新生儿耐甲氧西林金黄色葡萄球菌多位点序列分型与耐药相关性分析

Multilocus sequence typing and resistance of methicillin-resistant staphylococcus aureus isolates in the newborn

目的研究新生儿科耐甲氧西林金黄色葡萄球菌(MRSA)的分子特性及耐药性情况,探讨二者之间的相关性。方法选择MRSA的7个管家基因作为目的基因,对2008年4月至2009年10月新乡医学院儿科分离的21株MRSA进行PCR扩增测序,应用多位点序列分型(MLST)技术对其分子特性和遗传特性进行分析,同时采用纸片扩散法检测其对13种抗生素的耐药情况。结果 21株MRSA可扩增得到24个等位基因,13个序列型,其中ST239序列型最多,占28.57%,其次为ST5序列型,占14.29%。药敏试验显示除了万古霉素和利福平外,对其他抗生素均耐药,耐药率为57%～100%。结论本地区新生儿科MRSA主要流行的克隆系为ST239和ST5,耐药性与序列型及序列克隆系相关性差。

Objective To study the antimicrobial resistant profiles and genotype of methicillin-resistant staphylococcusaureus isolates from the newborn, and discuss their relationship. Methods Seven pairs of S.aureus home-keeping gene were chosen as target gene, PCR was applied to amplify genotype of 21 samples from the newborn from Apr.2008 to Oct. 2009 in Department of Pediatrics, Xinxiang Medical College, and product sequence was analyzed by multilocus sequence typing（MLST）. Susceptibility for 13 antibiotics was detected by using slip diffuse method. Results MLST analysis of 120 isolates identified 24 alleles and 13 STs, in which the most prevalent genotype was ST239 （28.57%）, followed by ST5 （14.29%）. All isolates were resistant to other antibiotics except those that were susceptible to VAN and RIF, the resistant rate being 57% - 100%. Conclusion The most Prevalent genotype of MRSA is ST239 and ST5 in newborn department of our affiliated hospital. There is no obvious relationship between genotype and drug-resistance.