, rifampicina y trimetoprima-sulfametoxazol presentaron buena actividad in vitro, al igual que LZD y TIG entre los nuevos antimicrobianos. El fenotipo de SAOR sin resistencia acompañante fue altamente predictivo de SAOR-AC, ya que fue confirmado por presentar el cassette SCC mec IV.The objective of the study was to evaluate the susceptibility to old and new antimicrobial agents against hospital-acquired oxacillin-resistant Staphylococcus aureus (HA-ORSA, community-acquired oxacillin-resistant S. aureus (CA-ORSA, and oxacillin-susceptible S. aureus (OSSA

  4. Staphylococcus aureus vs. Osteoblast: Relationship and Consequences in Osteomyelitis

    Science.gov (United States)

    Josse, Jérôme; Velard, Frédéric; Gangloff, Sophie C.

    2015-01-01

    Bone cells, namely osteoblasts and osteoclasts work in concert and are responsible for bone extracellular matrix formation and resorption. This homeostasis is, in part, altered during infections by Staphylococcus aureus through the induction of various responses from the osteoblasts. This includes the over-production of chemokines, cytokines and growth factors, thus suggesting a role for these cells in both innate and adaptive immunity. S. aureus decreases the activity and viability of osteoblasts, by induction of apoptosis-dependent and independent mechanisms. The tight relationship between osteoclasts and osteoblasts is also modulated by S. aureus infection. The present review provides a survey of the relevant literature discussing the important aspects of S. aureus and osteoblast interaction as well as the ability for antimicrobial peptides to kill intra-osteoblastic S. aureus, hence emphasizing the necessity for new anti-infectious therapeutics. PMID:26636047

  5. Staphylococcus aureus shifts towards commensalism in response to Corynebacterium species

    Directory of Open Access Journals (Sweden)

    Matthew M Ramsey

    2016-08-01

    Full Text Available Staphylococcus aureus–human interactions result in a continuum of outcomes from commensalism to pathogenesis. S. aureus is a clinically important pathogen that asymptomatically colonizes ~25% of humans as a member of the nostril and skin microbiota, where it resides with other bacteria including commensal Corynebacterium species. Commensal Corynebacterium spp. are also positively correlated with S. aureus in chronic polymicrobial diabetic foot infections, distinct from acute monomicrobial S. aureus infections. Recent work by our lab and others indicates that microbe-microbe interactions between S. aureus and human skin/nasal commensals, including Corynebacterium species, affect S. aureus behavior and fitness. Thus, we hypothesized that S. aureus interactions with Corynebacterium spp. diminish S. aureus virulence. We tested this by assaying for changes in S. aureus gene expression during in vitro mono- versus coculture with Corynebacterium striatum, a common skin and nasal commensal. We observed a broad shift in S. aureus gene transcription during in vitro growth with C. striatum, including increased transcription of genes known to exhibit increased expression during human nasal colonization and decreased transcription of virulence genes. S. aureus uses several regulatory pathways to transition between commensal and pathogenic states. One of these, the quorum signal accessory gene regulator (agr system, was strongly inhibited in response to Corynebacterium spp. Phenotypically, S. aureus exposed to C. striatum exhibited increased adhesion to epithelial cells, reflecting a commensal state, and decreased hemolysin activity, reflecting an attenuation of virulence. Consistent with this, S. aureus displayed diminished fitness in experimental in vivo coinfection with C. striatum when compared to monoinfection. These data support a model in which S. aureus shifts from virulence towards a commensal state when exposed to commensal Corynebacterium species.

  6. Staphylococcus aureus Shifts toward Commensalism in Response to Corynebacterium Species

    Science.gov (United States)

    Ramsey, Matthew M.; Freire, Marcelo O.; Gabrilska, Rebecca A.; Rumbaugh, Kendra P.; Lemon, Katherine P.

    2016-01-01

    Staphylococcus aureus–human interactions result in a continuum of outcomes from commensalism to pathogenesis. S. aureus is a clinically important pathogen that asymptomatically colonizes ~25% of humans as a member of the nostril and skin microbiota, where it resides with other bacteria including commensal Corynebacterium species. Commensal Corynebacterium spp. are also positively correlated with S. aureus in chronic polymicrobial diabetic foot infections, distinct from acute monomicrobial S. aureus infections. Recent work by our lab and others indicates that microbe–microbe interactions between S. aureus and human skin/nasal commensals, including Corynebacterium species, affect S. aureus behavior and fitness. Thus, we hypothesized that S. aureus interactions with Corynebacterium spp. diminish S. aureus virulence. We tested this by assaying for changes in S. aureus gene expression during in vitro mono- versus coculture with Corynebacterium striatum, a common skin and nasal commensal. We observed a broad shift in S. aureus gene transcription during in vitro growth with C. striatum, including increased transcription of genes known to exhibit increased expression during human nasal colonization and decreased transcription of virulence genes. S. aureus uses several regulatory pathways to transition between commensal and pathogenic states. One of these, the quorum signal accessory gene regulator (agr) system, was strongly inhibited in response to Corynebacterium spp. Phenotypically, S. aureus exposed to C. striatum exhibited increased adhesion to epithelial cells, reflecting a commensal state, and decreased hemolysin activity, reflecting an attenuation of virulence. Consistent with this, S. aureus displayed diminished fitness in experimental in vivo coinfection with C. striatum when compared to monoinfection. These data support a model in which S. aureus shifts from virulence toward a commensal state when exposed to commensal Corynebacterium species. PMID:27582729

  7. Staphylococcus aureus bacteriuria as a prognosticator for outcome of Staphylococcus aureus bacteremia: a case-control study

    Directory of Open Access Journals (Sweden)

    Weinstein Robert A

    2010-07-01

    Full Text Available Abstract Background When Staphylococcus aureus is isolated in urine, it is thought to usually represent hematogenous spread. Because such spread might have special clinical significance, we evaluated predictors and outcomes of S. aureus bacteriuria among patients with S. aureus bacteremia. Methods A case-control study was performed at John H. Stroger Jr. Hospital of Cook County among adult inpatients during January 2002-December 2006. Cases and controls had positive and negative urine cultures, respectively, for S. aureus, within 72 hours of positive blood culture for S. aureus. Controls were sampled randomly in a 1:4 ratio. Univariate and multivariable logistic regression analyses were done. Results Overall, 59% of patients were African-American, 12% died, 56% of infections had community-onset infections, and 58% were infected with methicillin-susceptible S. aureus (MSSA. Among 61 cases and 247 controls, predictors of S. aureus bacteriuria on multivariate analysis were urological surgery (OR = 3.4, p = 0.06 and genitourinary infection (OR = 9.2, p = 0.002. Among patients who died, there were significantly more patients with bacteriuria than among patients who survived (39% vs. 17%; p = 0.002. In multiple Cox regression analysis, death risks in bacteremic patients were bacteriuria (hazard ratio 2.9, CI 1.4-5.9, p = 0.004, bladder catheter use (2.0, 1.0-4.0, p = 0.06, and Charlson score (1.1, 1.1-1.3, p = 0.02. Neither length of stay nor methicillin-resistant Staphylococcus aureus (MRSA infection was a predictor of S. aureus bacteriuria or death. Conclusions Among patients with S. aureus bacteremia, those with S. aureus bacteriuria had 3-fold higher mortality than those without bacteriuria, even after adjustment for comorbidities. Bacteriuria may identify patients with more severe bacteremia, who are at risk of worse outcomes.

  8. Plasmid profile of multi antibiotic resistant staphylococcus aureus ...

    African Journals Online (AJOL)

    Plasmid profile of multi antibiotic resistant staphylococcus aureus isolated from diabetic wounds from patients at Nsukka, South-eastern, Nigeria. ... not susceptible to current antibiotics. This could suggest an imminent change in resistant pattern as observed, particularly in an area already reported as high antibiotic use.

  9. A study of Staphylococcus aureus nasal carriage, antibacterial ...

    African Journals Online (AJOL)

    Aim: This study was to determine the virulence encoding genes, and the antibiotic resistance patterns of the Staphylococcus aureus isolates, which were isolated from the nasal samples of chest clinic patients. Materials and Methods: The nasal samples of the in‑patients (431) and out‑patients (1857) in Kayseri Training and ...

  10. A study of Staphylococcus aureus nasal carriage, antibacterial ...

    African Journals Online (AJOL)

    2014-12-30

    Dec 30, 2014 ... Aim: This study was to determine the virulence encoding genes, and the antibiotic resistance patterns of the. Staphylococcus aureus isolates, which were isolated from the nasal samples of chest clinic patients. Materials and Methods: The nasal samples of the in‑patients (431) and out‑patients (1857) in ...

  11. Nasal carriage of Staphylococcus aureus among food handlers and ...

    African Journals Online (AJOL)

    Food handlers have been recognized to play a major role in the transmission of food borne diseases; contributing significantly to the global incidence and burden of the diseases. This study therefore, assesses the nasal carriage of staphylococcus aureus among food handlers and restaurant workers in Ekpoma, Edo State, ...

  12. Enterotoxicity of Staphylococcus aureus isolated from beans pudding

    African Journals Online (AJOL)

    36 samples of beans pudding from selected sources were analysed for Staphylococcus aureus and Bacillus cereus using standard protocols aimed at assessing its bacteriological quality. Samples obtained from restaurant showed slightly lower value for total plate count (1.3 x 104 - 1.6 x 106 cfu/gm) compared to samples ...

  13. Monitoring of abdominal Staphylococcus aureus infection using magnetic resonance imaging

    DEFF Research Database (Denmark)

    Kromrey, M L; Göhler, A; Friedrich, N

    2017-01-01

    To establish a routine workflow for in vivo magnetic resonance imaging (MRI) of mice infected with bacterial biosafety level 2 pathogens and to generate a mouse model for systemic infection with Staphylococcus aureus suitable for monitoring by MRI. A self-contained acrylic glass animal bed...

  14. Validation of binary typing for Staphylococcus aureus strains

    NARCIS (Netherlands)

    N. van Leeuwen; M. Heck; A.F. van Belkum (Alex); H.A. Verbrugh (Henri); W.B. van Leeuwen (Willem); J. van der Velden (Jos)

    1999-01-01

    textabstractMost of the DNA-based methods for genetic typing of Staphylococcus aureus strains generate complex banding patterns. Therefore, we have developed a binary typing procedure involving strain-differentiating DNA probes which were generated on the basis of

  15. The prevalence and resistivity pattern of Staphylococcus Aureus ...

    African Journals Online (AJOL)

    Interestingly, microbial resistance was higher for Ampicillin than Methicillin, while Tetracycline, among other antibiotics, was the most effective to both ear and nose isolates. Thus, the treatment for Staphylococcus aureus with Methicillin and other related antibiotics should be limited or controlled by susceptibility test results.

  16. Survival of Esherichia coli 0157:H7, Staphylococcus aureus ...

    African Journals Online (AJOL)

    The survival or inhibition of foodborne pathogens in different fermented products are well documented. This prompted the study to evaluate survival of Esherichia coli O157:H7, Staphylococcus aureus, Shigella flexneri and Salmonella spp. in two Ethiopian traditional fermented low-alcohol beverages, Shamita and Borde.

  17. Incidence of staphylococcus aureus in locally produced fresh milk ...

    African Journals Online (AJOL)

    This paper investigates the incidence of the bacterial organism Staphylococcus, aureus in locally produced fresh milk (nono). The fresh milk was obtained from the Damaturu main market, Yobe state of Nigeria. Petri dishes were washed and allowed to dry. They were then sterilized in hot air oven at 130°C for two hours and ...

  18. spa typing for epidemiological surveillance of Staphylococcus aureus

    NARCIS (Netherlands)

    Hallin, Marie; Friedrich, Alexander W; Struelens, Marc J; Caugant, Dominique A.

    2009-01-01

    The spa typing method is based on sequencing of the polymorphic X region of the protein A gene (spa), present in all strains of Staphylococcus aureus. The X region is constituted of a variable number of 24-bp repeats flanked by well-conserved regions. This single-locus sequence-based typing method

  19. Can mupirocin prevent methicillin-resistant Staphylococcus aureus infections?

    NARCIS (Netherlands)

    H.F.L. Wertheim (Heiman); M.C. Vos (Margreet)

    2005-01-01

    textabstractIn a retrospective study, Dr Muller and colleagues have assessed the efficacy of mupirocin nasal ointment alongside hygienic measures in methicillin-resistant Staphylococcus aureus (MRSA)-positive patients admitted to the intensive care unit (ICU). Their findings, which suggest that

  20. Low efficacy of tobramycin in experimental Staphylococcus aureus endocarditis

    DEFF Research Database (Denmark)

    Lerche, C. J.; Christophersen, L. J.; Trøstrup, H.

    2015-01-01

    The empiric treatment of infective endocarditis (IE) varies widely and, in some places, a regimen of penicillin in combination with an aminoglycoside is administered. The increasing incidence of Staphylococcus aureus IE, poor tissue penetration by aminoglycosides and low frequency of penicillin...

  1. [Staphylococcus aureus methicillin-resistant community acquired neonatal orbital cellulitis].

    Science.gov (United States)

    Pérez, M Guadalupe; Castro, Graciela; Mansilla, Celeste; Kaldzielski, Carina; Salas, Gisela; Rosanova, María Teresa; Berberian, Griselda

    2013-04-01

    Orbital cellulitis typically occurs in older children, but it can occasionally affect infants and neonates. Staphylococcus aureus is the main pathogen isolated. Outcome depends on an adequate initial approach. We report three neonates with orbital cellulitis caused by community-associated MRSA.

  2. Binding of Staphylococcus aureus onto bovine intestinal mucin ...

    African Journals Online (AJOL)

    Mucins act as protection for the gastrointestinal tract against various invading organisms. They are also crucial in developing drugs against these organisms as well as other therapeutic purposes. This study was carried out to investigate the binding of Staphylococcus aureus onto bovine intestinal mucin in vitro. The isolate ...

  3. Efficacy of extended cefquinome treatment of clinical Staphylococcus aureus mastitis

    NARCIS (Netherlands)

    Swinkels, J. M.; Cox, P.; Schukken, Y. H.; Lam, T. J G M|info:eu-repo/dai/nl/14686820X

    2013-01-01

    Clinical Staphylococcus aureus mastitis is difficult to cure. Extended antimicrobial treatment is often advocated as a practical approach to improve cure rates; however, scientific evidence of this hypothesis is lacking. A multi-centered, nonblinded, randomized, positive-controlled clinical trial

  4. Pyrazole Based Inhibitors against Enzymes of Staphylococcus aureus

    DEFF Research Database (Denmark)

    Jagadeesan, G.; Vijayakuma, Vinodhkumar; Palayam, Malathy

    2015-01-01

    agents. The current study focuses on molecular docking and dynamics studies of pyrazole derivatives against Nucleosidase and DNA gyrase B of Staphylococcus aureus. Molecular docking and dynamics studies reveal that some of these derivatives show better binding abilities than some of the current drugs...

  5. Increased risk of arterial thromboembolic events after Staphylococcus aureus bacteremia

    DEFF Research Database (Denmark)

    Mejer, N; Gotland, N; Uhre, M L

    2015-01-01

    OBJECTIVES: An association between infection and arterial thromboembolic events (ATE) has been suggested. Here we examined the risk of myocardial infarction (MI), stroke and other ATE after Staphylococcus aureus bacteremia (SAB). METHODS: Danish register-based nation-wide observational cohort study...

  6. Genetic variation and relationship in Staphylococcus aureus isolates ...

    African Journals Online (AJOL)

    A genetic characterization of 18 different isolates of Staphylococcus aureus using random amplified polymorphic DNAs (RAPDs) was carried out. Out of one hundred primers tested, ten showed polymorphism. The amplification reactions with the 10 primers generated 88 bands, 51 of which is polymorphic with band size ...

  7. Multiple drug resistance Staphylococcus aureus isolated in foods of ...

    African Journals Online (AJOL)

    Background: StaphylococcuS. aureus is the most important agent, which is known to cause a wide range of diseases in both human and animals. Extended use and misuse of antibiotics in agriculture, stock farming and in the treatment of human diseases, has contributed to the rapid increase of the number of bacteria that ...

  8. An Interdisciplinary Experiment: Azo-Dye Metabolism by "Staphylococcus Aureus"

    Science.gov (United States)

    Brocklesby, Kayleigh; Smith, Robert; Sharp, Duncan

    2012-01-01

    An interdisciplinary and engaging practical is detailed which offers great versatility in the study of a qualitative and quantitative metabolism of azo-dyes by "Staphylococcus aureus". This practical has broad scope for adaptation in the number and depth of variables to allow a focused practical experiment or small research project. Azo-dyes are…

  9. Microstructures as IR-sensors with Staphylococcus aureus bacteria

    Science.gov (United States)

    Baikova, T. V.; Danilov, P. A.; Gonchukov, S. A.; Yermachenko, V. M.; Ionin, A. A.; Khmelnitskii, R. A.; Kudryashov, S. I.; Nguyen, T. T. H.; Rudenko, A. A.; Saraeva, I. N.; Svistunova, T. S.; Zayarny, D. A.

    2017-09-01

    Using a micro-hole grating in a supported silver film as a laser-fabricated novel optical platform for surface-enhanced IR absoprtion/reflection spectroscopy, characteristic absorption bands of Staphylococcus aureus, especially - its buried carotenoid fragments - were detected in FT-IR spectra with 10-fold analytical enhancement, paving the way to spectral express-identification of the pathogenic microorganisms.

  10. Natural Population Dynamics and Carriage of Staphylococcus aureus

    NARCIS (Netherlands)

    D.C. Melles (Damian)

    2008-01-01

    textabstractStaphylococcus aureus is a major human pathogen capable of causing a wide range of infections, from relatively mild skin infections such as folliculitis and furunculosis to life-threatening conditions, including sepsis, deep abscesses, pneumonia, osteomyelitis, and infective endocarditis

  11. Global initiative for meticillin-resistant Staphylococcus aureus pneumonia (GLIMP)

    DEFF Research Database (Denmark)

    Aliberti, Stefano; Reyes, Luis F; Faverio, Paola

    2016-01-01

    BACKGROUND: Antibiotic resistance is a major global health problem and pathogens such as meticillin-resistant Staphylococcus aureus (MRSA) have become of particular concern in the management of lower respiratory tract infections. However, few data are available on the worldwide prevalence and ris...

  12. Methicillin-Resistant Staphylococcus aureus, Geneva, Switzerland, 1993–2005

    Science.gov (United States)

    Harbarth, Stephan; Huyghe, Antoine; Renzi, Gesuele; Bento, Manuela; Gervaix, Alain; Pittet, Didier; Schrenzel, Jacques

    2008-01-01

    Molecular characterization of methicillin-resistant Staphylococcus aureus (MRSA) strains different from those of an endemic healthcare-associated clone was conducted over 13 years in Geneva, Switzerland. We demonstrated strain diversity, including clones rarely found in Europe. Local epidemiology of community-associated MRSA is diverse and is evolving by importation and transmission of new strains. PMID:18258126

  13. Antibiotic sensitivity pattern of Staphylococcus aureus from clinical ...

    African Journals Online (AJOL)

    Background: The importance of Staphylococcus aureus as a persistent nosocomial and community acquired pathogen has become a global health concern. It has a remarkable capability of evolving different mechanisms of resistance to most antimicrobial agents. The aim of the present study is to establish the incidence of ...

  14. Methicilin-resistant Staphylococcus aureus (MRSA) at Jos University ...

    African Journals Online (AJOL)

    A prospective surveillance of Methicillin resistant staphylococcus aureus (MRSA) was carried out at Jos University Teaching Hospital, Nigeria, over a one year period. This study highlights the continuos importance of MRSA in causing both hospital and to a less extent community acquired infections. Out of the 180 ...

  15. Prevalence of methicillin-resistant Staphylococcus aureus and ...

    African Journals Online (AJOL)

    Wound colonization by microorganisms is most frequently polymicrobial and incidences of high level resistance among bacterial isolates from wounds have been reported. Methicillin-resistant Staphylococcus aureus (MRSA) and extendedspectrum beta-lactamase (ESBL) producing Gram-negative bacteria both constitute ...

  16. Methicillin resistance in Staphylococcus aureus : a review of the ...

    African Journals Online (AJOL)

    BACKGROUND: Despite the volume of knowledge, enhanced surveillance and infection control measures adopted by health care institutions to address the endemicity and frequent disease outbreaks by methicillin-resistant Staphylococcus aureus (MRSA) in hospitals and health care facilities worldwide, infections due to ...

  17. Pitfalls in the routine diagnosis of Staphylococcus aureus | Bello ...

    African Journals Online (AJOL)

    Two hundred isolates of Presumed Staphylococcus aureus from routine clinical specimens, collected from two government hospitals in Abha, Saudi Arabia, had their identity verified. We used the tube coagulase test as our gold standard. Twenty (10%) of the isolates were mis-identified. Reliance by the two laboratories on ...

  18. Prevalence and risk factors for Staphylococcus aureus and ...

    African Journals Online (AJOL)

    2015-09-05

    Sep 5, 2015 ... Introduction. Staphylococcus aureus may cause serious skin and soft tissue infections, the bacteria can also infect any tissue of the body, causing other serious or life‑threating diseases, such as deep abscesses, endocarditis, osteomyelitis, pneumonia, and sepsis.[1] Emergence and spread of antimicrobial.

  19. Staphylococcus aureus in mastitic crossbreed cows and its ...

    African Journals Online (AJOL)

    The occurrence of bovine mastitis associated with Staphylococcus aureus varied significantly (p<0.05) between breed, lactation stage, parity and age. It was higher (n= 49, 56.9%) in Zebu-Jersey than Zebu-Holstein Frisian (n= 25, 37.3%) crossbred cows. Staphyloccocal mastitis is a major health problem in dairy farm of ...

  20. Surveillance van meticilline resistente Staphylococcus aureus in Nederland in 1990

    NARCIS (Netherlands)

    Frenay HME; van Leeuwen WJ; van Klingeren B; Rost JA; Schot CS

    1991-01-01

    Follow-up studies on the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in Dutch hospitals were continued in 1990. The number of MRSA-isolates in 1990 compared to 1989 is approximately the same. Phage-type pattern and antibiogram were determined for 168 MRSA-isolates from 42

  1. Misidentification of methicillinresistant Staphylococcus aureus (MRSA)

    African Journals Online (AJOL)

    , 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 ...

  2. Antimicrobial Resistance Pattern and Minimum Inhibitory Concentration of Vancomycin among Staphylococcus aureus and Coagulase-Negative Staphylococci Isolated from Clinical Specimens of Children in Tabriz

    Directory of Open Access Journals (Sweden)

    Shahram Abdoli Oskouie

    2013-04-01

    Full Text Available Background & Objectives: Staphylococci are among common causes of community acquired and nosocomial infections around the world. Over the last decade, the resistance of these bacteria in hospital environments is increasing to various antibiotics such as vancomycin. The aim of present study was to determine the antimicrobial resistance pattern and Minimum Inhibitory Concentration (MIC values among a clinical collection of staphylococci isolated from hospitalized children in Tabriz.   Methods: In this prospective and descriptive study, 88 staphylococcal isolates including 53 S. aureus and 35 coagulase-negative staphylococcus species were recovered from various clinical specimens referred to microbiology laboratory of Children Hospital during study period (April 2011 to March 2012. Susceptibility of the isolates against 15 different antimicrobial agents and MIC values of vancomycin was tested using standard disk diffusion and E-test methods respectively.   Results: According to the results of drug susceptibility testing, vancomycin and rifampin were the most effective but clindamycin and penicillin were the least effective drugs against tested isolates. Accordingly, the prevalence of methicillin resistant Staphylococcus aureus (MRSA strains was determined more than 80%. According to MIC values, 13.2% of S. aureus and 3.3% of coagulase-negative staphylococcus isolates showed intermediate resistance to vancomycin. None of the isolates was fully resistant to vancomycin isolates in this study.   Conclusion: Although fully vancomycin resistant staphylococci was not found among tested isolates in this study, there was VISA strains. Since there are reports on the emergence of VRSA strains from Iran and other countries, it is necessary for the clinician to care in prescription of vancomycin as a selective drug against staphylococcal infections. Moreover, the necessity of MIC measurement in determining of vancomycin susceptibility is more apparent.

  3. Nasal carriage of Staphylococcus aureus among healthy adults.

    Science.gov (United States)

    Choi, Chong Seng; Yin, Chow Suet; Bakar, Afra Abu; Sakewi, Zamberi; Naing, Nyi Nyi; Jamal, Farida; Othman, Norlijah

    2006-12-01

    Data on the carriage rate and antibiotic sensitivity pattern of Staphylococcus aureus strains prevalent in the community are not available for many developing countries including Malaysia. To estimate the extent of community S. aureus transmission, in particular methicillin-resistant S. aureus (MRSA), the prevalence of S. aureus nasal colonization in a population of healthy adults was determined. Factors associated with S. aureus nasal carriage and antibiotic sensitivity patterns of the isolates were also analyzed. A cross-sectional study involving 346 adults was conducted. Nasal swabs were examined for the presence of S. aureus. Epidemiological information concerning risk factors for nasal carriage was also obtained. Antibiotic susceptibility testing was performed using the disk diffusion method according to the National Committee for Clinical Laboratory Standards guidelines. MRSA strains isolated were further subjected to pulse-field gel electrophoresis analysis. The prevalence of S. aureus nasal carriage was 23.4%. The findings also revealed that ex-smokers (95% confidence interval [CI] 1.08-6.32, p=0.033) and oral contraceptive users (95% CI 1.12-21.67, p=0.035) were more likely to harbor S. aureus. One person was colonized with MRSA, which was different from the hospital strain. MRSA nasal colonization was found to be low outside of the health care environment. Smokers and oral contraceptive users have high nasal carrier rates.

  4. Staphylococcus aureus strategies to evade the host acquired immune response.

    Science.gov (United States)

    Goldmann, Oliver; Medina, Eva

    2017-09-15

    Staphylococcus aureus poses a significant public-health problem. Infection caused by S. aureus can manifest as acute or long-lasting persistent diseases that are often refractory to antibiotic and are associated with significant morbidity and mortality. To develop more effective strategies for preventing or treating these infections, it is crucial to understand why the immune response is incapable to eradicate the bacterium. When S. aureus first infect the host, there is a robust activation of the host innate immune responses. Generally, S. aureus can survive this initial interaction due to the expression of a wide array of virulence factors that interfere with the host innate immune defenses. After this initial interaction the acquired immune response is the arm of the host defenses that will try to clear the pathogen. However, S. aureus is capable of maintaining infection in the host even in the presence of a robust antigen-specific immune response. Thus, understanding the mechanisms underlying the ability of S. aureus to escape immune surveillance by the acquired immune response will help uncover potentially important targets for the development of immune-based adjunctive therapies and more efficient vaccines. There are several lines of evidence that lead us to believe that S. aureus can directly or indirectly disable the acquired immune response. This review will discuss the different immune evasion strategies used by S. aureus to modulate the different components of the acquired immune defenses. Copyright © 2017 Elsevier GmbH. All rights reserved.

  5. Duplex Identification of Staphylococcus aureus by Aptamer and Gold Nanoparticles.

    Science.gov (United States)

    Chang, Tianjun; Wang, Libo; Zhao, Kexu; Ge, Yu; He, Meng; Li, Gang

    2016-06-01

    Staphylococcus aureus is the top common pathogen causing infections and food poisoning. Identification of S. aureus is crucial for the disease diagnosis and regulation of food hygiene. Herein, we report an aptamer-AuNPs based method for duplex identification of S. aureus. Using AuNPs as an indicator, SA23, an aptamer against S. aureus, can well identify its target from Escherichia coli, Listeria monocytogenes and Pseudomonas aeruginosa. Furthermore, we find citrate-coated AuNPs can strongly bind to S. aureus, but not bind to Salmonella enterica and Proteus mirabilis, which leads to different color changes in salt solution. This colorimetric response is capable of distinguishing S. aureus from S. enteritidis and P. mirabilis. Thus, using the aptasensor and AuNPs together, S. aureus can be accurately identified from the common pathogens. This duplex identification system is a promising platform for simple visual identification of S. aureus. Additionally, in the aptasensing process, bacteria are incubated with aptamers and then be removed before the aptamers adding to AuNPs, which may avoid the interactions between bacteria and AuNPs. This strategy can be potentially applied in principle to detect other cells by AuNPs-based aptasensors.

  6. Maternal-neonatal outcome with Staphylococcus aureus rectovaginal colonization.

    Science.gov (United States)

    Ghanim, Nibal; Alchyib, Omrou; Morrish, Donald; Tompkins, David; Julliard, Kell; Visconti, Ernest; Hoskins, Iffath A

    2011-01-01

    To estimate prevalence of rectovaginal colonization by Staphylococcus aureus among pregnant women with group B streptococcus (GBS) screening results and its association with maternal and infant outcomes. Cultures that detected both group B streptococcus (GBS) and S. aureus were obtained at > or = 35 weeks of gestation. Computerized database search and chart review determined invasive neonatal infection and maternal outcomes at the time of delivery through 6 months postpartum. A total of 6,626 GBS screening cultures met study criteria, and 769 (11.6%) GBS isolates and 67 (1.0%) S. aureus were identified. No maternal S. aureus-related outcomes were found. The rate of maternal methicillin-resistant S. aureus colonization was 0.1% (7 in 6,626). GBS-positive patients were twice as likely to be colonized with methicillin-susceptible S. aureus than GBS-negative patients. GBS-positive culture rates differed significantly by primary language: Spanish 10.0%, English 13.7%, Russian 26.9%, Cantonese 13.2%, Mandarin 11.5%, Arabic 15.9%, and other 17.8%. In our population, S. aureus colonization percentage (1.0%) was lower than the 7.5-8.2% reported by other medical centers, as was overall GBS carriage rate. S. aureus did not predispose to maternal or infant morbidity or mortality up to 6 months postpartum.

  7. Vancomycin-Resistant Enterococci (VRE):Overview

    Science.gov (United States)

    ... While enterococci are not as familiar as staphylococcus (staph) or Escherichia coli ( E. coli ) bacteria, enterococci infections ... are much less capable of causing disease than staph or E. coli but still can complicate and ...

  8. Staphylococcus aureus and the ecology of the nasal microbiome

    Science.gov (United States)

    Liu, Cindy M.; Price, Lance B.; Hungate, Bruce A.; Abraham, Alison G.; Larsen, Lisbeth A.; Christensen, Kaare; Stegger, Marc; Skov, Robert; Andersen, Paal Skytt

    2015-01-01

    The human microbiome can play a key role in host susceptibility to pathogens, including in the nasal cavity, a site favored by Staphylococcus aureus. However, what determines our resident nasal microbiota—the host or the environment—and can interactions among nasal bacteria determine S. aureus colonization? Our study of 46 monozygotic and 43 dizygotic twin pairs revealed that nasal microbiota is an environmentally derived trait, but the host’s sex and genetics significantly influence nasal bacterial density. Although specific taxa, including lactic acid bacteria, can determine S. aureus colonization, their negative interactions depend on thresholds of absolute abundance. These findings demonstrate that nasal microbiota is not fixed by host genetics and opens the possibility that nasal microbiota may be manipulated to prevent or eliminate S. aureus colonization. PMID:26601194

  9. Truncated Autoinducing Peptide Conjugates Selectively Recognize and Kill Staphylococcus aureus.

    Science.gov (United States)

    Tsuchikama, Kyoji; Shimamoto, Yasuhiro; Anami, Yasuaki

    2017-06-09

    The accessory gene regulator (agr) of Staphylococcus aureus coordinates various pathogenic events and is recognized as a promising therapeutic target for virulence control. S. aureus utilizes autoinducing peptides (AIPs), cyclic-peptide signaling molecules, to mediate the agr system. Despite the high potency of synthetic AIP analogues in agr inhibition, the potential of AIP molecules as a delivery vehicle for antibacterial agents remains unexplored. Herein, we report that truncated AIP scaffolds can be fused with fluorophore and cytotoxic photosensitizer molecules without compromising their high agr inhibitory activity, binding affinity to the receptor AgrC, or cell specificity. Strikingly, a photosensitizer-AIP conjugate exhibited 16-fold greater efficacy in a S. aureus cell-killing assay than a nontargeting analogue. These findings highlight the potential of truncated AIP conjugates as useful chemical tools for in-depth biological studies and as effective anti-S. aureus agents.

  10. Simple method for correct enumeration of Staphylococcus aureus

    DEFF Research Database (Denmark)

    Haaber, J.; Cohn, M. T.; Petersen, A.

    2016-01-01

    culture. When grown in such liquid cultures, the human pathogen Staphylococcus aureus is characterized by its aggregation of single cells into clusters of variable size. Here, we show that aggregation during growth in the laboratory standard medium tryptic soy broth (TSB) is common among clinical...... and laboratory S. aureus isolates and that aggregation may introduce significant bias when applying standard enumeration methods on S. aureus growing in laboratory batch cultures. We provide a simple and efficient sonication procedure, which can be applied prior to optical density measurements to give...... an accurate estimate of cellular numbers in liquid cultures of S. aureus regardless of the aggregation level of the given strain. We further show that the sonication procedure is applicable for accurate determination of cell numbers using agar plate counting of aggregating strains....

  11. Methicillin-resistant Staphylococcus aureus adaptation to human keratinocytes.

    Science.gov (United States)

    Soong, Grace; Paulino, Franklin; Wachtel, Sarah; Parker, Dane; Wickersham, Matthew; Zhang, Dongni; Brown, Armand; Lauren, Christine; Dowd, Margaret; West, Emily; Horst, Basil; Planet, Paul; Prince, Alice

    2015-04-21

    Skin is the most common site of Staphylococcus aureus infection. While most of these infections are self-limited, recurrent infections are common. Keratinocytes and recruited immune cells participate in skin defense against infection. We postulated that S. aureus is able to adapt to the milieu within human keratinocytes to avoid keratinocyte-mediated clearance. From a collection of S. aureus isolated from chronically infected patients with atopic dermatitis, we noted 22% had an agr mutant-like phenotype. Using several models of human skin infection, we demonstrate that toxin-deficient, agr mutants of methicillin-resistant S. aureus (MRSA) USA300 are able to persist within keratinocytes by stimulating autophagy and evading caspase-1 and inflammasome activation. MRSA infection induced keratinocyte autophagy, as evidenced by galectin-8 and LC3 accumulation. Autophagy promoted the degradation of inflammasome components and facilitated staphylococcal survival. The recovery of more than 58% agr or RNAIII mutants (P Soong et al.

  12. Molecular characteristics of methicillin-resistant Staphylococcus aureus (MRSA) strains isolated from patients with bacteremia based on MLST, SCCmec, spa, and agr locus types analysis.

    Science.gov (United States)

    Goudarzi, Mehdi; Seyedjavadi, Sima Sadat; Nasiri, Mohammad Javad; Goudarzi, Hossein; Sajadi Nia, Raheleh; Dabiri, Hossein

    2017-03-01

    The widespread emergence of methicillin resistant Staphylococcus aureus, as a common cause of nosocomial infections, is becoming a serious concern in global public health. The objective of the present study was to investigate antimicrobial susceptibility pattern, frequency of virulence genes and molecular characteristics of methicillin-resistant Staphylococcus aureus strains isolated from patients with bacteremia. A total of 128 methicillin-resistant Staphylococcus aureus isolates were collected during February 2015 to January 2016. In vitro antimicrobial susceptibility of the isolates was assessed using the disk diffusion method. Conventional PCR was performed for the detection of adhesion (can, bbp, ebp, fnbB, fnbA, clfB, clfA) and toxin (etb, eta, pvl, tst) encoding genes, determining the agr type, SCCmec, MLST and spa typing of the isolates. All the methicillin-resistant Staphylococcus aureus isolates were found to be sensitive to linezolid, teicoplanin, and vancomycin. Resistance to the tested antibiotics varied from 97.7% for penicillin to 24.2% for mupirocin. The rate of multi drug resistance (MDR) in the present study was 97.7%. The most commonly detected toxin and adhesion genes were tst (58.6%), and clfB (100%), respectively. The majority of SCCmec III isolates were found in agr group I while SCCmec IV and II isolates were distributed among agr group III. Multilocus Sequence Typing (MLST) of the MRSA isolates showed five different sequence types: ST239 (43%), ST22 (39.8%), ST585 (10.9%), ST45 (3.9%) and ST240 (2.3%). All of the pvl positive strains belonged to ST22-SCCmec IV/t790 clone and were MDR. Among different 7 spa types, the most common were t790 (27.3%), t037 (21.9%), and t030 (14.1%). spa types t016, t924 and spa type t383 were reported for the first time from Asia and Iran, respectively. It was shown that spa types circulating in the studied hospitals varied which support the need to perform future surveillance studies in order to understand

  13. Problems with rapid agglutination methods for identification of Staphylococcus aureus when Staphylococcus saprophyticus is being tested.

    OpenAIRE

    Gregson, D B; Low, D E; Skulnick, M; Simor, A E

    1988-01-01

    Six rapid agglutination tests for identification of Staphylococcus aureus were evaluated by using 62 strains of S. aureus, 63 strains of S. saprophyticus, and 67 strains of other coagulase-negative staphylococci. S. saprophyticus was responsible for 19 of 26 false-positive results and 20 uninterpretable reactions. Thus, urinary staphylococcal isolates that are positive by rapid agglutination tests may require other confirmatory tests for the identification of possible S. saprophyticus.

  14. Human Staphylococcus aureus lineages among Zoological Park ...

    African Journals Online (AJOL)

    Clones were defined by Multilocus Sequence Typing (MLST), spa type and Pulsed-Field Gel Electrophoresis (PFGE). Seven S. aureus isolates were recovered from four animals and one from an employee. All were mecA, mecC and tst–negative, whereas, one carried the PVL genes and was isolated from an infected ...

  15. Resistance patterns of Staphylococcus aureus and Pseudomonas ...

    African Journals Online (AJOL)

    Two hundred (200) strains of S. aureus and P. aeruginosa were isolated from clinical samples collected from patients in Murtala Muhammad Specialist Hospital and Infectious Diseases Hospital, Kano. The confirmed isolates were tested for resistance to quinolones by the agar disk diffusion susceptibility test and the agar ...

  16. Staphylococcus aureus infections; Lead by the nose

    NARCIS (Netherlands)

    H.F.L. Wertheim (Heiman)

    2005-01-01

    textabstractAn overview and the latest insights regarding S. aureus nasal carriage, associated risks of developing infections and possible preventive measures, will be given in Chapter 2. Since mupirocin efficacy studies in preventing nosocomial infections have only been performed in surgical and

  17. Vancomycin-resistant enterococci: validation of susceptibility testing and in vitro activity of novel antibiotics

    DEFF Research Database (Denmark)

    Rathe, Mathias; Lise, Kristensen,; Ellermann-Eriksen, Svend

    Vancomycin-resistant enterococci: validation of susceptibility testing and in vitro activity of novel antibiotics......Vancomycin-resistant enterococci: validation of susceptibility testing and in vitro activity of novel antibiotics...

  18. A cohort study of the Copenhagen CF Centre eradication strategy against Staphylococcus aureus in patients with CF

    DEFF Research Database (Denmark)

    Dalbøge, Christina Schjellerup; Pressler, Tacjana; Høiby, Niels

    2013-01-01

    Staphylococcus aureus is an important pathogen in CF. Centre prevalence of intermittent colonization and chronic S. aureus infections and the effectiveness of an anti-S. aureus eradication strategy was assessed.......Staphylococcus aureus is an important pathogen in CF. Centre prevalence of intermittent colonization and chronic S. aureus infections and the effectiveness of an anti-S. aureus eradication strategy was assessed....

  19. Effect of proteases against biofilms of Staphylococcus aureus and Staphylococcus epidermidis.

    Science.gov (United States)

    Elchinger, P-H; Delattre, C; Faure, S; Roy, O; Badel, S; Bernardi, T; Taillefumier, C; Michaud, P

    2014-11-01

    Biofilms play a key role in bacterial resistance against antibacterial agents-an issue that causes multiple problems in medical fields, particularly with Staphylococcus biofilms that colonize medical indwelling devices. The literature reports several anti-biofilm strategies that have been applied in medicine. Disrupting the biofilm formation process creates new sites open to colonization by treatment-generated planktonic bacteria, so efforts have turned to focus on strategies to prevent and control the initial Staphylococci adhesion. Here, we investigated the preventive activities of three commercial proteases (Flavourzyme, Neutrase and Alcalase) against biofilm formation by two Staphylococcus strains. Some proteolytic extracts revealed interesting results with Staphylococcus epidermidis and Staphylococcus aureus aureus biofilms. Three proteases were tested against Staphylococcus aureus and Staphylococcus epidermidis biofilms in standard conditions. The Flavourzyme containing a mix of Aspergillus orizae endo- and exoproteases demonstrated significant efficacy against Staph. epidermidis biofilm formation. These results could prove valuable in the effort to develop simple anti-biofilm methods. © 2014 The Society for Applied Microbiology.

