感染创面相关环境标本分离葡萄球菌的同源性分析

Homology analysis on Staphylococcus isolated from infectious woundrelated environmental specimens

摘要:

目的对某医疗机构葡萄球菌感染情况进行持续监测，对创面感染患者相关医源性环境检出的葡萄球菌进行分子溯源分析。方法采用实时荧光聚合酶链反应（PCR）和分类培养鉴定相结合的方法，对该医疗机构5例创面感染患者相关的医源性环境进行采样检测，并进行金黄色葡萄球菌多位点序列分析和MecA基因的分型分析。结果采集医源性环境标本71份,葡萄球菌阳性26份（36.62%），其中23份检出甲氧西林耐药（MecA+）株（88.46%，23/26）。金黄色葡萄球菌甲氧西林耐药株占77.78%（7/9），凝固酶阴性葡萄球菌甲氧西林耐药株占95.00%（19/20）。多位点序列分析结果显示，分离的金黄色葡萄球菌以ST239为主（6株）；SCCMec分析，金黄色葡萄球菌以Ⅲ型为主，凝固酶阴性葡萄球菌以Ⅲ、Ⅳ型较多。结论医源性感染中葡萄球菌污染较多，且多为耐药株，应加强对耐药性葡萄球菌的持续监测，关注其变异对医疗机构医院感染的风险。

Abstract:

ObjectiveTo monitor Staphylococcus infection in a hospital, and trace the source of  Staphylococcus isolated from infectious woundrelated hospital environment by molecular analysis. MethodsBy combination of fluorescence quantitative polymerase chain reaction (FQPCR) and culture method, environmental specimens related to 5 patients with wound infection were taken and performed multilocus sequence  and MecA gene typing analysis. ResultsA total of 71 environmental specimens were taken, Staphylococcus accounted for 36.62%（n=26），88.46% (23/26 ) of which were MecA+ methicillinresistant strains. 77.78% （7/9）of  Staphylococcus aureus (S. aureus) and 95.00%（19/20）of coagulase negative Staphylococcus (CNS) were  methicillinresistant strains. Multilocus sequence analysis revealed that ST239 (n=6) was the most common sequence type in S. aureus；Staphylococcal cassette chromosome mec (SCCmec)   analysis showed that the major type of S. aureus was type Ⅲ, and CNS were type Ⅲ and Ⅳ. ConclusionStaphylococcus is common in healthcareassociated infection, and most Staphylococcus are multidrugresistant, continuous monitor on drugresistant Staphylococcus is necessary, and risk of Staphylococcus variant to medical institutes need to be paid attention.