56株B族链球菌血清型耐药性及多位点序列分型研究  

The serotypes,antibiotic susceptibility and MLST of 56 strains of Group B streptococcus

作　　者：仝净净 王萍[1] 史伟[1] 姚开虎[1] 俞桑洁[1] 杨永弘[1] 

机构地区：[1]首都医科大学附属北京儿童医院北京市儿科研究所儿科学国家重点学科教育部儿科重大疾病研究重点实验室,北京100045

出　　处：《中国实用儿科杂志》2015年第3期194-198,共5页Chinese Journal of Practical Pediatrics

基　　金：北京市科委行业定额经费自主项目(2014-bjsekyjs-3);北京市留学人员科技活动项目择优资助经费

摘　　要：目的研究B族链球菌（GBS）的血清型、耐药性和多位点序列分型,供防治GBS感染参考。方法 2012—2013年间共收集到56株GBS菌株,自就诊于北京市妇产医院和北京大兴医院的妊娠35-37周孕妇的阴道和直肠拭子的分离培养。采用乳胶凝集试验检测菌株的血清型,E-test法和纸片扩散法检测细菌对9种抗生素的敏感性,PCR方法检测红霉素耐药基因ermB和mefA,管家基因测序确定菌株的序列型（ST）,eBURST软件分析菌株间亲缘性关系。结果 56株菌共鉴定出5种血清型,常见型为Ⅲ型（32.1%）、Ⅰa型（17.9%）、Ⅰb型（16.1%）和Ⅴ型（14.3%）。分离株对青霉素和头孢曲松均敏感,对左氧氟沙星、红霉素、克拉霉素、阿奇霉素、泰利霉素、克林霉素和四环素的不敏感率依次为39.3%、85.7%、92.9%、98.2%、30.4%、73.2%和91.0%。56株菌株共检测出14种STs,ST19（30.4%）最为常见。Ⅲ型菌株主要属于ST19（14/18）,92.9%的Ⅲ/ST19型菌株对左氧氟沙星耐药,75%的左氧氟耐药菌株属于CC19。44株红霉素耐药菌株中,32株（72.7%）erm B阳性。结论北京GBS菌株以Ⅲ、Ⅰa、Ⅰb、Ⅴ型常见;GBS菌株对青霉素和头孢曲松敏感,对红霉素和克林霉素等耐药率高,超过90%的Ⅲ/ST19型菌株耐左氧氟沙星;红霉素耐药菌株多携带ermB。Objective To investigate serotype,antibiotic susceptibility and multilocus sequence type（MLST）profiles of GBS in order to provide references for prevention and treatment of GBS infections.Methods We collected 56 strains isolated from vaginal and rectal swabs collected from pregnant women of 35-37 weeks in two hospitals of Beijing. All isolates were identified with CAMP test and Latex agglutination assay and serotyped with Strep-B-Latex kit. Then they were detected on antibiotic susceptibilities,macrolide resistance genes and multilocus sequence type（MLST）.Results Serotype Ⅰa,Ⅰb,Ⅲ and Ⅴ were determined in our study. Serotype Ⅲ（32.1%）,Ⅰa（17.9%）,Ⅰb（16.1%）and Ⅴ（14.3%）were dominant. Penicillin and Ceftriaxone remained efficacious in all cases,whereas the rate for macrolide-resistance and Clindamycin-resistance were strikingly high. Non-susceptible rates of levofloxacin,erythromycin,clarithromycin,azithromycin,telithromycin,clindamycin and tetracycline were 39.3%,85.7%,92.9%,98.2%,30.4%,73.2% and 91%. A total of 14 STs were identified in all isolates,and ST19（30.4%）was the most predominant. The rate of fluoroquinolone-resistant among serotype Ⅲ was higher than other serotypes. Among 44 isolates of erythromycin-resistant,32（72.7.0%）carried the ermB gene.Conclusion Serotype Ⅰa,Ⅰb,Ⅲ and Ⅴ are determined in GBS strains from Beijng. Penicillin and ceftriaxone remained efficacious in all cases,whereas the rate for macrolide-resistance and clindamycin-resistance was strikingly high. More than90% of Ⅲ/ST19 isolates were resistant to levofloxacin and most of erythromycin-resistant isolates carry the ermB gene.

关 键 词：B族链球菌 血清型 耐药性 多位点序列分型 

分 类 号：R72[医药卫生—儿科]