  20. Staphylococcus aureus infections following knee and hip prosthesis insertion procedures.

    Science.gov (United States)

    Arduino, Jean Marie; Kaye, Keith S; Reed, Shelby D; Peter, Senaka A; Sexton, Daniel J; Chen, Luke F; Hardy, N Chantelle; Tong, Steven Yc; Smugar, Steven S; Fowler, Vance G; Anderson, Deverick J

    2015-01-01

    Staphylococcus aureus is the most common and most important pathogen following knee and hip arthroplasty procedures. Understanding the epidemiology of invasive S. aureus infections is important to quantify this serious complication. This nested retrospective cohort analysis included adult patients who had undergone insertion of knee or hip prostheses with clean or clean-contaminated wound class at 11 hospitals between 2003-2006. Invasive S. aureus infections, non-superficial incisional surgical site infections (SSIs) and blood stream infections (BSIs), were prospectively identified following each procedure. Prevalence rates, per 100 procedures, were estimated. 13,719 prosthetic knee (62%) and hip (38%) insertion procedures were performed. Of 92 invasive S. aureus infections identified, SSIs were more common (80%) than SSI and BSI (10%) or BSI alone (10%). The rate of invasive S. aureus infection/100 procedures was 0.57 [95% CI: 0.43-0.73] for knee insertion and 0.83 [95% CI: 0.61-1.08] for hip insertion. More than half (53%) were methicillin-resistant. Median time-to-onset of infection was 34 and 26 days for knee and hip insertion, respectively. Infection was associated with higher National Healthcare Safety Network risk index (p ≤ 0.0001). Post-operative invasive S. aureus infections were rare, but difficult-to-treat methicillin-resistant infections were relatively common. Optimizing preventative efforts may greatly reduce the healthcare burden associated with S. aureus infections.

  1. Epic Immune Battles of History: Neutrophils vs. Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Fermin E. Guerra

    2017-06-01

    Full Text Available Neutrophils are the most abundant leukocytes in human blood and the first line of defense after bacteria have breached the epithelial barriers. After migration to a site of infection, neutrophils engage and expose invading microorganisms to antimicrobial peptides and proteins, as well as reactive oxygen species, as part of their bactericidal arsenal. Ideally, neutrophils ingest bacteria to prevent damage to surrounding cells and tissues, kill invading microorganisms with antimicrobial mechanisms, undergo programmed cell death to minimize inflammation, and are cleared away by macrophages. Staphylococcus aureus (S. aureus is a prevalent Gram-positive bacterium that is a common commensal and causes a wide range of diseases from skin infections to endocarditis. Since its discovery, S. aureus has been a formidable neutrophil foe that has challenged the efficacy of this professional assassin. Indeed, proper clearance of S. aureus by neutrophils is essential to positive infection outcome, and S. aureus has developed mechanisms to evade neutrophil killing. Herein, we will review mechanisms used by S. aureus to modulate and evade neutrophil bactericidal mechanisms including priming, activation, chemotaxis, production of reactive oxygen species, and resolution of infection. We will also highlight how S. aureus uses sensory/regulatory systems to tailor production of virulence factors specifically to the triggering signal, e.g., neutrophils and defensins. To conclude, we will provide an overview of therapeutic approaches that may potentially enhance neutrophil antimicrobial functions.

  2. Silver nanoparticles for the inhibition of Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Miguel Ángel Ortiz-Gila

    2015-01-01

    Full Text Available Existe un gran ecosistema microbiano en la cavidad oral donde Staphylococcus aureus ( S. aureus se puede encontrar, causando patologías orales tales como quelitis angular, las paperas y la mucositis estafilocócica. Estas enfermedades producidas por S. aureus en la cavidad oral son consecuencia de los factores de virulencia, toxinas y multiresistencia a los antibióticos, lo que contribuye a la infección. La colonización en la cavidad oral por S. aureus en pacientes sanos es de 24% a 36%. Sin embargo, la incidencia aumenta a 48% en pacientes con prótesis debido a la formación de biofilms en la superficie de las dentaduras postizas. Actualmente, no existe ningún tratamiento para infecciones orales sin el uso de antibióticos. Investigaciones recientes indican que las nanopartículas de plata (AgNPs son un material o estrategia para eliminar S. aureus debido a su efecto antibacteriano. Sin embargo, el mecanismo del efecto inhibidor de los iones de Ag sobre S. aureus es sólo parcialmente conocida y muy poco se ha informado. Por lo tanto, el propósito de la presente revisión sistemática es determinar las estrategias y retos de la utilización de biomateriales antimicrobianos con AgNPs frente a las infecciones orales de S. aureus.

  3. [Eradication of Staphylococcus aureus in carrier patients undergoing joint arthroplasty].

    Science.gov (United States)

    Barbero Allende, José M; Romanyk Cabrera, Juan; Montero Ruiz, Eduardo; Vallés Purroy, Alfonso; Melgar Molero, Virginia; Agudo López, Rosa; Gete García, Luis; López Álvarez, Joaquín

    2015-02-01

    Prosthetic joint infection (PJI) is a complication with serious repercussions and its main cause is Staphylococcus aureus. The purpose of this study is to determine whether decolonization of S.aureus carriers helps to reduce the incidence of PJI by S.aureus. An S.aureus screening test was performed on nasal carriers in patients undergoing knee or hip arthroplasty between January and December 2011. Patients with a positive test were treated with intranasal mupirocin and chlorhexidine soap 5 days. The incidence of PJI was compared with patients undergoing the same surgery between January and December 2010. A total of 393 joint replacements were performed in 391 patients from the control group, with 416 joint replacements being performed in the intervention group. Colonization study was performed in 382 patients (91.8%), of which 102 were positive (26.7%) and treated. There was 2 PJI due S.aureus compared with 9 in the control group (0.5% vs 2.3%, odds ratio [OR]: 0.2, 95% confidence interval [CI]: 0.4 to 2.3, P=.04). In our study, the detection of colonization and eradication of S.aureus carriers achieved a significant decrease in PJI due to S.aureus compared to a historical group. Copyright © 2013 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

  4. The changing epidemiology of Staphylococcus aureus bloodstream infection

    DEFF Research Database (Denmark)

    Laupland, K.B.; Lyytikäinen, O.; Søgaard, Mette

    2013-01-01

    Clin Microbiol Infect ABSTRACT: Although the epidemiology of Staphylococcus aureus bloodstream infection (BSI) has been changing, international comparisons are lacking. We sought to determine the incidence of S. aureus BSI and assess trends over time and by region. Population-based surveillance...... episodes of S. aureus BSI were identified. The overall annual incidence rate for S. aureus BSI was 26.1 per 100 000 population, and those for methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) were 24.2 and 1.9 per 100 000, respectively. Although the overall incidence...... of community-onset MSSA BSI (15.0 per 100 000) was relatively similar across regions, the incidence rates of hospital-onset MSSA (9.2 per 100 000), community-onset MRSA (1.0 per 100 000) and hospital-onset MRSA (0.8 per 100 000) BSI varied substantially. Whereas the overall incidence of S. aureus BSI did...

  5. Epic Immune Battles of History: Neutrophils vs. Staphylococcus aureus

    Science.gov (United States)

    Guerra, Fermin E.; Borgogna, Timothy R.; Patel, Delisha M.; Sward, Eli W.; Voyich, Jovanka M.

    2017-01-01

    Neutrophils are the most abundant leukocytes in human blood and the first line of defense after bacteria have breached the epithelial barriers. After migration to a site of infection, neutrophils engage and expose invading microorganisms to antimicrobial peptides and proteins, as well as reactive oxygen species, as part of their bactericidal arsenal. Ideally, neutrophils ingest bacteria to prevent damage to surrounding cells and tissues, kill invading microorganisms with antimicrobial mechanisms, undergo programmed cell death to minimize inflammation, and are cleared away by macrophages. Staphylococcus aureus (S. aureus) is a prevalent Gram-positive bacterium that is a common commensal and causes a wide range of diseases from skin infections to endocarditis. Since its discovery, S. aureus has been a formidable neutrophil foe that has challenged the efficacy of this professional assassin. Indeed, proper clearance of S. aureus by neutrophils is essential to positive infection outcome, and S. aureus has developed mechanisms to evade neutrophil killing. Herein, we will review mechanisms used by S. aureus to modulate and evade neutrophil bactericidal mechanisms including priming, activation, chemotaxis, production of reactive oxygen species, and resolution of infection. We will also highlight how S. aureus uses sensory/regulatory systems to tailor production of virulence factors specifically to the triggering signal, e.g., neutrophils and defensins. To conclude, we will provide an overview of therapeutic approaches that may potentially enhance neutrophil antimicrobial functions. PMID:28713774

  6. Occurrence and distribution of Staphylococcus aureus lineages among zoo animals

    DEFF Research Database (Denmark)

    Gongora, Carmen Espinosa; Chrobak, Dorota; Moodley, Arshnee

    2012-01-01

    The current knowledge of the occurrence and diversity of Staphylococcus aureus in animals is largely biased in favour MRSA and domestic animals. In order to generate novel information on the ecology and population structure of this bacterial species in the animal kingdom, we investigated the occu...... MSSA belonging to fourteen spa types, including three novel spa types. MLST revealed the occurrence of seven STs. The study of the ecology of commensal S. aureus in captive wild animals revealed that ST133 has a broader host range than previously thought.......The current knowledge of the occurrence and diversity of Staphylococcus aureus in animals is largely biased in favour MRSA and domestic animals. In order to generate novel information on the ecology and population structure of this bacterial species in the animal kingdom, we investigated...... the occurrence and genotypic diversity of S. aureus in a range of animal species kept at the Copenhagen Zoo. We sampled 146 animals belonging to 25 mammalian species and 21 reptiles belonging to six species. A total of 59 S. aureus isolates were found in 10 of the 25 mammalian species tested. All isolates were...

  7. Staphylococcus aureus isolated from tonsillectomized adult patients with recurrent tonsillitis.

    Science.gov (United States)

    Katkowska, Marta; Garbacz, Katarzyna; Stromkowski, Józef

    2017-01-01

    The aim of this study was to analyze the prevalence and antibiotic resistance of Staphylococcus aureus strains from 118 tonsillectomized adults due to recurrent tonsillitis (RT). The study included strains isolated from the tonsillar surface prior to tonsillectomy, recovered from the tonsillar core at the time of surgery, and from the posterior throat 2-4 weeks after the procedure. Susceptibility of isolates to 19 antibiotics was tested in line with the Clinical and Laboratory Standards Institute recommendations. Irrespective of the stage, the most commonly isolated bacteria were gram-positive cocci, and among them S. aureus. The tonsillar core was the most common site of S. aureus isolation (30.5%), followed by the tonsillar surface (10.8%) and the posterior pharynx (5.9%). This difference turned out to be statistically significant (p Staphylococcus aureus seems to be the most common pathogen isolated from patients tonsillectomized due to RT. Staphylococcal isolates associated with RT are present mostly within the tonsillar core and susceptible to most antibiotics. They are typically isolated from patients between 21 and 30 years of age. Tonsillectomy results in less frequent isolation of S. aureus strains. © 2016 APMIS. Published by John Wiley & Sons Ltd.

  8. Brain infection following experimental Staphylococcus aureus sepsis in pigs

    DEFF Research Database (Denmark)

    Astrup, Lærke Boye; Iburg, Tine Moesgaard; Nielsen, Ole Lerberg

    2010-01-01

    Introduction: Sepsis is a major problem in humans and both the incidence and mortality is increasing. Multiple microabcesses can be found in the brain of septic patients. Staphylococcus aureus is one of the most common causes of sepsis and brain abscesses. S. aureus is also a frequent cause...... pigs were kept as controls. The pigs were euthanized in groups of four at either 6, 12, 24 or 48 h post infection. The brain was collected from all the animals and examined histologically. Results: All the inoculated pigs developed sepsis and 7 out of 12 animals had microabscesses in the prosencephalon...

  9. Beta-Hemolysin Promotes Skin Colonization by Staphylococcus aureus

    OpenAIRE

    Katayama, Yuki; Baba, Tadashi; Sekine, Miwa; Fukuda, Minoru; Hiramatsu, Keiichi

    2013-01-01

    Colonization by Staphylococcus aureus is a characteristic feature of several inflammatory skin diseases and is often followed by epidermal damage and invasive infection. In this study, we investigated the mechanism of skin colonization by a virulent community-acquired methicillin-resistant S. aureus (CA-MRSA) strain, MW2, using a murine ear colonization model. MW2 does not produce a hemolytic toxin, beta-hemolysin (Hlb), due to integration of a prophage, ϕSa3mw, inside the toxin gene (hlb). H...

  10. Staphylococcus aureus still colonizes the untreated neonatal umbilicus.

    Science.gov (United States)

    Watkinson, M; Dyas, A

    1992-06-01

    Two different neonatal umbilical cord treatment regimens were studied prospectively. Although a greater proportion of cords had separated by the seventh day in those babies not treated with topical antiseptics (47% vs. 26%), there was a significant excess (53% vs. 30%) of umbilical colonization by Staphylococcus aureus compared to those neonates whose cords were treated with alcohol wipes and hexachlorophane powder. The main purpose of treating cords is to prevent significant S. aureus colonization, and therefore current proposals to stop antiseptic treatment of umbilical cords should be disregarded.

  11. Staphylococcus aureus CcpA affects biofilm formation

    OpenAIRE

    Seidl, K.; Goerke, C; Wolz, C; Mack, D; Berger-Bächi, B; Bischoff, M

    2008-01-01

    Biofilm formation in Staphylococcus aureus under in vitro growth conditions is generally promoted by high concentrations of sugar and/or salts. The addition of glucose to routinely used complex growth media triggered biofilm formation in S. aureus strain SA113. Deletion of ccpA, coding for the catabolite control protein A (CcpA), which regulates gene expression in response to the carbon source, abolished the capacity of SA113 to form a biofilm under static and flow conditions, while still all...

  12. 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.

  13. Epidemic Increase in Methicillin-resistant Staphylococcus aureus in Copenhagen

    DEFF Research Database (Denmark)

    Westh, Henrik; Boye, Kit; Bartels, Mette Damkjær

    2006-01-01

    INTRODUCTION: We have found an epidemic increase in methicillin-resistant Staphylococcus aureus (MRSA) in Copenhagen. The increase has a complex background and involves hospitals, nursing homes and persons nursed in their own home. MATERIAL AND METHODS: We found 33 MRSA patients in 2003 and 121...... in 2004. All isolates have been spa-typed and epidemiologic information collected. RESULTS: The number of MRSA cases has a doubling time of about six months. The epidemic has been caused by many different MRSA types and 31 staphylococcus protein A genotypes (spa types). MRSA has caused several hospital...

  14. Mastitis Bovina: Resistencia a antibióticos de cepas de Staphylococcus aureus asiladas de leche (Bovine Mastitis: Antimicrobial resistance of Staphylococcus aureus strains isolated from milk)

    OpenAIRE

    Pellegrino, MS; Frola, ID; Odierno, LM; Bogni, CI

    2011-01-01

    ResumenLa mastitis bovina es considerada la enfermedad infecciosa del ganado lechero de mayor impacto económico mundial, siendo Staphylococcus aureus el principal agente patógeno en muchos países.SummaryBovine mastitis is a frequent cause of economic loss in worldwide dairy herds, being Staphylococcus aureus the main etiological agent in many countries.

  15. Staphylococcus aureus biofilm formation at the physiologic glucose concentration depends on the S. aureus lineage

    NARCIS (Netherlands)

    Croes, Sander; Deurenberg, Ruud H; Boumans, Marie-Louise L; Beisser, Patrick S; Neef, Cees; Stobberingh, Ellen E

    2009-01-01

    BACKGROUND: Since bacteria embedded in biofilms are far more difficult to eradicate than planktonic infections, it would be useful to know whether certain Staphylococcus aureus lineages are especially involved in strong biofilm formation. For this reason, in vitro biofilm formation of 228 clinical

  16. Staphylococcus epidermidis Esp inhibits Staphylococcus aureus biofilm formation and nasal colonization.

    Science.gov (United States)

    Iwase, Tadayuki; Uehara, Yoshio; Shinji, Hitomi; Tajima, Akiko; Seo, Hiromi; Takada, Koji; Agata, Toshihiko; Mizunoe, Yoshimitsu

    2010-05-20

    Commensal bacteria are known to inhibit pathogen colonization; however, complex host-microbe and microbe-microbe interactions have made it difficult to gain a detailed understanding of the mechanisms involved in the inhibition of colonization. Here we show that the serine protease Esp secreted by a subset of Staphylococcus epidermidis, a commensal bacterium, inhibits biofilm formation and nasal colonization by Staphylococcus aureus, a human pathogen. Epidemiological studies have demonstrated that the presence of Esp-secreting S. epidermidis in the nasal cavities of human volunteers correlates with the absence of S. aureus. Purified Esp inhibits biofilm formation and destroys pre-existing S. aureus biofilms. Furthermore, Esp enhances the susceptibility of S. aureus in biofilms to immune system components. In vivo studies have shown that Esp-secreting S. epidermidis eliminates S. aureus nasal colonization. These findings indicate that Esp hinders S. aureus colonization in vivo through a novel mechanism of bacterial interference, which could lead to the development of novel therapeutics to prevent S. aureus colonization and infection.

  17. Comparison of eight methods to detect vancomycin resistance in enterococci

    NARCIS (Netherlands)

    H.P. Endtz (Hubert); N.P.W.C.J. van den Braak (Nicole); A.F. van Belkum (Alex); W.H.F. Goessens (Wil); D. Kreft; A.B. Stroebel; H.A. Verbrugh (Henri)

    1998-01-01

    textabstractA collection of genetically unrelated vancomycin-resistant enterococci (VRE) including 50 vanA, 15 vanB, 50 vanC1, and 30 vanC2 VRE were used to evaluate the accuracy of eight currently available susceptibility test methods (agar dilution, disk diffusion,

  18. Meningitis associated with Vancomycin resistant Enterococcus casseliflavus: First report

    OpenAIRE

    Duygu, Fazilet; Balcı, Pervin Özlem; Solmaz, Mehtap; Uçar, Nilay Sefa

    2015-01-01

    Enterococci are present in the gastrointestinal system as normal floral components. In the past two decades members of the genus Enterococcus have emerged as important nosocomial pathogens worldwide. Enterococci may cause a range of different disorders such as urinary tract, intraabdominal, and wound infections, as well as endocarditis, meningitis and bacteraemia. Nosocomial enterococcal meningitis is most commonly observed following ventriculoperitoneal shunt operations. Vancomycin resistant...

  19. Isolation of vancomycin resistant Enterococcus faecium from food

    DEFF Research Database (Denmark)

    Wegener, Henrik Caspar; Madsen, Mogens; Nielsen, Niels

    1997-01-01

    In a survey of vancomycin resistant Enterococcus faecium (VREF) in Danish meat products, VREF could be detected in 16% of 160 samples of broilers collected at slaughterhouses and in 15% of 26 samples of pork collected from the retail trade. VREF were isolated by enrichment for 24 h in nutrient...

  20. Infection caused by vancomycin-resistant Streptococcus sanguis II.

    Science.gov (United States)

    Shlaes, D M; Marino, J; Jacobs, M R

    1984-01-01

    A patient with bacteremia caused by vancomycin-resistant Streptococcus sanguis II is presented. This rare occurrence suggests that vancomycin may not be a completely reliable antibiotic in the treatment of infections due to viridans species of the genus Streptococcus. Gram-positive isolates from blood and otherwise sterile body fluids should be tested for susceptibility to vancomycin. PMID:6732222

  1. Threat of multidrug resistant Staphylococcus aureus in Western Nepal

    DEFF Research Database (Denmark)

    Bhatta, Dharm R.; Cavaco, Lina; Nath, Gopal

    2015-01-01

    ObjectiveTo determine the prevalence of methicillin resistant Staphylococcus aureus (MRSA) and antimicrobial susceptibility patterns of the isolates from Manipal Teaching Hospital, Pokhara, Nepal. MethodsThis study was conducted over a period of 11 months (September 2012–August 2013) at the Manipal...... using disc diffusion test by cefoxitin (30 μg) and oxacillin (1 μg) disc, further confirmation was done by detection of mecA gene using PCR. ResultsOut of 400 Staphylococcus aureus strains, 139 (34.75%) were found to be MRSA. Among the MRSA isolates, 74 (53.2%) were from inpatient departments, 58 (41...... Teaching Hospital, Pokhara, Nepal. A total of 400 isolates were collected from various clinical specimens including hospital units (operation theaters and intensive care units). Antibiotic susceptibility testing was performed by Kirby-Bauer disc diffusion method. Primary screening for MRSA was performed...

  2. Neutrophil evasion strategies by Streptococcus pneumoniae and Staphylococcus aureus.

    Science.gov (United States)

    Lewis, Megan L; Surewaard, Bas G J

    2017-12-05

    Humans are well equipped to defend themselves against bacteria. The innate immune system employs diverse mechanisms to recognize, control and initiate a response that can destroy millions of different microbes. Microbes that evade the sophisticated innate immune system are able to escape detection and could become pathogens. The pathogens Streptococcus pneumoniae and Staphylococcus aureus are particularly successful due to the development of a wide variety of virulence strategies for bacterial pathogenesis and they invest significant efforts towards mechanisms that allow for neutrophil evasion. Neutrophils are a primary cellular defense and can rapidly kill invading microbes, which is an indispensable function for maintaining host health. This review compares the key features of Streptococcus pneumoniae and Staphylococcus aureus in epidemiology, with a specific focus on virulence mechanisms utilized to evade neutrophils in bacterial pathogenesis. It is important to understand the complex interactions between pathogenic bacteria and neutrophils so that we can disrupt the ability of pathogens to cause disease.

  3. Staphylococcus aureus Central Nervous System Infections in Children.

    Science.gov (United States)

    Vallejo, Jesus G; Cain, Alexandra N; Mason, Edward O; Kaplan, Sheldon L; Hultén, Kristina G

    2017-10-01

    Central nervous system (CNS) infections caused by Staphylococcus aureus are uncommon in pediatric patients. We review the epidemiology, clinical features and treatment in 68 patients with a S. aureus CNS infection evaluated at Texas Children's Hospital. Cases of CNS infection in children with positive cerebrospinal fluid cultures or spinal epidural abscess (SEA) for S. aureus at Texas Children's Hospital from 2001 to 2013 were reviewed. Seventy cases of S. aureus CNS infection occurred in 68 patients. Forty-nine cases (70%) were secondary to a CNS device, 5 (7.1%) were postoperative meningitis, 9 (12.8%) were hematogenous meningitis and 7 (10%) were SEAs. Forty-seven (67.2%) were caused by methicillin-sensitive S. aureus (MSSA) and 23 (32.8%) by methicillin-resistant S. aureus (MRSA). Community-acquired infections were more often caused by MRSA that was clone USA300/pvl. Most patients were treated with nafcillin (MSSA) or vancomycin (MRSA) with or without rifampin. Among patients with MRSA infection, 50% had a serum vancomycin trough obtained with the median level being 10.6 μg/mL (range: 5.4-15.7 μg/mL). Only 1 death was associated with S. aureus infection. The epidemiology of invasive of S. aureus infections continues to evolve with MSSA accounting for most of the infections in this series. The majority of cases were associated with neurosurgical procedures; however, hematogenous S. aureus meningitis and SEA occurred as community-acquired infections in patients without predisposing factors. Patients with MRSA CNS infections had a favorable response to vancomycin, but the beneficial effect of combination therapy or targeting vancomycin trough concentrations of 15-20 μg/mL remains unclear.

  4. Methicillin-resistant Staphylococcus aureus infection in the obstetric setting.

    Science.gov (United States)

    Kriebs, Jan M

    2008-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is an increasingly prevalent pathogen, both in the community and in hospitalized patients. The virulence of MRSA, coupled with its resistance to many frequently prescribed antibiotics, requires increased vigilance in the assessment and diagnosis of skin and soft tissue infections. This article reviews the epidemiology of MRSA and focuses on treatment of MRSA when it is diagnosed during pregnancy.

  5. A Rare Presentation of Community Acquired Methicillin Resistant Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    J. Docekal

    2013-01-01

    Full Text Available Prostatic abscess is a rarely described condition and is commonly caused by gram-negative organisms such as enterobacteria. However, as the prevalence of methicillin resistant Staphylococcus aureus (MRSA increases in the community, unusual infections due to this organism have been recently published. In this report, we describe a patient with diabetes mellitus type 2, who presents with diabetic ketoacidosis—later found to be due to a prostatic abscess from which MRSA was cultured.

  6. Assessment of Ibicella lutea for antibacterial agent front Staphylococcus aureus

    OpenAIRE

    Lisiane Martins Volcão; Tatiane Silveira Coelho; Alváro Vàsquez; Maria Pia Cerdeiras; Pedro Eduardo Almeida da Silva; Flávio Manoel Rodrigues da Silva Júnior; Daniela Fernandes Ramos

    2016-01-01

    Justificative and Objectives: the study aimed the assessment of the antibacterial activity of crude extracts and fractions of Ibicella lutea, front Staphylococcus aureus, thecombination of these compounds and cytotoxic activity. Methods: was used for antibacterial activity the Microdilution Test Broth, and performed the Checkerboard Test. The extracts showed antibacterial activity were submitted to the citotoxicity test, with macrophages cell and determination of the Selectivity Index (SI). R...

  7. Fatal pneumoni med Panton-Valentine-leukocidinproducerende Staphylococcus aureus

    DEFF Research Database (Denmark)

    Rabøl, Peter Hedelund; Dessau, Ram Benny; Warnecke, Mads

    2010-01-01

    We describe a case of fatal pneumonia in a previously healthy 14-year-old boy. The patient was severely affected at the time of admission with high fever, tachypnea, tachycardia and peripheral cyanosis. The condition worsened despite treatment with antibiotics as well as respiratory and pressure ...... support. Acidosis and critical leucopenia supervened and the patient died just short of 24 hours after admission. Subsequent bacterial cultivation showed Panton-Valentine Leucocidin-producing Staphylococcus aureus....

  8. Involvement of multiple genetic loci in Staphylococcus aureus teicoplanin resistance

    OpenAIRE

    Bischoff, Markus; Roos, Martin; Putnik, Jasmina; Wada, Akihito; Glanzmann, Philipp; Giachino, Philipp; Vaudaux, Pierre; Berger-Bächi, B.

    2017-01-01

    Teicoplanin resistance was transformed from a teicoplanin-resistant Staphylococcus aureus into the susceptible strain BB255 to give strain BB938. The cell wall composition, amidation of the iD-glutamate, and peptide crosslinking were identical in BB938 as in BB255 except for a 60% increased length of the glycan chain. Transductional crosses revealed that at least two distinct loci contributed in a cumulative fashion to teicoplanin resistance. One of these loci correlated with a mutation inact...

  9. Antimicrobial Photodynamic Therapy for Methicillin-Resistant Staphylococcus aureus Infection

    OpenAIRE

    Fu, Xiu-jun; Fang, Yong; Yao, Min

    2013-01-01

    Nowadays methicillin-resistant Staphylococcus aureus (MRSA) is one of the most common multidrug resistant bacteria both in hospitals and in the community. In the last two decades, there has been growing concern about the increasing resistance to MRSA of the most potent antibiotic glycopeptides. MRSA infection poses a serious problem for physicians and their patients. Photosensitizer-mediated antimicrobial photodynamic therapy (PDT) appears to be a promising and innovative approach for treatin...

  10. Prevalence of icaA and icaD genes in Staphylococcus aureus and Staphylococcus epidermidis strains isolated from patients and hospital staff

    National Research Council Canada - National Science Library

    Satorres, Sara Elena; Alcaráz, Lucia Esther

    2007-01-01

    .... Staphylococcus aureus and Staphylococcus epidermidis have been identified as a major cause of nosocomial infections, especially in patients with predisposing factors such as indwelling or implanted foreign bodies...

  11. Staphylococcus aureus phage types and their correlation to antibiotic resistance

    Directory of Open Access Journals (Sweden)

    Mehndiratta P

    2010-10-01

    Full Text Available Context: Staphylococcus aureus is one of the most devastating human pathogen. The organism has a differential ability to spread and cause outbreak of infections. Characterization of these strains is important to control the spread of infection in the hospitals as well as in the community. Aim: To identify the currently existing phage groups of Staphylococcus aureus, their prevalence and resistance to antibiotics. Materials and Methods: Study was undertaken on 252 Staphylococcus aureus strains isolated from clinical samples. Strains were phage typed and their resistance to antibiotics was determined following standard microbiological procedures. Statistical Analysis: Chi square test was used to compare the antibiotic susceptibility between methicillin resistant Staph. aureus (MRSA and methicillin sensitive S. aureus (MSSA strains. Results: Prevalence of MRSA and MSSA strains was found to be 29.36% and 70.65% respectively. Of these 17.56% of MRSA and 40.44% of MSSA strains were community acquired. All the MSSA strains belonging to phage type 81 from the community were sensitive to all the antibiotics tested including clindamycin and were resistant to penicillin. Forty five percent strains of phage group III and 39% of non-typable MRSA strains from the hospital were resistant to multiple antibiotics. Conclusion: The study revealed that predominant phage group amongst MRSA strains was phage group III and amongst MSSA from the community was phage group NA (phage type 81. MSSA strains isolated from the community differed significantly from hospital strains in their phage type and antibiotic susceptibility. A good correlation was observed between community acquired strains of phage type 81 and sensitivity to gentamycin and clindamycin.

  12. Diversity of Staphylococcus aureus Isolates in European Wildlife

    Science.gov (United States)

    Monecke, Stefan; Gavier-Widén, Dolores; Hotzel, Helmut; Peters, Martin; Guenther, Sebastian; Lazaris, Alexandros; Loncaric, Igor; Müller, Elke; Reissig, Annett; Ruppelt-Lorz, Antje; Shore, Anna C.; Walter, Birgit; Coleman, David C.; Ehricht, Ralf

    2016-01-01

    Staphylococcus aureus is a well-known colonizer and cause of infection among animals and it has been described from numerous domestic and wild animal species. The aim of the present study was to investigate the molecular epidemiology of S. aureus in a convenience sample of European wildlife and to review what previously has been observed in the subject field. 124 S. aureus isolates were collected from wildlife in Germany, Austria and Sweden; they were characterized by DNA microarray hybridization and, for isolates with novel hybridization patterns, by multilocus sequence typing (MLST). The isolates were assigned to 29 clonal complexes and singleton sequence types (CC1, CC5, CC6, CC7, CC8, CC9, CC12, CC15, CC22, CC25, CC30, CC49, CC59, CC88, CC97, CC130, CC133, CC398, ST425, CC599, CC692, CC707, ST890, CC1956, ST2425, CC2671, ST2691, CC2767 and ST2963), some of which (ST2425, ST2691, ST2963) were not described previously. Resistance rates in wildlife strains were rather low and mecA-MRSA isolates were rare (n = 6). mecC-MRSA (n = 8) were identified from a fox, a fallow deer, hares and hedgehogs. The common cattle-associated lineages CC479 and CC705 were not detected in wildlife in the present study while, in contrast, a third common cattle lineage, CC97, was found to be common among cervids. No Staphylococcus argenteus or Staphylococcus schweitzeri-like isolates were found. Systematic studies are required to monitor the possible transmission of human- and livestock-associated S. aureus/MRSA to wildlife and vice versa as well as the possible transmission, by unprotected contact to animals. The prevalence of S. aureus/MRSA in wildlife as well as its population structures in different wildlife host species warrants further investigation. PMID:27992523

  13. [Carriage of Staphylococcus aureus. A severity factor of erysipelas?].

    Science.gov (United States)

    Bernard, P; Risse, L; Mounier, M; Bonnetblanc, J M

    1996-01-01

    Occasional superinfection or co-infection with Staphylococcus aureus led us to search for S. aureus carriage prospectively in patients with non-necrotizing bacterial dermophypodermitis, in particular erysipelas. This prospective study included immunocompetent patients with bacterial dermophypodermitis without signs of toxicity or local manifestations suggesting necrotizing fasciitis. Bacteriology tests included: 1) direct immunofluorescence for streptococcus (groups A, C, G) on skin biopsies taken on day 0, 2) samples from the nasal orifices, the intergluteal fold, and potential skin portals for bacteriology culture, and 3) assay of antistreptolysine O and antistreptodornase B on day 0 and 15. The study group included 42 patients (23 females, 19 males, mean age 64 +/- 3.5 yr). In 39 cases (93%) bacterial dermohypodermitis was located on the lower limb with a potential skin portal in 36 cases (86%). Sample culture, direct immunofluorescence or serology findings demonstrated presence of streptococci in 33 cases (79%). Nasal, intergluteal or potential portal were identified in 19 patients (45%) including 16 with demonstrated presence of streptococci. The rate of cure after oral pristinamycin did not vary significantly between carriers (79%) an non-carriers (91%) of Staphylococcus aureus. Drainage of a localized abscess was successful in 5 of 6 patients after initial failure of antibiotic treatment; 4 of them were carriers of S. aureus. This prospective study demonstrated that cutaneous-mucosal carriage of Staphylococcus aureus is frequent in patients with non-necrotizing dermohypodermitis. This carriage is not a factor of over-morbidity as shown in this group of infections largely dominated by erysipelas.

  14. Diversity of Staphylococcus aureus Isolates in European Wildlife.

    Directory of Open Access Journals (Sweden)

    Stefan Monecke

    Full Text Available Staphylococcus aureus is a well-known colonizer and cause of infection among animals and it has been described from numerous domestic and wild animal species. The aim of the present study was to investigate the molecular epidemiology of S. aureus in a convenience sample of European wildlife and to review what previously has been observed in the subject field. 124 S. aureus isolates were collected from wildlife in Germany, Austria and Sweden; they were characterized by DNA microarray hybridization and, for isolates with novel hybridization patterns, by multilocus sequence typing (MLST. The isolates were assigned to 29 clonal complexes and singleton sequence types (CC1, CC5, CC6, CC7, CC8, CC9, CC12, CC15, CC22, CC25, CC30, CC49, CC59, CC88, CC97, CC130, CC133, CC398, ST425, CC599, CC692, CC707, ST890, CC1956, ST2425, CC2671, ST2691, CC2767 and ST2963, some of which (ST2425, ST2691, ST2963 were not described previously. Resistance rates in wildlife strains were rather low and mecA-MRSA isolates were rare (n = 6. mecC-MRSA (n = 8 were identified from a fox, a fallow deer, hares and hedgehogs. The common cattle-associated lineages CC479 and CC705 were not detected in wildlife in the present study while, in contrast, a third common cattle lineage, CC97, was found to be common among cervids. No Staphylococcus argenteus or Staphylococcus schweitzeri-like isolates were found. Systematic studies are required to monitor the possible transmission of human- and livestock-associated S. aureus/MRSA to wildlife and vice versa as well as the possible transmission, by unprotected contact to animals. The prevalence of S. aureus/MRSA in wildlife as well as its population structures in different wildlife host species warrants further investigation.

  15. Diversity of Staphylococcus aureus Isolates in European Wildlife.

    Science.gov (United States)

    Monecke, Stefan; Gavier-Widén, Dolores; Hotzel, Helmut; Peters, Martin; Guenther, Sebastian; Lazaris, Alexandros; Loncaric, Igor; Müller, Elke; Reissig, Annett; Ruppelt-Lorz, Antje; Shore, Anna C; Walter, Birgit; Coleman, David C; Ehricht, Ralf

    2016-01-01

    Staphylococcus aureus is a well-known colonizer and cause of infection among animals and it has been described from numerous domestic and wild animal species. The aim of the present study was to investigate the molecular epidemiology of S. aureus in a convenience sample of European wildlife and to review what previously has been observed in the subject field. 124 S. aureus isolates were collected from wildlife in Germany, Austria and Sweden; they were characterized by DNA microarray hybridization and, for isolates with novel hybridization patterns, by multilocus sequence typing (MLST). The isolates were assigned to 29 clonal complexes and singleton sequence types (CC1, CC5, CC6, CC7, CC8, CC9, CC12, CC15, CC22, CC25, CC30, CC49, CC59, CC88, CC97, CC130, CC133, CC398, ST425, CC599, CC692, CC707, ST890, CC1956, ST2425, CC2671, ST2691, CC2767 and ST2963), some of which (ST2425, ST2691, ST2963) were not described previously. Resistance rates in wildlife strains were rather low and mecA-MRSA isolates were rare (n = 6). mecC-MRSA (n = 8) were identified from a fox, a fallow deer, hares and hedgehogs. The common cattle-associated lineages CC479 and CC705 were not detected in wildlife in the present study while, in contrast, a third common cattle lineage, CC97, was found to be common among cervids. No Staphylococcus argenteus or Staphylococcus schweitzeri-like isolates were found. Systematic studies are required to monitor the possible transmission of human- and livestock-associated S. aureus/MRSA to wildlife and vice versa as well as the possible transmission, by unprotected contact to animals. The prevalence of S. aureus/MRSA in wildlife as well as its population structures in different wildlife host species warrants further investigation.

  16. Nickel allergy and relationship with Staphylococcus aureus in atopic dermatitis.

    Science.gov (United States)

    Bogdali, Anna M; Anna, Bogdali M; Grazyna, Antoszczyk; Wojciech, Dyga; Aleksander, Obtulowicz; Anna, Bialecka; Andrzej, Kasprowicz; Zofia, Magnowska; Krystyna, Obtulowicz

    2016-01-01

    The increase of nickel air pollution is supposed to frequent side effects of nickel action related to virulence potential of Staphylococcus aureus in patients with nickel allergy in atopic dermatitis. The goal was to investigate the relationship between nickel allergy and infection by S. aureus in atopic dermatitis. Nickel allergy was confirmed in atopic patients and excluded in healthy volunteers using patch testing. Infection by S. aureus was tested in atopic patients and healthy volunteers by use of API Staph system. The specific IgE for staphylococcal enterotoxin A and B were measured. Secretion of IFN-g, IL-2, IL-13 by PBMC under nickel sulfate and the enterotoxins A and B stimulations were studied with ELISpot. We found the increased number of infections by S. aureus in atopic patients with nickel allergy in comparison to atopic patients and healthy volunteers without nickel allergy. The elevated secretion of IL-2 under nickel sulfate stimulation in vitro was exclusively found in atopic patients with nickel allergy infected by S. aureus. Our data suggest that nickel allergy and infection by S. aureus are linked in atopic dermatitis. Copyright © 2015 Elsevier GmbH. All rights reserved.

  17. "Gesundheit!" sneezing, common colds, allergies, and Staphylococcus aureus dispersion.

    Science.gov (United States)

    Bischoff, Werner E; Wallis, Michelle L; Tucker, Brian K; Reboussin, Beth A; Pfaller, Michael A; Hayden, Frederick G; Sherertz, Robert J

    2006-10-15

    Staphylococcus aureus is among the most important pathogens in today's hospital setting. The effects of sneezing on the airborne dispersal of S. aureus and other bacteria were assessed in 11 healthy nasal S. aureus carriers with experimentally induced rhinovirus colds. Airborne dispersal was studied by volumetric air sampling in 2 chamber sessions with and without histamine-induced sneezing. After 2 days of preexposure measurements, volunteers were inoculated with a rhinovirus and monitored for 14 days. Daily quantitative nasal- and skin-culture samples for bacteria and nasal-culture samples for rhinovirus were obtained, cold symptoms were assessed, and volunteer activities were recorded during sessions. All participants developed a cold. Sneezing caused a 4.7-fold increase in the airborne dispersal of S. aureus, a 1.4-fold increase in coagulase-negative staphylococci (CoNS), and a 3.9-fold increase in other bacteria (P Rhinovirus exposure did not change the frequency of sneezing or airborne dispersal. Having respiratory allergies increased the spread of S. aureus by 3.8-fold during sneezing sessions (P effect of dispersing S. aureus.

  18. Resistance to Antimicrobials Mediated by Efflux Pumps in Staphylococcus aureus

    Science.gov (United States)

    Costa, Sofia S.; Junqueira, Elisabete; Palma, Cláudia; Viveiros, Miguel; Melo-Cristino, José; Amaral, Leonard; Couto, Isabel

    2013-01-01

    Resistance mediated by efflux has been recognized in Staphylococcus aureus in the last few decades, although its clinical relevance has only been recognized recently. The existence of only a few studies on the individual and overall contribution of efflux to resistance phenotypes associated with the need of well-established methods to assess efflux activity in clinical isolates contributes greatly to the lack of solid knowledge of this mechanism in S. aureus. This study aims to provide information on approaches useful to the assessment and characterization of efflux activity, as well as contributing to our understanding of the role of efflux to phenotypes of antibiotic resistance and biocide tolerance in S. aureus clinical isolates. The results described show that efflux is an important contributor to fluoroquinolone resistance in S. aureus and suggest it as a major mechanism in the early stages of resistance development. We also show that efflux plays an important role on the reduced susceptibility to biocides in S. aureus, strengthening the importance of this long neglected resistance mechanism to the persistence and proliferation of antibiotic/biocide-resistant S. aureus in the hospital environment. PMID:27029294

  19. Antibiotic Combinations with Daptomycin for Treatment of Staphylococcus aureus Infections

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    Kristina Nadrah

    2011-01-01

    Full Text Available Daptomycin is a lipopeptide antibiotic with a unique mechanism of action on Gram-positive bacteria. It is approved for treatment of skin and soft-tissue infections with Gram-positive bacteria, bacteraemia and right-sided infective endocarditis caused by Staphylococcus aureus. Diminishing susceptibility of S. aureus to daptomycin during treatment of complicated infections and clinical failure have been described. Combinations of daptomycin with other antibiotics including gentamicin, rifampin, beta-lactams, trimethoprim/sulfamethoxazole (TMP-SMX, or clarithromycin present a new approach for therapy. In vitro and animal studies have shown that such combinations may, in some cases, be superior to daptomycin monotherapy. In this paper we focus on the antibiotic combinations for complicated S. aureus infections.

