粪肠球菌分子分型特点及其与泰利霉素敏感性的关系

目的 了解临床分离的粪肠球菌分子分型特征及其与泰利霉素药物敏感性之间的关系。方法 收集深圳市南山医院2010-2016年不同临床标本分离的粪肠球菌320株，采用多位点序列分型技术进行分型，用微量肉汤稀释法测定菌株对泰利霉素的最低抑菌浓度，采用PCR检测耐药基因ermB的分布。结果 320株粪肠球菌分为48个ST型和56株新的ST分型，以ST16、ST179型为主。ST16型85株（26.6%），其中72株（84.7%）ermB阳性，29株（34.1%）对泰利霉素敏感，10株（11.8%）中介，46株（54.1%）耐药；ST179型80株（25.0%），其中71株（88.8%）ermB阳性，15株（18.8%）对泰利霉素敏感，4株（5.0%）中介，61株（76.3%）耐药。结论 该院粪肠球菌以ST16、ST179为优势菌株，该两型菌群高比例携带ermB基因，对泰利霉素耐药率较高。

Characteristics of molecular typing of Enterococcus faecalis and its relationship with susceptibility to telithromycin

Objective To reveal characteristics of molecular typing of clinically isolated Enterococcus faecalis (E. faecalis) and its relationship with susceptibility to telithromycin. Methods 320 strains of E. faecalis isolated from different clinical specimens in Nanshan Hospital of Shenzhen City from 2010 to 2016 were collected, genotyping of E. faecalis was performed by multilocus sequence typing (MLST), minimum inhibitory concentration of telithromycin to strains was determined by broth microdilution method, and distribution of drug-resistant gene ermB was detected by polymerase chain reaction (PCR). Results 320 strains of E. faecalis were divided into 48 ST types and 56 new ST types, mainly ST16 and ST179. 85 strains (26.6%) were ST16, 72 (84.7%) of which were positive for ermB, 29 (34.1%) were susceptible to telithromycin, 10 (11.8%) were intermediate, 46(54.1%) were resistant to telithromycin; 80 strains (25.0%) were ST179, 71(88.8%) of which were positive for ermB, 15(18.8%) were susceptible to telithromycin, 4 (5.0%) were intermediate, and 61 (76.3%) were resistant to telithromycin. Conclusion ST16 and ST179 are dominant strains of E. faecalis in this hospital, they carry ermB gene in a high proportion and have high resistance rate to telithromycin.