烧伤患者分离金黄色葡萄球菌耐药性与耐药基因研究

Investigation of drug resistance and antibiotic-resistant gene distribution of Staphylococcus aureus isolated from burn ward

目的了解烧伤病房患者分离金黄色葡萄球菌的耐药性及耐药基因分布,探讨烧伤患者易感染金黄色葡萄球菌的原因。方法收集2013年7-12月医院烧伤病房患者的金黄色葡萄球菌,菌种鉴定采用法国生物梅里埃公司VITEK-2Compact细菌鉴定仪,并进一步作spa基因PCR检测,药敏试验采用法国生物梅里埃公司VITEK-2Compact系统进行,通过PCR方法分析其耐药基因mecA、aac6′/aph2″、aph3′-Ⅲ、ant4′、ermA、ermB、ermC、mphC、msrA、tetM、tetK、qacA、bsa的表达。结果共收集金黄色葡萄球菌20株,其中19株来源于创面、1株来源于留置导管;金黄色葡萄球菌对青霉素G的耐药率为100.0%,对万古霉素、替考拉宁、利福平等耐药率均为0;mecA和bsa基因检测阳性率均为55.0%,aac6′/aph2″、aph 3′-Ⅲ基因检测阳性率分别为50.0%和45.0%。结论烧伤患者分离的20株金黄色葡萄球菌中mecA及bsa基因检出率较高,是烧伤患者易于感染金黄色葡萄球菌的原因,耐药基因检测提示其对季胺类消毒剂消毒皮肤效果可能欠佳。

OBJECTIVE To investigate drug resistance and antibiotic-resistant gene distribution of Staphylococcus aureus isolated from burn ward so as to discuss the causes for the infections.METHODS S.aureus isolated from our unit from Jul.to Dec.2013 were collected,and vitek-2Compact bacteria analyzer was adopted to detect strains and further detect the expression of protein A（spa）,and the drug resistance was detected by vitek-2Compact system.PCR was used to analyze the expression of the drug-resistant gene mecA,aac6′/aph2″,aph3′-Ⅲ,ant4′,ermA,ermB,ermC,mphC,msrA,tetM,tetK,qacA,and bsa.RESULTS Totally 20 strains of S.aureus were collected,including 19 isolated from wounds and 1strain from central venous catheter;S.aureus were 100.0% resistant to pennicillin,but all sensitive vancomycin,teicoplanin and rifampicin.Both mecAand bsagens expression rates were 55.0%,and aac6′/aph2″,and aph 3′-Ⅲ got the gene testing positive rates of 50.0% and 45.0%.CONCLUSIONThe detection rates of mecAand bsaare relatively higher in the 20 strains of S.aureusisolated from the burn patients and they were the main causes for S.aureus infections.The test of drug-resistance gene indicated that skin microorganisms were not sensitive to quaternary ammonium disinfectant.