  20. Staphylococcus aureus biofilms: recent developments in biofilm dispersal.

    Science.gov (United States)

    Lister, Jessica L; Horswill, Alexander R

    2014-01-01

    Staphylococcus aureus is a major cause of nosocomial and community-acquired infections and represents a significant burden on the healthcare system. S. aureus attachment to medical implants and host tissue, and the establishment of a mature biofilm, play an important role in the persistence of chronic infections. The formation of a biofilm, and encasement of cells in a polymer-based matrix, decreases the susceptibility to antimicrobials and immune defenses, making these infections difficult to eradicate. During infection, dispersal of cells from the biofilm can result in spread to secondary sites and worsening of the infection. In this review, we discuss the current understanding of the pathways behind biofilm dispersal in S. aureus, with a focus on enzymatic and newly described broad-spectrum dispersal mechanisms. Additionally, we explore potential applications of dispersal in the treatment of biofilm-mediated infections.

  1. Biochemical Characterization of Lysine Auxotrophs of Staphylococcus aureus1

    Science.gov (United States)

    Barnes, Isabel J.; Bondi, Amedeo; Moat, Albert G.

    1969-01-01

    Lysine biosynthesis in Staphylococcus aureus has been studied by use of a series of lysine auxotrophs. The strains were isolated after chemical mutagenesis. The majority of these mutant strains were classified according to the enzymatic step found to be deficient. Specific enzyme assays as well as nutritional tests were used to group the organisms. The enzymes included were dihydrodipicolinate synthetase, dihydrodipicolinate reductase, diaminopimelate epimerase, and diaminopimelate decarboxylase. The accumulation of diaminopimelate in certain mutants and the demonstration of dihydrodipicolinate synthetase and reductase provide the first detailed evidence that S. aureus utilizes the diaminopimelate pathway for lysine biosynthesis. A cell-free system was used to study the regulation of these enzymes with the exception of diaminopimelate epimerase. Lysine repressed all of the enzymes tested. The repression appeared to be coordinate in nature. The data presented provide suggestive evidence that the lysine biosynthetic region in S. aureus constitutes an operon. PMID:5802602

  2. Population structure of Staphylococcus aureus from Trinidad & Tobago.

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    Stefan Monecke

    Full Text Available It has been shown previously that high rates of methicillin- and mupirocin-resistant Staphylococcus aureus exist in the Caribbean islands of Trinidad and Tobago, as well as a high prevalence of Panton-Valentine leukocidin-positive S. aureus. Beyond these studies, limited typing data have been published. In order to obtain insight into the population structure not only of MRSA but also of methicillin-susceptible S. aureus, 294 clinical isolates collected in 2012/2013 were typed by microarray hybridisation. A total of 15.31% of the tested isolates were MRSA and 50.00% were PVL-positive. The most common MSSA strains were PVL-positive CC8-MSSA (20.41% of all isolates tested, PVL-positive CC152-MSSA (9.52% and PVL-positive CC30-MSSA (8.84% while the most common MRSA were ST239-MRSA-III&SCCmer (9.18% and ST8-MRSA-IV, "USA300" (5.78%. 2.38% of characterised isolates belonged to distinct strains likely to be related to "Staphylococcus argenteus" lineages. The population structure of S. aureus isolates suggests an importation of strains from Africa, endemicity of PVL-positive MSSA (mainly CC8 and of ST239-MRSA-III, and a recent emergence of the PVL-positive CC8-MRSA-IV strain "USA300".

  3. Population structure of Staphylococcus aureus from Trinidad & Tobago.

    Science.gov (United States)

    Monecke, Stefan; Stieber, Bettina; Roberts, Rashida; Akpaka, Patrick Eberechi; Slickers, Peter; Ehricht, Ralf

    2014-01-01

    It has been shown previously that high rates of methicillin- and mupirocin-resistant Staphylococcus aureus exist in the Caribbean islands of Trinidad and Tobago, as well as a high prevalence of Panton-Valentine leukocidin-positive S. aureus. Beyond these studies, limited typing data have been published. In order to obtain insight into the population structure not only of MRSA but also of methicillin-susceptible S. aureus, 294 clinical isolates collected in 2012/2013 were typed by microarray hybridisation. A total of 15.31% of the tested isolates were MRSA and 50.00% were PVL-positive. The most common MSSA strains were PVL-positive CC8-MSSA (20.41% of all isolates tested), PVL-positive CC152-MSSA (9.52%) and PVL-positive CC30-MSSA (8.84%) while the most common MRSA were ST239-MRSA-III&SCCmer (9.18%) and ST8-MRSA-IV, "USA300" (5.78%). 2.38% of characterised isolates belonged to distinct strains likely to be related to "Staphylococcus argenteus" lineages. The population structure of S. aureus isolates suggests an importation of strains from Africa, endemicity of PVL-positive MSSA (mainly CC8) and of ST239-MRSA-III, and a recent emergence of the PVL-positive CC8-MRSA-IV strain "USA300".

  4. PREVALENCIA DE Staphylococcus epidermidis Y Staphylococcus aureus EN PACIENTES CON CONJUNTIVITIS

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    P. Hernández-Rodríguez

    2005-12-01

    Full Text Available Con el fin de establecer la prevalencia de Staphylococcus epidermidis y Staphylococcus aureus en pacientes con conjuntivitis, se evaluaron clínica y bacteriológicamente 131 pacientes con diagnóstico clínico presuntivo de conjuntivitis. A cada participante se le tomó muestra de secreción ocular, para la coloración de Gram y cultivo; además, se probó la susceptibilidad de los aislamientos frente a Oxacilina (Ox, Gentamicina (GM, Vancomicina (Va, Trimetoprim Sulfamethoxazole (SXT, Tetraciclina (Te, Cefalothin (CF, Ceftriaxone (CRO y Ciprofloxacina (CIP. El 53% de los cultivos bacteriológicos fueron positivos, donde el 87% de los aislamientos correspondieron a Gram positivos, siendo los más frecuentes Staphylococcus epidermidis (43%, Staphylococcus aureus (30%, Streptococcus sp. (15%, Enterococcus (7%, Corynebacterium sp. 5%. Se observó multirresistencia frente a 3 ó más antibióticos en S. epidermidis (44% y S.aureus (42%. La alta frecuencia de estos microorganismos y la multirresistencia encontrada en este estudio, determinan la importancia que tienen, como posibles patógenos oculares, y la necesidad de implementar las pruebas de susceptibilidad bacteriana en el ámbito oftalmológico. Este es el primer estudio publicado en Colombia sobre la prevalencia de Staphylococcus epidermidis y Staphylococcus aureus en pacientes con conjuntivitis, el cual seguramente originará la iniciación de posteriores investigaciones, encaminadas a determinar el verdadero papel de estos microorganismos, en el proceso infeccioso ocular.

  5. Effect of lactic acid bacteria on growth of Staphylococcus aureus.

    Science.gov (United States)

    Kao, C T; Frazier, W C

    1966-03-01

    Cultures of lactic acid bacteria, mostly from foods, were tested for their effect on the growth of Staphylococcus aureus in Trypticase Soy Broth (BBL). Some of the effectors, e.g., Streptococcus faecalis, S. faecium, Lactobacillus lactis, L. brevis, and Leuconostoc mesenteroides, stimulated growth of S. aureus during early hours of growth, especially at higher temperatures of incubation, but most cultures were inhibitory, and some (S. faecium and L. mesenteroides) were even killing by the time of attainment of the maximal phase of growth of the Staphylococcus. Low-temperature meat lactobacilli and Leuconostoc dextranicum inhibited S. aureus at 10, 15, 20, and 25 C throughout its growth. Streptococcus faecalis var. liquefaciens inhibited at these temperatures and at 30 and 37 C, as well. When the ratio of effectors to staphylococci in the inoculum was 100:1, the three enterococci, the meat Lactobacillus, and L. dextranicum prevented the attainment of 5 x 10(6) staphylococci per milliliter at 15 C, and all but the meat Lactobacillus did so at 22 C. A ratio of 1:1 accomplished similar results at 15 C, except that S. aureus was only delayed for 12 hr by S. faecalis. A ratio of 1:100 usually was ineffective. In general, the more effector bacteria there were in the inoculum, the greater was the overall inhibition (or stimulation) of S. aureus. Inhibition was most effective at 10 or 15 C, less so at 20 or 25 C, and least at 30 or 37 C, whereas stimulation during early growth was greater at the higher temperatures. Results with different strains of the effectors and with two strains of S. aureus were similar, for the most part.

  6. Bovine Staphylococcus aureus: Subtyping, evolution, and zoonotic transfer.

    Science.gov (United States)

    Boss, R; Cosandey, A; Luini, M; Artursson, K; Bardiau, M; Breitenwieser, F; Hehenberger, E; Lam, Th; Mansfeld, M; Michel, A; Mösslacher, G; Naskova, J; Nelson, S; Podpečan, O; Raemy, A; Ryan, E; Salat, O; Zangerl, P; Steiner, A; Graber, H U

    2016-01-01

    Staphylococcus aureus is globally one of the most important pathogens causing contagious mastitis in cattle. Previous studies using ribosomal spacer (RS)-PCR, however, demonstrated in Swiss cows that Staph. aureus isolated from bovine intramammary infections are genetically heterogeneous, with Staph. aureus genotype B (GTB) and GTC being the most prominent genotypes. Furthermore, Staph. aureus GTB was found to be contagious, whereas Staph. aureus GTC and all the remaining genotypes were involved in individual cow disease. In addition to RS-PCR, other methods for subtyping Staph. aureus are known, including spa typing and multilocus sequence typing (MLST). They are based on sequencing the spa and various housekeeping genes, respectively. The aim of the present study was to compare the 3 analytic methods using 456 strains of Staph. aureus isolated from milk of bovine intramammary infections and bulk tanks obtained from 12 European countries. Furthermore, the phylogeny of animal Staph. aureus was inferred and the zoonotic transfer of Staph. aureus between cattle and humans was studied. The analyzed strains could be grouped into 6 genotypic clusters, with CLB, CLC, and CLR being the most prominent ones. Comparing the 3 subtyping methods, RS-PCR showed the highest resolution, followed by spa typing and MLST. We found associations among the methods but in many cases they were unsatisfactory except for CLB and CLC. Cluster CLB was positive for clonal complex (CC)8 in 99% of the cases and typically positive for t2953; it is the cattle-adapted form of CC8. Cluster CLC was always positive for tbl 2645 and typically positive for CC705. For CLR and the remaining subtypes, links among the 3 methods were generally poor. Bovine Staph. aureus is highly clonal and a few clones predominate. Animal Staph. aureus always evolve from human strains, such that every human strain may be the ancestor of a novel animal-adapted strain. The zoonotic transfer of IMI- and milk-associated strains

  7. Membrane damage elicits an immunomodulatory program in Staphylococcus aureus.

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    Ahmed S Attia

    2010-03-01

    Full Text Available The Staphylococcus aureus HrtAB system is a hemin-regulated ABC transporter composed of an ATPase (HrtA and a permease (HrtB that protect S. aureus against hemin toxicity. S. aureus strains lacking hrtA exhibit liver-specific hyper-virulence and upon hemin exposure over-express and secrete immunomodulatory factors that interfere with neutrophil recruitment to the site of infection. It has been proposed that heme accumulation in strains lacking hrtAB is the signal which triggers S. aureus to elaborate this anti-neutrophil response. However, we report here that S. aureus strains expressing catalytically inactive HrtA do not elaborate the same secreted protein profile. This result indicates that the physical absence of HrtA is responsible for the increased expression of immunomodulatory factors, whereas deficiencies in the ATPase activity of HrtA do not contribute to this process. Furthermore, HrtB expression in strains lacking hrtA decreases membrane integrity consistent with dysregulated permease function. Based on these findings, we propose a model whereby hemin-mediated over-expression of HrtB in the absence of HrtA damages the staphylococcal membrane through pore formation. In turn, S. aureus senses this membrane damage, triggering the increased expression of immunomodulatory factors. In support of this model, wildtype S. aureus treated with anti-staphylococcal channel-forming peptides produce a secreted protein profile that mimics the effect of treating DeltahrtA with hemin. These results suggest that S. aureus senses membrane damage and elaborates a gene expression program that protects the organism from the innate immune response of the host.

  8. Staphylococcus aureus nasal carriage in hemodialysis centers of Fez, Morocco.

    Science.gov (United States)

    Diawara, Idrissa; Bekhti, Khadija; Elhabchi, Driss; Saile, Rachid; Elmdaghri, Naima; Timinouni, Mohammed; Elazhari, Mohamed

    2014-06-01

    Staphylococcus aureus (S. aureus) nasal carriage may be responsible for some serious infections in hemodialyzed patients. The main target of this study was to estimate the prevalence of S. aureus nasal carriage in hemodialysis outpatients and medical staff in hemodialysis centers specifically in Fez region. The second target is to identify the risks of colonization, resistance pattern of isolates and their virulence toxin genes. Nasal swab specimens were obtained from 143 hemodialyzed outpatients and 32 medical staff from January to June 2012. Each participant completed a short questionnaire. Nasal carriage of S. aureus was demographically related (age, gender, hemodialysis duration), comorbidity (diabetes, malignancy) and exposure to health care (dialysis staff, hospitalization). PCR (Polymerase Chain Reaction) were used on all the isolates in the research of twelve staphylococcal enterotoxins genes. Also the PCR was used to investigate on the three factors epidermal cell differentiation inhibitors; three exfoliatin toxins; two leukotoxins; the toxic shock syndrome toxin-1 and the hemolysin beta genes. Nasal screening revealed 38.16%, 50% and 18.75% S. aureus carries in chronic, acute hemodialysis patients and medical staff, respectively. Only young participants were likely to be S. aureus carries (p = 0.002). But there were no gender differences between the isolate carriers and non-carriers or some comorbidity factors such as viral hepatitis B and C, HIV (Human Immunodeficiency Virus) infections, diabetes, chronic smoking, recent hospitalization or antibiotic therapy. Out of all isolates, only one (1.61%) was methicillin-resistant and Twenty-one (33.87%) had at least two virulence toxin genes. Knowledge and monitoring of antibiotic resistance profile and virulence of S. aureus carriage are essential in the treatment of infections generated by this pathogen, as well as in the control of clonal dissemination and prevent the spread of S. aureus resistance.

  9. Staphylococcus aureus in the community: colonization versus infection.

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    Maureen Miller

    Full Text Available BACKGROUND: Antibiotic-resistant Staphylococcus aureus infections have increased dramatically in the community, yet S. aureus nasal colonization has remained stable. The objectives of this study were to determine if S. aureus colonization is a useful proxy measure to study disease transmission and infection in community settings, and to identify potential community reservoirs. METHODOLOGY/PRINCIPAL FINDINGS: Randomly selected households in Northern Manhattan, completed a structured social network questionnaire and provided nasal swabs that were typed by pulsed field gel electrophoresis to identify S. aureus colonizing strains. The main outcome measures were: 1 colonization with S. aureus; and 2 recent serious skin infection. Risk factor analyses were conducted at both the individual and the household levels; logistic regression models identified independent risks for household colonization and infection. RESULTS: 321 surveyed households contained 914 members. The S. aureus prevalence was 25% and MRSA was 0.4%. More than 40% of households were colonized. Recent antibiotic use was the only significant correlate for household colonization (p = .002. Seventy-eight (24% households reported serious skin infection. In contrast with colonization, five of the six risk factors that increased the risk of skin infection in the household at the univariate level remained independently significant in multivariable analysis: international travel, sports participation, surgery, antibiotic use and towel sharing. S. aureus colonization was not significantly associated with serious skin infection in any analysis. Among multiperson households with more than one person colonized, 50% carried the same strain. CONCLUSIONS/SIGNIFICANCE: The lack of association between S. aureus nasal colonization and serious skin infection underscores the need to explore alternative venues or body sites that may be crucial to transmission. Moreover, the magnitude of colonization and

  10. Mupirocin prophylaxis against nosocomial Staphylococcus aureus infections in nonsurgical patients: a randomized study

    NARCIS (Netherlands)

    M.C. Vos (Margreet); A. Ott (Alewijn); A. Voss (Andreas); J.A.J.W. Kluytmans (Jan); C.M.J.E. Vandenbroucke-Grauls (Christina); M.H.M. Meester (Marlene); P.H.J. van Keulen (Peter); H.A. Verbrugh (Henri); H.F.L. Wertheim (Heiman)

    2004-01-01

    textabstractBACKGROUND: Staphylococcus aureus nasal carriage is a major risk factor for nosocomial S. aureus infection. Studies show that intranasal mupirocin can prevent nosocomial surgical site infections. No data are available on the efficacy of mupirocin in nonsurgical

  11. ANTISTAPHYBASE: database of antimicrobial peptides (AMPs) and essential oils (EOs) against methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus aureus.

    Science.gov (United States)

    Zouhir, Abdelmajid; Taieb, Malek; Lamine, Mohamed Ashraf; Cherif, Ammar; Jridi, Taoufik; Mahjoubi, Basma; Mbarek, Sarra; Fliss, Ismail; Nefzi, Adel; Sebei, Khaled; Ben Hamida, Jeannette

    2017-03-01

    Staphylococcus aureus and methicillin-resistant S. aureus are major pathogens. The antimicrobial peptides and essential oils (EOs) display narrow- or broad-spectrum activity against bacteria including these strains. A centralized resource, such as a database, designed specifically for anti-S. aureus/anti-methicillin-resistant S. aureus antimicrobial peptides and EOs is therefore needed to facilitate the comprehensive investigation of their structure/activity associations and combinations. The database ANTISTAPHYBASE is created to facilitate access to important information on antimicrobial peptides and essential peptides against methicillin-resistant S. aureus and S. aureus. At the moment, the database contains 596 sequences of antimicrobial peptides produced by diverse organisms and 287 essential oil records. It permits a quick and easy search of peptides based on their activity as well as their general, physicochemical properties and literature data. These data are very useful to perform further bioinformatic or chemometric analysis and would certainly be useful for the development of new drugs for medical use. The ANTISTAPHYBASE database is freely available at: https://www.antistaphybase.com/ .

  12. Methicillin-resistant Staphylococcus aureus: an overview for manual therapists☆

    Science.gov (United States)

    Green, Bart N.; Johnson, Claire D.; Egan, Jonathon Todd; Rosenthal, Michael; Griffith, Erin A.; Evans, Marion Willard

    2012-01-01

    Objective Methicillin-resistant Staphylococcus aureus (MRSA) is associated with difficult-to-treat infections and high levels of morbidity. Manual practitioners work in environments where MRSA is a common acquired infection. The purpose of this review is to provide a practical overview of MRSA as it applies to the manual therapy professions (eg, physical and occupational therapy, athletic training, chiropractic, osteopathy, massage, sports medicine) and to discuss how to identify and prevent MRSA infections in manual therapy work environments. Methods PubMed and CINAHL were searched from the beginning of their respective indexing years through June 2011 using the search terms MRSA, methicillin-resistant Staphylococcus aureus, and Staphylococcus aureus. Texts and authoritative Web sites were also reviewed. Pertinent articles from the authors' libraries were included if they were not already identified in the literature search. Articles were included if they were applicable to ambulatory health care environments in which manual therapists work or if the content of the article related to the clinical management of MRSA. Results Following information extraction, 95 citations were included in this review, to include 76 peer-reviewed journal articles, 16 government Web sites, and 3 textbooks. Information was organized into 10 clinically relevant categories for presentation. Information was organized into the following clinically relevant categories: microbiology, development of MRSA, risk factors for infection, clinical presentation, diagnostic tests, screening tests, reporting, treatment, prevention for patients and athletes, and prevention for health care workers. Conclusion Methicillin-resistant S aureus is a health risk in the community and to patients and athletes treated by manual therapists. Manual practitioners can play an essential role in recognizing MRSA infections and helping to control its transmission in the health care environment and the community

  13. Role of nasal carriage of Staphylococcus aureus in chronic urticaria

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    Ashimav Deb Sharma

    2012-01-01

    Full Text Available Aim: To evaluate the role of nasal carriage of Staphylococcus aureus in patients suffering from chronic urticaria. Method: All total 82 patients were included for this study. Study group comprised 57 patients with chronic urticaria and the control group comprised 25 healthy volunteers. Nasal swab specimens were taken from all the 82 patients for bacterial culture and antimicrobial sensitivity. Patients with chronic urticaria who had positive growth for S. aureus were treated with sensitive antimicrobial agent. Nasal swab specimens were taken again from all the patients who received antimicrobial therapy to ensure complete eradication of S. aureus. All patients were followed up for a period of 6 weeks after the treatment. Urticarial activity was measured with the help of urticarial activity score. Results: S. aureus was detected in swab specimens from the nasal cavity in 32 patients in the study group and 7 patients in the control group. In the study group, after the antimicrobial treatment, 9 patients (28.12% had complete recovery from urticaria during the follow-up period; 4 patients (12.5% showed partial recovery from urticaria while the remaining patients (59.37% continued to suffer from urticaria. Conclusion: This study showed that nasal carriage of S. aureus can act as an etiological factor in chronic urticaria.

  14. The Bicomponent Pore-Forming Leucocidins of Staphylococcus aureus

    Science.gov (United States)

    Alonzo, Francis

    2014-01-01

    SUMMARY The ability to produce water-soluble proteins with the capacity to oligomerize and form pores within cellular lipid bilayers is a trait conserved among nearly all forms of life, including humans, single-celled eukaryotes, and numerous bacterial species. In bacteria, some of the most notable pore-forming molecules are protein toxins that interact with mammalian cell membranes to promote lysis, deliver effectors, and modulate cellular homeostasis. Of the bacterial species capable of producing pore-forming toxic molecules, the Gram-positive pathogen Staphylococcus aureus is one of the most notorious. S. aureus can produce seven different pore-forming protein toxins, all of which are believed to play a unique role in promoting the ability of the organism to cause disease in humans and other mammals. The most diverse of these pore-forming toxins, in terms of both functional activity and global representation within S. aureus clinical isolates, are the bicomponent leucocidins. From the first description of their activity on host immune cells over 100 years ago to the detailed investigations of their biochemical function today, the leucocidins remain at the forefront of S. aureus pathogenesis research initiatives. Study of their mode of action is of immediate interest in the realm of therapeutic agent design as well as for studies of bacterial pathogenesis. This review provides an updated perspective on our understanding of the S. aureus leucocidins and their function, specificity, and potential as therapeutic targets. PMID:24847020

  15. Virulence potential of Staphylococcus aureus isolates from Buruli ulcer patients.

    Science.gov (United States)

    Amissah, Nana Ama; Chlebowicz, Monika A; Ablordey, Anthony; Tetteh, Caitlin S; Prah, Isaac; van der Werf, Tjip S; Friedrich, Alex W; van Dijl, Jan Maarten; Stienstra, Ymkje; Rossen, John W

    2017-06-01

    Buruli ulcer (BU) is a necrotizing infection of the skin and subcutaneous tissue caused by Mycobacterium ulcerans. BU wounds may also be colonized with other microorganisms including Staphylococcus aureus. This study aimed to characterize the virulence factors of S. aureus isolated from BU patients. Previously sequenced genomes of 21 S. aureus isolates from BU patients were screened for the presence of virulence genes. The results show that all S. aureus isolates harbored on their core genomes genes for known virulence factors like α-hemolysin, and the α- and β-phenol soluble modulins. Besides the core genome virulence genes, mobile genetic elements (MGEs), i.e. prophages, genomic islands, pathogenicity islands and a Staphylococcal cassette chromosome (SCC) were found to carry different combinations of virulence factors, among them genes that are known to encode factors that promote immune evasion, superantigens and Panton-Valentine Leucocidin. The present observations imply that the S. aureus isolates from BU patients harbor a diverse repertoire of virulence genes that may enhance bacterial survival and persistence in the wound environment and potentially contribute to delayed wound healing. Copyright © 2017 The Authors. Published by Elsevier GmbH.. All rights reserved.

  16. A systematic review of animal models for Staphylococcus aureus osteomyelitis

    Science.gov (United States)

    Reizner, W.; Hunter, J.G.; O’Malley, N.T.; Southgate, R.D.; Schwarz, E.M.; Kates, S.L.

    2015-01-01

    Staphylococcus aureus (S. aureus) osteomyelitis is a significant complication for orthopaedic patients undergoing surgery, particularly with fracture fixation and arthroplasty. Given the difficulty in studying S. aureus infections in human subjects, animal models serve an integral role in exploring the pathogenesis of osteomyelitis, and aid in determining the efficacy of prophylactic and therapeutic treatments. Animal models should mimic the clinical scenarios seen in patients as closely as possible to permit the experimental results to be translated to the corresponding clinical care. To help understand existing animal models of S. aureus, we conducted a systematic search of PubMed & Ovid MEDLINE to identify in vivo animal experiments that have investigated the management of S. aureus osteomyelitis in the context of fractures and metallic implants. In this review, experimental studies are categorized by animal species and are further classified by the setting of the infection. Study methods are summarized and the relevant advantages and disadvantages of each species and model are discussed. While no ideal animal model exists, the understanding of a model’s strengths and limitations should assist clinicians and researchers to appropriately select an animal model to translate the conclusions to the clinical setting. PMID:24668594

  17. Frequency of methicillin resistant Staphylococcus aureus in health care

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    Somayeh Rahimi-Alang

    2011-03-01

    Full Text Available Background: Methicillin resistant Staphylococcus aureus (MRSA is one of the most important pathogen in hospitals. Healthcare personnel are the main source of nosocomial infections and identification and control of MRSA carriers can reduce incidence of infections. The aim of this study was to determine the prevalence of MRSA and their antibiotic susceptibility profile among healthcare workers in Gorgan.Materials and Method: 333 healthcare workers were participated in this cross-sectional study in 2009. Samples were taken with sterile cotton swabs from both anterior nares and hands. Swabs were plated immediately on to the mannitol salt agar. Suspected colonies were confirmed as S. aureus by Gram staining, catalase, coagulase and DNase tests. Minimum inhibition concentration by micro dilution broth method was used to determine methicillin resistant strains. Antimicrobial susceptibility to other antibiotics was performed according to NCCLS guidelines by disc diffusion method.Result: Frequency of S.aureus and MRSA carriers among healthcare workers was 24% and 3% respectively. The highest rate of S. aureus and MRSA carriers were observed in operating room staff. Resistance to penicillin was seen in 97.5% of isolates and all strains were sensitive to vancomycin.Conclusions: Frequency of S. aureus and MRSA in healthcare workers was median and rather low respectively. Continual monitoring and control of carriers can reduce distribution of this organism and their infections

  18. Prevalence of Staphylococcus aureus in Shrimps in Tehran during 2013

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    Mohammad Mehdi Soltan Dallal

    2016-02-01

    Full Text Available Background During fishing and transport, preservation and quality of fish products are importantas well as storage to prevent the growth of pathogenic and toxin producing bacteria.Staphylococcus aureus is one of the most common causes of sea food-borne diseases worldwidedue to contamination of food by preformed enterotoxins. The aim of this study was to compare theprevalence and contamination of S. aureus in marine and farmed shrimps in Tehran fishery center.Methods: A total of 300 samples, including 150 marine, 150 farmed shrimps were selected duringSeptember 2013 to December 2014. Isolation and identification of S. aureus from isolated sampleswere carried out according to conventional methods, and antibiotic susceptibility test wasperformed by modified Kirby-Bauer disc diffusion method.Results: The results of this study showed that 30% of marine and 20% off armed shrimps werecontaminated with S. aureus. The highest resistance was observed with penicillin and ampicillin,whereas 100% were sensitive to vancomycin, clindamycin, ciprofloxacin, and rifampin.Conclusions: Due to relatively high contamination of shrimp by S. aureus more attention shouldbe given during processing and manufacturing.

  19. Antibacterial Action of Curcumin against Staphylococcus aureus: A Brief Review

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    Sin-Yeang Teow

    2016-01-01

    Full Text Available Curcumin, the major constituent of Curcuma longa L. (Zingiberaceae family or turmeric, commonly used for cooking in Asian cuisine, is known to possess a broad range of pharmacological properties at relatively nontoxic doses. Curcumin is found to be effective against Staphylococcus aureus (S. aureus. As demonstrated by in vitro experiment, curcumin exerts even more potent effects when used in combination with various other antibacterial agents. Hence, curcumin which is a natural product derived from plant is believed to have profound medicinal benefits and could be potentially developed into a naturally derived antibiotic in the future. However, there are several noteworthy challenges in the development of curcumin as a medicine. S. aureus infections, particularly those caused by the multidrug-resistant strains, have emerged as a global health issue and urgent action is needed. This review focuses on the antibacterial activities of curcumin against both methicillin-sensitive S. aureus (MSSA and methicillin-resistant S. aureus (MRSA. We also attempt to highlight the potential challenges in the effort of developing curcumin into a therapeutic antibacterial agent.

  20. Prevalence of Staphylococcus aureus in Shrimps in Tehran during 2013

    Directory of Open Access Journals (Sweden)

    Mohammad Mehdi Soltan Dallal

    2015-12-01

    Full Text Available Background During fishing and transport, preservation and quality of fish products are importantas well as storage to prevent the growth of pathogenic and toxin producing bacteria.Staphylococcus aureus is one of the most common causes of sea food-borne diseases worldwidedue to contamination of food by preformed enterotoxins. The aim of this study was to compare theprevalence and contamination of S. aureus in marine and farmed shrimps in Tehran fishery center.Methods: A total of 300 samples, including 150 marine, 150 farmed shrimps were selected duringSeptember 2013 to December 2013. Isolation and identification of S. aureus from isolated sampleswere carried out according to conventional methods, and antibiotic susceptibility test wasperformed by modified Kirby-Bauer disc diffusion methodResults: The results of this study showed that 30% of marine and 20% off armed shrimps werecontaminated with S. aureus. The highest resistance was observed with penicillin and ampicillin,whereas 100% were sensitive to vancomycin, clindamycin, ciprofloxacin, and rifampin.Conclusions: Due to relatively high contamination of shrimp by S. aureus more attention shouldbe given during processing and manufacturing.

  1. Staphylococcus aureus small colony variants in diabetic foot infections

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    Estrella Cervantes-García

    2015-03-01

    Full Text Available Background: Staphylococcus aureus (S. aureus is one of the major pathogens causing chronic infections. The ability of S. aureus to acquire resistance to a diverse range of antimicrobial compounds results in limited treatment options, particularly in methicillin-resistant S. aureus (MRSA. A mechanism by which S. aureus develops reduced susceptibility to antimicrobials is through the formation of small colony variants (SCVs. Infections by SCVs of S. aureus are an upcoming problem due to difficulties in laboratory diagnosis and resistance to antimicrobial therapy. Methods: A prospective study was performed on 120 patients diagnosed with both type 2 diabetes mellitus and infected diabetic foot ulcers. The study was carried out from July 2012 to December 2013 in Hospital General de Mexico. The samples were cultured in blood agar, mannitol salt agar, and MacConkey agar media, and incubated at 37°C in aerobic conditions. Results: We describe the first known cases of diabetic foot infections caused by MRSA-SCVs in patients diagnosed with type 2 diabetes mellitus and infected diabetic foot ulcers. In all of our cases, the patients had not received any form of gentamicin therapy. Conclusions: The antibiotic therapy commonly used in diabetic patients with infected diabetic foot ulcers fails in the case of MRSA-SCVs because the intracellular location protects S. aureus-SCVs from the host's defenses and also helps them resist antibiotics. The cases studied in this article add to the spectrum of persistent and relapsing infections attributed to MRSA-SCVs and emphasizes that these variants may also play a relevant role in diabetic foot infections.

  2. Staphylococcus aureus small colony variants in diabetic foot infections.

    Science.gov (United States)

    Cervantes-García, Estrella; García-Gonzalez, Rafael; Reyes-Torres, Angélica; Resendiz-Albor, Aldo Arturo; Salazar-Schettino, Paz María

    2015-01-01

    Background : Staphylococcus aureus (S. aureus) is one of the major pathogens causing chronic infections. The ability of S. aureus to acquire resistance to a diverse range of antimicrobial compounds results in limited treatment options, particularly in methicillin-resistant S. aureus (MRSA). A mechanism by which S. aureus develops reduced susceptibility to antimicrobials is through the formation of small colony variants (SCVs). Infections by SCVs of S. aureus are an upcoming problem due to difficulties in laboratory diagnosis and resistance to antimicrobial therapy. Methods : A prospective study was performed on 120 patients diagnosed with both type 2 diabetes mellitus and infected diabetic foot ulcers. The study was carried out from July 2012 to December 2013 in Hospital General de Mexico. The samples were cultured in blood agar, mannitol salt agar, and MacConkey agar media, and incubated at 37°C in aerobic conditions. Results : We describe the first known cases of diabetic foot infections caused by MRSA-SCVs in patients diagnosed with type 2 diabetes mellitus and infected diabetic foot ulcers. In all of our cases, the patients had not received any form of gentamicin therapy. Conclusions : The antibiotic therapy commonly used in diabetic patients with infected diabetic foot ulcers fails in the case of MRSA-SCVs because the intracellular location protects S. aureus-SCVs from the host's defenses and also helps them resist antibiotics. The cases studied in this article add to the spectrum of persistent and relapsing infections attributed to MRSA-SCVs and emphasizes that these variants may also play a relevant role in diabetic foot infections.

  3. Staphylococcus aureus from the German general population is highly diverse.

    Science.gov (United States)

    Becker, Karsten; Schaumburg, Frieder; Fegeler, Christian; Friedrich, Alexander W; Köck, Robin

    2017-01-01

    This prospective cohort study evaluates colonization dynamics and molecular characteristics of methicillin-susceptible and - resistant Staphylococcus aureus (MSSA/MRSA) in a German general population. Nasal swabs of 1878 non-hospitalized adults were screened for S. aureus. Participants were screened thrice in intervals of 6-8 months. Isolates were characterized by spa and agr typing, mecA and mecC possession, respectively, and PCRs targeting virulence factors. 40.9% of all participants carried S. aureus at least once while 0.7% of the participants carried MRSA (mainly spa t011). MSSA isolates (n=1359) were associated with 331 different spa types; t084 (7.7%), t091 (6.1%) and t012 (71, 5.2%) were predominant. Of 206 participants carrying S. aureus at all three sampling time points, 14.1% carried the same spa type continuously; 5.3% carried different spa types with similar repeat patterns, but 80.6% carried S. aureus with unrelated spa types. MSSA isolates frequently harboured genes encoding enterotoxins (sec: 16.6%, seg: 63.1%, sei: 64.5%) and toxic shock syndrome toxin (tst: 17.5%), but rarely Panton-Valentine leukocidin (lukS-PV/lukF-PV: 0.2%). MSSA colonizing human nares in the community are clonally highly diverse. Among those constantly carrying S. aureus, clonal lineages changed over time. The proportion of persistent S. aureus carriers was lower than reported elsewhere. Copyright © 2016 Elsevier GmbH. All rights reserved.

  4. Ecological Overlap and Horizontal Gene Transfer in Staphylococcus aureus and Staphylococcus epidermidis.

    Science.gov (United States)

    Méric, Guillaume; Miragaia, Maria; de Been, Mark; Yahara, Koji; Pascoe, Ben; Mageiros, Leonardos; Mikhail, Jane; Harris, Llinos G; Wilkinson, Thomas S; Rolo, Joana; Lamble, Sarah; Bray, James E; Jolley, Keith A; Hanage, William P; Bowden, Rory; Maiden, Martin C J; Mack, Dietrich; de Lencastre, Hermínia; Feil, Edward J; Corander, Jukka; Sheppard, Samuel K

    2015-04-16

    The opportunistic pathogens Staphylococcus aureus and Staphylococcus epidermidis represent major causes of severe nosocomial infection, and are associated with high levels of mortality and morbidity worldwide. These species are both common commensals on the human skin and in the nasal pharynx, but are genetically distinct, differing at 24% average nucleotide divergence in 1,478 core genes. To better understand the genome dynamics of these ecologically similar staphylococcal species, we carried out a comparative analysis of 324 S. aureus and S. epidermidis genomes, including 83 novel S. epidermidis sequences. A reference pan-genome approach and whole genome multilocus-sequence typing revealed that around half of the genome was shared between the species. Based on a BratNextGen analysis, homologous recombination was found to have impacted on 40% of the core genes in S. epidermidis, but on only 24% of the core genes in S. aureus. Homologous recombination between the species is rare, with a maximum of nine gene alleles shared between any two S. epidermidis and S. aureus isolates. In contrast, there was considerable interspecies admixture of mobile elements, in particular genes associated with the SaPIn1 pathogenicity island, metal detoxification, and the methicillin-resistance island SCCmec. Our data and analysis provide a context for considering the nature of recombinational boundaries between S. aureus and S. epidermidis and, the selective forces that influence realized recombination between these species. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  5. Predictors of Staphylococcus aureus Colonization and Results after Decolonization

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    Tennison L. Malcolm

    2016-01-01

    Full Text Available Protocols for the screening and decolonization of Staphylococcus aureus prior to total joint arthroplasty (TJA have become widely adopted. The goals of this study were to determine: (1 whether implementation of a screening protocol followed by decolonization with mupirocin/vancomycin and chlorhexidine reduces the risk of revision compared with no screening protocol (i.e., chlorhexidine alone and (2 whether clinical criteria could reliably predict colonization with MSSA and/or MRSA. Electronic medical records of primary patients undergoing TJA that were screened (n=3,927 and were not screened (n=1,751 for Staphylococcus aureus at least 4 days prior to surgery, respectively, were retrospectively reviewed. All patients received chlorhexidine body wipes preoperatively. Patients carrying MSSA and MRSA were treated preoperatively with mupirocin and vancomycin, respectively, along with the standard preoperative antibiotics and chlorhexidine body wipes. Screened patients were 50% less likely to require revision due to prosthetic joint infection compared to those not screened (p=0.04. Multivariate regression models were poorly accurate in predicting colonization with MSSA (AUC = 0.58 and MRSA (AUC = 0.62. These results support the routine screening and decolonization of S. aureus prior to TJA.

  6. [Genotypic and phenotypic analysis of hemolysis in foodborne Staphylococcus aureus].

    Science.gov (United States)

    Wei, Peinan; Lü, Guoping; Xu, Baohong

    2012-11-01

    To establish a multiplex PCR method for detecting genes of (alpha-hemolysin (hla), beta-hemolysin (hlb), hemolysin and 16S rDNA, and to learn the distribution of three hemolysin genes and the characteristics of hemolytic phenotype in 148 foodborne Staphylococcus aureus strains, and to classify the strains with cluster analysis. The multiplex PCR method was established and used to detect the genes of alpha-hemolysin, beta-hemolysin, hemolysin and 16S rDNA. The blood agar method was used to detect the characteristics of hemolytic phenotype. The experiment data was analyed with SPSS16.0. 131 strains were positive for hla gene (88.51%), 90 hlb gene (60.81%), 28 hemolysin gene (18.92%). 131 strains had the characteristics of hemolysis (88.51%), while the hemolysis were negative in 17 strains (11.49%). With the clustering factors of the hemolysin genotype and hemolytic phenotype, 148 strains were classified into 12 types from type A to type L with 100% similarity. Among them, type A contained 58 strains (39.19%), type B 37 (25.00%), type C 18 (12.16%). This multiplex PCR method is fast, convenient and specific, and could be used for high-throughput screening of hemolysin genes in S. aureus. Most of the foodborne Staphylococcus aureus strains carrying the hla gene mainly belong to type A and type B.

  7. Ocorrência de Staphylococcus aureus em queijo tipo "frescal"

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    Almeida Filho Edvaldo Sampaio de

    2000-01-01

    Full Text Available OBJETIVO: Verificar a ocorrência de Staphylococcus aureus em uma amostra de queijo tipo Minas "frescal" comercializado na cidade de Poços de Caldas, MG, de modo a obter subsídios que permitam avaliar o risco potencial que este produto pode representar para a saúde da população consumidora. MÉTODOS: Foi investigada a presença e o número de cepas de Staphylococcus aureus em 80 amostras de queijo tipo Minas "frescal" produzido artesanalmente e comercializado na cidade de Poços de Caldas, MG, Brasil. RESULTADOS: Os resultados obtidos evidenciaram a presença de S. aureus em 40 (50,0% amostras, cujas contagens revelaram valores médios em torno de 10(5/g. CONCLUSÕES: Tais achados parecem ser extremamente preocupantes, pois além de se situarem acima do limite máximo de 10³/g estabelecido pelo Ministério da Saúde, estes valores mostraram-se muito próximos dos requeridos para a produção de enterotoxinas em quantidades suficientes para a ocorrência de surtos de intoxicação alimentar estafilocócica.

  8. Meningitis associated with Vancomycin resistant Enterococcus casseliflavus: First report

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    Nilay Sefa Uçar

    2011-12-01

    Full Text Available Enterococci are present in the gastrointestinal system as normal floral components. In the past two decades membersof the genus Enterococcus have emerged as important nosocomial pathogens worldwide. Enterococci may cause arange of different disorders such as urinary tract, intraabdominal, and wound infections, as well as endocarditis, meningitisand bacteraemia. Nosocomial enterococcal meningitis is most commonly observed following ventriculoperitonealshunt operations. Vancomycin resistant enterococcus (VRE represents 30% of all enterococci infections.This report presents a vancomycin-resistant Enterococcus casseliflavus meningitis case in a 66-year-old patient withventriculoperitoneal shunt, which has not been reported in the literature before. Successful outcomes were obtainedwith daptomycin plus linezolid combined treatment in VRE meningitis. Treatment recommendations in VRE meningitisare also discussed in this article. J Microbiol Infect Dis 2011;1 (3:138-140

  9. Biofilm-forming ability profiling of Staphylococcus aureus and Staphylococcus epidermidis mastitis isolates

    DEFF Research Database (Denmark)

    Oliveira, M; Bexiga, R; Nunes, S F

    2006-01-01

    Biofilm-forming ability has been increasingly recognized as an important virulence factor in Staphylococci, facilitating their persistence in the host, evading its defences and allowing bacterial survival at high antimicrobial concentrations. Staphylococcus aureus remains a major pathogen...... of chronic mastitis, but in the last years Staphylococcus epidermidis has emerged as a relevant mastitis pathogen. The present work aimed at the evaluation of the biofilm-forming ability of Staphylococci field isolates from bovine subclinical mastitis and at the development of a fluorescent in situ...

