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@#Introduction: Coagulase-negative staphylococci (CoNS) is often considered as a culture contaminants but it can potentially be pathogenic to patients with risk factors. A combination of species identification and clinical criteria has been suggested in determining true CoNS bacteraemia. Objectives: To identify the species distribution, antibiotic susceptibility patterns and clinical profiles of CoNS isolated from blood cultures among paediatric patients in Hospital Kuala Lumpur (HKL). Methods: This study involved CoNS isolation from blood cultures of paediatric in-patients of the Paediatric Institute HKL. Isolates were identified to species level using Analytical Profile Index Staph identification strips and antimicrobial susceptibility pattern following Kirby-Bauer Disc Diffusion method. The clinical profiles of patients were obtained from their medical records. Results: Eleven CoNS species were identified from 148 isolates. Staphylococcus epidermidis was the most frequent species isolated (67.6%). The majority of the isolates showed resistance to penicillin (85.8%); while 70.3% were methicillin-resistant (MR) CoNS, which demonstrated a significant association with true infection (p=0.021). Predictors for significant CoNS infection included thrombocytopaenia, presence of predisposing factors, nosocomial infection, blood collected from peripheral vein, and CoNS isolated from two consecutive blood cultures. The most common predisposing factors for the isolation of CoNS were the presence of peripheral (54.1%) and central venous catheters (35.1%). Conclusion: CoNS can cause significant bloodstream infections. The isolation of CoNS from blood cultures should be carefully interpreted by considering the predictive factors. Local data regarding predictive factors of patients with culture-positive CoNS, species distribution and antimicrobial susceptibility pattern are useful to determine the significance of blood culture results and care management of patients
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Objective We aimed to elucidate the prevalence and the antibiotic resistance spectrum of nasal coagulase-negative staphylococci (CoNS) colonization among HIV infectors in Guangzhou. Method After isolation and identification, all CoNS isolates were tested for the antibiotic susceptibility, and the antibiotic resistance genes. Result Among the 1 001 HIV infectors, the prevalence of CoNS and MRCoNS were 57.44% and 48.15%, respectively. The three predominant resistant antibiotics of MRCoNS isolates were penicillin, erythromycin and trimethoprim-sulfame thoxazole, while predominant detection rates of genes were Aac(6’)-aph(2’)、ermC and linA genes. The multidrug resistance rate of MRCoNS isolates were significantly higher than methicillin-susceptible coagulase-negative staphylococci (MSCoNS) isolates (80.69% versus 39.66%, P<0.001, OR=6.36). Conclusions The prevalence and multidrug resistant rates of nasal colonization CoNS and MRCoNS are high among HIV infectors in Guangzhou. MRCoNS isolates were 6.36 times more likely to be of multidrug resistance than MSCoNS isolates.
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Introduction: Coagulase Negative Staphylococci, the most commonly isolated pathogen are becoming emerging threats to the community as well as to the nosocomial environment. The present study underscores the distribution of Staphylococcal cassette chromosome mec (SCCmec) types among Methicillin resistant Coagulase Negative Staphylococci from the environmental origin. Methods and Materials: Environmental and food sample (n = 460) from different location of northeastern region of India were collected for a period of one year and were phenotypically and genotypically screened using cefoxitin disc and PCR techniques for mecA and mecC gene detection. All the MR-CoNS isolates possessing mecA gene were subjected to 16srDNA sequencing for species identification. SCCmec typing was determined by evaluating using primer sets from type I to type V. Antibiotic susceptibility testing was performed for all the isolates. Statistical analysis with chi-square test using SPSS-21 statistical software. Results: Methicillin resistance shown by one hundred forty three isolates were carried out for molecular analysis, among them 53.84% serves as mecA carrier. Distribution of Staphylococcus haemolyticus was more frequent and was found that SCCmec types II and V were predominant among the study isolates. Linezolid was the drug of choice for the CoNS isolates. Statistical analysis showed an insignificant result for the tested antibiotics and SCCmec types. Conclusion: This study therefore interprets the relative importance of SCCmec types among MR-CoNS isolates.
