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

摘要:

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WalkWAY96PLUS 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：ST 88、ST 121、ST 221、ST 82、ST 239 及ST 399， 其中以ST 239（61/67，91.04%）为主，耐药性分析显示SCCmec Ⅲ型MRSA 菌株表现为多重耐药。结论 ST239-MRSA-SCCmec Ⅲ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。

Abstract:

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.