  10. Whole Genome Sequencing of Danish Staphylococcus argenteus Reveals a Genetically Diverse Collection with Clear Separation from Staphylococcus aureus.

    Science.gov (United States)

    Hansen, Thomas A; Bartels, Mette D; Høgh, Silje V; Dons, Lone E; Pedersen, Michael; Jensen, Thøger G; Kemp, Michael; Skov, Marianne N; Gumpert, Heidi; Worning, Peder; Westh, Henrik

    2017-01-01

    Staphylococcus argenteus (S. argenteus) is a newly identified Staphylococcus species that has been misidentified as Staphylococcus aureus (S. aureus) and is clinically relevant. We identified 25 S. argenteus genomes in our collection of whole genome sequenced S. aureus. These genomes were compared to publicly available genomes and a phylogeny revealed seven clusters corresponding to seven clonal complexes. The genome of S. argenteus was found to be different from the genome of S. aureus and a core genome analysis showed that ~33% of the total gene pool was shared between the two species, at 90% homology level. An assessment of mobile elements shows flow of SCCmec cassettes, plasmids, phages, and pathogenicity islands, between S. argenteus and S. aureus. This dataset emphasizes that S. argenteus and S. aureus are two separate species that share genetic material.

  11. Whole Genome Sequencing of Danish Staphylococcus argenteus Reveals a Genetically Diverse Collection with Clear Separation from Staphylococcus aureus

    DEFF Research Database (Denmark)

    Hansen, Thomas A; Bartels, Mette D; Høgh, Silje V

    2017-01-01

    Staphylococcus argenteus (S. argenteus) is a newly identified Staphylococcus species that has been misidentified as Staphylococcus aureus (S. aureus) and is clinically relevant. We identified 25 S. argenteus genomes in our collection of whole genome sequenced S. aureus. These genomes were compared...... to publicly available genomes and a phylogeny revealed seven clusters corresponding to seven clonal complexes. The genome of S. argenteus was found to be different from the genome of S. aureus and a core genome analysis showed that ~33% of the total gene pool was shared between the two species, at 90......% homology level. An assessment of mobile elements shows flow of SCCmec cassettes, plasmids, phages, and pathogenicity islands, between S. argenteus and S. aureus. This dataset emphasizes that S. argenteus and S. aureus are two separate species that share genetic material....

  12. Whole Genome Sequencing of Danish Staphylococcus argenteus Reveals a Genetically Diverse Collection with Clear Separation from Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Thomas A. Hansen

    2017-08-01

    Full Text Available Staphylococcus argenteus (S. argenteus is a newly identified Staphylococcus species that has been misidentified as Staphylococcus aureus (S. aureus and is clinically relevant. We identified 25 S. argenteus genomes in our collection of whole genome sequenced S. aureus. These genomes were compared to publicly available genomes and a phylogeny revealed seven clusters corresponding to seven clonal complexes. The genome of S. argenteus was found to be different from the genome of S. aureus and a core genome analysis showed that ~33% of the total gene pool was shared between the two species, at 90% homology level. An assessment of mobile elements shows flow of SCCmec cassettes, plasmids, phages, and pathogenicity islands, between S. argenteus and S. aureus. This dataset emphasizes that S. argenteus and S. aureus are two separate species that share genetic material.

  13. Colonization of nursing professionals by Staphylococcus aureus La colonización de los profesionales de enfermería por Staphylococcus aureus A colonização dos profissionais de enfermagem por Staphylococcus aureus

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    Josely Pinto de Moura

    2011-04-01

    Full Text Available This cross-sectional study aimed to investigate the presence of Staphylococcus aureus in the saliva of the nursing team of a teaching hospital in the interior of São Paulo State. Three saliva samples were collected from 351 individuals with an interval of two months between each collection. All ethical aspects were considered. In 867 (82.3% cultures there was no identification of Staphylococcus aureus in the saliva, in 88 (17.7% cultures Staphylococcus aureus was isolated, 26 (2.5% of which were resistant to methicillin. The prevalence of professionals colonized by Staphylococcus aureus was 41.0% (144/351, of which 7.1% (25/351 were characterized as methicillin-resistant Staphylococcus aureus. Transient carriers represented 81.2% and persistent carriers 18.8%. Resistance to mupirocin was 73.1% of MRSA and 9.3% of MSSA. The results demonstrate that it is the nurse and nursing technician that are the professional categories most susceptible to MRSA. Broader discussion on the thematic and interventions are needed.Se trata de un estudio transversal que tuvo como objetivo investigar la presencia de Staphylococcus aureus en la saliva del equipo de enfermería de un hospital escuela del interior del estado de Sao Paulo. Fueron recolectadas tres muestras de saliva de 351 individuos con intervalo de dos meses. Todos los aspectos éticos fueron contemplados. En 867 (82,3% culturas no hubo identificación de Staphylococcus aureus en la saliva, en 88 (17,7% culturas fue aislado Staphylococcus aureus, siendo 26 (2,5% resistentes a la meticilina. La prevalencia de profesionales colonizados por Staphylococcus aureus fue de 41,0% (144/351, de los cuales 7,1% (25/351 fueron caracterizados como Staphylococcus aureus resistentes a la meticilina. Los portadores transitorios representaron 81,2% y los persistentes 18,8%. La resistencia a la mupirocina fue de 73,1% entre los resistentes a la meticilina y 9,3% en los sensibles a la meticilina. Los resultados

  14. Staphylococcus aureus detection in the mouth of housekeepers Detección de Staphylococcus aureus en la boca de trabajadores de la limpieza hospitalaria Detecção de Staphylococcus aureus na boca de trabalhadores da limpeza hospitalar

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    Elaine Drehmer de Almeida Cruz

    2011-02-01

    Full Text Available This study assessed the prevalence of colonization by Staphylococcus aureus in hospital housekeepers, and their knowledge and beliefs regarding this problem. Three saliva samples were collected and a questionnaire regarding knowledge and beliefs was applied. Of the 92 workers, 63 (68.5% participated in the study; 20 were not and 43 were colonized; 13 by methicillin resistant Staphylococcus aureus and 30 by methicillin sensitive Staphylococcus aureus. Persistent carrier status of methicillin resistant Staphylococcus aureus was detected in 15.4% of cases. Low knowledge and perception of occupational risk were observed. The mouth was identified as an important reservoir of methicillin resistant Staphylococcus aureus. Analyzing knowledge and beliefs, as well as the state of carrier, is an important strategy to be added to educational actions for the prevention of workers' colonization.Este estudio evaluó la prevalencia de la colonización por Staphylococcus aureus en trabajadores de limpieza hospitalaria, y su conocimiento y creencias acerca de la problemática. Fueron recolectadas tres muestras de saliva y aplicado un cuestionario referente al conocimiento y creencias. De 92 trabajadores, 63 (68,5% participaron del estudio; 20 se presentaron no colonizados y 43 colonizados; 13 para Staphylococcus aureus resistente a la meticilina y 30 para Staphylococcus aureus sensibles a la meticilina. El estado de portador persistente por Staphylococcus aureus resistente a la meticilina fue detectado en 15,4% de los casos. Bajo conocimiento y percepción del riesgo ocupacional fueron observados. La boca fue identificada como importante reservatorio de Staphylococcus aureus resistente a la meticilina. Analizar el conocimiento y creencias juntamente con la investigación del estado de portador es una importante estrategia a ser agregada a las acciones educativas para la prevención de la colonización de trabajadores.Este estudo avaliou a prevalência da coloniza

  15. Highly sensitive detection of Staphylococcus aureus directly from patient blood.

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    Padmapriya P Banada

    Full Text Available Rapid detection of bloodstream infections (BSIs can be lifesaving. We investigated the sample processing and assay parameters necessary for highly-sensitive detection of bloodstream bacteria, using Staphylococcus aureus as a model pathogen and an automated fluidic sample processing-polymerase chain reaction (PCR platform as a model diagnostic system.We compared a short 128 bp amplicon hemi-nested PCR and a relatively shorter 79 bp amplicon nested PCR targeting the S. aureus nuc and sodA genes, respectively. The sodA nested assay showed an enhanced limit of detection (LOD of 5 genomic copies per reaction or 10 colony forming units (CFU per ml blood over 50 copies per reaction or 50 CFU/ml for the nuc assay. To establish optimal extraction protocols, we investigated the relative abundance of the bacteria in different components of the blood (white blood cells (WBCs, plasma or whole blood, using the above assays. The blood samples were obtained from the patients who were culture positive for S. aureus. Whole blood resulted in maximum PCR positives with sodA assay (90% positive as opposed to cell-associated bacteria (in WBCs (71% samples positive or free bacterial DNA in plasma (62.5% samples positive. Both the assays were further tested for direct detection of S. aureus in patient whole blood samples that were contemporaneous culture positive. S. aureus was detected in 40/45 of culture-positive patients (sensitivity 89%, 95% CI 0.75-0.96 and 0/59 negative controls with the sodA assay (specificity 100%, 95% CI 0.92-1.We have demonstrated a highly sensitive two-hour assay for detection of sepsis causing bacteria like S. aureus directly in 1 ml of whole blood, without the need for blood culture.

  16. New epidemiology of Staphylococcus aureus infection in Asia.

    Science.gov (United States)

    Chen, C-J; Huang, Y-C

    2014-07-01

    Not only is Asia the most populous region in the world, but inappropriate therapy, including self-medication with over-the-counter antimicrobial agents, is a common response to infectious diseases. The high antibiotic selective pressure among the overcrowded inhabitants creates an environment that is suitable for the rapid development and efficient spread of numerous multidrug-resistant pathogens. Indeed, Asia is among the regions with the highest prevalence rates of healthcare-associated methicillin-resistant Staphylococcus aureus (HA-MRSA) and community-associated methicillin-resistant S. aureus (CA-MRSA) in the world. Most hospitals in Asia are endemic for multidrug-resistant methicillin-resistant S. aureus (MRSA), with an estimated proportion from 28% (in Hong Kong and Indonesia) to >70% (in Korea) among all clinical S. aureus isolates in the early 2010s. Isolates with reduced susceptibility or a high level of resistance to glycopeptides have also been increasingly identified in the past few years. In contrast, the proportion of MRSA among community-associated S. aureus infections in Asian countries varies markedly, from 35%. Two pandemic HA-MRSA clones, namely multilocus sequence type (ST) 239 and ST5, are disseminated internationally in Asia, whereas the molecular epidemiology of CA-MRSA in Asia is characterized by clonal heterogeneity, similar to that in Europe. In this review, the epidemiology of S. aureus in both healthcare facilities and communities in Asia is addressed, with an emphasis on the prevalence, clonal structure and antibiotic resistant profiles of the MRSA strains. The novel MRSA strains from livestock animals have been considered to constitute a public health threat in western countries. The emerging livestock-associated MRSA strains in Asia are also included in this review. © 2014 The Authors Clinical Microbiology and Infection © 2014 European Society of Clinical Microbiology and Infectious Diseases.

  17. UJI BIOAKTIVITAS FORBAZOL E TERHADAP HAMBATAN PERTUMBUHAN PADA STAPHYLOCOCCUS AUREUS

    Directory of Open Access Journals (Sweden)

    Ni Putu Ristiati

    2015-05-01

    Full Text Available Forbazol E dapat disintesis dari 1-(p-tosil pirol-2-karbonil klorida dan fenasil amonium klorida dengan rendeman cukup tinggi melalui empat tahap reaksi yaitu : pertama, reaksi penggabungan; kedua, siklodehidrasi; ketiga,hidrolisis; dan keempat, klorinasi. Staphylococcus aureus merupakan bakteri gram positif. Untuk itu perlu diteliti : (a forbazol E dapat menghambat pertumbuhan S. aureus ; (b konsentrasi forbazol E 75 mg/L akan menimbulkan hambatan pertumbuhan S. aureus lebih tinggi dari konsentrasi 37,5 mg/L. Penelitian eksperimental ini menggunakan rancangan the randomized- posttest-only control group design dan melibatkan 9 sampel pada kelompok kontrol, 9 sampel pada kelompok perlakuan I dan 9 sampel pada perlakuan II. Data yang diperoleh dianalisis dengan menggunakan uji anova pada taraf signifikansi 5%. Hasil penelitian membuktikan forbazol E dapat menghambat pertumbuhan, pemberian  forbazol E pada  pada kelompok perlakuan II dengan konsentrasi 75 mg/L menimbulkan    hambatan     pertumbuhan    S. aureus lebih    tinggi dibandingkan dengan kelompok perlakuan I dengan konsentrasi 37,5 mg/L (p<0,05, uji lanjutan dengan uji beda nyata terkecil (BNT pada taraf  signifikansi  5% diperoleh  bahwa  hambatan  pertumbuhan S. aureus pada kelompok perlakuan II (75 mg/L berbeda bermakna dengan kelompok perlakuan I (37,5 mg/L (p<0,05. Bertolak dari pembahasan di atas dapat disimpulkan bahwa bioaktivitas forbazol E dapat menghambat pertumbuhan   S. aureus.

  18. Methicillin-resistant Staphylococcus aureus in human milk

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    FR Novak

    2000-01-01

    Full Text Available We collected and analyzed 500 samples of human milk, from five Brazilian cities (100 from each to detect methicillin-resistant strains of Staphylococcus aureus (MRSA producing enterotoxins. We found 57 strains of MRSA, and the mecA gene, responsible for resistance, was detected in all of them using a specific molecular probe. We examined 40 strains for the presence of four enterotoxins, after selecting a subset that included all strains from each region, except for the largest sample, from which 10 were randomly selected. Among these two presented enterotoxin B, and growth in human colostrum and trypicase soy broth. After 5 h of incubation at 37°C, population sizes were already higher than 9.4 x 105 UFC/ml and enterotoxin was released into culture medium and colostrum. Our results stress the importance of hygiene, sanitary measures, and appropriate preservation conditions to avoid the proliferation of S. aureus in human milk.

  19. Community-Associated Methicillin-Resistant Staphylococcus aureus Case Studies

    Science.gov (United States)

    Sowash, Madeleine G.; Uhlemann, Anne-Catrin

    2014-01-01

    Over the past decade, the emergence of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has changed the landscape of S. aureus infections around the globe. Initially recognized for its ability to cause disease in young and healthy individuals without healthcare exposures as well as for its distinct genotype and phenotype, this original description no longer fully encompasses the diversity of CA-MRSA as it continues to expand its niche. Using four case studies, we highlight a wide range of the clinical presentations and challenges of CA-MRSA. Based on these cases we further explore the globally polygenetic background of CA-MRSA with a special emphasis on generally less characterized populations. PMID:24085688

  20. Staphylococcus aureus Infections: Epidemiology, Pathophysiology, Clinical Manifestations, and Management

    Science.gov (United States)

    Davis, Joshua S.; Eichenberger, Emily; Holland, Thomas L.

    2015-01-01

    SUMMARY Staphylococcus aureus is a major human pathogen that causes a wide range of clinical infections. It is a leading cause of bacteremia and infective endocarditis as well as osteoarticular, skin and soft tissue, pleuropulmonary, and device-related infections. This review comprehensively covers the epidemiology, pathophysiology, clinical manifestations, and management of each of these clinical entities. The past 2 decades have witnessed two clear shifts in the epidemiology of S. aureus infections: first, a growing number of health care-associated infections, particularly seen in infective endocarditis and prosthetic device infections, and second, an epidemic of community-associated skin and soft tissue infections driven by strains with certain virulence factors and resistance to β-lactam antibiotics. In reviewing the literature to support management strategies for these clinical manifestations, we also highlight the paucity of high-quality evidence for many key clinical questions. PMID:26016486

  1. [Staphylococcus aureus prostatic abscess and subdural empyema: a case report].

    Science.gov (United States)

    Cabrera Meirás, F; Sanchís Bonet, A; Blanco Carballo, O; Martín Parada, A; Duque Ruiz, G; Leiva Galvis, O

    2007-05-01

    To report one case of prostatic abscess and subdural empyema by Staphylococcus aureus. We describe the case of a 51 year old male patient who was diagnosed of prostatic abscess and subdural empyema by Staphilococcus aureus. We use clinical presentation and physical exploration based on rectal digital examination, as diagnostic approach method. And computerized axial tomography and transrectal ultrasonography, which allows the guided needle drainage of the abscess, as diagnostic confirmation methods. The clinical picture resolved with the transrectal ultrasonography guided needle aspiration of the abscess and conservative treatment with antibiotics and urinary diversion. Prostatic abscess is an uncommon entity nowadays. Provided the great variety of symptoms, a great degree of clinical suspicion is needed for the diagnosis, and once it is got it, immediate aggressive treatment must be initiated. Transrectal ultrasonography allows not only the diagnosis, but also the drainage of the abscess. The culture of the obtained material identifies the etiological agent and the most specific antibiotic therapy.

  2. Staphylococcus aureus endocarditis and pyomyositis: Rare complications of rotavirus gastroenteritis.

    Science.gov (United States)

    Aldemir-Kocabaş, Bilge; Karbuz, Adem; Kara, Tuğçe Tural; Çiftçi, Ömer; Uçar, Tayfun; Fitöz, Suat; Çiftçi, Ergin; İnce, Erdal

    2015-08-01

    Rotavirus may cause life-threatening complications in untreated patients during the course of gastroenteritis. Electrolyte imbalance, bacteremia and sepsis are the most common complications of rotavirus gastroenteritis (RG). It is believed that translocation of intestinal microorganisms as a result of intestinal epithelium dysfunction is the underlying mechanism of bacteremia in RG. Although Gram-negative bacteremia has been noted as a complication in RG, Staphylococcus aureus bacteremia and endocarditis have not been reported previously. A 22-month-old boy was admitted with complaints of fever, diarrhea and dehydration. He was diagnosed with RG complicated with S. aureus bacteremia, pyomyositis and endocarditis. We call attention to these complications in patients with prolonged or late-onset fever during RG as rare complications of the disease. © 2015 Japan Pediatric Society.

  3. Epidemic Increase in Methicillin-resistant Staphylococcus aureus in Copenhagen

    DEFF Research Database (Denmark)

    Westh, Henrik; Boye, Kit; Bartels, Mette Damkjær

    2006-01-01

    INTRODUCTION: We have found an epidemic increase in methicillin-resistant Staphylococcus aureus (MRSA) in Copenhagen. The increase has a complex background and involves hospitals, nursing homes and persons nursed in their own home. MATERIAL AND METHODS: We found 33 MRSA patients in 2003 and 121...... in 2004. All isolates have been spa-typed and epidemiologic information collected. RESULTS: The number of MRSA cases has a doubling time of about six months. The epidemic has been caused by many different MRSA types and 31 staphylococcus protein A genotypes (spa types). MRSA has caused several hospital...... outbreaks and is endemic in 10 nursing homes. Five staff members from nursing homes have been infected with MRSA. MRSA commonly causes skin and soft tissue infections (76%), but serious infections such as septicaemia and pneumonia are also found. CONCLUSION: Treatment of MRSA-infected patients is costly due...

  4. Staphylococcus aureus redirects central metabolism to increase iron availability.

    Directory of Open Access Journals (Sweden)

    David B Friedman

    2006-08-01

    Full Text Available Staphylococcus aureus pathogenesis is significantly influenced by the iron status of the host. However, the regulatory impact of host iron sources on S. aureus gene expression remains unknown. In this study, we combine multivariable difference gel electrophoresis and mass spectrometry with multivariate statistical analyses to systematically cluster cellular protein response across distinct iron-exposure conditions. Quadruplicate samples were simultaneously analyzed for alterations in protein abundance and/or post-translational modification state in response to environmental (iron chelation, hemin treatment or genetic (Deltafur alterations in bacterial iron exposure. We identified 120 proteins representing several coordinated biochemical pathways that are affected by changes in iron-exposure status. Highlighted in these experiments is the identification of the heme-regulated transport system (HrtAB, a novel transport system which plays a critical role in staphylococcal heme metabolism. Further, we show that regulated overproduction of acidic end-products brought on by iron starvation decreases local pH resulting in the release of iron from the host iron-sequestering protein transferrin. These findings reveal novel strategies used by S. aureus to acquire scarce nutrients in the hostile host environment and begin to define the iron and heme-dependent regulons of S. aureus.

  5. Metastatic Spreading of Community Acquired Staphylococcus aureus Bacteraemia

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    Giovanna Fabio

    2011-01-01

    Full Text Available A 29-year-old woman presented to the Fondazione IRCCS “Cà Granda” Ospedale Maggiore, a tertiary care university hospital in Milan (Italy, with skin lesions, fever, myalgia, joint pain and swelling, and a one-week history of low back pain. The diagnosis was Staphylococcus aureus (S. aureus bacteraemia spreading to skin, bones, and joints and a lumbosacral epidural abscess L5-S2. Neither initial focus nor predisposing conditions were apparent. The antibiotic therapy was prolonged for six-weeks with the resolution of fever, skin lesions, articular inflammation, and the epidural abscess. Community-acquired S. aureus infections can affect patients without traditional healthcare-associated risk factors, and community acquisition is a risk-factor for the development of complications. Raised awareness of S. aureus bacteraemia, also in patients without healthcare-associated risk factors, is important in the diagnosis, management, and control of this infection, because failure to recognise patients with serious infection and lack of understanding of empirical antimicrobial selection are associated with a high mortality rate in otherwise healthy people.

  6. Staphylococcus aureus colonization related to severity of hand eczema.

    Science.gov (United States)

    Mernelius, S; Carlsson, E; Henricson, J; Löfgren, S; Lindgren, P-E; Ehricht, R; Monecke, S; Matussek, A; Anderson, C D

    2016-08-01

    Knowledge on Staphylococcus aureus colonization rates and epidemiology in hand eczema is limited. The aim of this study was to clarify some of these issues. Samples were collected by the "glove juice" method from the hands of 59 patients with chronic hand eczema and 24 healthy individuals. Swab samples were taken from anterior nares and throat from 43 of the 59 patients and all healthy individuals. S. aureus were spa typed and analysed by DNA-microarray-based genotyping. The extent of the eczema was evaluated by the hand eczema extent score (HEES). The colonization rate was higher on the hands of hand eczema patients (69 %) compared to healthy individuals (21 %, p eczema (HEES ≥ 13) had a significantly higher S. aureus density on their hands compared to those with milder eczema (HEES = 1 to 12, p = 0.004). There was no difference between patients and healthy individuals regarding colonization rates in anterior nares or throat. spa typing and DNA-microarray-based genotyping indicated certain types more prone to colonize eczematous skin. Simultaneous colonization, in one individual, with S. aureus of different types, was identified in 60-85 % of the study subjects. The colonization rate and density indicate a need for effective treatment of eczema and may have an impact on infection control in healthcare.

  7. Antimicrobial effect of different types of honey on Staphylococcus aureus

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    Saad B. Almasaudi

    2017-09-01

    Full Text Available Honey exhibits antimicrobial activities against a wide range of bacteria in different milieu. This study aims to compare the effects of five types of honey (both imported and local Saudi honey against Staphylococcus aureus. The five types of honey (Manuka Honey UMF +20, Manuka Honey UMF +16, Active +10 Manuka Honey, Sidr honey and Nigella sativa honey were evaluated for their bactericidal/bacteriostatic activities against both methicillin resistant and sensitive S. aureus. The inhibitory effect of honey on bacterial growth was evident at concentrations of 20% and 10% (v/v. Manuka Honey showed the best results. Manuka Honey UMF +20 had a bactericidal effect on both methicillin resistant and sensitive S. aureus. However, Sidr and N. sativa honey exerted only a bacteriostatic effect. The efficacy of different types of honey against S. aureus was dependent on the type of honey and the concentration at which it was administered. Manuka Honey had the best bactericidal activity. Future experiments should be conducted to evaluate the effects of honey on bacterial resistance.

  8. Dysbiosis and Staphylococcus aureus Colonization Drives Inflammation in Atopic Dermatitis.

    Science.gov (United States)

    Kobayashi, Tetsuro; Glatz, Martin; Horiuchi, Keisuke; Kawasaki, Hiroshi; Akiyama, Haruhiko; Kaplan, Daniel H; Kong, Heidi H; Amagai, Masayuki; Nagao, Keisuke

    2015-04-21

    Staphylococcus aureus skin colonization is universal in atopic dermatitis and common in cancer patients treated with epidermal growth factor receptor inhibitors. However, the causal relationship of dysbiosis and eczema has yet to be clarified. Herein, we demonstrate that Adam17(fl/fl)Sox9-(Cre) mice, generated to model ADAM17-deficiency in human, developed eczematous dermatitis with naturally occurring dysbiosis, similar to that observed in atopic dermatitis. Corynebacterium mastitidis, S. aureus, and Corynebacterium bovis sequentially emerged during the onset of eczematous dermatitis, and antibiotics specific for these bacterial species almost completely reversed dysbiosis and eliminated skin inflammation. Whereas S. aureus prominently drove eczema formation, C. bovis induced robust T helper 2 cell responses. Langerhans cells were required for eliciting immune responses against S. aureus inoculation. These results characterize differential contributions of dysbiotic flora during eczema formation, and highlight the microbiota-host immunity axis as a possible target for future therapeutics in eczematous dermatitis. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Staphylococcus aureus and Influenza A Virus: Partners in Coinfection

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    Michelle E. Mulcahy

    2016-12-01

    Full Text Available Nasal carriage of Staphylococcus aureus is a significant risk factor for secondary staphylococcal pneumonia in influenza A virus (IAV-infected hosts. However, little research has been undertaken to define the environmental and physiological changes that cause S. aureus to shift from commensal to pathogenic organism in this setting. The ability of virus-driven danger signals to cause S. aureus to transition from commensalism to pulmonary infection was explored in a recent study by Reddinger et al. R. M. Reddinger, N. R. Luke-Marshall, A. P. Hakansson, and A. A. Campagnari, mBio 7(6:e01235-16, 2016, http://dx.doi.org/10.1128/mBio.01235-16. The authors report that physiological host changes, including febrile temperature and a combination of host stress response signals, caused S. aureus biofilms to disperse from the nasal environment and cause active pulmonary infection. This commentary discusses the new finding in light of the current understanding of the mechanisms behind staphylococcal coinfection with IAV. In addition, it considers the mechanisms behind staphylococcal dispersal in this model. Overall, the study indicates that interkingdom signaling may occur following IAV infection and this likely contributes to sensitizing the IAV-infected host to secondary staphylococcal pneumonia.

  10. Expression of virulence factors by Staphylococcus aureus grown in serum.

    Science.gov (United States)

    Oogai, Yuichi; Matsuo, Miki; Hashimoto, Masahito; Kato, Fuminori; Sugai, Motoyuki; Komatsuzawa, Hitoshi

    2011-11-01

    Staphylococcus aureus produces many virulence factors, including toxins, immune-modulatory factors, and exoenzymes. Previous studies involving the analysis of virulence expression were mainly performed by in vitro experiments using bacterial medium. However, when S. aureus infects a host, the bacterial growth conditions are quite different from those in a medium, which may be related to the different expression of virulence factors in the host. In this study, we investigated the expression of virulence factors in S. aureus grown in calf serum. The expression of many virulence factors, including hemolysins, enterotoxins, proteases, and iron acquisition factors, was significantly increased compared with that in bacterial medium. In addition, the expression of RNA III, a global regulon for virulence expression, was significantly increased. This effect was partially restored by the addition of 300 μM FeCl₃ into serum, suggesting that iron depletion is associated with the increased expression of virulence factors in serum. In chemically defined medium without iron, a similar effect was observed. In a mutant with agr inactivated grown in serum, the expression of RNA III, psm, and sec4 was not increased, while other factors were still induced in the mutant, suggesting that another regulatory factor(s) is involved. In addition, we found that serum albumin is a major factor for the capture of free iron to prevent the supply of iron to bacteria grown in serum. These results indicate that S. aureus expresses virulence factors in adaptation to the host environment.

  11. Vaccine Protection of Leukopenic Mice against Staphylococcus aureus Bloodstream Infection

    Science.gov (United States)

    Rauch, Sabine; Gough, Portia; Kim, Hwan Keun; Schneewind, Olaf

    2014-01-01

    The risk for Staphylococcus aureus bloodstream infection (BSI) is increased in immunocompromised individuals, including patients with hematologic malignancy and/or chemotherapy. Due to the emergence of antibiotic-resistant strains, designated methicillin-resistant S. aureus (MRSA), staphylococcal BSI in cancer patients is associated with high mortality; however, neither a protective vaccine nor pathogen-specific immunotherapy is currently available. Here, we modeled staphylococcal BSI in leukopenic CD-1 mice that had been treated with cyclophosphamide, a drug for leukemia and lymphoma patients. Cyclophosphamide-treated mice were highly sensitive to S. aureus BSI and developed infectious lesions lacking immune cell infiltrates. Virulence factors of S. aureus that are key for disease establishment in immunocompetent hosts—α-hemolysin (Hla), iron-regulated surface determinants (IsdA and IsdB), coagulase (Coa), and von Willebrand factor binding protein (vWbp)—are dispensable for the pathogenesis of BSI in leukopenic mice. In contrast, sortase A mutants, which cannot assemble surface proteins, display delayed time to death and increased survival in this model. A vaccine with four surface antigens (ClfA, FnBPB, SdrD, and SpAKKAA), which was identified by genetic vaccinology using sortase A mutants, raised antigen-specific immune responses that protected leukopenic mice against staphylococcal BSI. PMID:25183728

  12. Staphylococcus aureus α toxin potentiates opportunistic bacterial lung infections.

    Science.gov (United States)

    Cohen, Taylor S; Hilliard, Jamese J; Jones-Nelson, Omari; Keller, Ashley E; O'Day, Terrence; Tkaczyk, Christine; DiGiandomenico, Antonio; Hamilton, Melissa; Pelletier, Mark; Wang, Qun; Diep, Binh An; Le, Vien T M; Cheng, Lily; Suzich, JoAnn; Stover, C Kendall; Sellman, Bret R

    2016-03-09

    Broad-spectrum antibiotic use may adversely affect a patient's beneficial microbiome and fuel cross-species spread of drug resistance. Although alternative pathogen-specific approaches are rationally justified, a major concern for this precision medicine strategy is that co-colonizing or co-infecting opportunistic bacteria may still cause serious disease. In a mixed-pathogen lung infection model, we find that the Staphylococcus aureus virulence factor α toxin potentiates Gram-negative bacterial proliferation, systemic spread, and lethality by preventing acidification of bacteria-containing macrophage phagosomes, thereby reducing effective killing of both S. aureus and Gram-negative bacteria. Prophylaxis or early treatment with a single α toxin neutralizing monoclonal antibody prevented proliferation of co-infecting Gram-negative pathogens and lethality while also promoting S. aureus clearance. These studies suggest that some pathogen-specific, antibody-based approaches may also work to reduce infection risk in patients colonized or co-infected with S. aureus and disparate drug-resistant Gram-negative bacterial opportunists. Copyright © 2016, American Association for the Advancement of Science.

  13. Effect of anticapsular antibodies on neutrophil phagocytosis of Staphylococcus aureus.

    Science.gov (United States)

    Guidry, A J; Oliver, S P; Squiggins, K E; Erbe, E F; Dowlen, H H; Hambleton, C N; Berning, L M

    1991-10-01

    One of the major virulence factors of Staphylococcus aureus is development of an exopolysaccharide capsule in vivo, which inhibits recognition of antibodies to highly antigenic cell wall by neutrophils. To circumvent this inhibition, an attempt was made to produce anticapsular antibodies. Three cows per group were immunized in midlactation by injections in the area of the supramammary lymph node and intramuscularly and were boosted on d 14, 42, and 70 with three variants of Smith S. aureus: compact, unencapsulated; diffuse, rigid capsule; and diffuse large clearing, exceptionally large flaccid capsule using dextran sulfate as adjuvant. Serum agglutination and ELISA titers of cows immunized with diffuse and diffuse large clearing increased after immunization and after each boost and remained elevated to the end of the experiment at 112 d. Phagocytosis of diffuse and diffuse large clearing, measured by flow cytometry, was enhanced by immunization with either organism. No antibody response to capsule or enhanced phagocytosis of diffuse developed in cows immunized with compact. However, anticompact antibodies were opsonic for diffuse large clearing. These data show that bovine antibodies to S. aureus capsule are opsonic for bovine neutrophils and that capsule plays a role in inhibition of cell-wall opsonization of S. aureus.

  14. Metabolic Stress Drives Keratinocyte Defenses against Staphylococcus aureus Infection

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    Matthew Wickersham

    2017-03-01

    Full Text Available Human skin is commonly colonized and infected by Staphylococcus aureus. Exactly how these organisms are sensed by keratinocytes has not been clearly delineated. Using a combination of metabolic and transcriptomic methodologies, we found that S. aureus infection is sensed as a metabolic stress by the hypoxic keratinocytes. This induces HIF1α signaling, which promotes IL-1β production and stimulates aerobic glycolysis to meet the metabolic requirements of infection. We demonstrate that staphylococci capable of glycolysis, including WT and agr mutants, readily induce HIF1α responses. In contrast, Δpyk glycolytic mutants fail to compete with keratinocytes for their metabolic needs. Suppression of glycolysis using 2-DG blocked keratinocyte production of IL-1β in vitro and significantly exacerbated the S. aureus cutaneous infection in a murine model. Our data suggest that S. aureus impose a metabolic stress on keratinocytes that initiates signaling necessary to promote both glycolysis and the proinflammatory response to infection.

  15. Predictive characterization of hypothetical proteins in Staphylococcus aureus NCTC 8325.

    Science.gov (United States)

    School, Kuana; Marklevitz, Jessica; K Schram, William; K Harris, Laura

    2016-01-01

    Staphylococcus aureus is one of the most common hospital acquired infections. It colonizes immunocompromised patients and with the number of antibiotic resistant strains increasing, medicine needs new treatment options. Understanding more about the proteins this organism uses would further this goal. Hypothetical proteins are sequences thought to encode a functional protein but for which little to no evidence of that function exists. About half of the genomic proteins in reference strain S. aureus NCTC 8325 are hypothetical. Since annotation of these proteins can lead to new therapeutic targets, a high demand to characterize hypothetical proteins is present. This work examines 35 hypothetical proteins from the chromosome of S. aureus NCTC 8325. Examination includes physiochemical characterization; sequence homology; structural homology; domain recognition; structure modeling; active site depiction; predicted protein-protein interactions; protein-chemical interactions; protein localization; protein stability; and protein solubility. The examination revealed some hypothetical proteins related to virulent domains and protein-protein interactions including superoxide dismutase, O-antigen, bacterial ferric iron reductase and siderophore synthesis. Yet other hypothetical proteins appear to be metabolic or transport proteins including ABC transporters, major facilitator superfamily, S-adenosylmethionine decarboxylase, and GTPases. Progress evaluating some hypothetical proteins, particularly the smaller ones, was incomplete due to limited homology and structural information in public repositories. These data characterizing hypothetical proteins will contribute to the scientific understanding of S. aureus by identifying potential drug targets and aiding in future drug discovery.

  16. Human Staphylococcus aureus lineages among Zoological Park residents in Greece

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    E. Drougka

    2015-10-01

    Full Text Available Staphylococcus aureus is a part of the microbiota flora in many animal species. The clonal spread of S. aureus among animals and personnel in a Zoological Park was investigated. Samples were collected from colonized and infected sites among 32 mammals, 11 birds and eight humans. The genes mecA, mecC, lukF/lukS-PV (encoding Panton-Valentine leukocidin, PVL and tst (toxic shock syndrome toxin-1 were investigated by PCR. Clones were defined by Multilocus Sequence Typing (MLST, spa type and Pulsed-Field Gel Electrophoresis (PFGE. Seven S. aureus isolates were recovered from four animals and one from an employee. All were mecA, mecC and tst–negative, whereas, one carried the PVL genes and was isolated from an infected Squirrel monkey. Clonal analysis revealed the occurrence of seven STs, eight PFGE and five spa types including ones of human origin. Even though a variety of genotypes were identified among S. aureus strains colonizing zoo park residents, our results indicate that colonization with human lineages has indeed occurred.

  17. Antibacterial activity of alimentary plants against Staphylococcus aureus growth.

    Science.gov (United States)

    Pérez, C; Anesini, C

    1994-01-01

    Alimentary plants were screened for antibacterial activity against a penicillin G resistant strain of Staphylococcus aureus. Twenty-five samples of plant material corresponding to 21 species from 13 families were used. Both aqueous and ethanol extracts were obtained from them. Antibacterial activity was determined by the agar-well diffusion method, using cephazolin as a standard antibiotic. Seventeen ethanol extracts were found active. Eugenia caryophyllata (clavo de olor*) flowers, Myristica fragans (nuez moscada*) seeds, Theobroma cacao (cacao*) seed bark, Triticum sp (trigo*) fruit, Zea mays (maíz*) fruit and Piper nigrum (pimienta*) ripe fruit produced some of the more active extracts (* = Argentine vulgar names).

  18. Radiation induced changes in alpha toxin of Staphylococcus aureus 3750

    Energy Technology Data Exchange (ETDEWEB)

    Sherekar, S.V.; Bhushan, B.; Gore, M.S. (Bhabha Atomic Research Centre, Bombay (India). Biochemistry and Food Technology Div.)

    1981-06-01

    Influence of ..gamma..-radiation and heat on haemolytic activity of purified alpha toxin from staphylococcus aureus 3750 cells was studied. Heat treatment at 60deg C for 1 min resulted in 99% inactivation of alpha toxin, while exposure to ..gamma..-radiation caused linear decline in activity, 40 krad causing 50% inactivation. Urea treatment reversed the heat induced inactivation but did not reactivate the irradiated toxin. However, the irradiated toxin retained its antigenicity, thus indicating its potential for the preparation of toxoid against alpha toxin.

  19. Molecular mechanisms of methicillin resistance in Staphylococcus aureus.

    Science.gov (United States)

    Domínguez, M A; Liñares, J; Martín, R

    1997-09-01

    Methicillin-resistant Staphylococcus aureus (MRSA) strains are among the most common nosocomial pathogens. The most significant mechanism of resistance to methicillin in this-species is the acquisition of a genetic determinant (mecA gene). However, resistance seems to have a more complex molecular basis, since additional chromosomal material is involved in such resistance. Besides, overproduction of penicillinase and/or alterations in the PBPs can contribute to the formation of resistance phenotypes. Genetic and environmental factors leading to MRSA are reviewed.

  20. Drugs resistance and penicillinase activity in skin isolated Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Gopalkrishna Bhat

    1990-01-01

    Full Text Available A study was carried out to evaluate the drug resistance pattern and penicillinase production in skin isolated Staphylococcus aurpus. The disk diffusion method showed prevalence of: multidrug resistance among S. aureus, strains, isolated from locafised skin abscesses. method for detection of penicilfinase could detect this enzyme m 98.60/o of the isolates all fo which were resistant to penicillin and ampicillin. C16xacillin resistance as detected by the agar dilution method was found in 1.4% of the isolates. On the whole cloxacillin and gentamy′cin were found to be the most effective ′antistaphylococcal antibotics.

  1. Methicillin-resistant Staphylococcus aureus in North-east Croatia

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    Tajana Pastuović

    2015-05-01

    Full Text Available Objective. The aim of this 5-year study was to determine the frequency and antibiotic susceptibility of methicillin-resistant Staphylococcus aureus (MRSA-related infections at Osijek Clinical Hospital. Materials and methods. A total of 1987 staphylococci-infected clinical isolates were collected and analysed at the Microbiology Department of the Public Health Institute of Osijek-Baranja County. Results. Between 2008 and 2012, the average rate of MRSA-related infections in staphylococci-infected patients was 27.4%. The proportion of MRSArelated infections on all Staphylococcus aureus (S. aureus isolates from clinical specimens showed a decreasing trend, from 32.6% in 2008 to 25.5% in 2012. MRSA-related infections were mostly detected in wound swabs (50.6% and aspirates (28.8% of patients hospitalized in the surgical (49.8% and intensive care units (27.9%. MRSA-related infection showed an increase compared to S. aureus-infections in samples of wounds and aspirates in 2011 and 2012 (57.9%/34.9% and 35.2%/16.3%, respectively. The majority of strains of MRSA-related infections were resistant to several antibiotics, including erythromycin and clindamycin, where susceptibility were less than 10%. All MRSA isolates were susceptible to vancomycin, teicoplanin and linezolid. Therefore, antibiotic therapies for MRSA infections include vancomycin, teicoplanin and linezolid, but microbiological diagnostics need to be performed in order to know when the use of glycopeptides and oxazolidinones is indicated. Conclusion. Our results suggest that appropriate prevention measures, combined with the more rational use of antibiotics are crucial to reduce the spread of MRSA-related infection in healthcare settings. Further monitoring is necessary of the incidence and antibiotic susceptibility of MRSA-related infections in our community.

  2. Genome-Wide Analysis of Ruminant Staphylococcus aureus Reveals Diversification of the Core Genome▿ †

    OpenAIRE

    Ben Zakour, Nouri L; Sturdevant, Daniel E.; Even, Sergine; Guinane, Caitriona M.; Barbey, Corinne; Alves, Priscila D.; Cochet, Marie-Françoise; Gautier, Michel; Otto, Michael; Fitzgerald, J. Ross; Le Loir, Yves

    2008-01-01

    Staphylococcus aureus causes disease in humans and a wide array of animals. Of note, S. aureus mastitis of ruminants, including cows, sheep, and goats, results in major economic losses worldwide. Extensive variation in genome content exists among S. aureus pathogenic clones. However, the genomic variation among S. aureus strains infecting different animal species has not been well examined. To investigate variation in the genome content of human and ruminant S. aureus, we carried out whole-ge...

