多中心耐利奈唑胺凝固酶阴性葡萄球菌耐药机制及同源性分析  

Resistance mechanism and homology analysis of linezolid-resistant coagulase-negative staphylococci in a multicenter study

作　　者：周万青[1] 宋熙晶 生媛[2] 姜飞 徐杰[5] 张之烽[1] 沈瀚[1] ZHOU Wanqing;SONG Xijing;SHENG Yuan;JIANG Fei;XU Jie;ZHANG Zhifeng;SHEN Han(Department of Laboratory Medicine,the Affiliated Hospital of Nanjing University Medical School,Nanjing 210008,Jiangsu;Department of Hospital Infection-Control,Nanjing Drum Tower Hospital,the Affiliated Hospital of Nanjing University Medical School,Nanjing 210008,Jiangsu;School of Medicine,Southeast University,Nanjing 210009,Jiangsu;Department of Laboratory Medicine,the Affiliated Hospital of Xuzhou Medical University,Xuzhou 221002,Jiangsu;Department of Laboratory Medicine,the First Affiliated Hospital of Soochow University,Suzhou 215006,Jiangsu,China)

机构地区：[1]南京大学医学院附属鼓楼医院检验科,南京210008 [2]南京大学医学院附属鼓楼医院医院感染管理科,南京210008 [3]东南大学医学院,南京210009 [4]徐州医科大学附属医院检验科,江苏徐州221002 [5]苏州大学附属第一医院临床检测中心,江苏苏州215006

出　　处：《临床检验杂志》2020年第1期29-33,共5页Chinese Journal of Clinical Laboratory Science

基　　金：南京市医学科技发展资金(QRX17143;YKK17056)

摘　　要：目的:了解江苏地区利奈唑胺耐药凝固酶阴性葡萄球菌耐药机制及菌株流行性。方法:收集2017—2018年江苏省3家三级医院临床和环境分离利奈唑胺耐药凝固酶阴性葡萄球菌共38株(头状葡萄球菌32株、人葡萄球菌4株、表皮葡萄球菌1株和缓慢葡萄球菌1株),采用微量肉汤稀释法检测常规药物的敏感性,并采用E-test试验检测菌株对利奈唑胺的最低抑菌浓度(MIC);采用PCR扩增和测序技术检测cfr、optrA、23S rRNA第V功能区基因;采用脉冲场凝胶电泳(PFGE)对分离菌株进行同源性分析。结果:38株凝固酶阴性葡萄球菌对利奈唑胺、青霉素和苯唑西林均耐药,对万古霉素均敏感;对克林霉素、左氧氟沙星和环丙沙星的耐药率大于95%;38株菌株中检出cfr基因31株;23S rRNAⅤ功能区检出G2576T突变35株,其中2株人葡萄球菌同时检出C2319T突变,另检出C2319T突变人葡萄球菌和表皮葡萄球菌各1株;所有菌株均未检出optrA基因;32株头状葡萄球菌PFGE具有高度的相似性,均为同一个克隆株;4株人葡萄球菌为同一克隆株。结论:江苏地区流行的耐利奈唑胺凝固酶阴性葡萄球菌主要是由cfr基因和23S rRNAⅤ功能区基因突变造成,并存在头状葡萄球菌和人葡萄球菌的克隆播散。Objective:To investigate the resistance mechanism and prevalence of linezolid-resistant coagulase-negative staphylococci in Jiangsu Province.Methods:A total of 38 strains of linazolid-resistant coagulase-negative staphylococci,including 32 strains of Staphylococcus capitis,4 strains of Staphylococcus hominis,1 strain of Staphylococcus epidermidis and 1 strain of Staphylococcus lentus,were collected from the clinical and environmental samples of three tertiary hospitals in Jiangsu Province during 2017 and 2018.The drug sensitivity of these strains were detected by the broth dilution method,and the minimal inhibitory concentration(MIC)of linezolid was detected by E-test.The genes in domain V of 23S rRNA,cfr and optrA genes were detected by PCR and sequencing technology.The homology analysis of these strains was performed with the pulsed field gel electrophoresis(PFGE).Results:All of 38 strains of coagulase-negative staphylococci were resistant to linezolid,penicillin and oxacillin,and were sensitive to vancomycin.The drug resistance rates to clindamycin,levofloxacin and ciprofloxacin were above 95%.Cfr gene was detected in 31 out of 38 strains.The G2576T mutation in domain V of 23S rRNA was detected in 35 strains,in which C2319T mutation was also detected in 2 strains of Staphylococcus hominis.In addition,C2319T mutation was also found in 1 strain of Staphylococcus hominis and 1 strain of Staphylococcus epidermidis.All strains were negative for optrA gene.PFGE showed that 32 strains of Staphylococcus capitis were highly similar and from the same clone,and that 4 strains of Staphylococcus hominis were also from the same clone.Conclusion:The prevalent linezolid-resistant coagulase-negative staphylococci in Jiangsu Province are mainly caused by cfr gene and gene mutations in domain V of 23S rRNA,and there are clonal spread of Staphylococcus capitis and Staphylococcus hominis.

关 键 词：凝固酶阴性葡萄球菌 利奈唑胺 耐药基因 克隆播散 

分 类 号：R446.5[医药卫生—诊断学]