耐甲氧西林金黄色葡萄球菌MLST联合SCCmec基因分型与耐药性分析

Drug resistance and MLST combined with SCCmec genotyping of Methicillin-resistant Staphylococcus aureus

目的了解滨州医学院附属医院MRSA菌株多位点序列分型(MLST)联合SCCmec基因型分布和各种基因型的耐药特征。方法采用聚合酶链反应(PCR)对MRSA菌株进行MLST联合SCCmec基因分型;采用Walk WAY96PLUS PC33药敏板检测MRSA抗菌药物敏感性。结果 SCCmec基因分型结果以Ⅲ型为主(63/67株,占94.03%),MLST分型共检测出6种基因型:ST88、ST121、ST221、ST82、ST239及ST399,其中以ST239(61/67,91.04%)为主,耐药性分析显示SCCmecⅢ型MRSA菌株表现为多重耐药。结论ST239-MRSA-SCCmecⅢ型菌株为鲁北地区MRSA主要流行菌株,该型菌株对多种抗生素呈多重耐药;MLST联合SCCmec基因分型方法是MRSA遗传背景研究简便快速的方法。

Objective To investigate the drug resistance and genetic background of Methicillin-resistant Staphylococcus aureus(MRSA).Methods Multilocus sequence typing(MLST)technique was introduced to identify sequence types(ST)of MRSA,SCCmec types were determined by multiplex PCR.MLST plus SCCmec typing of these strains were used for their genotyping at the same time.The susceptibility to antimicrobial agents was tested by micro-dilution method.Results Among the 67 isolates of MRSA,63(94.03%)isolates belonged to SCCmec type III;6 different genotypes were detected by MLST typing which included ST88,ST121,ST221,ST82,ST239 and ST399,and 61(91.04%)isolates belonged to ST239.Drug resistance analysis showed the MRSA strains of SCCmec type III were multi-resistant.Conclusions ST239-MRSA-SCCmec III genotype is the major epidemic strain in northern Shangdong Province,which has multiple resistance to antibiotics.MLST combined with SCCmec genotyping is a rapid and simple method of MRSA genotyping.