  3. Daptomycin-Nonsusceptible, Vancomycin-Intermediate, Methicillin-Resistant Staphylococcus aureus Endocarditis

    Directory of Open Access Journals (Sweden)

    Ryan Yu

    2012-01-01

    Full Text Available Due to the emergence of Staphylococcus aureus with reduced vancomycin susceptibility, newer antibiotics, including daptomycin, have been used to treat methicillin-resistant S aureus infections. Daptomycin is a cyclic lipopeptide that is approved to treat S aureus bacteremia and right-sided endocarditis, and reports of S aureus with reduced susceptibility to daptomycin are infrequent. To our knowledge, the present report describes the first Canadian case of daptomycin-nonsusceptible, vancomycin-intermediate S aureus infection.

  4. Staphylococcus aureus complex from animals and humans in three remote African regions

    NARCIS (Netherlands)

    F. Schaumburg (Frieder); M. Pauly (Maude); E. Anoh (Etile); A. Mossoun (Arsène); L.C.M. Wiersma (Lidewij); G. Schubert (Grit); A. Flammen (Arnaud); A.S. Alabi (Abraham S.); J.-J. Muyembe-Tamfum (Jean-Jacques); M.P. Grobusch (Martin P.); S. Karhemere (Stomy); C. Akoua-Koffi (Chantal); E. Couacy-Hymann (Emmanuel); P.G. Kremsner (Peter); A. Mellmann (Alexander); K. Becker (Karsten); F.H. Leendertz (Fabian); G. Peters (Georg)

    2015-01-01

    textabstractStaphylococcus schweitzeri has been recently considered to be a highly divergent Staphylococcus aureus clade and usually colonises nonhuman primates and bats in sub-Saharan Africa. Its transmissibility to humans remains unclear. We therefore investigated the transmission of S.aureus and

  5. Anti-Methicillin Resistant Staphylococcus aureus Activity and Optimal Culture Condition of Streptomyces sp. SUK 25

    OpenAIRE

    Siti Junaidah, Ahmad; Suhaini, Sudi; Mohd Sidek, Hasidah; Basri, Dayang Fredalina; Zin,Noraziah Mohamad

    2015-01-01

    Background: The potential of secondary metabolites extracted from Streptomyces sp. to treat bacterial infections including infections with Staphylococcus aureus is previously documented. The current study showed significant antimicrobial activities associated with endophytic Streptomyces sp. isolated from medicinal plants in Peninsular Malaysia. Objectives: The current study aimed to determine anti-methicillin-resistant-Staphylococcus aureus (MRSA) activities of Streptomyces sp. isolates. Mat...

  6. Staphylococcus aureus complex from animals and humans in three remote African regions

    NARCIS (Netherlands)

    Schaumburg, Frieder; Pauly, Maude; Anoh, Etile; Mossoun, Arsene; Wiersma, Lidewij; Schubert, Grit; Flammen, Arnaud; Alabi, Abraham S.; Muyembe-Tamfum, Jean-Jacques; Grobusch, Martin P.; Karhemere, Stomy; Akoua-Koffi, Chantal; Couacy-Hymann, Emmanuel; Kremsner, Peter G.; Mellmann, Alexander; Becker, Karsten; Leendertz, Fabian H.; Peters, Georg

    2015-01-01

    Staphylococcus schweitzeri has been recently considered to be a highly divergent Staphylococcus aureus clade and usually colonises nonhuman primates and bats in sub-Saharan Africa. Its transmissibility to humans remains unclear. We therefore investigated the transmission of S. aureus and S.

  7. Characterization of Staphylococcus aureus Strains Associated with Food Poisoning in Shenzhen, China

    NARCIS (Netherlands)

    Yan, Xiaomei; Wang, Bing; Tao, Xiaoxia; Hu, Qinghua; Cui, Zhigang; Zhang, Jianzhong; Lin, Yiman; You, Yuanhai; Shi, Xiaolu; Grundmann, Hajo

    To characterize isolates of Staphylococcus aureus that were associated with staphylococcal food poisoning between 2006 and 2009 in Shenzhen, Southern China, a total of 52 Staphylococcus aureus isolates from 11 outbreaks were analyzed by using multilocus sequence typing (MLST), spa typing, and

  8. Development of the immune response in pneumonia due to Staphylococcus aureus (part 4

    Directory of Open Access Journals (Sweden)

    A.E. Abaturov

    2017-08-01

    Full Text Available In this article, based on the literature sources, the key role of chemokines of CC, CXS families and antimicrobial peptides in the elimination of Staphylococcus aureus is analyzed. The main mechanisms of the anti-staphylococcal activity of catelicidin LL-37 in the development of the immune response in pneumonia caused by Staphylococcus aureus are described in detail.

  9. Concurrent infectious mononucleosis and community-associated methicillin-resistant Staphylococcus aureus bacteremia.

    Science.gov (United States)

    Wang, Li Jun; Du, Xiao Qin; Nyirimigabo, Eric; Shou, Song Tao

    2014-04-01

    It is rare to see a concurrent infection with infectious mononucleosis and community-associated methicillin-resistant Staphylococcus aureus in Tianjin, China. Until now, there is still no any single recorded case of concurrent infectious mononucleosis and community-associated methicillin-resistant Staphylococcus aureus bacteremia.

  10. Staphylococcus aureus and Staphylococcus epidermidis Virulence Strains as Causative Agents of Persistent Infections in Breast Implants.

    Directory of Open Access Journals (Sweden)

    Daniela Chessa

    Full Text Available Staphylococcus epidermidis and Staphylococcus aureus are currently considered two of the most important pathogens in nosocomial infections associated with catheters and other medical implants and are also the main contaminants of medical instruments. However because these species of Staphylococcus are part of the normal bacterial flora of human skin and mucosal surfaces, it is difficult to discern when a microbial isolate is the cause of infection or is detected on samples as a consequence of contamination. Rapid identification of invasive strains of Staphylococcus infections is crucial for correctly diagnosing and treating infections. The aim of the present study was to identify specific genes to distinguish between invasive and contaminating S. epidermidis and S. aureus strains isolated on medical devices; the majority of our samples were collected from breast prostheses. As a first step, we compared the adhesion ability of these samples with their efficacy in forming biofilms; second, we explored whether it is possible to determine if isolated pathogens were more virulent compared with international controls. In addition, this work may provide additional information on these pathogens, which are traditionally considered harmful bacteria in humans, and may increase our knowledge of virulence factors for these types of infections.

  11. Staphylococcus aureus and Community-Associated Methicillin-Resistant Staphylococcus aureus (CA-MRSA) in and Around Therapeutic Whirlpools in College Athletic Training Rooms

    Science.gov (United States)

    Kahanov, Leamor; Kim, Young Kyun; Eberman, Lindsey; Dannelly, Kathleen; Kaur, Haninder; Ramalinga, A.

    2015-01-01

    Context: Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has become a leading cause of skin and soft tissue infection in the nonhospitalized community. Care of the athletes in athletic training rooms is specifically designed with equipment tailored to the health care needs of the athletes, yet recent studies indicate that CA-MRSA is still prevalent in athletic facilities and that cleaning methods may not be optimal. Objective: To investigate the prevalence of Staphylococcus aureus and CA-MRSA in and around whirlpools in the athletic training room. Design: Cross-sectional study. Setting: National Collegiate Athletic Association Division I university. Patients or Other Participants: Student-athletes (n = 109) consisting of 46 men (42%) and 63 women (58%) representing 6 sports. Main Outcome Measure(s): Presence of MRSA and Staphylococcus aureus in and around the whirlpool structures relative to sport and number of athletes using the whirlpools. Results: We identified Staphylococcus aureus in 22% (n = 52/240) of the samples and MRSA in 0.8% (n = 2/240). A statistically significant difference existed between the number of athletes using the whirlpool and the presence of Staphylococcus aureus in and around the whirlpools (F2,238 = 2.445, P = .007). However, Staphylococcus aureus was identified regardless of whether multiple athletes used a whirlpool or no athletes used a whirlpool. We did not identify a relationship between the number of athletes who used a whirlpool and Staphylococcus aureus or MRSA density (P = .134). Conclusions: Staphylococcus aureus and MRSA were identified in and around the whirlpools. Transmission of the bacteria can be reduced by following the cleaning and disinfecting protocols recommended by the Centers for Disease Control and Prevention. Athletic trainers should use disinfectants registered by the Environmental Protection Agency to sanitize all whirlpools between uses. PMID:25710853

  12. Staphylococcus aureus and community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) in and around therapeutic whirlpools in college athletic training rooms.

    Science.gov (United States)

    Kahanov, Leamor; Kim, Young Kyun; Eberman, Lindsey; Dannelly, Kathleen; Kaur, Haninder; Ramalinga, A

    2015-04-01

    Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has become a leading cause of skin and soft tissue infection in the nonhospitalized community. Care of the athletes in athletic training rooms is specifically designed with equipment tailored to the health care needs of the athletes, yet recent studies indicate that CA-MRSA is still prevalent in athletic facilities and that cleaning methods may not be optimal. To investigate the prevalence of Staphylococcus aureus and CA-MRSA in and around whirlpools in the athletic training room. Cross-sectional study. National Collegiate Athletic Association Division I university. Student-athletes (n = 109) consisting of 46 men (42%) and 63 women (58%) representing 6 sports. Presence of MRSA and Staphylococcus aureus in and around the whirlpool structures relative to sport and number of athletes using the whirlpools. We identified Staphylococcus aureus in 22% (n = 52/240) of the samples and MRSA in 0.8% (n = 2/240). A statistically significant difference existed between the number of athletes using the whirlpool and the presence of Staphylococcus aureus in and around the whirlpools (F(2,238) = 2.445, P = .007). However, Staphylococcus aureus was identified regardless of whether multiple athletes used a whirlpool or no athletes used a whirlpool. We did not identify a relationship between the number of athletes who used a whirlpool and Staphylococcus aureus or MRSA density (P = .134). Staphylococcus aureus and MRSA were identified in and around the whirlpools. Transmission of the bacteria can be reduced by following the cleaning and disinfecting protocols recommended by the Centers for Disease Control and Prevention. Athletic trainers should use disinfectants registered by the Environmental Protection Agency to sanitize all whirlpools between uses.

  13. [Detection of Staphylococcus aureus, Shigella spp., Salmonella spp. in food by multiplex PCR].

    Science.gov (United States)

    Li, Bo; Chen, Fusheng; Wang, Xiaohong; Shao, Yanchun

    2008-07-01

    To establish a multiplex PCR method for simultaneous detection of Staphylococcus aureus, Shigella spp., Salmonella spp. in food. Staphylococcus aureus was enriched by 7.5% NaCl broth while Shigella spp. and Salmonella spp. were enriched by GN medium . The primers were designed according to the gene nuc of Staphylococcus aureus, the gene ipaH of Shigella spp. and the gene invA of Salmonella spp. The target genes of these pathogens in food were amplified by multiplex PCR, which reaction conditions were optimized specifically. The multiplex PCR method established in this experment was of high specificity, which detection limit was 1 cfu/ml of Staphylococcus aureus, Shigella spp. and Salmonella spp. when the milk samples contaminated with these pathogens. The multiplex PCR method, which was rapid, convenient, and with high sensitivity, could be suitable for rapid detection of Staphylococcus aureus, Shigella spp., Salmonella spp. in food, and could have a great prospect.

  14. Response of Staphylococcus Aureus to a Spaceflight Analogue

    Science.gov (United States)

    Castro, S. L.; Ott, C. M.

    2010-01-01

    The decreased gravity of the spaceflight environment creates quiescent, low fluid shear conditions. This environment can impart considerable effects on the physiology of microorganisms as well as their interactions with potential hosts. Using the rotating wall vessel (RWV), as a spaceflight analogue, the consequence of low fluid shear culture on microbial pathogenesis has provided a better understanding of the risks to the astronaut crew from infectious microorganisms. While the outcome of low fluid shear culture has been investigated for several bacterial pathogens, little has been done to understand how this environmental factor affects Staphylococcus aureus. S. aureus is an opportunistic human pathogen which presents a high level of infection risk to the crew, as it has been isolated from both the space shuttle and International Space Station. Given that approximately forty percent of the population are carriers of the bacteria, eradication of this organism from in flight environments is impractical. These reasons have lead to us to assess the response of S. aureus to a reduced fluid shear environment. Culture in the RWV demonstrated that S. aureus grown under the low-shear condition had lower cell concentrations after 10 hours when compared to the control culture. Furthermore, the low-shear cultured bacteria displayed a reduction in carotenoid production, pigments responsible for their yellow/gold coloration. When exposed to various environmental stressors, post low-shear culture, a decrease in the ability to survive oxidative assault was observed compared to control cultures. The low fluid shear environment also resulted in a decrease in hemolysin secretion, a staphylococcal toxin responsible for red blood cell lysis. When challenged by the immune components present in human whole blood, low-shear cultured S. aureus demonstrated significantly reduced survival rates as compared to the control culture. Assays to determine the duration of these alterations

  15. Evaluation of the Rapid Mastitis Test for identification of Staphylococcus aureus and Streptococcus agalactiae isolated from bovine mammary glands.

    OpenAIRE

    Watts, J L; Owens, W E

    1988-01-01

    A latex agglutination test system (Rapid Mastitis Test [RMT]; Immucell, Portland, Maine) containing reagents for the identification of Staphylococcus aureus and Streptococcus agalactiae from bovine intramammary infections was evaluated with 527 staphylococcal and 267 streptococcal isolates. The RMT Staphylococcus aureus reagent detected 94.2% of 242 Staphylococcus aureus isolates, 80% of 25 Staphylococcus intermedius isolates, and 42.8% of 21 tube coagulase-positive Staphylococcus hyicus isol...

  16. Comparison of the BBL CHROMagar Staph aureus agar medium to conventional media for detection of Staphylococcus aureus in respiratory samples.

    Science.gov (United States)

    Flayhart, Diane; Lema, Clara; Borek, Anita; Carroll, Karen C

    2004-08-01

    Screening for Staphylococcus aureus has become routine in certain patient populations. This study is the first clinical evaluation of the BBL CHROMagar Staph aureus agar (CSA) medium (BD Diagnostics, Sparks, Md.) for detection of S. aureus in nasal surveillance cultures and in respiratory samples from cystic fibrosis (CF) patients. S. aureus colonies appear mauve on CSA. Other organisms are inhibited or produce a distinctly different colony color. S. aureus was identified from all media by slide coagulase, exogenous DNase, and mannitol fermentation assays. Susceptibility testing was performed using the agar dilution method. A total of 679 samples were evaluated. All samples were inoculated onto CSA. Nasal surveillance cultures were inoculated onto sheep blood agar (SBA) (BD Diagnostics), and samples from CF patients were inoculated onto mannitol salt agar (MSA) (BD Diagnostics). Of the 679 samples cultured, 200 organisms produced a mauve color on CSA (suspicious for S. aureus) and 180 were positive for S. aureus on SBA or MSA. Of 200 CSA-positive samples 191 were identified as S. aureus. Nine mauve colonies were slide coagulase negative and were subsequently identified as Staphylococcus lugdunensis (one), Staphylococcus epidermidis (three), Staphylococcus haemolyticus (one), and Corynebacterium species (four). CSA improved the ability to detect S. aureus by recovering 12 S. aureus isolates missed by conventional media. Of the 192 S. aureus isolates recovered, 122 were methicillin susceptible and 70 were methicillin resistant. Overall, the sensitivity and specificity of CSA in this study were 99.5 and 98%, respectively. There was no difference in the performance of the slide coagulase test or in susceptibility testing performed on S. aureus recovered from CSA compared to SBA or MSA. Our data support the use of CSA in place of standard culture media for detection of S. aureus in heavily contaminated respiratory samples.

  17. Molecular Characterization of Staphylococcus aureus Isolated from Bovine Mastitis and Close Human Contacts in South African Dairy Herds: Genetic Diversity and Inter-Species Host Transmission

    Science.gov (United States)

    Schmidt, Tracy; Kock, Marleen M.; Ehlers, Marthie M.

    2017-01-01

    Staphylococcus aureus is one of the most common etiological agents of contagious bovine mastitis worldwide. The purpose of this study was to genetically characterize a collection of S. aureus isolates (bovine = 146, human = 12) recovered from cases of bovine mastitis and nasal swabs of close human contacts in the dairy environment. Isolates were screened for a combination of clinically significant antimicrobial and virulence gene markers whilst the molecular epidemiology of these isolates and possible inter-species host transmission was investigated using a combination of genotyping techniques. None of the isolates under evaluation tested positive for methicillin or vancomycin resistance encoding genes. Twenty seven percent of the bovine S. aureus isolates tested positive for one or more of the pyrogenic toxin superantigen (PTSAg) genes with the sec and sell genes predominating. Comparatively, 83% of the human S. aureus isolates tested positive for one or more PTSAg genes with a greater variety of genes being detected. Genomic DNA macrorestriction followed by pulsed-field gel electrophoresis (PFGE) of the bovine isolates generated 58 electrophoretic patterns which grouped into 10 pulsotypes at an 80% similarity level. The majority of the bovine isolates, 93.2% (136/146), clustered into four major pulsotypes. Seven sequence types (ST) were identified among the representative bovine S. aureus isolates genotyped, including: ST8 (CC8), ST97 (CC97), ST351 (CC705), ST352 (CC97), ST508 (CC45), ST2992 (CC97) and a novel sequence type, ST3538 (CC97). Based on PFGE analysis, greater genetic diversity was observed among the human S. aureus isolates. Bovine and human isolates from three sampling sites clustered together and were genotypically indistinguishable. Two of the isolates, ST97 and ST352 belong to the common bovine lineage CC97, and their isolation from close human contacts suggests zoonotic transfer. In the context of this study, the third isolate, ST8 (CC8), is

  18. Type I signal peptidase and protein secretion in Staphylococcus aureus.

    Science.gov (United States)

    Schallenberger, Mark A; Niessen, Sherry; Shao, Changxia; Fowler, Bruce J; Romesberg, Floyd E

    2012-05-01

    Staphylococcus aureus is an important human pathogen whose virulence relies on the secretion of many different proteins. In general, the secretion of most proteins in S. aureus, as well as other bacteria, is dependent on the type I signal peptidase (SPase)-mediated cleavage of the N-terminal signal peptide that targets a protein to the general secretory pathway. The arylomycins are a class of natural product antibiotics that inhibit SPase, suggesting that they may be useful chemical biology tools for characterizing the secretome. While wild-type S. aureus (NCTC 8325) is naturally resistant to the arylomycins, sensitivity is conferred via a point mutation in its SPase. Here, we use a synthetic arylomycin along with a sensitized strain of S. aureus and multidimensional protein identification technology (MudPIT) mass spectrometry to identify 46 proteins whose extracellular accumulation requires SPase activity. Forty-four possess identifiable Sec-type signal peptides and thus are likely canonically secreted proteins, while four also appear to possess cell wall retention signals. We also identified the soluble C-terminal domains of two transmembrane proteins, lipoteichoic acid synthase, LtaS, and O-acyteltransferase, OatA, both of which appear to have noncanonical, internal SPase cleavage sites. Lastly, we identified three proteins, HtrA, PrsA, and SAOUHSC_01761, whose secretion is induced by arylomycin treatment. In addition to elucidating fundamental aspects of the physiology and pathology of S. aureus, the data suggest that an arylomycin-based therapeutic would reduce virulence while simultaneously eradicating an infection.

  19. Staphylococcus aureus Keratitis: A Review of Hospital Cases

    Science.gov (United States)

    Ong, Sherine Jue; Huang, Yhu-Chering; Tan, Hsin-Yuan; Ma, David H. K.; Lin, Hsin-Chiung; Yeh, Lung-Kun; Chen, Phil Y. F.; Chen, Hung-Chi; Chuang, Chih-Chun; Chang, Chee-Jen; Hsiao, Ching-Hsi

    2013-01-01

    Background Methicillin-resistant Staphylococcus aureus (MRSA) infection is an important public health issue. The study aimed to characterize the patient demographics, clinical features, antibiotic susceptibility, and clinical outcomes of keratitis caused by S. aureus, and to make a comparison between MRSA and methicillin-sensitive S. aureus (MSSA) isolates. Methodology/Principal findings Patients (n = 59) with culture-proven S. aureus keratitis treated in Chang Gung Memorial Hospital between January 1, 2006, and December 31, 2010, were included in our study. Patients' demographic and clinical data were retrospectively reviewed. Twenty-six MRSA (44%) and 33 MSSA (56%) isolates were collected. The MRSA keratitis was significantly more common among the patients with healthcare exposure (P = 0.038), but 46.2% (12/26) of patients with MRSA keratitis were considered to have community-associated infections. All isolates were susceptible to vancomycin. MRSA isolates were significantly more resistant to clindamycin, erythromycin, and sulfamethoxazole/trimethoprim. Ocular surface disease was a significant risk factor for MRSA keratitis (P = 0.011). Visual outcome did not differ significantly between the MRSA and MSSA groups. However, age (B = 0.01, P = 0.035, 95% confidence interval [CI]: 0.001–0.019) and visual acuity at presentation (B = 0.749, Pkeratitis, especially for MRSA infections. Advanced age and poor visual acuity at presentation are important prognostic indicators for poor visual outcome in S. aureus keratitis. Oxacillin resistance may not be a significant prognostic indicator. PMID:24244625

  20. Intracellular Staphylococcus aureus: the Trojan horse of recalcitrant chronic rhinosinusitis?

    Science.gov (United States)

    Tan, Neil C-W; Foreman, Andrew; Jardeleza, Camille; Douglas, Richard; Vreugde, Sarah; Wormald, Peter-John

    2013-04-01

    Despite recent evidence suggesting that Staphylococcus aureus exists within the sinonasal epithelium of chronic rhinosinusitis (CRS) patients, certain questions remain. The intracellular environment may provide a protective niche for pathogenic bacteria to evade host immunity and yet provide a reservoir for reinfection. To date, no studies have examined the impact of this bacterial phenotype; therefore, this study was designed to evaluate the role of intracellular S. aureus on postsurgical outcomes. This study included 51 patients undergoing endoscopic sinus surgery (ESS) for medically-recalcitrant CRS. Sinonasal mucosa harvested at the time of surgery was dually stained with fluorescent molecular probes and imaged using confocal scanning laser microscopy for biofilm and intracellular status. Patients were followed in their early and late postoperative course for evidence of ongoing disease and signs of clinical relapse. Intracellular S. aureus was identified in 20 of 51 (39%) patients, and all were associated with surface biofilm. Biofilm alone was found in 16 of 51 (31%) patients and 15 of 51 (29%) patients had no evidence of S. aureus. Intracellular positive patients had a significantly higher risk of late clinical and microbiological relapse (p = 0.014). In this study, biofilm status without coexisting intracellular bacteria did not appear to impact on outcomes. Clinical and microbiological relapse of disease following ESS is significantly associated with intracellular S. aureus. Evidence suggests that this disease association is independent to surface biofilm status. Intracellular bacteria should be taken into consideration when designing novel treatment strategies to lessen the chance of reinfection. © 2013 ARS-AAOA, LLC.

  1. Characterization of a mouse-adapted Staphylococcus aureus strain.

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    Silva Holtfreter

    Full Text Available More effective antibiotics and a protective vaccine are desperately needed to combat the 'superbug' Staphylococcus aureus. While in vivo pathogenicity studies routinely involve infection of mice with human S. aureus isolates, recent genetic studies have demonstrated that S. aureus lineages are largely host-specific. The use of such animal-adapted S. aureus strains may therefore be a promising approach for developing more clinically relevant animal infection models. We have isolated a mouse-adapted S. aureus strain (JSNZ which caused a severe outbreak of preputial gland abscesses among male C57BL/6J mice. We aimed to extensively characterize this strain on a genomic level and determine its virulence potential in murine colonization and infection models. JSNZ belongs to the MLST type ST88, rare among human isolates, and lacks an hlb-converting phage encoding human-specific immune evasion factors. Naive mice were found to be more susceptible to nasal and gastrointestinal colonization with JSNZ than with the human-derived Newman strain. Furthermore, naïve mice required antibiotic pre-treatment to become colonized with Newman. In contrast, JSNZ was able to colonize mice in the absence of antibiotic treatment suggesting that this strain can compete with the natural flora for space and nutrients. In a renal abscess model, JSNZ caused more severe disease than Newman with greater weight loss and bacterial burden. In contrast to most other clinical isolates, JSNZ can also be readily genetically modified by phage transduction and electroporation. In conclusion, the mouse-adapted strain JSNZ may represent a valuable tool for studying aspects of mucosal colonization and for screening novel vaccines and therapies directed at preventing colonization.

  2. Heme Recognition By a Staphylococcus Aureus IsdE

    Energy Technology Data Exchange (ETDEWEB)

    Grigg, J.C.; Vermeiren, C.L.; Heinrichs, D.E.; Murphy, M.E.P.

    2009-06-03

    Staphylococcus aureus is a Gram-positive bacterial pathogen and a leading cause of hospital acquired infections. Because the free iron concentration in the human body is too low to support growth, S. aureus must acquire iron from host sources. Heme iron is the most prevalent iron reservoir in the human body and a predominant source of iron for S. aureus. The iron-regulated surface determinant (Isd) system removes heme from host heme proteins and transfers it to IsdE, the cognate substrate-binding lipoprotein of an ATP-binding cassette transporter, for import and subsequent degradation. Herein, we report the crystal structure of the soluble portion of the IsdE lipoprotein in complex with heme. The structure reveals a bi-lobed topology formed by an N- and C-terminal domain bridged by a single {alpha}-helix. The structure places IsdE as a member of the helical backbone metal receptor superfamily. A six-coordinate heme molecule is bound in the groove established at the domain interface, and the heme iron is coordinated in a novel fashion for heme transporters by Met{sup 78} and His{sup 229}. Both heme propionate groups are secured by H-bonds to IsdE main chain and side chain groups. Of these residues, His{sup 299} is essential for IsdE-mediated heme uptake by S. aureus when growth on heme as a sole iron source is measured. Multiple sequence alignments of homologues from several other Gram-positive bacteria, including the human pathogens pyogenes, Bacillus anthracis, and Listeria monocytogenes, suggest that these other systems function equivalently to S. aureus IsdE with respect to heme binding and transport.

  3. Food Microorganisms Influencing the Growth of Staphylococcus aureus1

    Science.gov (United States)

    Graves, R. R.; Frazier, W. C.

    1963-01-01

    Some 870 cultures of predominating micro-organisms were isolated from market samples of hamburger, fresh pork sausage, fresh fish fillets, stewing beef, frozen chicken pot pie, frozen corn, frozen peas, and pasteurized and raw milk, before and after storage at different temperatures. The isolates were screened for their ability to influence the growth of Staphylococcus aureus strain 196E by means of spot-plate tests on APT and nutrient agars at 25 C. The 438 cultures that influenced the growth of S. aureus were retested on spot plates at 15, 30, and 42 C. After elimination of replicates, the 143 remaining cultures were classified into species, genera, or groups, and 14 different cultures were tested for their influence on the growth of S. aureus in APT broth at 25 C. Over half of the effective cultures inhibited S. aureus and less than half were stimulatory. Pork sausage had the highest proportion of inhibitory cultures, and stewing beef had the lowest. APT agar was better than nutrient agar for screening, and incubation at 15 C gave more effector organisms than at 30 and 42 C. Most of the lactic acid bacteria were inhibitory, but other groups of bacteria contained more stimulatory cultures than inhibitory ones. The three Escherichia coli cultures were stimulatory, but most other Escherichia cultures were inhibitory. Aerobacter and Paracolobactrum isolates were mostly stimulatory. Cultures of other kinds of bacteria were more or less evenly distributed between inhibitory ones and stimulatory ones. Genera containing mostly inhibitory bacteria were Streptococcus, Leuconostoc, and Lactobacillus. Inhibitory species were E. freundii and E. intermedia. Tests with S. aureus in broth indicated that all cultures inhibitory according to spot plates were inhibitory in broth, but stimulation on spot plates did not always indicate the same phenomenon in broth. PMID:14075051

  4. FOOD MICROORGANISMS INFLUENCING THE GROWTH OF STAPHYLOCOCCUS AUREUS.

    Science.gov (United States)

    GRAVES, R R; FRAZIER, W C

    1963-11-01

    Some 870 cultures of predominating micro-organisms were isolated from market samples of hamburger, fresh pork sausage, fresh fish fillets, stewing beef, frozen chicken pot pie, frozen corn, frozen peas, and pasteurized and raw milk, before and after storage at different temperatures. The isolates were screened for their ability to influence the growth of Staphylococcus aureus strain 196E by means of spot-plate tests on APT and nutrient agars at 25 C. The 438 cultures that influenced the growth of S. aureus were retested on spot plates at 15, 30, and 42 C. After elimination of replicates, the 143 remaining cultures were classified into species, genera, or groups, and 14 different cultures were tested for their influence on the growth of S. aureus in APT broth at 25 C. Over half of the effective cultures inhibited S. aureus and less than half were stimulatory. Pork sausage had the highest proportion of inhibitory cultures, and stewing beef had the lowest. APT agar was better than nutrient agar for screening, and incubation at 15 C gave more effector organisms than at 30 and 42 C. Most of the lactic acid bacteria were inhibitory, but other groups of bacteria contained more stimulatory cultures than inhibitory ones. The three Escherichia coli cultures were stimulatory, but most other Escherichia cultures were inhibitory. Aerobacter and Paracolobactrum isolates were mostly stimulatory. Cultures of other kinds of bacteria were more or less evenly distributed between inhibitory ones and stimulatory ones. Genera containing mostly inhibitory bacteria were Streptococcus, Leuconostoc, and Lactobacillus. Inhibitory species were E. freundii and E. intermedia. Tests with S. aureus in broth indicated that all cultures inhibitory according to spot plates were inhibitory in broth, but stimulation on spot plates did not always indicate the same phenomenon in broth.

  5. Growth kinetics of Staphylococcus aureus on Brie and Camembert cheeses.

    Science.gov (United States)

    Lee, Heeyoung; Kim, Kyungmi; Lee, Soomin; Han, Minkyung; Yoon, Yohan

    2014-05-01

    In this study, we developed mathematical models to describe the growth kinetics of Staphylococcus aureus on natural cheeses. A five-strain mixture of Staph. aureus was inoculated onto 15 g of Brie and Camembert cheeses at 4 log CFU/g. The samples were then stored at 4, 10, 15, 25, and 30 °C for 2-60 d, with a different storage time being used for each temperature. Total bacterial and Staph. aureus cells were enumerated on tryptic soy agar and mannitol salt agar, respectively. The Baranyi model was fitted to the growth data of Staph. aureus to calculate kinetic parameters such as the maximum growth rate in log CFU units (r max; log CFU/g/h) and the lag phase duration (λ; h). The effects of temperature on the square root of r max and on the natural logarithm of λ were modelled in the second stage (secondary model). Independent experimental data (observed data) were compared with prediction and the respective root mean square error compared with the RMSE of the fit on the original data, as a measure of model performance. The total growth of bacteria was observed at 10, 15, 25, and 30 °C on both cheeses. The r max values increased with storage temperature (P<0·05), but a significant effect of storage temperature on λ values was only observed between 4 and 15 °C (P<0·05). The square root model and linear equation were found to be appropriate for description of the effect of storage temperature on growth kinetics (R 2=0·894-0·983). Our results indicate that the models developed in this study should be useful for describing the growth kinetics of Staph. aureus on Brie and Camembert cheeses.

  6. Methicillin-resistant Staphylococcus aureus (MRSA carriage in a dermatology unit

    Directory of Open Access Journals (Sweden)

    Renata L. Pacheco

    2011-01-01

    Full Text Available OBJECTIVE: The aim of this study was to characterize Staphylococcus aureus (MRSA carriage in a dermatology unit. METHODS: This was a prospective and descriptive study. Over the course of 26 weeks, surveillance cultures were collected weekly from the anterior nares and skin of all patients hospitalized in a 20-bed dermatology unit of a tertiary-care hospital. Samples from healthcare workers (HCWS were cultured at the beginning and end of the study. Colonized patients were put under contact precautions, and basic infection control measures were enforced. Staphylococcus aureus colonization pressure was determined monthly. Colonized and non-colonized patients were compared, and isolates were evaluated for antimicrobial susceptibility, SCCmec type, virulence factors, and type. RESULTS: Of the 142 patients evaluated, 64 (45% were colonized by MRSA (39% hospital acquired; 25% community acquired; 36% indeterminate. Despite isolation precautions, hospital-acquired Staphylococcus aureus occurred in addition to the continuous entry of Staphylococcus aureus from the community. Colonization pressure increased from 13% to 59%, and pemphigus and other bullous diseases were associated with MRSA colonization. Eleven out of 71 HCWs (15% were Staphylococcus aureus carriers, although only one worker carried a persistent clone. Of the hospital-acquired MRSA cases, 14/28 (50% were SCCmec type IV (3 PFGE types, 13 were SCCmec type III (46%, and one had an indeterminate type. These types were also present among the community-acquired Staphylococcus aureus isolates. SSCmec type IV isolates were shown to be more susceptible than type III isolates. There were two cases of bloodstream infection, and the pvl and tst virulence genes were absent from all isolates. CONCLUSIONS: Dermatology patients were colonized by community- and hospital-acquired Staphylococcus aureus. Half of the nosocomial Staphylococcus aureus isolates were SCCmec type IV. Despite the identification of

  7. Methicillin-resistant staphylococcus aureus (MRSA) carriage in a dermatology unit

    Science.gov (United States)

    Pacheco, Renata L.; Lobo, Renata D.; Oliveira, Maura S.; Farina, Elthon F.; Santos, Cleide R.; Costa, Silvia F.; Padoveze, Maria Clara; Garcia, Cilmara P.; Trindade, Priscila A.; Quitério, Ligia M.; Rivitti, Evandro A.; Mamizuka, Elsa M.; Levin, Anna S.

    2011-01-01

    OBJECTIVE: The aim of this study was to characterize Staphylococcus aureus (MRSA) carriage in a dermatology unit. METHODS: This was a prospective and descriptive study. Over the course of 26 weeks, surveillance cultures were collected weekly from the anterior nares and skin of all patients hospitalized in a 20-bed dermatology unit of a tertiary-care hospital. Samples from healthcare workers (HCWS) were cultured at the beginning and end of the study. Colonized patients were put under contact precautions, and basic infection control measures were enforced. Staphylococcus aureus colonization pressure was determined monthly. Colonized and non-colonized patients were compared, and isolates were evaluated for antimicrobial susceptibility, SCCmec type, virulence factors, and type. RESULTS: Of the 142 patients evaluated, 64 (45%) were colonized by MRSA (39% hospital acquired; 25% community acquired; 36% indeterminate). Despite isolation precautions, hospital-acquired Staphylococcus aureus occurred in addition to the continuous entry of Staphylococcus aureus from the community. Colonization pressure increased from 13% to 59%, and pemphigus and other bullous diseases were associated with MRSA colonization. Eleven out of 71 HCWs (15%) were Staphylococcus aureus carriers, although only one worker carried a persistent clone. Of the hospital-acquired MRSA cases, 14/28 (50%) were SCCmec type IV (3 PFGE types), 13 were SCCmec type III (46%), and one had an indeterminate type. These types were also present among the community-acquired Staphylococcus aureus isolates. SSCmec type IV isolates were shown to be more susceptible than type III isolates. There were two cases of bloodstream infection, and the pvl and tst virulence genes were absent from all isolates. CONCLUSIONS: Dermatology patients were colonized by community- and hospital-acquired Staphylococcus aureus. Half of the nosocomial Staphylococcus aureus isolates were SCCmec type IV. Despite the identification of colonized

  8. Back to the Future: Penicillin-Susceptible Staphylococcus aureus.

    Science.gov (United States)

    Cheng, Matthew P; René, Pierre; Cheng, Alexandre P; Lee, Todd C

    2016-12-01

    Widespread penicillin usage rapidly resulted in the emergence of penicillin resistance in Staphylococcus aureus. However, new data suggest that penicillin susceptibility may be in a period of renaissance. The objective of our study was to quantify penicillin resistance in methicillin-susceptible Staphylococcus aureus (MSSA) bacteremia. We retrospectively reviewed all adult MSSA bacteremia from April 2010 to April 2015 at the McGill University Health Centre (Montreal, QC, Canada). Susceptibility to penicillin, erythromycin, clindamycin, and trimethoprim-sulfamethoxazole (TMP-SMX) was determined in accordance with the Clinical & Laboratory Standards Institute guidelines. There were 324 unique episodes of MSSA bacteremia. Ninety (28%) isolates were susceptible to penicillin, 229 (71%) to erythromycin, 239 (74%) to clindamycin, and 317 (98%) to TMP-SMX. Isolates that were penicillin resistant were more likely to also be resistant to other antibiotics, but a statistically significant association was apparent only for erythromycin resistance (76/234, 32.2% vs 19/90, 21.1%, P = .04). The median age of patients was 67.5 years (interquartile range 52-78) and overall in-hospital 30-day mortality was 16.3% (53 deaths). After adjustment for patient age, there was no association between penicillin resistance and either intensive care unit admission or death. More than one-quarter of patients with MSSA bacteremia potentially could be treated with parenteral penicillin, which may offer pharmacokinetic advantages over other beta-lactam drugs and potentially improved outcomes. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Bioactive Compounds Produced by Hypoxylon fragiforme against Staphylococcus aureus Biofilms

    Directory of Open Access Journals (Sweden)

    Kamila Tomoko Yuyama

    2017-12-01

    Full Text Available Treating infections organized in biofilms is a challenge due to the resistance of the pathogens against antibiotics and host immune cells. Many fungi grow in a wet environment, favorable for the growth of bacterial biofilms, and we speculated that fungi possess some strategies to control these bacterial biofilms. A fungus identified as Hypoxylon fragiforme, was collected in the Harz Mountains, Germany, and its mycelial culture was fermented in different culture media for 67 days to test its biological potential against bacterial biofilms. Sclerin, sclerin diacid and its 3-methyl monoester (methyl 1-(5-hydroxy-6-carboxylic-2,3,4-trimethylphenyl propionate are here described for the first time from this fungus. Sclerin and its diacid interfered with the biofilm formation of the pathogen Staphylococcus aureus, inhibiting 86% and 80% of the biofilm at 256 μg mL−1, respectively, but not killing the bacterium. Interestingly, the monomethylester of sclerin diacid was inactive. Although these compounds did not possess any activity against a pre-formed biofilm, they prevented its formation at subtoxic concentrations. Furthermore, sclerin and its diacid displayed a high specificity against Staphylococcus aureus, indicating a good strategy against pathogenic biofilms when combined with antibiotics.

  10. Bioactive Compounds Produced by Hypoxylon fragiforme against Staphylococcus aureus Biofilms.

    Science.gov (United States)

    Yuyama, Kamila Tomoko; Chepkirui, Clara; Wendt, Lucile; Fortkamp, Diana; Stadler, Marc; Abraham, Wolf-Rainer

    2017-12-12

    Treating infections organized in biofilms is a challenge due to the resistance of the pathogens against antibiotics and host immune cells. Many fungi grow in a wet environment, favorable for the growth of bacterial biofilms, and we speculated that fungi possess some strategies to control these bacterial biofilms. A fungus identified as Hypoxylon fragiforme, was collected in the Harz Mountains, Germany, and its mycelial culture was fermented in different culture media for 67 days to test its biological potential against bacterial biofilms. Sclerin, sclerin diacid and its 3-methyl monoester (methyl 1-(5-hydroxy-6-carboxylic-2,3,4-trimethylphenyl) propionate) are here described for the first time from this fungus. Sclerin and its diacid interfered with the biofilm formation of the pathogen Staphylococcus aureus, inhibiting 86% and 80% of the biofilm at 256 μg mL-1, respectively, but not killing the bacterium. Interestingly, the monomethylester of sclerin diacid was inactive. Although these compounds did not possess any activity against a pre-formed biofilm, they prevented its formation at subtoxic concentrations. Furthermore, sclerin and its diacid displayed a high specificity against Staphylococcus aureus, indicating a good strategy against pathogenic biofilms when combined with antibiotics.