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Objective To learn about the antibiotic resistance status of methicillin resistant coagulase negative staphylococcus(MRCNS),and to investigate the distribution and resistant feature of different staphylococcal chromosomal cassette mec(SCCmec) genotypes of children in Anhui,so as to guide clinical medication.Methods Resistance phenotype screening was conducted in coagulase negative staphylococcus,which were isolated from clinical strains in children in Anhui from 2010 to 2014 each year in September.MecA gene was detected by using PCR method in order to collect MRCNS.Minimal inhibitory concentrations (MIC) of 16 antibiotics were determined by adopting agar dilution method.Vacomycin-resistant strains were identified with population analysis and the Brain Heart Infusion vancomycin screen agar dilution method recommended by Clinical and Laboratory Standards Institute in 2013.Van gene and SCCmec types were detected by using PCR method.Results A total of 148 MRCNS strains were detected through the resistance phenotype screening and the detection of mecA gene.There were methicillin resistant staphylococcus epidermidis,methicillin resistant staphylococcus haemolyticus,methicillin resistant staphylococcus hominis,and other kinds of MRCNS,and the proportions of them were 44.59％ (66/148 cases),25.68％ (38/148 cases),19.59％ (29/148 cases) and 10.14％ (15/148 cases),respectively.The analysis of antibiotic resistance showed the antimicrobial resistant rates of MRCNS to Penicillin,Cefoperazone,Cefotaxime,Ceftriaxone,lmipenem and Meropenem were all 100％,to Erythromycin and Azithromycin,Ciprofloxacin,Clindamycin,Gentamicin,Lewofloxacin,Rifampincin,Chloramphenicol,Teicoplanin and Vancomycin were 92.57％,97.98％,83.78％,79.05％,43.24％,35.81％,24.32％,8.78％,2.03％ and 0.68％,respectively.There was 1 heterogeneous Vancomycin-resistant strain,which was resistant to both Vancomycin and Teicoplanin (with MIC 32.00 mg/L and 64.00 mg/L).No vanA,vanB,vanC1 or vanC2/3 gene was detected from heterogeneous Vancomycin-resistant strain by PCR.Ⅰ to Ⅴ SCCmec genotypes were detected from 148 MRCNS strains,and the major SCCmec type was SCCmec type Ⅲ,which was followed by hybrid type.Three subtypes of SCCmec type Ⅳ were identified,including Ⅳa,Ⅳc and Ⅳd.There were 148 MRCNS strains that showed different resistant phenotypes to various antibiotics.Conclusions The MRCNS strains of children in Anhui province showed multiple resistance to antibiotics.It should be on alert when heterogeneous Vaneomycin-resistant strain appeared.There were several different SCCmec types among several kinds of MRCNS,and SCCmec Ⅲ genotype was the major epidemic isolate.There was no significant correlation between the different resistance rates of non-β-lactamase antibiotics and SCCmec genotypes in MRCNS.
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BACKGROUND: Doctors' white coats and neckties can become contaminated with potentially pathogenic bacteria and have a possibility of causing cross infections. Our objective was to determine the level of bacterial contamination and detect methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE) and Clostridium difficile present on the white coats and neckties of residents. METHODS: We sampled 28 long-sleeved white coats and 14 neckties worn by residents. The tested sites for white coats were the cuffs and lower front surfaces, and for neckties, the lower surfaces. Impressions of these sites were taken with the plates containing blood agar (BAP), mannitol salt agar supplemented with oxacillin (6microgram/mL), enterococcus screening agar supplemented with vancomycin (6microgram/mL) and phenyl ethanol agar. The colonies grown on each plate were Gram stained and identified by standard microbiological methods. RESULTS: Of the 28 white coats, 7 (25.0%) carried MRSA, and of the 14 neckties, 1 (7.1%) carried MRSA. The majority of white coats (96.4%) and all neckties (100.0%) carried methicillin-resistant coagulase negative staphylococci (MRCNS). None of the white coats and neckties carried VRE or C. difficile. CONCLUSION: Our results showed that white coats and neckties worn by residents were contaminated with MRSA and MRCNS. The preventive measures for clothing-borne cross contamination should be considered, especially when performing invasive procedures or having close contact with patients.