Objective To study antimicrobial resistance and genotyping of methicillin-resistant Staphylococcus au-reus(MRSA). Methods A total of 967 no-repetitive strains of Staphylococcus aureus(S.aureus)isolated from a hospital between January 2014 and November 2015 were collected,antimicrobial susceptibility testing,mecA gene,and Panton-Valentine leukocidin gene(PVL gene)were detected;staphylococcal cassette chromosome mec(SCCmec)typing,multilocus sequence typing(MLST),S.aureus protein A(spa)gene typing,and S.aureus ac-cessory gene regulator(agr)typing were performed with multiplex polymerase chain reaction. Results Of 967 strains of S.aureus,210(21.72%)were MRSA;detection rate of MRSA from sputum specimen was higher than that of skin and soft tissue specimen(68.09% vs 1 1.83% ,P<0.05);vancomycin- and linezolid-resistant S.aureus strains were not found,susceptibility rates of MRSA to gentamicin,tetracycline,erythromycin,clindamycin,levo-floxacin,ciprofloxacin,moxifloxacin,nitrofurantoin,and rifampicin were all lower than those of methicillin-sensi-tive Staphylococcus aureus(MSSA),differences were all statistically significant(all P<0.05);antimicrobial sus-ceptibility rate of MRSA to compound sulfamethoxazole was higher than MSSA,difference was significant(P<0.05). Susceptibility rates of MRSA isolated from skin and soft tissue to gentamicin,levofloxacin,ciprofloxacin,moxifloxacin,and rifampicin were 86.90% -95.24%,while MRSA isolated from sputum were only 1.56% -15.63%.Of 967 strains of S.aureus,210 harbored mecA gene,10 harbored PVL gene,8(3.81%)of 210 MRSA strains weren't typed. The main types of MLST,SCCmec,spa,and agr were ST 239(n= 177 strains),type Ⅲ(n= 177 strains),t 030(n= 177 strains),and typeⅠ(n= 196 strains)respectively.Conclusion The main epidemic clone of MRSA strain in this hospital is ST239-MRSA-SCCmec III-t030,antimicrobial resistance is serious,monitoring on drug-resistant strains in hospital should be strengthened.%目的 研究耐甲氧西林金黄色葡萄球菌(MRSA)的耐药性及其基因分型.方法 收集某院2014年1月—2015年11月检出的非重复金黄色葡萄球菌967株,检测其药敏结果及m ecA抗性基因、杀白细胞素(PVL)基因;MRSA菌株经多重PCR进行葡萄球菌盒式染色体mec(SCC m ec)分型、多位点序列分型(MLST)、金黄色葡萄球菌蛋白A基因(spa)分型、金黄色葡萄球菌附属因子调节子(agr)分型.结果 967株金黄色葡萄球菌共检出210株 MRSA,MRSA检出率为21.72%;痰标本 MRSA 检出率高于皮肤软组织标本(68.09% vs 11.83%,P<0.05);金黄色葡萄球菌中未发现对万古霉素和利奈唑胺耐药菌株,MRSA对庆大霉素、四环素、红霉素、克林霉素、左氧氟沙星、环丙沙星、莫西沙星、呋喃妥因、利福平的敏感率均低于 MSSA,差异均有统计学意义(均P<0.05);MRSA对复方磺胺甲口恶唑的敏感率高于 MSSA,差异有统计学意义(P<0.05).皮肤软组织分离的 MRSA对庆大霉素、左氧氟沙星、环丙沙星、莫西沙星、利福平的敏感率为86.90% ~95.24%,而痰分离的 MRSA仅为1.56% ~15.63%.967 株金黄色葡萄球菌检测出210 株携带m ecA基因,10 株携带PVL基因,210 株MRSA 中有8 株未分型,占3.81%.MLST主要以ST 239(177株)为主;SCCmec分型主要以Ⅲ型(177株)为主;spa 分型主要以 t 030 (177株)为主;agr分型主要以Ⅰ型(196株)为主.结论 该院 MRSA 菌株主要流行克隆 ST239-MRSA-SCCmecⅢ-t030,耐药形势严峻,应加强医院内耐药菌株的监测.
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