  11. Staphylococcus aureus entrance into the dairy chain: Tracking S. aureus from dairy cow to cheese

    Directory of Open Access Journals (Sweden)

    Judith Kümmel

    2016-10-01

    Full Text Available Staphylococcus aureus is one of the most important contagious mastitis pathogens in dairy cattle. Due to its zoonotic potential, control of S. aureus is not only of great economic importance in the dairy industry but also a significant public health concern. The aim of this study was to decipher the potential of bovine udder associated S. aureus as reservoir for S. aureus contamination in dairy production and processing. From 18 farms, delivering their milk to an alpine dairy plant for the production of smeared semi-hard and hard cheese. 1176 quarter milk (QM samples of all cows in lactation (n = 294 and representative samples form bulk tank milk (BTM of all farms were surveyed for coagulase positive (CPS and coagulase negative Staphylococci (CNS. Furthermore, samples from different steps of the cheese manufacturing process were tested for CPS and CNS. As revealed by chemometric-assisted FTIR spectroscopy and molecular subtyping (spa typing and multi locus sequence typing, dairy cattle represent indeed an important, yet underreported, entrance point of S. aureus into the dairy chain. Our data clearly show that certain S. aureus subtypes are present in primary production as well as in the cheese processing at the dairy plant. However, although a considerable diversity of S. aureus subtypes was observed in QM and BTM at the farms, only certain S. aureus subtypes were able to enter and persist in the cheese manufacturing at the dairy plant and could be isolated from cheese until day fourteen of ripening. Farm strains belonging to the FTIR cluster B1 and B3, which show genetic characteristics (t2953, ST8, enterotoxin profile: sea/sed/sej of the recently described S. aureus genotype B, most successfully contaminated the cheese production at the dairy plant. Thus our study fosters the hypothesis that genotype B S. aureus represent a specific challenge in control of S. aureus in the dairy chain that requires effective clearance strategies and hygienic

  12. Staphylococcus aureus Entrance into the Dairy Chain: Tracking S. aureus from Dairy Cow to Cheese

    Science.gov (United States)

    Kümmel, Judith; Stessl, Beatrix; Gonano, Monika; Walcher, Georg; Bereuter, Othmar; Fricker, Martina; Grunert, Tom; Wagner, Martin; Ehling-Schulz, Monika

    2016-01-01

    Staphylococcus aureus is one of the most important contagious mastitis pathogens in dairy cattle. Due to its zoonotic potential, control of S. aureus is not only of great economic importance in the dairy industry but also a significant public health concern. The aim of this study was to decipher the potential of bovine udder associated S. aureus as reservoir for S. aureus contamination in dairy production and processing. From 18 farms, delivering their milk to an alpine dairy plant for the production of smeared semi-hard and hard cheese. one thousand hundred seventy six one thousand hundred seventy six quarter milk (QM) samples of all cows in lactation (n = 294) and representative samples form bulk tank milk (BTM) of all farms were surveyed for coagulase positive (CPS) and coagulase negative Staphylococci (CNS). Furthermore, samples from different steps of the cheese manufacturing process were tested for CPS and CNS. As revealed by chemometric-assisted FTIR spectroscopy and molecular subtyping (spa typing and multi locus sequence typing), dairy cattle represent indeed an important, yet underreported, entrance point of S. aureus into the dairy chain. Our data clearly show that certain S. aureus subtypes are present in primary production as well as in the cheese processing at the dairy plant. However, although a considerable diversity of S. aureus subtypes was observed in QM and BTM at the farms, only certain S. aureus subtypes were able to enter and persist in the cheese manufacturing at the dairy plant and could be isolated from cheese until day 14 of ripening. Farm strains belonging to the FTIR cluster B1 and B3, which show genetic characteristics (t2953, ST8, enterotoxin profile: sea/sed/sej) of the recently described S. aureus genotype B, most successfully contaminated the cheese production at the dairy plant. Thus, our study fosters the hypothesis that genotype B S. aureus represent a specific challenge in control of S. aureus in the dairy chain that requires

  13. Comparison of community-onset Staphylococcus argenteus and Staphylococcus aureus sepsis in Thailand: a prospective multicentre observational study

    OpenAIRE

    Chantratita, N.; Wikraiphat, C.; Tandhavanant, S.; Wongsuvan, G.; Ariyaprasert, P.; Suntornsut, P.; Thaipadungpanit, J.; Teerawattanasook, N.; Jutrakul, Y.; Srisurat, N.; Chaimanee, P.; Anukunananchai, J.; Phiphitaporn, S.; Srisamang, P.; Chetchotisakd, P.

    2016-01-01

    : Staphylococcus argenteus is a globally distributed cause of human infection, but diagnostic laboratories misidentify this as Staphylococcus aureus. We determined whether there is clinical utility in distinguishing between the two. A prospective cohort study of community-onset invasive staphylococcal sepsis was conducted in adults at four hospitals in northeast Thailand between 2010 and 2013. Of 311 patients analysed, 58 (19%) were infected with S. argenteus and 253 (81%) with S. aureus. Mos...

  14. Close association between oropharyngeal and rhinopharyngeal colonization with Staphylococcus aureus - clues to new insight of MRSA colonization of the oropharynx

    DEFF Research Database (Denmark)

    Petersen, I S; Larsen, P L; Brandelev, B L

    2013-01-01

    This study provides data on prevalence of Staphylococcus aureus in oropharynx, rhinopharynx and vestibulum nasi. Specimens were taken from these three pharyngeal sites in 346 patients and analysed for S. aureus. Abnormal pharyngeal findings and patient histories were recorded. S. aureus was found...... meticillin-resistant Staphylococcus aureus decolonization regimes....

  15. Identification of Factors Contributing to T-Cell Toxicity of Staphylococcus aureus Clinical Isolates▿

    OpenAIRE

    Collins, James; Buckling, Angus; Massey, Ruth C.

    2008-01-01

    We examined the ability of 206 clinical isolates of Staphylococcus aureus to lyse T cells and found differences between Agr groups. We found that the beta and delta hemolysins are involved and that methicillin-resistant S. aureus strains are less toxic than methicillin-susceptible S. aureus strains.

  16. Phenotypic and genotypic antimicrobial resistance traits of foodborne Staphylococcus aureus isolates from Shanghai

    Science.gov (United States)

    Staphylococcus aureus is a recognized pathogen in humans, which causes nosocomial infections and food poisoning. The transmission of antibiotic resistant S. aureus (ARSA), especially methicillin-resistant S. aureus (MRSA), between food products and humans has become a serious problem. Hence, it is n...

  17. Long-term cortisol levels are not associated with nasal carriage of Staphylococcus aureus

    NARCIS (Netherlands)

    Manenschijn, L.; Jetten, A.M.; Wamel, W.J.B. van; Tavakol, M.; Koper, J.W.; Akker, E.L.T. van den; Belkum, A. van; Rossum, E.F.C. van

    2012-01-01

    Staphylococcus aureus (S. aureus) colonizes the anterior nares in part of the population and the persistent carrier state is associated with increased infection risk. Knowledge concerning the determinants of S. aureus nasal carriage is limited. Previously, we found that glucocorticoid receptor

  18. Rapid Identification of Staphylococcus aureus Directly from Bactec Blood Culture Broth by the BinaxNOW S. aureus Test

    OpenAIRE

    Qian, Qinfang; Eichelberger, Karen; Kirby, James E.

    2014-01-01

    The BinaxNOW Staphylococcus aureus testing showed sensitivity, specificity, and positive and negative predicative values of 97.6%, 100%, 100%, and 98.4%, respectively, for identification of S. aureus from Bactec blood culture broth. Importantly, the test performed equally well on aerobic and anaerobic culture broth.

  19. Proteome changes of Caenorhabditis elegans upon a Staphylococcus aureus infection

    Directory of Open Access Journals (Sweden)

    Schoofs Liliane

    2010-02-01

    Full Text Available Abstract Background The success of invertebrates throughout evolution is an excellent illustration of the efficiency of their defence strategies. Caenorhabditis elegans has proven to be an appropriate model for transcriptome studies of host-pathogen interactions. The aim of this paper is to complement this knowledge by investigating the worm's response to a Staphylococcus aureus infection through a 2-dimensional differential proteomics approach. Results Different types of growth media in combination with either E. coli OP50 or Staphylococcus aureus were tested for an effect on the worm's lifespan. LB agar was chosen and C. elegans samples were collected 1 h, 4 h, 8 h and 24 h post S. aureus infection or E. coli incubation. Proteomics analyses resulted in the identification of 130 spots corresponding to a total of 108 differentially expressed proteins. Conclusions Exploring four time-points discloses a dynamic insight of the reaction against a gram-positive infection at the level of the whole organism. The remarkable upregulation after 8 h and 24 h of many enzymes involved in the citric acid cycle might illustrate the cost of fighting off an infection. Intriguing is the downregulation of chaperone molecules, which are presumed to serve a protective role. A comparison with a similar experiment in which C. elegans was infected with the gram-negative Aeromonas hydrophila reveals that merely 9% of the identified spots, some of which even exhibiting an opposite regulation, are present in both studies. Hence, our findings emphasise the complexity and pathogen-specificity of the worm's immune response and form a firm basis for future functional research. Reviewers This article was reviewed by Itai Yanai, Dieter Wolf and Torben Luebke (nominated by Walter Lutz.

  20. Evaluation of vancomycin MIC creep in Staphylococcus aureus.

    Science.gov (United States)

    Diaz, Raquel; Ramalheira, Elmano; Afreixo, Vera; Gago, Bruno

    2017-09-01

    Vancomycin is the primary treatment for methicillin-resistant Staphylococcus aureus (MRSA). However, an increasing proportion of MRSA isolates with high minimum inhibitory concentrations (MICs) within the susceptible range (vancomycin 'MIC creep') is being observed. The aim of this study was to assess the vancomycin MIC distribution for S. aureus isolates over a period of 4 years in Centro Hospitalar Baixo Vouga (Aveiro, Portugal) and to identify differences in vancomycin MIC determined by different susceptibility testing methods. For each S. aureus isolate, the vancomycin MIC was assayed by the VITEK ® 2 automated system and the broth microdilution testing method. The results showed significant differences in vancomycin MIC by different methods (P=0.021, sign test) and did not suggest the presence of vancomycin MIC creep during the study period. Vancomycin MIC creep is a regional problem, therefore it can only be assessed through the evaluation of local susceptibility profiles, and antibiogram based on real MIC assay should be an essential element in local MRSA infection clinical management. Copyright © 2017 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.

  1. Methicillin resistance in Staphylococcus aureus: mechanisms and modulation.

    Science.gov (United States)

    Stapleton, Paul D; Taylor, Peter W

    2002-01-01

    Staphylococcus aureus is a major pathogen both within hospitals and in the community. Methicillin, a beta-lactam antibiotic, acts by inhibiting penicillin-binding proteins (PBPs) that are involved in the synthesis of peptidoglycan, an essential mesh-like polymer that surrounds the cell. S. aureus can become resistant to methicillin and other beta-lactam antibiotics through the expression of a foreign PBP, PBP2a, that is resistant to the action of methicillin but which can perform the functions of the host PBPs. Methicillin-resistant S. aureus isolates are often resistant to other classes of antibiotics (through different mechanisms) making treatment options limited, and this has led to the search for new compounds active against these strains. An understanding of the mechanism of methicillin resistance has led to the discovery of accessory factors that influence the level and nature of methicillin resistance. Accessory factors, such as Fem factors, provide possible new targets, while compounds that modulate methicillin resistance such as epicatechin gallate, derived from green tea, and corilagin, provide possible lead compounds for development of inhibitors.

  2. Persister formation in Staphylococcus aureus is associated with ATP depletion

    Energy Technology Data Exchange (ETDEWEB)

    Conlon, Brian P.; Rowe, Sarah E.; Gandt, Autumn Brown; Nuxoll, Austin S.; Donegan, Niles P.; Zalis, Eliza A.; Clair, Geremy; Adkins, Joshua N.; Cheung, Ambrose L.; Lewis, Kim

    2016-04-18

    Persisters are dormant phenotypic variants of bacterial cells that are tolerant to killing by antibiotics1. Persisters are associated with chronic bacterial infection and antibiotic treatment failure. In Escherichia coli, toxin/antitoxin (TA) modules are responsible for persister formation. The mechanism of persister formation in Gram positive bacteria is unknown. Staphylococcus aureus is a major human pathogen, responsible for a variety of chronic and relapsing infections such as osteomyelitis, endocarditis and infections of implanted devices. Deleting TA modules in S. aureus did not affect the level of persisters. Here we show that S. aureus persisters are produced due to a stochastic entrance to stationary phase accompanied by a drop in intracellular ATP. Cells expressing stationary state markers are present throughout the growth phase, increasing in frequency with cell density. Cell sorting revealed that expression of stationary markers was associated with a 100-1000 fold increased likelihood of survival to antibiotic challenge. We find that the antibiotic tolerance of these cells is due to a drop in intracellular ATP. The ATP level of the cell is predictive of bactericidal antibiotic efficacy and explains bacterial tolerance to antibiotic treatment.

  3. Beta-hemolysin promotes skin colonization by Staphylococcus aureus.

    Science.gov (United States)

    Katayama, Yuki; Baba, Tadashi; Sekine, Miwa; Fukuda, Minoru; Hiramatsu, Keiichi

    2013-03-01

    Colonization by Staphylococcus aureus is a characteristic feature of several inflammatory skin diseases and is often followed by epidermal damage and invasive infection. In this study, we investigated the mechanism of skin colonization by a virulent community-acquired methicillin-resistant S. aureus (CA-MRSA) strain, MW2, using a murine ear colonization model. MW2 does not produce a hemolytic toxin, beta-hemolysin (Hlb), due to integration of a prophage, Sa3mw, inside the toxin gene (hlb). However, we found that strain MW2 bacteria that had successfully colonized murine ears included derivatives that produced Hlb. Genome sequencing of the Hlb-producing colonies revealed that precise excision of prophage Sa3mw occurred, leading to reconstruction of the intact hlb gene in their chromosomes. To address the question of whether Hlb is involved in skin colonization, we constructed MW2-derivative strains with and without the Hlb gene and then subjected them to colonization tests. The colonization efficiency of the Hlb-producing mutant on murine ears was more than 50-fold greater than that of the mutant without hlb. Furthermore, we also showed that Hlb toxin had elevated cytotoxicity for human primary keratinocytes. Our results indicate that S. aureus Hlb plays an important role in skin colonization by damaging keratinocytes, in addition to its well-known hemolytic activity for erythrocytes.

  4. Action of Lipases of Staphylococcus aureus on Milk Fat1

    Science.gov (United States)

    Vadehra, D. V.; Harmon, L. G.

    1965-01-01

    The activity of the lipase(s) of two strains of coagulase-positive Staphylococcus aureus was determined in milk fat incubated at 15, 22, and 30 C for 8 days. Total fat hydrolysis was measured by acid degree values (ADV). Neutral lipids were separated into component groups on a Florisil column. Free fatty acids were determined by temperature-programmed gas-liquid chromatography. The ADV were 25 to 50% greater at 22 than at 15 C and 4 to 7 times greater at 30 than at 22 C. The lipases liberated as much as 0.48 g of fatty acids per gram of fat during 8 days at 30 C. The enzyme showed a predilection for the palmitic acid-glycerol bond. Addition of fatty acids C14 to C18 inclusive to inoculated sterile skim milk caused inhibition of S. aureus as follows: (i) complete at 0.05 and 0.10% concentration of C10 and (ii) partial at 0.05 and complete at 0.10% concentration of C8. The samples showing inhibition were negative for peptonization, coagulase, and change in pH. Addition of oleic and stearic acid to sterile skim milk inoculated with S. aureus resulted in an increase in nonprotein nitrogen, and the C4 to C12 acids caused a decrease in protease activity. PMID:14325270

  5. Planktonic aggregates of Staphylococcus aureus protect against common antibiotics.

    Science.gov (United States)

    Haaber, Jakob; Cohn, Marianne Thorup; Frees, Dorte; Andersen, Thorbjørn Joest; Ingmer, Hanne

    2012-01-01

    Bacterial cells are mostly studied during planktonic growth although in their natural habitats they are often found in communities such as biofilms with dramatically different physiological properties. We have examined another type of community namely cellular aggregates observed in strains of the human pathogen Staphylococcus aureus. By laser-diffraction particle-size analysis (LDA) we show, for strains forming visible aggregates, that the aggregation starts already in the early exponential growth phase and proceeds until post-exponential phase where more than 90% of the population is part of the aggregate community. Similar to some types of biofilm, the structural component of S. aureus aggregates is the polysaccharide intercellular adhesin (PIA). Importantly, PIA production correlates with the level of aggregation whether altered through mutations or exposure to sub-inhibitory concentrations of selected antibiotics. While some properties of aggregates resemble those of biofilms including increased mutation frequency and survival during antibiotic treatment, aggregated cells displayed higher metabolic activity than planktonic cells or cells in biofilm. Thus, our data indicate that the properties of cells in aggregates differ in some aspects from those in biofilms. It is generally accepted that the biofilm life style protects pathogens against antibiotics and the hostile environment of the host. We speculate that in aggregate communities S. aureus increases its tolerance to hazardous environments and that the combination of a biofilm-like environment with mobility has substantial practical and clinical importance.

  6. Biochemical characters and antibiotic susceptibility of Staphylococcus aureus isolates.

    Science.gov (United States)

    Chakraborty, Subhankari Prasad; Mahapatra, Santanu Kar; Roy, Somenath

    2011-06-01

    To observe the biochemical characters and antibiotic susceptibility of isolated Staphylococcus aureus (S. auerus) strains against some conventional and traditional antibiotics. Thirty post operative pathogenic isolated S. aureus strains were used in this study. Bacterial culture was done in Mueller-Hinton broth at 37 °C. Characters of these strains were determined by traditional biochemical tests such as hydrolysis test of gelatin, urea, galactose, starch and protein, and fermentation of lactose and sucrose. Antibiotic susceptibility were carried out by minimum inhibitory concentration test, minium bactericidal concentration test, disc agar diffusion test and brain heart infusion oxacillin screening agar. From this study, it was observed that 100% S. aureus isolates showed positive results in gelatin, urea and galactose hydrolysis test, 50% isolates were positive in starch hydrolysis test, 35% in protein hydrolysis test, 100% isolates in lactose fermenting test, but no isolate was positive in sucrose fermenting test. Antibiotic susceptibility testing suggested that 20% of isolates were resistant to kanamycin and 46.67% were resistant to oxacillin. These findings show that all these isolates have gelatin, urea, galactose hydrolysis and lactose fermenting activity. 20% of these isolates were resistant to kanamycin and 46.67% were resistant to oxacillin.

  7. Necroptosis Promotes Staphylococcus aureus Clearance by Inhibiting Excessive Inflammatory Signaling

    Directory of Open Access Journals (Sweden)

    Kipyegon Kitur

    2016-08-01

    Full Text Available Staphylococcus aureus triggers inflammation through inflammasome activation and recruitment of neutrophils, responses that are critical for pathogen clearance but are associated with substantial tissue damage. We postulated that necroptosis, cell death mediated by the RIPK1/RIPK3/MLKL pathway, would function to limit pathological inflammation. In models of skin infection or sepsis, Mlkl−/− mice had high bacterial loads, an inability to limit interleukin-1b (IL-1b production, and excessive inflammation. Similarly, mice treated with RIPK1 or RIPK3 inhibitors had increased bacterial loads in a model of sepsis. Ripk3−/− mice exhibited increased staphylococcal clearance and decreased inflammation in skin and systemic infection, due to direct effects of RIPK3 on IL-1b activation and apoptosis. In contrast to Casp1/4−/− mice with defective S. aureus killing, the poor outcomes of Mlkl−/− mice could not be attributed to impaired phagocytic function. We conclude that necroptotic cell death limits the pathological inflammation induced by S. aureus.

  8. Staphylococcus aureus CcpA affects biofilm formation.

    Science.gov (United States)

    Seidl, Kati; Goerke, Christiane; Wolz, Christiane; Mack, Dietrich; Berger-Bächi, Brigitte; Bischoff, Markus

    2008-05-01

    Biofilm formation in Staphylococcus aureus under in vitro growth conditions is generally promoted by high concentrations of sugar and/or salts. The addition of glucose to routinely used complex growth media triggered biofilm formation in S. aureus strain SA113. Deletion of ccpA, coding for the catabolite control protein A (CcpA), which regulates gene expression in response to the carbon source, abolished the capacity of SA113 to form a biofilm under static and flow conditions, while still allowing primary attachment to polystyrene surfaces. This suggested that CcpA mainly affects biofilm accumulation and intercellular aggregation. trans-Complementation of the mutant with the wild-type ccpA allele fully restored the biofilm formation. The biofilm produced by SA113 was susceptible to sodium metaperiodate, DNase I, and proteinase K treatment, indicating the presence of polysaccharide intercellular adhesin (PIA), protein factors, and extracellular DNA (eDNA). The investigation of several factors which were reported to influence biofilm formation in S. aureus (arlRS, mgrA, rbf, sarA, atl, ica, citZ, citB, and cidABC) showed that CcpA up-regulated the transcription of cidA, which was recently shown to contribute to eDNA production. Moreover, we showed that CcpA increased icaA expression and PIA production, presumably over the down-regulation of the tricarboxylic acid cycle genes citB and citZ.

  9. Staphylococcus aureus CcpA Affects Biofilm Formation▿

    Science.gov (United States)

    Seidl, Kati; Goerke, Christiane; Wolz, Christiane; Mack, Dietrich; Berger-Bächi, Brigitte; Bischoff, Markus

    2008-01-01

    Biofilm formation in Staphylococcus aureus under in vitro growth conditions is generally promoted by high concentrations of sugar and/or salts. The addition of glucose to routinely used complex growth media triggered biofilm formation in S. aureus strain SA113. Deletion of ccpA, coding for the catabolite control protein A (CcpA), which regulates gene expression in response to the carbon source, abolished the capacity of SA113 to form a biofilm under static and flow conditions, while still allowing primary attachment to polystyrene surfaces. This suggested that CcpA mainly affects biofilm accumulation and intercellular aggregation. trans-Complementation of the mutant with the wild-type ccpA allele fully restored the biofilm formation. The biofilm produced by SA113 was susceptible to sodium metaperiodate, DNase I, and proteinase K treatment, indicating the presence of polysaccharide intercellular adhesin (PIA), protein factors, and extracellular DNA (eDNA). The investigation of several factors which were reported to influence biofilm formation in S. aureus (arlRS, mgrA, rbf, sarA, atl, ica, citZ, citB, and cidABC) showed that CcpA up-regulated the transcription of cidA, which was recently shown to contribute to eDNA production. Moreover, we showed that CcpA increased icaA expression and PIA production, presumably over the down-regulation of the tricarboxylic acid cycle genes citB and citZ. PMID:18347047

  10. Surgimiento y diseminación de Staphylococcus aureus meticilinorresistente Staphylococcus aureus methicillin-resistant: emergence and dissemination

    Directory of Open Access Journals (Sweden)

    Maria Elena Velázquez-Meza

    2005-10-01

    Full Text Available Las infecciones nosocomiales ocasionadas por cepas de Staphylococcus aureus meticilinorresistentes (SAMR son un problema de salud importante en todo el mundo. Este microorganismo produce una gran variedad de infecciones incluyendo osteomielitis, endocarditis invasora, artritis séptica y septicemia. La multirresistencia es un factor que influye en la persistencia de los SAMR dentro del ámbito hospitalario. La introducción de técnicas de tipificación molecular dentro de las investigaciones epidemiológicas ha provisto nuevas herramientas para conocer el origen y las vías de diseminación de este microorganismo. Una de las conclusiones importantes que han surgido de este tipo de estudios es que un número pequeño de clonas son las responsables de las infecciones estafilocócicas en todo el mundo.Nosocomial infections due to methicillin-resistant Staphylococcus aureus (MRSA is an important health problem worldwide. This microorganism causes a variety of clinical infections, including osteomyelitis, invasive endocarditis, septic arthritis and septicemia. Antimicrobial resistance is a factor that influences the persistence of MRSA in the hospital environment. The introduction of molecular typing techniques in epidemiological investigations has provided new tools for identifying the microorganism's origin and routes of dissemination. One of the most important conclusions that have resulted from these types of studies is that a small number of clones are responsible for most of the staphylococcal infections throughout the world.

  11. Comprehensive identification of mutations responsible for heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA)-to-VISA conversion in laboratory-generated VISA strains derived from hVISA clinical strain Mu3.

    Science.gov (United States)

    Matsuo, Miki; Cui, Longzhu; Kim, Jeeyoung; Hiramatsu, Keiichi

    2013-12-01

    Heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) spontaneously produces VISA cells within its cell population at a frequency of 10(-6) or greater. We established a total of 45 VISA mutant strains independently obtained from hVISA Mu3 and its related strains by one-step vancomycin selection. We then performed high-throughput whole-genome sequencing of the 45 strains and their parent strains to identify the genes involved in the hVISA-to-VISA phenotypic conversion. A comparative genome study showed that all the VISA strains tested carried a unique set of mutations. All of the 45 VISA strains carried 1 to 4 mutations possibly affecting the expression of a total of 48 genes. Among them, 32 VISA strains carried only one gene affected by a single mutation. As many as 20 genes in more than eight functional categories were affected in the 32 VISA strains, which explained the extremely high rates of the hVISA-to-VISA phenotypic conversion. Five genes, rpoB, rpoC, walK, pbp4, and pp2c, were previously reported as being involved in vancomycin resistance. Fifteen remaining genes were newly identified as associated with vancomycin resistance in this study. The gene most frequently affected (6 out of 32 strains) was cmk, which encodes cytidylate kinase, followed closely by rpoB (5 out of 32), encoding the β subunit of RNA polymerase. A mutation prevalence study also revealed a sizable number of cmk mutants among clinical VISA strains (7 out of 38 [18%]). Reduced cytidylate kinase activity in cmk mutant strains is proposed to contribute to the hVISA-to-VISA phenotype conversion by thickening the cell wall and reducing the cell growth rate.

  12. Antibiofilm Effect of Octenidine Hydrochloride on Staphylococcus aureus, MRSA and VRSA

    Directory of Open Access Journals (Sweden)

    Mary Anne Roshni Amalaradjou

    2014-05-01

    Full Text Available Millions of indwelling devices are implanted in patients every year, and staphylococci (S. aureus, MRSA and vancomycin-resistant S. aureus (VRSA are responsible for a majority of infections associated with these devices, thereby leading to treatment failures. Once established, staphylococcal biofilms become resistant to antimicrobial treatment and host response, thereby serving as the etiological agent for recurrent infections. This study investigated the efficacy of octenidine hydrochloride (OH for inhibiting biofilm synthesis and inactivating fully-formed staphylococcal biofilm on different matrices in the presence and absence of serum protein. Polystyrene plates and stainless steel coupons inoculated with S. aureus, MRSA or VRSA were treated with OH (zero, 0.5, one, 2 mM at 37 °C for the prevention of biofilm formation. Additionally, the antibiofilm effect of OH (zero, 2.5, five, 10 mM on fully-formed staphylococcal biofilms on polystyrene plates, stainless steel coupons and urinary catheters was investigated. OH was effective in rapidly inactivating planktonic and biofilm cells of S. aureus, MRSA and VRSA on polystyrene plates, stainless steel coupons and urinary catheters in the presence and absence of serum proteins. The use of two and 10 mM OH completely inactivated S. aureus planktonic cells and biofilm (>6.0 log reduction on all matrices tested immediately upon exposure. Further, confocal imaging revealed the presence of dead cells and loss in biofilm architecture in the OH-treated samples when compared to intact live biofilm in the control. Results suggest that OH could be applied as an effective antimicrobial to control biofilms of S. aureus, MRSA and VRSA on appropriate hospital surfaces and indwelling devices.

  13. Methicillin resistant Staphylococcus aureus (MRSA in India: Prevalence & susceptibility pattern

    Directory of Open Access Journals (Sweden)

    Indian Network for Surveillance of Antimicrobial Resistance (INSAR group, India

    2013-01-01

    Full Text Available Background & objectives: Methicillin resistant Staphylococcus aureus (MRSA is endemic in India and is a dangerous pathogen for hospital acquired infections. This study was conducted in 15 Indian tertiary care centres during a two year period from January 2008 to December 2009 to determine the prevalence of MRSA and susceptibility pattern of S. aureus isolates in India. Methods: All S. aureus isolates obtained during the study period in the participating centres were included in the study. Each centre compiled their data in a predefined template which included data of the antimicrobial susceptibility pattern, location of the patient and specimen type. The data in the submitted templates were collated and analysed. Results: A total of 26310 isolates were included in the study. The overall prevalence of methicillin resistance during the study period was 41 per cent. Isolation rates for MRSA from outpatients, ward inpatients and ICU were 28, 42 and 43 per cent, respectively in 2008 and 27, 49 and 47 per cent, respectively in 2009. The majority of S. aureus isolates was obtained from patients with skin and soft tissue infections followed by those suffering from blood stream infections and respiratory infections. Susceptibility to ciprofloxacin was low in both MSSA (53% and MRSA (21%. MSSA isolates showed a higher susceptibility to gentamicin, co-trimoxazole, erythromycin and clindamycin as compared to MRSA isolates. No isolate was found resistant to vancomycin or linezolid. Interpretation & conclusions: The study showed a high level of MRSA in our country. There is a need to study epidemiology of such infections. Robust antimicrobial stewardship and strengthened infection control measures are required to prevent spread and reduce emergence of resistance.

  14. Applying Convergent Immunity to Innovative Vaccines Targeting Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Michael R Yeaman

    2014-09-01

    Full Text Available Recent perspectives forecast a new paradigm for future 3rd generation vaccines based on commonalities found in diverse pathogens or convergent immune defenses to such pathogens. For Staphylococcus aureus, recurring infections and a limited success of vaccines containing S. aureus antigens imply that native antigens induce immune responses insufficient for optimal efficacy. These perspectives exemplify the need to apply novel vaccine strategies to high priority pathogens. One such approach can be termed convergent immunity, where antigens from non-target organisms that contain epitope homologues found in the target organism are applied in vaccines. This approach aims to evoke atypical immune defenses via synergistic processes that 1 afford protective efficacy; 2 target an epitope from one organism that contributes to protective immunity against another; 3 cross-protect against multiple pathogens occupying a common anatomic or immunologic niche; and/or 4 overcome immune subversion or avoidance strategies of target pathogens. Thus, convergent immunity has a potential to promote protective efficacy not usually elicited by native antigens from a target pathogen. Variations of this concept have been mainstays in the history of viral and bacterial vaccine development. A more far-reaching example is the pre–clinical evidence that specific fungal antigens can induce cross-kingdom protection against bacterial pathogens. This trans-kingdom protection has been demonstrated in preclinical studies of the recombinant Candida albicans agglutinin-like sequence 3 protein (rAls3 where it was shown that a vaccine containing rAls3 provides homologous protection against C. albicans, heterologous protection against several other Candida species, and convergent protection against several strains of S. aureus. Convergent immunity reflects an intriguing new approach to designing and developing vaccine antigens and is considered here in the context of vaccines to target

  15. Biofilm formation of Staphylococcus aureus dairy isolates representing different genotypes.

    Science.gov (United States)

    Thiran, E; Di Ciccio, P A; Graber, H U; Zanardi, E; Ianieri, A; Hummerjohann, J

    2017-11-15

    The objective of this study was to compare the biofilm-forming capabilities of different genotypes of Staphylococcus aureus dairy isolates from Switzerland and northern Italy, including Staph. aureus genotype B (GTB) and methicillin-resistant Staph. aureus (MRSA). We hypothesized that biofilm formation might be more pronounced in the contagious GTB isolates compared with other genotypes affecting individual animals. Twenty-four dairy isolates, including 9 MRSA, were further characterized by genotyping by using ribosomal spacer PCR, spa typing, biofilm formation under static and dynamic conditions, and scanning electron microscopy. The GTB isolates (n = 6) were more able to form biofilms than other genotypes at 37°C and at 20°C after 48 and 72 h of incubation in the static assay using polystyrene microtiter plates. This result was supported by scanning electron micrographs showing a GTB isolate producing strong biofilm with extracellular matrix in contrast to a genotype C isolate. Furthermore, none of the MRSA isolates formed strong biofilms in the static assay. However, some MRSA produced low or moderate amounts of biofilm depending on the applied conditions. Under dynamic conditions, a much more diverse situation was observed. The ability of GTB isolates to be strong biofilm formers was not observed in all cases, emphasizing the importance of growth conditions for the expression of biofilm-related genes. No specific genotype, spa type, or MRSA isolate could be categorized significantly into one level of biofilm formation. Nineteen percent of isolates behaved similarly under static and dynamic conditions. The results of this study expand our knowledge of different dairy-related Staph. aureus subtypes and indicate the benefit of genotyping when biofilms are studied. The Authors. Published by the Federation of Animal Science Societies and Elsevier Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY

  16. Staphylococcus aureus biofilms: Nemesis of endoscopic sinus surgery.

    Science.gov (United States)

    Singhal, Deepti; Foreman, Andrew; Jervis-Bardy, Joshua; Bardy, Josh-Jervis; Wormald, Peter-John

    2011-07-01

    Chronic rhinosinusitis (CRS) patients with biofilms have persistent postoperative symptoms, ongoing mucosal inflammation, and recurrent infections. Recent evidence suggests that biofilms of differing species confer varying disease profiles in CRS patients. We aimed to prospectively investigate the effects of Staphylococcus aureus, Pseudomonas aeruginosa, Haemophilus influenzae, and fungal biofilms on outcomes following endoscopic sinus surgery (ESS). Prospective blinded study. In this prospective blinded study, 39 patients undergoing ESS for CRS assessed their symptoms preoperatively using internationally accepted standardized symptom scoring systems and quality-of-life measures (10-point visual analog scale, Sino-Nasal Outcome Test-20, global severity of CRS). Their sinonasal mucosa was graded (Lund-Kennedy scale) and extent of radiologic disease on computed tomography scans scored (Lund-McKay scale). Random sinonasal tissue samples were assessed for different bacterial species forming biofilms by using fluorescent in-situ hybridization and confocal laser microscopy. For 12 months after surgery, CRS symptoms, quality of life, and objective evidence of persisting disease were assessed by using the preoperative tools. Different bacterial species combinations were found in 30 of 39 patients; 60% of these 30 biofilms were polymicrobial biofilms and 70% had S aureus biofilms. Preoperative nasendoscopy and radiologic disease severity were significantly worse in patients with multiple biofilms (P = .02 and P = .01, respectively), and they had worse postsurgery mucosal outcomes on endoscopy (P = .01) requiring significantly more postoperative visits (P = .04). Those with S aureus biofilms progressed poorly with their symptom scores and quality-of-life outcomes, with significant differences in nasendoscopy scores (P = .007). S. aureus biofilms play a dominant role in negatively affecting outcomes of ESS with persisting postoperative symptoms, ongoing mucosal inflammation

  17. Applying Convergent Immunity to Innovative Vaccines Targeting Staphylococcus aureus

    Science.gov (United States)

    Yeaman, Michael R.; Filler, Scott G.; Schmidt, Clint S.; Ibrahim, Ashraf S.; Edwards, John E.; Hennessey, John P.

    2014-01-01

    Recent perspectives forecast a new paradigm for future “third generation” vaccines based on commonalities found in diverse pathogens or convergent immune defenses to such pathogens. For Staphylococcus aureus, recurring infections and a limited success of vaccines containing S. aureus antigens imply that native antigens induce immune responses insufficient for optimal efficacy. These perspectives exemplify the need to apply novel vaccine strategies to high-priority pathogens. One such approach can be termed convergent immunity, where antigens from non-target organisms that contain epitope homologs found in the target organism are applied in vaccines. This approach aims to evoke atypical immune defenses via synergistic processes that (1) afford protective efficacy; (2) target an epitope from one organism that contributes to protective immunity against another; (3) cross-protect against multiple pathogens occupying a common anatomic or immunological niche; and/or (4) overcome immune subversion or avoidance strategies of target pathogens. Thus, convergent immunity has a potential to promote protective efficacy not usually elicited by native antigens from a target pathogen. Variations of this concept have been mainstays in the history of viral and bacterial vaccine development. A more far-reaching example is the pre-clinical evidence that specific fungal antigens can induce cross-kingdom protection against bacterial pathogens. This trans-kingdom protection has been demonstrated in pre-clinical studies of the recombinant Candida albicans agglutinin-like sequence 3 protein (rAls3) where it was shown that a vaccine containing rAls3 provides homologous protection against C. albicans, heterologous protection against several other Candida species, and convergent protection against several strains of S. aureus. Convergent immunity reflects an intriguing new approach to designing and developing vaccine antigens and is considered here in the context of vaccines to target S

  18. Survival of vancomycin-intermediate Staphylococcus aureus on hospital surfaces.

    Science.gov (United States)

    Zarpellon, M N; Gales, A C; Sasaki, A L; Selhorst, G J; Menegucci, T C; Cardoso, C L; Garcia, L B; Tognim, M C B

    2015-08-01

    Contaminated surfaces play an important role in the transmission of certain pathogens that are responsible for healthcare-associated infections. Although previous studies have shown that meticillin-resistant Staphylococcus aureus (MRSA) can survive on dry surfaces at room temperature, no published data regarding vancomycin-intermediate S. aureus (VISA) are available to date. To compare the survival time on different types of surfaces, cell-surface hydrophobicity, adherence to abiotic surfaces and biofilm formation of meticillin-susceptible S. aureus (MSSA), MRSA and VISA. Survival of the S. aureus strains was tested on latex, cotton fabric, vinyl flooring and formica. Cell-surface hydrophobicity was determined using the hydrocarbon interaction affinity method. Adhesion to abiotic surfaces was tested on granite, latex (gloves), glass, vinyl flooring and formica. Biofilm formation was evaluated at 6, 12, 24 and 48 h. All of the samples survived on the vinyl flooring and formica for at least 40 days. VISA survived on both surfaces for more than 45 days. All of the strains were highly hydrophobic. VISA adhered to latex, vinyl flooring and formica. Biofilm formation increased for all of the tested strains within 6-24 h. VISA present high survival, adherence and cell-surface hydrophobicity. Therefore, as the treatment of patients with VISA is a significant challenge for clinicians, greater care with cleaning and disinfection of different types of surfaces in healthcare facilities is recommended because these may become important reservoirs of multi-resistant pathogens. Copyright © 2015 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  19. Typing of vancomycin-resistant enterococci from Danish hospitals

    DEFF Research Database (Denmark)

    Lester, Camilla H.; Olsen, Stefan S.; Schønheyder, Henrik Carl

    2009-01-01

    complex 17 (CC17) has been associated with nosocomial outbreaks in five continents. The aim of the present study was to elucidate the molecular epidemiology of VRE in Denmark. Methods: From January 2005 through October 2008, 61 vancomycin resistant enterococcal isolates causing invasive as well as non......-invasive infections were referred by seven of the 15 Danish departments of clinical microbiology to Statens Serum Institut. All isolates were identified to species level by PCR, MICs of vancomycin were determined (Trek Diagnostic Systems, UK), and the presence of vanA, vanB and vanC genes were detected by PCR. Multi...

  20. Antibiotic resistance and molecular epidemiology of Staphylococcus aureus in Nigeria

    Directory of Open Access Journals (Sweden)

    Oyedara Omotayo

    2011-05-01

    Full Text Available Abstract Background Staphylococcus aureus is an important pathogen causing a wide range of infections in the hospital and community setting. In order to have adequate information for treatment of S. aureus infections, it is crucial to understand the trends in the antibiotic-resistance patterns. In addition, the occurrence and changes in types of S. aureus, clonal identities, and their geographic spread is essential for the establishment of adequate infection control programmes. In this study, 68 S. aureus isolates obtained from clinical and non-clinical sources in Nigeria between January and April 2009 were characterized using phenotypic and molecular methods. Results All the S. aureus isolates were susceptible to teicoplanin, vancomycin, phosphomycin, fusidic acid, rifampicin, daptomycin, mupirocin, linezolid and tigecycline. Sixteen percent of the isolates were resistant to oxacillin, while 55% and 72% of isolates were resistant to tetracycline and trimethoprim/sulphamethoxazole (cotrimoxazole, respectively (Table 1. There was excellent correlation between the broth microdilution assay and detection of antibiotic resistance genes by the multiplex PCR, in the determination of S. aureus resistance to erythromycin, gentamicin, methicillin and tetracycline. A total of 28 spa types were identified in the study, and the predominant spa type among the methicillin-susceptible S. aureus (MSSA isolates was t084 (13 isolates. The t037-ST241-SCCmecIII type was the only clone identified in Maiduguri (North-East Nigeria while in South-West Nigeria, diversity among the MRSA isolates (t451-ST8-SCCmecV; t008-ST94-SCCmecIV; t002-ST5-SCCmecV; t064-ST8-SCCmecV was observed. The toxin genes seh and etd were detected in isolates affiliated with clonal complexes CC1, CC80 and sequence type ST25, respectively. The proportion of PVL-positive isolates among MSSA was high (40%. Most of the PVL-positive MSSA isolates were obtained from wound infections and associated

  1. Shedding of Staphylococcus aureus and methicillin-resistant Staphylococcus aureus from adult and pediatric bathers in marine waters

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    Sinigalliano Christopher D

    2011-01-01

    Full Text Available Abstract Background Staphylococcus aureus including methicillin resistant S. aureus, MRSA, are human colonizing bacteria that commonly cause opportunistic infections primarily involving the skin in otherwise healthy individuals. These infections have been linked to close contact and sharing of common facilities such as locker rooms, schools and prisons Waterborne exposure and transmission routes have not been traditionally associated with S. aureus infections. Coastal marine waters and beaches used for recreation are potential locations for the combination of high numbers of people with close contact and therefore could contribute to the exposure to and infection by these organisms. The primary aim of this study was to evaluate the amount and characteristics of the shedding of methicillin sensitive S. aureus, MSSA and MRSA by human bathers in marine waters. Results Nasal cultures were collected from bathers, and water samples were collected from two sets of pools designed to isolate and quantify MSSA and MRSA shed by adults and toddlers during exposure to marine water. A combination of selective growth media and biochemical and polymerase chain reaction analysis was used to identify and perform limited characterization of the S. aureus isolated from the water and the participants. Twelve of 15 MRSA isolates collected from the water had identical genetic characteristics as the organisms isolated from the participants exposed to that water while the remaining 3 MRSA were without matching nasal isolates from participants. The amount of S. aureus shed per person corresponded to 105 to 106 CFU per person per 15-minute bathing period, with 15 to 20% of this quantity testing positive for MRSA. Conclusions This is the first report of a comparison of human colonizing organisms with bacteria from human exposed marine water attempting to confirm that participants shed their own colonizing MSSA and MRSA into their bathing milieu. These findings clearly

  2. Temporal and stochastic control of Staphylococcus aureus biofilm development.

    Science.gov (United States)

    Moormeier, Derek E; Bose, Jeffrey L; Horswill, Alexander R; Bayles, Kenneth W

    2014-10-14

    Biofilm communities contain distinct microniches that result in metabolic heterogeneity and variability in gene expression. Previously, these niches were visualized within Staphylococcus aureus biofilms by observing differential expression of the cid and lrg operons during tower formation. In the present study, we examined early biofilm development and identified two new stages (designated "multiplication" and "exodus") that were associated with changes in matrix composition and a distinct reorganization of the cells as the biofilm matured. The initial attachment and multiplication stages were shown to be protease sensitive but independent of most cell surface-associated proteins. Interestingly, after 6 h of growth, an exodus of the biofilm population that followed the transition of the biofilm to DNase I sensitivity was demonstrated. Furthermore, disruption of the gene encoding staphylococcal nuclease (nuc) abrogated this exodus event, causing hyperproliferation of the biofilm and disrupting normal tower development. Immediately prior to the exodus event, S. aureus cells carrying a nuc::gfp promoter fusion demonstrated Sae-dependent expression but only in an apparently random subpopulation of cells. In contrast to the existing model for tower development in S. aureus, the results of this study suggest the presence of a Sae-controlled nuclease-mediated exodus of biofilm cells that is required for the development of tower structures. Furthermore, these studies indicate that the differential expression of nuc during biofilm development is subject to stochastic regulatory mechanisms that are independent of the formation of metabolic microniches. Importance: In this study, we provide a novel view of four early stages of biofilm formation by the human pathogen Staphylococcus aureus. We identified an initial nucleoprotein matrix during biofilm development that is DNase I insensitive until a critical point when a nuclease-mediated exodus of the population is induced prior

  3. Molecular and epidemiological analysis of methicillin-resistant Staphylococcus aureus otorrhoea: hospital- or community-acquired?

    Science.gov (United States)

    Nassif, R G; Soliman, R; Edwards, D H; Kara, N; Hussain, S S M

    2010-12-01

    (1) To identify newly diagnosed cases of methicillin-resistant Staphylococcus aureus ear infection in our local population; (2) to determine the risk factors involved in these patients' clinical courses, and (3) to type the bacterial strains isolated and thus identify whether they were hospital- or community-acquired. Retrospective review of case notes, together with laboratory-based molecular studies in the departments of otolaryngology and medical microbiology in a university teaching hospital in Scotland, UK. Over a two-year period, 35 patients were identified with ear swabs positive for methicillin-resistant Staphylococcus aureus infection. These cases came from both hospital and community settings. (1) Identification of primary methicillin-resistant Staphylococcus aureus otorrhoea in patients with no previously documented colonisation; and (2) molecular typing of the strains isolated, using spa technology, to identify whether they were hospital- or community-acquired. Of the 35 positive patients, 27 were previously known carriers of methicillin-resistant Staphylococcus aureus. The eight patients with newly diagnosed methicillin-resistant Staphylococcus aureus otorrhoea presented initially in the community. All of these patients had had contact with hospital staff (as in-patients or out-patients) in the weeks preceding development of their ear infection. Using the spa technique for molecular typing, we identified hospital-acquired ('epidemic') methicillin-resistant Staphylococcus aureus type 15 in all eight patients' isolates. All were sensitive to topical gentamicin. In our cohort, hospital-acquired methicillin-resistant Staphylococcus aureus type 15 was the commonest cause of methicillin-resistant Staphylococcus aureus otorrhoea, despite the fact that these patients all first presented in the community. We believe that contact with hospital staff or health care workers is a risk factor for acquiring methicillin-resistant Staphylococcus aureus otorrhoea in the

  4. Staphylococcus epidermidis ΔSortase A strain elicits protective immunity against Staphylococcus aureus infection.

    Science.gov (United States)

    Tan, Chao; Wang, Jun; Hu, Yifang; Wang, Peng; Zou, Lili

    2017-01-01

    Staphylococcus aureus and Staphylococcus epidermidis are two of the most significant opportunistic human pathogens, causing medical implant and nosocomial infections worldwide. These bacteria contain surface proteins that play crucial roles in multiple biological processes. It has become apparent that they have evolved a number of unique mechanisms by which they can immobilise proteins on their surface. Notably, a conserved cell membrane-anchored enzyme, sortase A (SrtA), can catalyse the covalent attachment of precursor bacterial cell wall-attached proteins to peptidoglycan. Considering its indispensable role in anchoring substrates to the cell wall and its effects on virulence, SrtA has attracted great attention. In this study, a 549-bp gene was cloned from a pathogenic S. epidermidis strain, YC-1, which shared high identity with srtA from other Staphylococcus spp. A mutant strain, YC-1ΔsrtA, was then constructed by allelic exchange mutagenesis. The direct survival rate assay suggested that YC-1ΔsrtA had a lower survival capacity in healthy mice blood compare with the wild-type strain, indicating that the deletion of srtA affects the virulence and infectious capacity of S. epidermidis YC-1. YC-1ΔsrtA was then administered via intraperitoneal injection and it provided a relative percent survival value of 72.7 % in mice against S. aureus TC-1 challenge. These findings demonstrate the possbility that YC-1ΔsrtA might be used as a live attenuated vaccine to produce cross-protection against S. aureus.

  5. Innovative approaches to treat Staphylococcus aureus biofilm-related infections.

    Science.gov (United States)

    Richter, Katharina; Van den Driessche, Freija; Coenye, Tom

    2017-02-28

    Many bacterial infections in humans and animals are caused by bacteria residing in biofilms, complex communities of attached organisms embedded in an extracellular matrix. One of the key properties of microorganisms residing in a biofilm is decreased susceptibility towards antimicrobial agents. This decreased susceptibility, together with conventional mechanisms leading to antimicrobial resistance, makes biofilm-related infections increasingly difficult to treat and alternative antibiofilm strategies are urgently required. In this review, we present three such strategies to combat biofilm-related infections with the important human pathogen Staphylococcus aureus: (i) targeting the bacterial communication system with quorum sensing (QS) inhibitors, (ii) a 'Trojan Horse' strategy to disturb iron metabolism by using gallium-based therapeutics and (iii) the use of 'non-antibiotics' with antibiofilm activity identified through screening of repurposing libraries. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

  6. Severe Staphylococcus aureus Endocarditis Presenting as Peripartum Thrombotic Thrombocytopenic Purpura.

    Science.gov (United States)

    Quinn, Kieran L; Osmond, Mark; Badiwala, Mitesh; Sermer, Mathew; Lapinsky, Stephen E

    2016-11-01

    Thrombotic thrombocytopenic purpura (TTP) is a life-threatening illness that occurs in both pregnant and non-pregnant women. Several other conditions can mimic the disease, which makes the diagnosis challenging. We describe a case of severe Staphylococcus aureus endocarditis that initially presented as peripartum TTP in a 39-year-old woman at 29+6 weeks' gestation. We give an overview of the diagnostic considerations and management of thrombocytopenia in pregnancy and review the literature related to TTP and peripartum infective endocarditis. Given the significant differences in definitive therapies for the spectrum of thrombocytopenic conditions that occur in pregnancy, timely and accurate diagnosis of TTP is critical for optimal management. Copyright © 2016 The Society of Obstetricians and Gynaecologists of Canada/La Société des obstétriciens et gynécologues du Canada. Published by Elsevier Inc. All rights reserved.

  7. Methicillin-resistant Staphylococcus aureus: a primer for dentists.

    Science.gov (United States)

    Klevens, R Monina; Gorwitz, Rachel J; Collins, Amy S

    2008-10-01

    In 2005 in the United States, an estimated 94,370 new, invasive infections and 18,650 deaths were associated with methicillin-resistant Staphylococcus aureus (MRSA); most of these infections were in people with exposures in health care settings. MRSA also has emerged as a community-based pathogen, causing primarily skin infections that are not life-threatening, but occasionally causing more severe and invasive infections. The authors describe the history of MRSA; identify populations at greatest risk of experiencing MRSA colonization and infection; compare characteristics of MRSA infections occurring in health care and community settings; and summarize strategies, based on U.S. Centers for Disease Control and Prevention recommendations and the literature, to prevent transmission of MRSA in dental offices. Standard infection control precautions should be enforced strictly in all ambulatory care settings, including dental offices, to prevent facility-based transmission of MRSA and other infectious agents.

  8. Quorum sensing inhibitors of Staphylococcus aureus from Italian medicinal plants.

    Science.gov (United States)

    Quave, Cassandra L; Plano, Lisa R W; Bennett, Bradley C

    2011-01-01

    Morbidity and mortality estimates due to methicillin-resistant Staphylococcus aureus (MRSA) infections continue to rise. Therapeutic options are limited by antibiotic resistance. Anti-pathogenic compounds, which inhibit quorum sensing (QS) pathways, may be a useful alternative to antibiotics. Staphylococcal QS is encoded by the AGR locus and is responsible for the production of δ-hemolysin. Quantification of δ-hemolysin found in culture supernatants permits the analysis of AGR activity at the translational rather than transcriptional level. We employed reversed phase high performance chromatographic (RP-HPLC) techniques to investigate the anti-QS activity of 168 extracts from 104 Italian plants through quantification of δ-hemolysin. Extracts from three medicinal plants (Ballota nigra, Castanea sativa, and Sambucus ebulus) exhibited a dose-dependent response in the production of δ-hemolysin, indicating anti-QS activity in a pathogenic MRSA isolate. © Georg Thieme Verlag KG Stuttgart · New York.

  9. Antimicrobial Photodynamic Therapy for Methicillin-Resistant Staphylococcus aureus Infection

    Directory of Open Access Journals (Sweden)

    Xiu-jun Fu

    2013-01-01

    Full Text Available Nowadays methicillin-resistant Staphylococcus aureus (MRSA is one of the most common multidrug resistant bacteria both in hospitals and in the community. In the last two decades, there has been growing concern about the increasing resistance to MRSA of the most potent antibiotic glycopeptides. MRSA infection poses a serious problem for physicians and their patients. Photosensitizer-mediated antimicrobial photodynamic therapy (PDT appears to be a promising and innovative approach for treating multidrug resistant infection. In spite of encouraging reports of the use of antimicrobial PDT to inactivate MRSA in large in vitro studies, there are only few in vivo studies. Therefore, applying PDT in the clinic for MRSA infection is still a long way off.

  10. Pseudomembranous colitis secondary to methicillin-resistant Staphylococcus aureus (MRSA).

    Science.gov (United States)

    Pressly, Kalynn B; Hill, Emilie; Shah, Kairav J

    2016-05-10

    A 37-year-old woman with a history of type II diabetes and Crohn's disease, status postcholecystectomy, presented with a >2-week history of cramping abdominal pain, nausea, non-bloody/non-bilious emesis and, later, diarrhoea. A flexible sigmoidoscopy was performed, revealing that 'a segmental pseudomembrane was found from rectum to sigmoid colon'. Clostridium difficile PCR on the stool was repeated twice and resulted negative both times. A food history prior to onset of symptoms was consistent with Staphylococcal food poisoning and a stool culture was positive for heavy growth of methicillin-resistant Staphylococcus aureus and the absence of enteric flora. The patient was successfully treated with oral vancomycin. 2016 BMJ Publishing Group Ltd.

  11. Purification, biochemical and kinetic properties of recombinant Staphylococcus aureus lipase.

    Science.gov (United States)

    Horchani, Habib; Fendri, Ahmed; Louati, Hanen; Sayari, Adel; Gargouri, Youssef; Verger, Robert

    2012-01-01

    We have compared the purification procedures as well as the biochemical and kinetic properties of wild type (wt-SAL3), untagged recombinant (rec(-His)SAL3), and tagged recombinant (rec(+His)SAL3) purified forms of Staphylococcus aureus lipase (SAL3). We used the pH-stat method (with emulsified tributyrin and olive oil as substrates) and the monomolecular film technique (with the three dicaprin isomers spread in the form of monomolecular films at the air-water interface). The data obtained showed that the recombinant expression process as well as the presence of a his-tag at the N-terminus of recombinant SAL3 affects significantly many biochemical and catalytic properties. The effects of the heterologous expression process on the catalytic properties of the staphylococcal lipases are three times more deleterious than the presence of an N-terminal tag extension.

  12. Staphylococcus aureus and the oxacillin sensitivity profile in hospitalized people with HIV/AIDS.

    Science.gov (United States)

    Pio, Daiana Patrícia Marchetti; Reinato, Lilian Andreia Fleck; Lopes, Letícia Pimenta; Gir, Elucir

    2016-01-01

    Analyze nasal colonization by oxacillin-sensitive and oxacillin-resistant Staphylococcus aureus in people with HIV/AIDS (PWHA) at days 1 and7 of hospitalization. A prospective observational study conducted in a hospital in the countryside of the state of São Paulo. Nasal swab samples were collected and analyzed through microbiological identification, at days 1 and 7 of hospitalization of PWHA, between August 2011 and January 2014. Data were analyzed via IBM SPSS(r), version 20.0. Nasal secretion samples were collected from 187 (50.1%) PWHA at days 1 and 7 of hospitalization. Of these, Staphylococcus aureus was identified in 64 (34.2%) PWHA. At day 1 of hospitalization, 27 PWHA were identified with Staphylococcus aureus; 27 PWHA presented colonization by Staphylococcus aureus at days 1 and 7, and 10 PWHA only at day 7. Of 64 PWHA colonized by Staphylococcus aureus, the susceptibility profile of isolated Staphylococcus aureus was oxacillin-resistant in 25 PWHA. Analisar a colonização nasal por Staphylococcus aureus sensíveis e resistentes à oxacilina de pessoas vivendo com HIV/aids (PVHA) no primeiro e no sétimo dia de internação hospitalar. Estudo prospectivo observacional realizado em um hospital do interior paulista. Foram coletadas e analisadas, por meio de identificação microbiológica, amostras de swab nasal no primeiro e no sétimo dia de internação hospitalar de PVHA, no período de agosto/2011 e janeiro/2014. A análise dos dados foi realizada por meio do IBM SPSS(r), versão 20.0. Em 187 (50,1%) PVHA foram coletadas amostras de secreção nasal no primeiro e sétimo dia de internação. Destas, em 64 (34,2%) foi identificado Staphylococcus aureus. No primeiro dia de internação observou-se 27 PVHA colonizadas por Staphylococcus aureus; em 27 PVHA houve a persistência da colonização por Staphylococcus aureus no primeiro e no sétimo dia; em 10 PVHA, somente no sétimo dia. Das 64 PVHA colonizadas por Staphylococcus aureus, em 25 o perfil de

  13. Phenazine antibiotic inspired discovery of potent bromophenazine antibacterial agents against Staphylococcus aureus and Staphylococcus epidermidis.

    Science.gov (United States)

    Borrero, Nicholas V; Bai, Fang; Perez, Cristian; Duong, Benjamin Q; Rocca, James R; Jin, Shouguang; Huigens, Robert W

    2014-02-14

    Nearly all clinically used antibiotics have been (1) discovered from microorganisms (2) using phenotype screens to identify inhibitors of bacterial growth. The effectiveness of these antibiotics is attributed to their endogenous roles as bacterial warfare agents against competing microorganisms. Unfortunately, every class of clinically used antibiotic has been met with drug resistant bacteria. In fact, the emergence of resistant bacterial infections coupled to the dismal pipeline of new antibacterial agents has resulted in a global health care crisis. There is an urgent need for innovative antibacterial strategies and treatment options to effectively combat drug resistant bacterial pathogens. Here, we describe the implementation of a Pseudomonas competition strategy, using redox-active phenazines, to identify novel antibacterial leads against Staphylococcus aureus and Staphylococcus epidermidis. In this report, we describe the chemical synthesis and evaluation of a diverse 27-membered phenazine library. Using this microbial warfare inspired approach, we have identified several bromophenazines with potent antibacterial activities against S. aureus and S. epidermidis. The most potent bromophenazine analogue from this focused library demonstrated a minimum inhibitory concentration (MIC) of 0.78-1.56 μM, or 0.31-0.62 μg mL(-1), against S. aureus and S. epidermidis and proved to be 32- to 64-fold more potent than the phenazine antibiotic pyocyanin in head-to-head MIC experiments. In addition to the discovery of potent antibacterial agents against S. aureus and S. epidermidis, we also report a detailed structure-activity relationship for this class of bromophenazine small molecules.

  14. Electron Microscopy of Staphylococcus aureus Cell Wall Lysis

    Science.gov (United States)

    Virgilio, R.; González, C.; Muñoz, Nubia; Mendoza, Silvia

    1966-01-01

    Virgilio, Rafael (Escuela de Química y Farmacia, Universidad de Chile, Santiago, Chile), C. González, Nubia Muñoz, and Silvia Mendoza. Electron microscopy of Staphylococcus aureus cell wall lysis. J. Bacteriol. 91:2018–2024. 1966.—A crude suspension of Staphylococcus aureus cell walls (strain Cowan III) in buffer solution was shown by electron microscopy to lyse slightly after 16 hr, probably owing to the action of autolysin. The lysis was considerably faster and more intense after the addition of lysozyme. A remarkable reduction in thickness and rigidity of the cell walls, together with the appearance of many irregular protrusions in their outlines, was observed after 2 hr; after 16 hr, there remained only a few recognizable cell wall fragments but many residual particulate remnants. When autolysin was previously inactivated by trypsin, there was a complete inhibition of the lytic action of lysozyme; on the other hand, when autolysin was inactivated by heat and lysozyme was added, a distinct decrease in the thickness of the cell walls was observed, but there was no destruction of the walls. The lytic action of lysozyme, after treatment with hot 5% trichloroacetic acid, gave rise to a marked dissolution of the structure of the cell walls, which became lost against the background, without, however, showing ostensible alteration of wall outlines. From a morphological point of view, the lytic action of autolysin plus lysozyme was quite different from that of trichloroacetic acid plus lysozyme, as shown by electron micrographs, but in both cases it was very intense. This would suggest different mechanisms of action for these agents. Images PMID:5939482

  15. Staphylococcus aureus infections: transmission within households and the community.

    Science.gov (United States)

    Knox, Justin; Uhlemann, Anne-Catrin; Lowy, Franklin D

    2015-07-01

    Staphylococcus aureus, both methicillin susceptible and resistant, are now major community-based pathogens worldwide. The basis for this is multifactorial and includes the emergence of epidemic clones with enhanced virulence, antibiotic resistance, colonization potential, or transmissibility. Household reservoirs of these unique strains are crucial to their success as community-based pathogens. Staphylococci become resident in households, either as colonizers or environmental contaminants, increasing the risk for recurrent infections. Interactions of household members with others in different households or at community sites, including schools and daycare facilities, have a critical role in the ability of these strains to become endemic. Colonization density at these sites appears to have an important role in facilitating transmission. The integration of research tools, including whole-genome sequencing (WGS), mathematical modeling, and social network analysis, has provided additional insight into the transmission dynamics of these strains. Thus far, interventions designed to reduce recurrent infections among household members have had limited success, likely due to the multiplicity of potential sources for recolonization. The development of better strategies to reduce the number of household-based infections will depend on greater insight into the different factors that contribute to the success of these uniquely successful epidemic clones of S. aureus. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Characterization of transcription within sdr region of Staphylococcus aureus.

    Science.gov (United States)

    Sitkiewicz, Izabela; Babiak, Ireneusz; Hryniewicz, Waleria

    2011-02-01

    Staphylococcus aureus is an opportunistic pathogen responsible for various infections in humans and animals. It causes localized and systemic infections, such as abscesses, impetigo, cellulitis, sepsis, endocarditis, bone infections, and meningitis. S. aureus virulence factors responsible for the initial contact with host cells (MSCRAMMs-microbial surface components recognizing adhesive matrix molecules) include three Sdr proteins. The presence of particular sdr genes is correlated with putative tissue specificity. The transcriptional organization of the sdr region remains unclear. We tested expression of the sdrC, sdrD, or sdrE genes in various in vitro conditions, as well as after contact with human blood. In this work, we present data suggesting a separation of the sdr region into three transcriptional units, based on their differential reactions to the environment. Differential reaction of the sdrD transcript to environmental conditions and blood suggests dissimilar functions of the sdr genes. SdrE has been previously proposed to play role in bone infections, whilst our results can indicate that sdrD plays a role in the interactions between the pathogen and human immune system, serum or specifically reacts to nutrients/other factors present in human blood.

  17. Expression of Four Methionine Sulfoxide Reductases in Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Kuldeep Singh

    2012-01-01

    Full Text Available Staphylococcus aureus possesses three MsrA enzymes (MsrA1, MsrA2, MsrA3 that reduce the S-epimer of methionine sulfoxide (MetO and an MsrB enzyme that reduces R-MetO. The four msr genes are expressed from three different promoters. The msrA1/msrB genes are coexpressed. To determine the expression pattern of msr genes, three independent reporter strains were constructed where msr promoter was cloned in front of a promoterless lacZ and the resulting construct was integrated in the chromosome. Using these strains, it was determined that the msrA1/B expression is significantly higher in S. aureus compared to msrA2 or msrA3. Expression of msrA1/B was highest during stationary phase growth, but the expression of msrA2 and msrA3 was highest during the early to midexponential growth phase. Expression of msrA1/B was induced by oxacillin and the expression of msrA3 was upregulated by salt. Expression of msrA2 remained unchanged under all tested conditions.

  18. Antimicrobial activity of essential oils against Staphylococcus aureus biofilms.

    Science.gov (United States)

    Vázquez-Sánchez, Daniel; Cabo, Marta L; Rodríguez-Herrera, Juan J

    2015-12-01

    The present study was aimed to evaluate the potential of essential oils to remove the foodborne pathogen Staphylococcus aureus from food-processing facilities. The effectiveness of 19 essential oils against planktonic cells of S. aureus was firstly assessed by minimal inhibitory concentration. Planktonic cells showed a wide variability in resistance to essential oils, with thyme oil as the most effective, followed by lemongrass oil and then vetiver oil. The eight essential oils most effective against planktonic cells were subsequently tested against 48-h-old biofilms formed on stainless steel. All essential oils reduced significantly (p oils were the most effective, but high concentrations were needed to achieve logarithmic reductions over 4 log CFU/cm(2) after 30 min exposure. Alternatively, the use of sub-lethal doses of thyme oil allowed to slow down biofilm formation and to enhance the efficiency of thyme oil and benzalkonium chloride against biofilms. However, some cellular adaptation to thyme oil was detected. Therefore, essential oil-based treatments should be based on the rotation and combination of different essential oils or with other biocides to prevent the emergence of antimicrobial-resistant strains. © The Author(s) 2014.

  19. METHICILLIN - RESISTANT STAPHYLOCOCCUS AUREUS IN PIG PRODUCTION CHAIN

    Directory of Open Access Journals (Sweden)

    M. Conter

    2012-08-01

    Full Text Available The aims of this study were (i to estimate the prevalence of Staphylococcus aureus (S.a in pig farm environments; (ii to evaluate the presence of S.a in pork processing environments (iii to detect the presence of methicillin-resistant (MRSA among isolated strains. Samples of pig stool, farm environment and pork processing environment were collected. These samples were submitted to detection of S.a following the international method: UNI EN ISO 6888-2 and the Minimum Inhibitory Concentrations (MIC tests were performed by using the automated VITEK 2 system. In addition, a PCR for the detection of the mecA gene was applied. Overall, S. aureus were more frequently detected from pig farms than from pork processing environments. Among the n.51 isolated strains, n. 49 (96% were methicillin resistant (MRSA and only n.2 strains were methicillin sensitive (MSSA. The results of the present study highlighted that further studies are needed to elucidate transmission routes of MRSA in pig production chain.

  20. Glucose Augments Killing Efficiency of Daptomycin Challenged Staphylococcus aureus Persisters.

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    Marcel Prax

    Full Text Available Treatment of Staphylococcus aureus in stationary growth phase with high doses of the antibiotic daptomycin (DAP eradicates the vast majority of the culture and leaves persister cells behind. Despite resting in a drug-tolerant and dormant state, persister cells exhibit metabolic activity which might be exploited for their elimination. We here report that the addition of glucose to S. aureus persisters treated with DAP increased killing by up to five-fold within one hour. This glucose-DAP effect also occurred with strains less sensitive to the drug. The underlying mechanism is independent of the proton motive force and was not observed with non-metabolizable 2-deoxy-glucose. Our results are consistent with two hypotheses on the glucose-DAP interplay. The first is based upon glucose-induced carbohydrate transport proteins that may influence DAP and the second suggests that glucose may trigger the release or activity of cell-lytic proteins to augment DAP's mode of action.

  1. Adhesion force of staphylococcus aureus on various biomaterial surfaces.

    Science.gov (United States)

    Alam, Fahad; Balani, Kantesh

    2017-01-01

    Staphylococcus comprises of more than half of all pathogens in orthopedic implant infections and they can cause major bone infection which can result in destruction of joint and bone. In the current study, adhesion force of bacteria on the surface of various biomaterial surfaces is measured using atomic force microscope (AFM). Staphylococcus aureus was immobilized on an AFM tipless cantilever as a force probe to measure the adhesion force between bacteria and biomaterials (viz. ultra-high molecular weight poly ethylene (UHMWPE), stainless steel (SS), Ti-6Al-4V alloy, hydroxyapatite (HA)). At the contact time of 10s, UHMWPE shows weak adhesion force (~4nN) whereas SS showed strong adhesion force (~15nN) due to their surface energy and surface roughness. Bacterial retention and viability experiment (3M™ petrifilm test, agar plate) dictates that hydroxyapatite shows the lowest vaibility of bacteria, whereas lowest bacterial retention is observed on UHMWPE surface. Similar results were obtained from live/dead staining test, where HA shows 65% viability, whereas on UHMWPE, SS and Ti-6Al-4V, the bacterial viability is 78%, 94% and 97%, respectively. Lower adhesion forces, constrained pull-off distance (of bacterial) and high antibacterial resistance of bioactive-HA makes it a potential biomaterial for bone-replacement arthroplasty. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Pesquisa de Staphylococcus aureus em leite a ser pasteurizado Staphylococcus aureus in milk before pasteurinzing

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    Donald Wilson

    1977-03-01

    Full Text Available Estuda-se a contaminação por S. aureus do leite a ser pasteurizado, demonstrando que está altamente contaminado. São discutidas as conseqüências que a contaminação pode ter e conclui-se serem necessárias medidas urgentes para alterar a estrutura epidemiológica da "linha de leite".The present paper is a study on Staphylococcal contamination of milk before pasteurizing. Gross contamination is shown, and possible consequences are discussed. That measures intended to alter the epidemiologic structure of the so called milk line are necessary and urgent, is the final conclusion of the paper.

  3. The Staphylococcus aureus FASII bypass escape route from FASII inhibitors.

    Science.gov (United States)

    Morvan, Claire; Halpern, David; Kénanian, Gérald; Pathania, Amit; Anba-Mondoloni, Jamila; Lamberet, Gilles; Gruss, Alexandra; Gloux, Karine

    2017-10-01

    Antimicrobials targeting the fatty acid synthesis (FASII) pathway are being developed as alternative treatments for bacterial infections. Emergence of resistance to FASII inhibitors was mainly considered as a consequence of mutations in the FASII target genes. However, an alternative and efficient anti-FASII resistance strategy, called here FASII bypass, was uncovered. Bacteria that bypass FASII incorporate exogenous fatty acids in membrane lipids, and thus dispense with the need for FASII. This strategy is used by numerous Gram-positive low GC % bacteria, including streptococci, enterococci, and staphylococci. Some bacteria repress FASII genes once fatty acids are available, and "constitutively" shift to FASII bypass. Others, such as the major pathogen Staphylococcus aureus, can undergo high frequency mutations that favor FASII bypass. This capacity is particularly relevant during infection, as the host supplies the fatty acids needed for bacteria to bypass FASII and thus become resistant to FASII inhibitors. Screenings for anti-FASII resistance in the presence of exogenous fatty acids confirmed that FASII bypass confers anti-FASII resistance among clinical and veterinary isolates. Polymorphisms in S. aureus FASII initiation enzymes favor FASII bypass, possibly by increasing availability of acyl-carrier protein, a required intermediate. Here we review FASII bypass and consequences in light of proposed uses of anti-FASII to treat infections, with a focus on FASII bypass in S. aureus. Copyright © 2017 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

  4. Methicillin-resistant Staphylococcus aureus: a new zoonotic agent?

    Science.gov (United States)

    Springer, Burkhard; Orendi, Ulrike; Much, Peter; Höger, Gerda; Ruppitsch, Werner; Krziwanek, Karina; Metz-Gercek, Sigrid; Mittermayer, Helmut

    2009-01-01

    Staphylococcus aureus is a major cause of infection in hospitals and the community. One third of the general population is colonized by the bacterium, constituting a risk factor for acquisition of infection with this pathogen. Worldwide, the increasing antibiotic resistance of S. aureus complicates treatment of infection and control measures. Soon after the introduction of methicillin, the first isolates resistant to this antibiotic were reported and named methicillin-resistant S. aureus (MRSA). During the past decade a major change in MRSA epidemiology has been observed: whereas in the past MRSA was almost exclusively regarded a hospital pathogen, the advent of community-acquired MRSA has led to infections in people without hospital-related risk factors. Recent evidence has also identified a link between colonization of livestock and MRSA carriage and infections in people who work with animals. Screening of pigs and pig farmers in the Netherlands revealed high prevalence of MRSA sequence type (ST) 398 and it has become clear that the emergence of ST398 is not just a Dutch problem, as reports on livestock colonization and human infections are appearing worldwide. In Austria, the ST398 lineage has been detected in dust samples from pig breeding facilities and in food samples. Since the first Austrian detection of this emerging lineage in 2006, 21 human isolates, partially associated with infections, have been observed. MRSA has to be regarded as a new emerging zoonotic agent and livestock may constitute a growing reservoir of the ST398 lineage. More information is needed so that control measures to reduce the impact of the emerging MRSA ST398 lineage on public health can be developed and implemented.

  5. Repurposing salicylanilide anthelmintic drugs to combat drug resistant Staphylococcus aureus.

    Science.gov (United States)

    Rajamuthiah, Rajmohan; Fuchs, Beth Burgwyn; Conery, Annie L; Kim, Wooseong; Jayamani, Elamparithi; Kwon, Bumsup; Ausubel, Frederick M; Mylonakis, Eleftherios

    2015-01-01

    Staphylococcus aureus is a Gram-positive bacterium that has become the leading cause of hospital acquired infections in the US. Repurposing Food and Drug Administration (FDA) approved drugs for antimicrobial therapy involves lower risks and costs compared to de novo development of novel antimicrobial agents. In this study, we examined the antimicrobial properties of two commercially available anthelmintic drugs. The FDA approved drug niclosamide and the veterinary drug oxyclozanide displayed strong in vivo and in vitro activity against methicillin resistant S. aureus (minimum inhibitory concentration (MIC): 0.125 and 0.5 μg/ml respectively; minimum effective concentration: ≤ 0.78 μg/ml for both drugs). The two drugs were also effective against another Gram-positive bacteria Enterococcus faecium (MIC 0.25 and 2 μg/ml respectively), but not against the Gram-negative species Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter aerogenes. The in vitro antimicrobial activity of niclosamide and oxyclozanide were determined against methicillin, vancomycin, linezolid or daptomycin resistant S. aureus clinical isolates, with MICs at 0.0625-0.5 and 0.125-2 μg/ml for niclosamide and oxyclozanide respectively. A time-kill study demonstrated that niclosamide is bacteriostatic, whereas oxyclozanide is bactericidal. Interestingly, oxyclozanide permeabilized the bacterial membrane but neither of the anthelmintic drugs exhibited demonstrable toxicity to sheep erythrocytes. Oxyclozanide was non-toxic to HepG2 human liver carcinoma cells within the range of its in vitro MICs but niclosamide displayed toxicity even at low concentrations. These data show that the salicylanilide anthelmintic drugs niclosamide and oxyclozanide are suitable candidates for mechanism of action studies and further clinical evaluation for treatment of staphylococcal infections.

  6. Repurposing salicylanilide anthelmintic drugs to combat drug resistant Staphylococcus aureus.

    Directory of Open Access Journals (Sweden)

    Rajmohan Rajamuthiah

    Full Text Available Staphylococcus aureus is a Gram-positive bacterium that has become the leading cause of hospital acquired infections in the US. Repurposing Food and Drug Administration (FDA approved drugs for antimicrobial therapy involves lower risks and costs compared to de novo development of novel antimicrobial agents. In this study, we examined the antimicrobial properties of two commercially available anthelmintic drugs. The FDA approved drug niclosamide and the veterinary drug oxyclozanide displayed strong in vivo and in vitro activity against methicillin resistant S. aureus (minimum inhibitory concentration (MIC: 0.125 and 0.5 μg/ml respectively; minimum effective concentration: ≤ 0.78 μg/ml for both drugs. The two drugs were also effective against another Gram-positive bacteria Enterococcus faecium (MIC 0.25 and 2 μg/ml respectively, but not against the Gram-negative species Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter aerogenes. The in vitro antimicrobial activity of niclosamide and oxyclozanide were determined against methicillin, vancomycin, linezolid or daptomycin resistant S. aureus clinical isolates, with MICs at 0.0625-0.5 and 0.125-2 μg/ml for niclosamide and oxyclozanide respectively. A time-kill study demonstrated that niclosamide is bacteriostatic, whereas oxyclozanide is bactericidal. Interestingly, oxyclozanide permeabilized the bacterial membrane but neither of the anthelmintic drugs exhibited demonstrable toxicity to sheep erythrocytes. Oxyclozanide was non-toxic to HepG2 human liver carcinoma cells within the range of its in vitro MICs but niclosamide displayed toxicity even at low concentrations. These data show that the salicylanilide anthelmintic drugs niclosamide and oxyclozanide are suitable candidates for mechanism of action studies and further clinical evaluation for treatment of staphylococcal infections.

  7. [Repair mechanism of frozen sublethally damaged Staphylococcus aureus].

    Science.gov (United States)

    Huang, Zhongmin; Lv, Haipeng; Ai, Zhilu; Wang, Na; Xie, Xinhua; Fan, Huiping; Pan, Zhili; Suo, Biao

    2015-11-04

    To study the repair mechanisms of frozen sublethally damaged Staphylococcus aurous cells. We resuscitated frozen sublethally damaged S. aureus at 37 degrees C for different time within 3 h. Meanwhile, we compared the morphological changes of the frozen sublethally damaged cells after 1 h of resuscitation using transmission electron microscopy assay (TEM). The expressions of the transcriptional attenuator MsrR (msrR), iron (Fe3+) ABC transporter ATP-binding protein (fhuC), and cytochrome b (cytB) genes were quantitatively analyzed by real-time fluorescence quantitative PCR (Real-time PCR) method. The content of cells outside leakage, active oxygen (ROS), and superoxide dismutase (SOD) activity were also determined by ultraviolet spectrophotometry. More than 99% of the frozen sublethally damaged S. aureus repaired after 3 h. The resuscitated cells expressed an equal resistance to high concentration of NaCl. Real-time PCR results showed that the msrR and fhuC genes expressions were down-regulated, whereas the cytB gene expression was up-regulated significantly. The frozen sublethally damaged S. aureus cellar surface ultrastructure significant changed during resuscitation. The cell surface became compact and sturdy from smooth and transparent. The cell leakage rate of ultraviolet absorption material gradually decreased. Meanwhile, the intracellular ROS level declined along with the decrease of SOD activity. Frozen sublethally damaged cells may regain the capability of resistance to high salt stress by repairing cell membrane integrity, reducing the content of ROS through gene regulation, inhibiting the toxicity of active oxygen to the cells. Meanwhile, the regulation of metabolism related genes (cytB) provides the energy for the requirement of cells, therefore, the frozen sublethally damaged cells were repaired finally.

  8. Staphylococcus aureus α-Toxin: Nearly a Century of Intrigue

    Directory of Open Access Journals (Sweden)

    Bryan J. Berube

    2013-06-01

    Full Text Available Staphylococcus aureus secretes a number of host-injurious toxins, among the most prominent of which is the small β-barrel pore-forming toxin α-hemolysin. Initially named based on its properties as a red blood cell lytic toxin, early studies suggested a far greater complexity of α-hemolysin action as nucleated cells also exhibited distinct responses to intoxication. The hemolysin, most aptly referred to as α-toxin based on its broad range of cellular specificity, has long been recognized as an important cause of injury in the context of both skin necrosis and lethal infection. The recent identification of ADAM10 as a cellular receptor for α-toxin has provided keen insight on the biology of toxin action during disease pathogenesis, demonstrating the molecular mechanisms by which the toxin causes tissue barrier disruption at host interfaces lined by epithelial or endothelial cells. This review highlights both the historical studies that laid the groundwork for nearly a century of research on α-toxin and key findings on the structural and functional biology of the toxin, in addition to discussing emerging observations that have significantly expanded our understanding of this toxin in S. aureus disease. The identification of ADAM10 as a proteinaceous receptor for the toxin not only provides a greater appreciation of truths uncovered by many historic studies, but now affords the opportunity to more extensively probe and understand the role of α-toxin in modulation of the complex interaction of S. aureus with its human host.

  9. Staphylococcus aureus α-Toxin: Nearly a Century of Intrigue

    Science.gov (United States)

    Berube, Bryan J.; Bubeck Wardenburg, Juliane

    2013-01-01

    Staphylococcus aureus secretes a number of host-injurious toxins, among the most prominent of which is the small β-barrel pore-forming toxin α-hemolysin. Initially named based on its properties as a red blood cell lytic toxin, early studies suggested a far greater complexity of α-hemolysin action as nucleated cells also exhibited distinct responses to intoxication. The hemolysin, most aptly referred to as α-toxin based on its broad range of cellular specificity, has long been recognized as an important cause of injury in the context of both skin necrosis and lethal infection. The recent identification of ADAM10 as a cellular receptor for α-toxin has provided keen insight on the biology of toxin action during disease pathogenesis, demonstrating the molecular mechanisms by which the toxin causes tissue barrier disruption at host interfaces lined by epithelial or endothelial cells. This review highlights both the historical studies that laid the groundwork for nearly a century of research on α-toxin and key findings on the structural and functional biology of the toxin, in addition to discussing emerging observations that have significantly expanded our understanding of this toxin in S. aureus disease. The identification of ADAM10 as a proteinaceous receptor for the toxin not only provides a greater appreciation of truths uncovered by many historic studies, but now affords the opportunity to more extensively probe and understand the role of α-toxin in modulation of the complex interaction of S. aureus with its human host. PMID:23888516

  10. Ultrastructural Study on the Antibacterial Activity of Artonin E versus Streptomycin against Staphylococcus aureus Strains.

    Directory of Open Access Journals (Sweden)

    Asdren Zajmi

    Full Text Available Staphylococci are facultative anaerobes, perfectly spherical un-encapsulated cocci, with a diameter not exceeding 1 micrometer in diameter. Staphylococcus aureus are generally harmless and remain confined to the skin unless they burrow deep into the body, causing life-threatening infections in bones, joints, bloodstream, heart valves and lungs. Among the 20 medically important staphylococci species, Staphylococcus aureus is one of the emerging human pathogens. Streptomycin had its highest potency against Staphylococcus infections despite the likelihood of getting a resistant type of staphylococcus strains. Methicillin-resistant S. aureus (MRSA is the persister type of Staphylococcus aureus and was evolved after decades of antibiotic misuse. Inadequate penetration of the antibiotic is one of the principal factors related to success/failure of the therapy. The active drug needs to reach the bacteria at concentrations necessary to kill or suppress the pathogen's growth. In turn the effectiveness of the treatment relied on the physical properties of Staphylococcus aureus. Thus understanding the cell integrity, shape and roughness is crucial to the overall influence of the therapeutic agent on S. aureus of different origins. Hence our experiments were designed to clarify ultrastructural changes of S. aureus treated with streptomycin (synthetic compound in comparison to artonin E (natural compound. In addition to the standard in vitro microbial techniques, we used transmission electron microscopy to study the disrupted cell architecture under antibacterial regimen and we correlate this with scanning electron microscopy (SEM to compare results of both techniques.

  11. Antibiotic-mediated selection of quorum-sensing-negative Staphylococcus aureus

    DEFF Research Database (Denmark)

    Paulander, Wilhelm Erik Axel; Varming, Anders Nissen; Bæk, Kristoffer Torbjørn

    2012-01-01

    -acquired S. aureus infections and suggest that the adaptability of S. aureus to antibiotics involves the agr locus. IMPORTANCE: Staphylococcus aureus is the most frequently isolated pathogen in intensive care units and a common cause of nosocomial infections, resulting in a high degree of morbidity......Staphylococcus aureus is a human commensal that at times turns into a serious bacterial pathogen causing life-threatening infections. For the delicate control of virulence, S. aureus employs the agr quorum-sensing system that, via the intracellular effector molecule RNAIII, regulates virulence gene...... increases the agr-mediated fitness cost by inducing the expression of RNAIII. Thus, the extensive use of antibiotics in hospitals may explain why agr-negative variants are frequently isolated from hospital-acquired S. aureus infections but rarely found among community-acquired S. aureus strains. Importantly...

  12. Genomic analysis of an emerging multiresistant Staphylococcus aureus strain rapidly spreading in cystic fibrosis patients revealed the presence of an antibiotic inducible bacteriophage

    Directory of Open Access Journals (Sweden)

    Boniface Stephanie

    2009-01-01

    Full Text Available Abstract Background Staphylococcus aureus is a major human pathogen responsible for a variety of nosocomial and community-acquired infections. Recent reports show that the prevalence of Methicillin-Resistant S. aureus (MRSA infections in cystic fibrosis (CF patients is increasing. In 2006 in Marseille, France, we have detected an atypical MRSA strain with a specific antibiotic susceptibility profile and a unique growth phenotype. Because of the clinical importance of the spread of such strain among CF patients we decided to sequence the genome of one representative isolate (strain CF-Marseille to compare this to the published genome sequences. We also conducted a retrospective epidemiological analysis on all S. aureus isolated from 2002 to 2007 in CF patients from our institution. Results CF-Marseille is multidrug resistant, has a hetero-Glycopeptide-Intermediate resistance S. aureus phenotype, grows on Cepacia agar with intense orange pigmentation and has a thickened cell wall. Phylogenetic analyses using Complete Genome Hybridization and Multi Locus VNTR Assay showed that CF-Marseille was closely related to strain Mu50, representing vancomycin-resistant S. aureus. Analysis of CF-Marseille shows a similar core genome to that of previously sequenced MRSA strains but with a different genomic organization due to the presence of specific mobile genetic elements i.e. a new SCCmec type IV mosaic cassette that has integrated the pUB110 plasmid, and a new phage closely related to phiETA3. Moreover this phage could be seen by electron microscopy when mobilized with several antibiotics commonly used in CF patients including, tobramycin, ciprofloxacin, cotrimoxazole, or imipenem. Phylogenetic analysis of phenotypically similar h-GISA in our study also suggests that CF patients are colonized by polyclonal populations of MRSA that represents an incredible reservoir for lateral gene transfer. Conclusion In conclusion, we demonstrated the emergence and

  13. Nasal Carriage Rate of Methicillin Resistant Staphylococcus aureus among Health Care Workers at a Tertiary Care Hospital in Kathmandu, Nepal.

    Science.gov (United States)

    Khatri, S; Pant, N D; Bhandari, R; Shrestha, K L; Shrestha, C D; Adhikari, N; Poudel, A

    2017-01-01

    Methicillin-resistant Staphylococcus aureus is one of the most common causes of nosocomial infections. Due to its multidrug resistant nature; infections due to Methicillin-resistant Staphylococcus aureus are often very difficult to treat. Colonized health care workers are the important sources of Methicillin-resistant Staphylococcus aureus. The objectives of this study were to determine the nasal carriage rate of Methicillin-resistant Staphylococcus aureus among health care workers at Kathmandu Medical College and Teaching Hospital, Nepal and to assess their antimicrobial susceptibility patterns. A cross sectional study was conducted among 252 health care workers from July to November 2013. Mannitol salt agar was used to culture the nasal swabs. Antimicrobial susceptibility testing was performed by Kirby-Bauer disc diffusion technique following Clinical and Laboratory Standards Institute guidelines. Methicillin-resistant Staphylococcus aureus strains were confirmed by using cefoxitin disc and by determining the minimum inhibitory concentration of oxacillin by agar dilution method. Of 252 healthcare workers, 46(18.3%) were positive for Staphylococcus aureus among which 19(41.3%) were Methicillin-resistant Staphylococcus aureus carriers. Overall rate of nasal carriage of Methicillin-resistant Staphylococcus aureus was 7.5% (19/252).The higher percentages of lab personnel were nasal carriers of S. aureus (31.6%) and Methicillin-resistant Staphylococcus aureus (10.5%).The percentages of nasal carriage of S. aureus (35.7%) and Methicillin-resistant Staphylococcus aureus (14.3%) were highest in the health care workers from post operative department. Higher percentage of Methicillin-resistant Staphylococcus aureus were susceptible toward amikacin (100%) and vancomycin (100%) followed by cotrimoxazole (84.2%). High rates of nasal carriage of S. aureus and Methicillin-resistant Staphylococcus aureus were observed among the healthcare workers, which indicate the need of

  14. Occurrence and antimicrobial resistance of Staphylococcus aureus in bulk tank milk and milk filters

    Directory of Open Access Journals (Sweden)

    Kateřina Bogdanovičová

    2014-02-01

    Full Text Available This work is focused on the monitoring of Staphylococcus aureus prevalence in raw milk and milk filters, its antibiotic resistance and detection of methicillin resistant Staphylococcus aureus (MRSA. Samples of raw cow´s milk and milk filters were collected in the period from 2012 till 2014, from 50 dairy farms in the Czech Republic. The total of 261 samples (164 samples of raw milk and 97 milk filters were cultivated on Baird-Parker agar. Both the typical and atypical colonies were examined by plasmacoagulase test and PCR method was used for detection of species specific fragment SA442 and mecA gene. Standard disk diffusion method was used to determinate resistance to antimicrobial agents. The bacterium Staphylococcus aureus was detected on 25 farms (50%. The antimicrobial resistance showed differences between the farms. Total of 58 samples were positive for Staphylococcus aureus, of which were 37 (14.2% isolated from raw milk samples and 21 (8.1% from milk filters. From these samples we isolated 62 Staphylococcus aureus strains, 41 isolates bacteria S. aureus from raw milk (66.1% and 21 isolates S. aureus from milk filters (33.9%. The presence of antibiotic resistance in Staphylococcus aureus isolates was low, most of them were resistant to amoxicilin. According to the results obtained by the PCR method for the methicillin - resistant S. aureus (MRSA, the mecA gene was present in 6 strains (9.7%, 4 isolates obtained from milk samples (6.5% and 2 isolates from milk filters (3.2%.  These isolates can be considered as a possible source of resistance genes, which can be spread through the food chain. Nowadays, a globally unfavourable increasing trend of prevalence of methicillin resistant staphylococci strains especially Staphylococcus aureus is being observed worldwide. The improper hygiene and poor farm management practices contributed to the presence of S. aureus in the milk. This may have contributed to the high level of S. aureus isolated

  15. Ethanol and Isopropyl Alcohol Exposure Increases Biofilm Formation in Staphylococcus aureus and Staphylococcus epidermidis.

    Science.gov (United States)

    Luther, Megan K; Bilida, Sarah; Mermel, Leonard A; LaPlante, Kerry L

    2015-06-01

    Alcohols, including ethanol and isopropyl alcohol, are used in clinical practice for disinfection and infection prevention. Recent studies, however, demonstrate that alcohols may enhance biofilm production in Staphylococci. We quantified biofilm formation in the presence of ethanol and isopropyl alcohol in six different, well-characterized strains of Staphylococcus epidermidis and Staphylococcus aureus. After 24 h of biofilm development, each strain was exposed to normal saline (NS), ethanol, or isopropyl alcohol (40%, 60%, 80% and 95%) for additional 24 h incubation. Adherent biofilms were stained and optical density was determined. Viability of strains was also determined after alcohol exposure. Ethanol increased biofilm formation in all six strains compared to normal saline (p alcohol also increased biofilm formation with increasing alcohol concentration in all six strains (p alcohols, likely reverting back its primary phenotype through modulation of the intercellular adhesin repressor. All strains demonstrated viability after exposure to each alcohol concentration, though viability was decreased. Ethanol and isopropyl alcohol exposure increases biofilm formation of S. aureus and S. epidermidis at concentrations used in clinical settings. Ethanol and isopropyl alcohol did not eradicate viable Staphylococci from formed biofilm.

  16. Clinical significance of Staphylococcus aureus bacteriuria in a nationwide study of adults with S. aureus bacteraemia.

    Science.gov (United States)

    Asgeirsson, Hilmir; Kristjansson, Mar; Kristinsson, Karl G; Gudlaugsson, Olafur

    2012-01-01

    To evaluate the clinical significance of Staphylococcus aureus bacteriuria (SABU) in adults with S. aureus bacteraemia (SAB). All individuals ≥18 years old diagnosed with SAB in Iceland between December 1st 2003 and November 30th 2008 were retrospectively identified. Data was collected from medical records. Concomitant SABU was defined as growth of S. aureus in a urine sample taken within 24 h of the index blood culture. SABU was seen in 27 of 166 (16.3%) SAB patients having urine cultured before administration of antibiotics, but after excluding those with SAB of urinary tract origin SABU was seen in 16 of 152 (10.5%). In this latter cohort SABU was independently associated with having endocarditis (RR 6.68; 95% CI 1.53-17.3) and admission to intensive-care unit (RR 2.84; 95% CI 1.25-4.44), while for having complicated SAB the RR was 1.56 (95% CI 0.96-1.80). No correlation was seen with mortality or relapse rates. SABU appears to be secondary to SAB in some cases while it is the primary infection causing SAB in others. In patients with SAB of non-urinary tract origin SABU should probably be regarded as distant haematogenous seeding and a marker of deep tissue dissemination, thus affecting general management and treatment duration. Copyright © 2011 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

  17. Nasopharyngeal co-colonization with Staphylococcus aureus and Streptococcus pneumoniae in children is bacterial genotype independent.

    NARCIS (Netherlands)

    Melles, D.C.; Bogaert, D.; Gorkink, R.F.; Peeters, J.K.; Moorhouse, M.J.; Ott, A.; Leeuwen, W.B. van; Simons, G.; Verbrugh, H.A.; Hermans, P.W.M.; Belkum, A. van

    2007-01-01

    Bacterial interference between Staphylococcus aureus and Streptococcus pneumoniae in the nasopharynx has been observed during colonization, which might have important clinical implications for the widespread use of pneumococcal conjugate vaccine in young children. This study aimed to determine

  18. Evaluation of fusidic acid in therapy of experimental Staphylococcus aureus meningitis

    DEFF Research Database (Denmark)

    Østergaard, Christian; Yieng-Kow, Runa Vavia; Knudsen, Jenny Dahl

    2003-01-01

    Combination therapy that includes fusidic acid, an antimicrobial agent highly active against staphylococci, has been recommended in the treatment of patients with Staphylococcus aureus meningitis. The aim of this study was to evaluate the pharmacokinetic, CSF bactericidal and anti...

  19. The Lytic SA Phage Demonstrate Bactericidal Activity against Mastitis Causing Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Hamza Ameer

    2016-01-01

    Full Text Available Staphylococcus aureus is the major causative agent of mastitis among dairy animals as it causes intramammary gland infection. Due to antibiotic resistance and contamination of antibiotics in the milk of diseased animals; alternative therapeutic agents are required to cure mastitis. Lytic bacteriophages and their gene products can be potential therapeutic agents against bacteria as they are host specific and less harmful than antibiotics. In this study, Staphylococcus aureus were isolated from milk samples of the infected animals and identified biochemically. SA phage was isolated from sewage water showing lytic activity against Staphylococcus aureus isolates. The highest lytic activity of bacteriophages was observed at 37°C and pH 7, and the most suitable storage condition was at 4°C. SA phage efficiently reduced bacterial growth in the bacterial reduction assay. The characterization and bacterial growth reduction activity of the bacteriophages against Staphylococcus aureus signifies their underlying potential of phage therapy against mastitis.

  20. Staphylococcus aureus en quemaduras: estudio de incidencia, tendencia y pronóstico

    National Research Council Canada - National Science Library

    A. García-Urquijo; J.A. Rodríguez-Rodríguez; R. Rodríguez-Pérez; Lorenzo-Manzanas; G. Hernández-González

    2015-01-01

    ... Milián Castro" de Santa Clara, en Villa Clara, Cuba, con el objetivo de caracterizar el comportamiento del aislamiento de Staphylococcus aureus en heridas por quemaduras de pacientes ingresados. Se realizó...

  1. Tolerance of Salmonella Enteritidis and Staphylococcus aureus to surface cleaning and household bleach

    NARCIS (Netherlands)

    Kusumaningrum, H.D.; Paltinaite, R.; Koomen, A.J.; Hazeleger, W.C.; Rombouts, F.M.; Beumer, R.R.

    2003-01-01

    Effective cleaning and sanitizing of food preparation sites is important because pathogens are readily spread to food contact surfaces after preparation of contaminated raw products. Tolerance of Salmonella Enteritidis and Staphylococcus aureus to surface cleaning by wiping with regular, microfiber,

  2. The nosocomial transmission rate of animal-associated ST398 meticillin-resistant Staphylococcus aureus

    NARCIS (Netherlands)

    Bootsma, M.C.J.|info:eu-repo/dai/nl/304830305; Wassenberg, M.W.M.; Trapman, J.P.; Bonten, M.J.M.

    2010-01-01

    The global epidemiology of meticillin-resistant Staphylococcus aureus (MRSA) is characterized by different clonal lineages with different epidemiological behaviour. There are pandemic hospital clones (hospital-associated (HA-)MRSA), clones mainly causing community-acquired infections

  3. The nosocomial transmission rate of animal-associated ST398 meticillin-resistant Staphylococcus aureus

    NARCIS (Netherlands)

    Bootsma, M.C.J.; Wassenberg, M.W.M.; Trapman, J.P.; Bonten, M.J.M.

    2011-01-01

    The global epidemiology of meticillin-resistant Staphylococcus aureus (MRSA) is characterized by different clonal lineages with different epidemiological behaviour. There are pandemic hospital clones (hospital-associated (HA-)MRSA), clones mainly causing community-acquired infections

  4. Local circulating clones of Staphylococcus aureus in Ecuador.

    Science.gov (United States)

    Zurita, Jeannete; Barba, Pedro; Ortega-Paredes, David; Mora, Marcelo; Rivadeneira, Sebastián

    The spread of pandemic Staphylococcus aureus clones, mainly methicillin-resistant S. aureus (MRSA), must be kept under surveillance to assemble an accurate, local epidemiological analysis. In Ecuador, the prevalence of the USA300 Latin American variant clone (USA300-LV) is well known; however, there is little information about other circulating clones. The aim of this work was to identify the sequence types (ST) using a Multiple-Locus Variable number tandem repeat Analysis 14-locus genotyping approach. We analyzed 132 S. aureus strains that were recovered from 2005 to 2013 and isolated in several clinical settings in Quito, Ecuador. MRSA isolates composed 46.97% (62/132) of the study population. Within MRSA, 37 isolates were related to the USA300-LV clone (ST8-MRSA-IV, Panton-Valentine Leukocidin [PVL] +) and 10 were related to the Brazilian clone (ST239-MRSA-III, PVL-). Additionally, two isolates (ST5-MRSA-II, PVL-) were related to the New York/Japan clone. One isolate was related to the Pediatric clone (ST5-MRSA-IV, PVL-), one isolate (ST45-MRSA-II, PVL-) was related to the USA600 clone, and one (ST22-MRSA-IV, PVL-) was related to the epidemic UK-EMRSA-15 clone. Moreover, the most prevalent MSSA sequence types were ST8 (11 isolates), ST45 (8 isolates), ST30 (8 isolates), ST5 (7 isolates) and ST22 (6 isolates). Additionally, we found one isolate that was related to the livestock associated S. aureus clone ST398. We conclude that in addition to the high prevalence of clone LV-ST8-MRSA-IV, other epidemic clones are circulating in Quito, such as the Brazilian, Pediatric and New York/Japan clones. The USA600 and UK-EMRSA-15 clones, which were not previously described in Ecuador, were also found. Moreover, we found evidence of the presence of the livestock associated clone ST398 in a hospital environment. Copyright © 2016 Sociedade Brasileira de Infectologia. Published by Elsevier Editora Ltda. All rights reserved.

  5. Alpha-Toxin Promotes Mucosal Biofilm Formation by Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Michele J Anderson

    2012-05-01

    Full Text Available Staphylococcus aureus causes numerous diseases in humans ranging from the mild skin infections to serious, life-threatening, superantigen-mediated Toxic Shock Syndrome (TSS. S. aureus may also be asymptomatically carried in the anterior nares, vagina or on the skin, which serve as reservoirs for infection. Pulsed-field gel electrophoresis clonal type USA200 is the most widely disseminated colonizer and a major cause of TSS. Our prior studies indicated that α-toxin was a major epithelial proinflammatory exotoxin produced by TSS S. aureus USA200 isolates. It also facilitated the penetration of TSS Toxin-1 (TSST-1 across vaginal mucosa. However, the majority of menstrual TSS isolates produce low α-toxin due to a nonsense point mutation at codon 113, designated hly, suggesting mucosal adaptation. The aim of this study was to characterize the differences between TSS USA200 strains [high (hla+ and low (hly+ α-toxin producers] in their abilities to infect and disrupt vaginal mucosal tissue. A mucosal model was developed using ex vivo porcine vaginal mucosa, LIVE/DEAD® staining and confocal microscropy to characterize biofilm formation and tissue viability of TSS USA 200 isolates CDC587 and MN8, which contain the α-toxin pseudogene (hly, MNPE (hla+ and MNPE isogenic hla knockout (hlaKO. All TSS strains grew to similar bacterial densities (1-5 x 108 CFU on the mucosa and were proinflammatory over 3 days. However, MNPE formed biofilms with significant reductions in the mucosal viability whereas neither CDC587, MN8 (hly+, or MNPE hlaKO, formed biofilms and were less cytotoxic. The addition of exogenous, purified α-toxin to MNPE hlaKO restored the biofilm phenotype. Our studies suggest α-toxin affects S. aureus phenotypic growth on vaginal mucosa, by promoting tissue disruption and biofilm formation; and α–toxin mutants (hly are not benign colonizers, but rather form a different type of infection, which we have termed high density pathogenic

  6. Development of the immune response in pneumonia due to Staphylococcus aureus (part 2

    Directory of Open Access Journals (Sweden)

    A.E. Abaturov

    2017-04-01

    Full Text Available The article analyzes the role of pattern-recognition receptors involved in recognition of pathogen-associated molecular patterns of Staphylococcus aureus. There are shown the basic operation of macrophage and monocyte NLRP3, NLRC5, NLRP7, AIM2 inflammasomes that form the active forms of pro-inflammatory cytokines IL-1-beta and IL-18 du-ring the development of pneumonia caused by Staphylococcus aureus.

  7. Development of the immune response in pneumonia induced by Staphylococcus aureus (part 3

    Directory of Open Access Journals (Sweden)

    A.E. Abaturov

    2017-05-01

    Full Text Available The article analyzes the key role of pro-inflammatory and anti-inflammatory cytokines in the development of immune response in pneumonia caused by Staphylococcus aureus based on the literature data. Genes associated with a predisposition to staphylococcal infection and/or determining its course are considered. Signal pathways inducing the production of interferons I, II and III type participating in elimination of Staphylococcus aureus are described.

  8. BIOAKTIFITAS MINYAK ATSIRI SEREH Cymbopogon citratus DC. TERHADAP PERTUMBUHAN BAKTERI Escherichia coli DAN Staphylococcus aureus

    OpenAIRE

    Rahman, Hasriani

    2013-01-01

    Penelitian ini mengenai bioaktifitas minyak atsiri sereh Cymbopogon citratus DC. terhadap pertumbuhan bakteri Escherichia coli dan Staphylococcus aureus. Penelitian ini bertujuan untuk mengetahui bioaktifitas dan sifat antibakteri minyak atsiri sereh Cymbopogon citratus DC. terhadap pertumbuhan bakteri Escherichia coli dan Staphylococcus aureus. Pengujian daya hambat dilakukan dengan metode difusi agar menggunakan 5 variasi konsentrasi 100%, 50%, 25%, 12,5% dan 6,25% b/v pada media MHA (Mull...

  9. Polymerase chain reaction assay for detection of Staphylococcus aureus in buffalo milk

    OpenAIRE

    Jain, V.K.; Kumar, S.; Sharma, A.; N. Sindhu

    2010-01-01

    In India, Haryana has the world’s best dairy type buffalo, the Murrah capable of milk yields as high as 35 kg a day. Clinical and Sub clinical mastitis exerts a negative impact on milk quality, quantity and animal health and profits. In India, Staphylococci are the main causative agents responsible for mastitis of economic importance. Therefore, a suitable and specific test is required for the rapid diagnosis of Staphylococcus aureus. For definitive diagnosis of Staphylococcus aureus in...

  10. The Patterns Of Selected Antibiotics Sensitivity And Resistance To Staphylococcus Aureus Isolates

    Directory of Open Access Journals (Sweden)

    Stanslaus Kiilu Musyoki

    2015-08-01

    Full Text Available Complications of Staphylococcus aureus infection have greatly increased in recent past because of the many invasive procedures increased cases of immunocompromised individuals and the uprising trends in increased antimicrobial resistance of S. aureus strains. Despite of these available information and by contrast with developed countries S. aureus associated disease are ranked low on the public-health agenda in Kenya and other developing countries. Therefore there is due reason to undertake an investigation and report the trends and patterns in a thorough manner majorly and especially regarding the antimicrobial resistance. The aim of this study was thus to determine the levels of drug resistance of Staphylococcus aureus to various classes of antibiotics. This data is of significance in improving baseline data on antibiotic resistance of S. aureus isolated from human clinical specimens for the prudent use of antibiotics and the coming up with policies on control programs. All culture isolates were confirmed as Staphylococcus aureus genus by various tests That is gram staining catalase and oxidase. Catalase positive gram positive and oxidase negative isolates were defined as Staphylococcus. Further analyses by mannitol salt agar fermentation of the isolates and positive coagulase tests indicated Staphylococcus aureus. The area of clearance of sensitivity and tolerance was measured in millimeters and categorized as sensitive resistant or intermediate. The present study reported that S. aureus was most sensitive to Azithromycin whereby 46 61 samples were sensitive. Penicillin on the hand was least sensitive showing 29 level of sensitivity. Methicillin Gentamicin had more than 50 level of sensitivity That is 41 55 and 40 53 respectively. Other antibiotic drugs including ampicillin augmentin and tetracycline demonstrated less than 50 sensitivity That is 29 39 32 43 and 33 44 respectively. Drug resistance for S. aureus was therefore reported to be

  11. Global spread of vancomycin-resistant Enterococcus faecium from distinct nosocomial genetic complex

    National Research Council Canada - National Science Library

    Willems, Rob J L; Top, Janetta; van Santen, Marga; Robinson, D Ashley; Coque, Teresa M; Baquero, Fernando; Grundmann, Hajo; Bonten, Marc J M

    2005-01-01

    ...) has crossed genus boundaries to methicillin-resistant Staphylococcus aureus. Spread of VRE, therefore, represents an immediate threat for patient care and creates a reservoir of mobile resistance genes for other, more virulent pathogens...

  12. UJI KEBERADAAN Staphylococcus aureus PADA SOSIS TRADISIONAL (URUTAN YANG BEREDAR DI PASAR TRADISIONAL DI DENPASAR, BALI

    Directory of Open Access Journals (Sweden)

    Ni Putu Niti Rahayu

    2014-07-01

    Full Text Available The aim of this study is to determine the total amount of Staphylococcus aureus in atraditional sausage (urutan sold in Denpasar traditional market in Bali. Sausage samples aretaken from four areas in Denpasar (North Denpasar, East Denpasar, West Denpasar, and SouthDenpasar. From each area, three traditional markets are selected and from each market 2merchants are chosen. The calculation of the number of Staphylococcus aureus is done byplatting method and by pour plate method. The results show that the highest number ofStaphylococcus aureus belongs to the North Denpasar region in the mount of 241,067 CFU/gwhile the lowest belongs to the region of West Denpasar with 71,233 CFU/g. These two resultsare significantly different with one another (P<0,05. The maximum limit of microbialcontamination in processed meats (sausages for Staphylococcus aureus based on IndonesianNational Standard (SNI is equal to 102 CFU / g. Based on the testing that has been done, allurutan contamination by the Staphylococcus aureus in Denpasar traditional market, hasexceeded the threshold amount of SNI.Keywords : Traditional Sausages (urutan, Staphylococcus aureus

  13. Vancomycin-Resistant Enterococci: Epidemiology, Infection Prevention, and Control.

    Science.gov (United States)

    Reyes, Katherine; Bardossy, Ana Cecilia; Zervos, Marcus

    2016-12-01

    Vancomycin-resistant enterococci (VRE) infections have acquired prominence as a leading cause of health care-associated infections. Understanding VRE epidemiology, transmission modes in health care settings, risk factors for colonization, and infection is essential to prevention and control of VRE infections. Infection control strategies are pivotal in management of VRE infections and should be based on patient characteristics, hospital needs, and available resources. Hand hygiene is basic to decrease acquisition of VRE. The effectiveness of surveillance and contact precautions is variable and controversial in endemic settings, but important during VRE outbreak investigations and control. Environmental cleaning, chlorhexidine bathing, and antimicrobial stewardship are vital in VRE prevention and control. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Analysis of epidemics of vancomycin-resistant Enterococci in Turkey

    Directory of Open Access Journals (Sweden)

    Suleyman Durmaz

    2015-02-01

    Full Text Available The first cases with vancomycin-resistant Enterococci (VRE isolation were reported in 1988 throughout the world, and in 1998 in Turkey. The number of the papers conducted on cases or epidemics in which VRE was isolated is in increase. In this study, it was aimed to evaluate some studies at this topic. In conclusion, it was observed that the VRE strains isolated in the same clinic within a short period had a high probability to be the same clone, that there was need for extra investigation for teicoplanin resistance in VRE strains in terms of vanB expression, that VRE colonisation was more common in patients with long term intensive care unit stay, and that eradication of VRE could be made with more strict precautions in comparison to other epidemic bacteria.

  15. Peppermint Oil Decreases the Production of Virulence-Associated Exoproteins by Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Xu-Ming Deng

    2011-02-01

    Full Text Available The present study aimed to evaluate the antimicrobial activity of peppermint oil against Staphylococcus aureus, and further investigate the influence of peppermint oil on S. aureus virulence-related exoprotein production. The data show that peppermint oil, which contained high contents of menthone, isomenthone, neomenthol, menthol, and menthyl acetate, was active against S. aureus with minimal inhibitory concentrations (MICs ranging from 64-256 µg/mL, and the production of S. aureus exotoxins was decreased by subinhibitory concentrations of peppermint oil in a dose-dependent manner. The findings suggest that peppermint oil may potentially be used to aid in the treatment of S. aureus infections.

  16. Vancomycin-Resistance Enterococci Infections in the Department of the Defense: Annual Report 2014

    Science.gov (United States)

    2015-07-22

    resistant organism (MDRO), methicillin-resistant Staphylococcus aureus (MRSA), as well as the common use of prophylactic vancomycin for surgical and...17. Muto CA, et al. SHEA guideline for preventing nosocomial transmission of multidrug- resistant strains of Staphylococcus aureus and Enterococcus...VRE initially emerged in 1987 in Europe. Within a decade of identification , it spread and became a pathogen of concern in US hospitals

  17. STAPHYLOCOCCUS AUREUS AND STREPTOCOCCUS PNEUMONIAE PREVALENCE AMONG ELDERLY ADULTS IN JAKARTA, INDONESIA.

    Science.gov (United States)

    Safari, Dodi; Harimurti, Kuntjoro; Khoeri, Miftahuddin Majid; Waslia, Lia; Mudaliana, Siti; A'yun, Hanun Qurrota; Angeline, Regina; Subekti, Decy

    2015-05-01

    We studied Staphylococcus aureus and Streptococcus pneumoniae carriage among elderly adults in Jakarta, Indonesia. Nasopharyngeal swabs were collected from 149 adults aged 60-97 years. Both S. aureus and S. pneumoniae were identified by conventional and molecular methods. Methicillin-resistant Staphylococcus aureus (MSRA) was determined by PCR and antibiotic susceptibility using the disk diffusion method. Pneumococcal serotyping was performed with sequential multiplex PCR. We found S. aureus and S. pneumoniae present in 42 and 4 elderly adults respectively, and MRSA prevalence of 6%. Serotypes 3, 6A/B, 15B/C and 35F were identified among the four pneumococcal isolates. The majority of S. aureus isolates were susceptible to chloramphenicol (93%) and sulfamethoxazole/trimethoprim (93%), followed by gentamicin (88%), erythromycin (83%), penicillin (79%) and tetracycline (74%). Thus S. aureus prevalence is higher than that of S. pneumoniae, and a high frequency of MRSA carried by elderly adults in Jakarta, Indonesia.

  18. Fresh garlic extract inhibits Staphylococcus aureus biofilm formation under chemopreventive and chemotherapeutic conditions

    Directory of Open Access Journals (Sweden)

    Panan Ratthawongjirakul

    2016-08-01

    Full Text Available Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA are the leading aetiological pathogens of nosocomial infections worldwide. These bacteria form biofilms on both biotic and abiotic surfaces causing biofilm-associated infections. Within the biofilm, these bacteria might develop persistent and antimicrobial resistant characteristics resulting in chronic infections and treatment failures. Garlic exhibits broad pharmaceutical properties and inhibitory activities against S. aureus. We investigated the effects of aqueous fresh garlic extract on biofilm formation in S. aureus ATCC25923 and MRSA strains under chemopreventive and chemotherapeutic conditions. The viable bacteria and biofilm levels were quantified through colony count and crystal violet staining, respectively. The use of fresh garlic extract under both conditions significantly inhibited biofilm formation in S. aureus strains ATCC25923 and MRSA. Garlic could be developed as either a prophylactic or therapeutic agent to manage S. aureus biofilm-associated infections.

  19. Comparative analysis of conjugative plasmids mediating gentamicin resistance in Staphylococcus aureus.

    OpenAIRE

    Goering, R V; Ruff, E A

    1983-01-01

    Five gentamicin-resistant clinical isolates of Staphylococcus aureus were found to contain self-transmissible plasmids of 32 to 37 megadaltons in size. Restriction endonuclease digests of the plasmids were markedly similar to those of reference plasmids of unrelated geographical origin, thus suggesting the significant contribution of common conjugal plasmids to the emergence of gentamicin resistance in S. aureus populations.

  20. Risk factors for Staphylococcus aureus nasal colonization in Danish middle-aged and elderly twins

    DEFF Research Database (Denmark)

    Andersen, P S; Larsen, Lisbeth Aagaard; Fowler, V G

    2013-01-01

    Staphylococcus aureus is a human commensal bacterium found in the nasal cavity and other body sites. Identifying risk factors for S. aureus nasal carriage is of interest, as nasal carriage is a risk factor for subsequent invasive infection. We recently investigated the influence of host genetics...

  1. Bovine Staphylococcus aureus secretes the leukocidin LukMF′ to kill migrating neutrophils through CCR1

    NARCIS (Netherlands)

    Vrieling, M.; Koymans, K.J.; Heesterbeek, D.A.C.; Aerts, P.C.; Rutten, V.P.M.G.|info:eu-repo/dai/nl/092848028; de Haas, C.J.C.; van Kessel, K.P.M.; Koets, A.P.|info:eu-repo/dai/nl/194306992; Nijland, R; van Strijp, J.A.G.

    2015-01-01

    Although Staphylococcus aureus is best known for infecting humans, bovine-specific strains are a major cause of mastitis in dairy cattle. The bicomponent leukocidin LukMF′, exclusively harbored by S. aureus of ruminant origin, is a virulence factor associated with bovine infections. In this study,

  2. Memory Th1 Cells Are Protective in Invasive Staphylococcus aureus Infection

    NARCIS (Netherlands)

    A.F. Brown (Aisling F.); A.G. Murphy (Alison G.); S.J. Lalor (Stephen J.); J.M. Leech (John M.); K.M. O’Keeffe (Kate M.); M. Mac Aogáin (Micheál); D.P. O’Halloran (Dara P.); K.A. Lacey (Keenan A.); M. Tavakol (Mehri); C.H. Hearnden (Claire H.); D. Fitzgerald-Hughes (Deirdre); H. Humphreys (Hilary); J.P. Fennell (Jérôme P.); W.J.B. van Wamel (Willem); T.J. Foster (Timothy J.); J.A. Geoghegan (Joan A.); E.C. Lavelle (Ed C.); T.R. Rogers (Thomas R.); R.M. McLoughlin (Rachel M.)

    2015-01-01

    textabstractMechanisms of protective immunity to Staphylococcus aureus infection in humans remain elusive. While the importance of cellular immunity has been shown in mice, T cell responses in humans have not been characterised. Using a murine model of recurrent S. aureus peritonitis, we

  3. Emergence and resurgence of meticillin-resistant Staphylococcus aureus as a public-health threat

    NARCIS (Netherlands)

    Grundmann, Hajo; Aires-de-Sousa, Marta; Boyce, John; Tiemersma, Edine

    2006-01-01

    Staphylococcus aureus is a gram-positive bacterium that colonises the skin and is present in the anterior nares in about 25-30% of healthy people.(1) Dependent on its intrinsic virulence or the ability of the host to contain its opportunistic behaviour, S aureus can cause a range of diseases in man.

  4. Neonatal colonization with Staphylococcus aureus is not associated with development of atopic dermatitis

    DEFF Research Database (Denmark)

    Skov, L; Halkjaer, L B; Agner, T

    2009-01-01

    BACKGROUND: Staphylococcus aureus in atopic skin has been associated with exacerbation of eczema. Objectives To investigate a possible association between neonatal colonization with S. aureus and the risk of atopic dermatitis (AD) during the first 3 years of life. MATERIALS AND METHODS: The study...

  5. Cross-Talk between Staphylococcus aureus and Other Staphylococcal Species via the agr Quorum Sensing System

    DEFF Research Database (Denmark)

    Canovas de la Nuez, Jaime; Baldry, Mara; Bojer, Martin S

    2016-01-01

    Staphylococci are associated with both humans and animals. While most are non-pathogenic colonizers, Staphylococcus aureus is an opportunistic pathogen capable of causing severe infections. S. aureus virulence is controlled by the agr quorum sensing system responding to secreted auto-inducing pep...

  6. Polymorphism, genetic exchange and intragenic recombination of the aureolysin gene among Staphylococcus aureus strains

    NARCIS (Netherlands)

    Sabat, Artur J.; Wladyka, Benedykt; Kosowska-Shick, Klaudia; Grundmann, Hajo; van Dijl, Jan Maarten; Kowal, Julia; Appelbaum, Peter C.; Dubin, Adam; Hryniewicz, Waleria

    2008-01-01

    Background: Staphylococcus aureus expresses several proteases, which are thought to contribute to the virulence of this bacterium. Here we focus on aureolysin, the major thermolysin-like metalloprotease. Despite the importance of aureolysin in the physiology and pathogenesis of S. aureus, relatively

  7. Heat-killed Staphylococcus aureus reduces atherosclerosis by inducing anti-inflammatory macrophages

    NARCIS (Netherlands)

    Frodermann, V.; van Duijn, J.; van Puijvelde, G. H. M.; van Santbrink, P. J.; Lagraauw, H. M.; de Vries, Margreet R; Quax, P. H. A.; Bot, I.; Foks, A. C.; de Jager, S. C. A.; Kuiper, J.

    Background Staphylococcus aureus cell wall components can induce IL-10 responses by immune cells, which may be atheroprotective. Therefore, in this study, we investigated whether heat-killed S. aureus (HK-SA) could inhibit the development of atherosclerosis. Methods Atherosclerosis-susceptible LDL

  8. Heterologously expressed Staphylococcus aureus fibronectin-binding proteins are sufficient for invasion of host cells

    NARCIS (Netherlands)

    Sinha, B; Francois, P; Que, Y A; Hussain, M; Heilmann, C; Moreillon, P; Lew, D; Krause, K H; Peters, Georg; Herrmann, M

    2000-01-01

    Staphylococcus aureus invasion of mammalian cells, including epithelial, endothelial, and fibroblastic cells, critically depends on fibronectin bridging between S. aureus fibronectin-binding proteins (FnBPs) and the host fibronectin receptor integrin alpha(5)beta(1) (B. Sinha et al., Cell.

  9. Influence of antibiotic pressure on bacterial bioluminescence, with emphasis on Staphylococcus aureus

    NARCIS (Netherlands)

    Daghighi, Seyedmojtaba; Sjollema, Jelmer; Harapanahalli, Akshay; Dijkstra, Rene J. B.; van der Mei, Henny C.; Busscher, Henk J.

    2015-01-01

    Bioluminescence imaging is used for longitudinal evaluation of bacteria in live animals. Clear relations exist between bacterial numbers and their bioluminescence. However, bioluminescence images of Staphylococcus aureus Xen29, S. aureus Xen36 and Escherichia coli Xen14 grown on tryptone soy agar in

  10. Carriage of Staphylococcus aureus in Thika Level 5 Hospital, Kenya : a cross-sectional study

    NARCIS (Netherlands)

    Aiken, Alexander M; Mutuku, Irene M; Sabat, Artur J; Akkerboom, Viktoria; Mwangi, Jonah; Scott, J Anthony G; Morpeth, Susan C; Friedrich, Alexander W; Grundmann, Hajo

    2014-01-01

    BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) is an important nosocomial pathogen but little is known about its circulation in hospitals in developing countries. We aimed to describe carriage of S.aureus amongst inpatients in a mid-sized Kenyan government hospital. METHODS: We

  11. Accelerated procedure for the enumeration and identification of food-borne Staphylococcus aureus.

    OpenAIRE

    Lachica, R V

    1980-01-01

    A procedure was developed for accelerating to 29 h the enumeration and identification of both healthy and stressed cells of Staphylococcus aureus in foods. Baird-Parker agar medium was incubated for 24 h; S. aureus was identified within 5 additional h by using a simplified thermonuclease test.

  12. Community-associated methicillin-resistant Staphylococcus aureus causing orbital cellulitis in Australian children.

    Science.gov (United States)

    Vaska, Vikram L; Grimwood, Keith; Gole, Glen A; Nimmo, Graeme R; Paterson, David L; Nissen, Michael D

    2011-11-01

    Community-associated methicillin-resistant Staphylococcus aureus has only emerged recently as a cause of serious ocular infections in several different countries. At a tertiary pediatric hospital in Brisbane, Australia, community-associated methicillin-resistant S. aureus orbital cellulitis was first noted in 2009. Since then, it has caused 4 of 9 such infections.

  13. Host adaptation of bovine Staphylococcus aureus seems associated with bacteriological cure after lactational antimicrobial treatment

    NARCIS (Netherlands)

    Borne, van den B.H.P.; Nielen, M.; Schaik, van G.; Melchior, M.B.; Lam, T.J.G.M.; Zadoks, R.N.

    2010-01-01

    Staphylococcus aureus causes a wide range of diseases in multiple species. Some sequence types (ST) are observed in a variety of hosts, whereas other strains are mainly associated with bovine mastitis, suggesting host adaptation. We propose that host adaptation of Staph. aureus may influence

  14. Complete genome sequences of two Staphylococcus aureus ST5 isolates from California, USA

    Science.gov (United States)

    Staphylococcus aureus is a bacteria that can cause disease in humans and animals. S. aureus bacteria can transfer or exchange segments of genetic material with other bacteria. These segments are known as mobile genetic elements and in some instances they can encode for factors that increase the abil...

  15. Draft genome sequences of 14 Staphylococcus aureus ST5 isolates from California, USA

    Science.gov (United States)

    Staphylococcus aureus is a bacteria that can cause disease in humans and animals. S. aureus bacteria can transfer or exchange segments of genetic material with other bacteria. These segments are known as mobile genetic elements and in some instances they can encode for factors that increase the abil...

  16. Lipoteichoic acid and peptidoglycan from Staphylococcus aureus synergistically induce neutrophil influx into the lungs of mice

    NARCIS (Netherlands)

    Leemans, Jaklien C.; Heikens, Mirjam; van Kessel, Kok P. M.; Florquin, Sandrine; van der Poll, Tom

    2003-01-01

    Staphylococcus aureus is an important pathogen in nosocomial pneumonia. Lipoteichoic acid (LTA) and peptidoglycan (PepG) are part of the staphylococcal cell wall. Here we show that LTA and PepG act in synergy to cause polymorphonuclear cell recruitment in the pulmonary compartment during S. aureus

  17. Virulence and antimicrobial resistance of Staphylococcus aureus isolated from bloodstream infections and pneumonia in Southern Poland

    NARCIS (Netherlands)

    Pomorska-Wesolowska, Monika; Chmielarczyk, Agnieszka; Chlebowicz, Monika; Ziolkowski, Grzegorz; Szczypta, Anna; Natkaniec, Joanna; Romaniszyn, Dorota; Pobiega, Monika; Dzikowska, Miroslawa; Krawczyk, Lech; Koziol, Joanna; Wojkowska-Mach, Jadwiga

    2017-01-01

    Objectives: Staphylococcus aureus remains the most important cause of infections in hospitals and long-term care facilities. The aim of this study was to analyse the resistance, virulence, and epidemiological and genetic relationships of S. aureus from bloodstream infections (BSIs) and pneumonia

  18. Development of a Standard Test to Assess the Resistance of Staphylococcus aureus Biofilm Cells to Disinfectants

    NARCIS (Netherlands)

    Luppens, S.B.I.; Reij, M.W.; Heijden, van der R.W.; Rombouts, F.M.; Abee, T.

    2002-01-01

    A standardized disinfectant test for Staphylococcus aureus cells in biofilms was developed. Two disinfectants, the membrane-active compound benzalkonium chloride (BAC) and the oxidizing agent sodium hypochlorite, were used to evaluate the biofilm test. S. aureus formed biofilms on glass, stainless

  19. Physicochemical characterization of Staphylococcus aureus-lysing LysK enzyme in complexes with polycationic

    Science.gov (United States)

    Staphylococcus aureus causes many serious visceral, skin, and respiratory diseases. About 90% of clinical strains are multi-drug resistant, but the use of bacteriophage lytic enzymes offers a viable alternative to antibiotic therapy. LysK, the phage K endolysin can lyse S. aureus when purified and ...

  20. Nosocomial Staphylococcus Aureus Bacterimia among Nasal Carriers of Methicillin- Resistant and Methicillin-Susceptible Strains

    NARCIS (Netherlands)

    M. Pujol (Miquel); C. Pena; R. Pallares (Roman); J. Ariza (Javier); J. Ayats (Josefina); M.A. Dominguez; F. Gudiol (Francesc)

    1996-01-01

    textabstractObjectives To determine the relevance of nasal carriage of Staphylococcus aureus, either methicillin-sensitive (MSSA) or methicillinresistant (MRSA), as a risk factor for the development of nosocomial S aureus bacteremia during an MRSA outbreak. patients and methods: In this prospective