粪肠球菌临床株对泰利唑胺体外抗菌活性的研究

目的 评价泰利唑胺体外抗粪肠球菌的活性，探讨泰利唑胺不敏感粪肠球菌的耐药机制及其多位点序列分型分布情况。方法 收集2011年1月1日—2016年6月30日深圳市南山区人民医院临床分离的粪肠球菌菌株，使用自动化仪器法及微量肉汤稀释法对分离菌株的耐药性进行检测。应用聚合酶链式反应（PCR）方法检测恶唑烷酮类抗生素耐药基因的携带情况，并采用多位点序列分型（MLST）对分离菌株进行分型。结果 共获得289株粪肠球菌，来源科室主要为外科（57.4%），标本来源主要为中段尿（126株，43.6%）。289株粪肠球菌对泰利唑胺敏感率为94.1%，对氨苄西林、呋喃西林和万古霉素有较高的敏感性（敏感率为97.9%~99.7%）。MLST结果显示，共分为47个ST型，优势ST分型为ST16和ST179，分别占29.1%（84株）和24.9%（72株），在泰利唑胺不敏感粪肠球菌中，ST16的比例高于ST179（P<0.05）。共检出泰利唑胺不敏感粪肠球菌17株，其携带optrA基因比例高于敏感株。结论 泰利唑胺对粪肠球菌的抗菌活性整体优于利奈唑胺，但对携带optrA基因的粪肠球菌则未显示出良好的抗菌活性。

In vitro antimicrobial activity of tedizolid against clinically isolated Enterococcus fecalis

Objective To evaluate in vitro antimicrobial activity of tedizolid(TZD) against Enterococcus faecalis(E. faecalis), and explore antimicrobial resistance mechanism and distribution of multilocus sequence typing (MLST) of tedizolid-non-susceptible E. faecalis. Methods E. faecalis isolates from Nanshan People's Hospital of Shenzhen City between January 1, 2011 and June 30, 2016 were collected, antimicrobial resistance of isolates was tested by automatic instrument method and micro-broth dilution method. Polymerase chain reaction (PCR) was used to detect the carrying status of oxazolidinone antibiotic resistance genes, isolated strains were typed by MLST. Results A total of 289 strains of E. faecalis were obtained, strains were mainly from department of surgery (57.4%) and main specimen source was midstream urine (126 strains, 43.6%). Susceptibility rate of 289 E. faecalis strains to TZD was 94.1%, susceptibility rates to ampicillin, furacillin and vancomycin were all high (97.9%-99.7%). MLST results showed that there were 47 ST types, the dominant ST were ST16 and ST179, accoun-ting for 29.1% (84 strains) and 24.9% (72 strains) respectively, among TZD-non-susceptible E. faecalis, the proportion of ST16 was higher than that of ST179 (P<0.05). A total of 17 strains of TZD-non-susceptible E. faecalis strains were isolated, the proportion of optrA gene carried by them was higher than that of susceptible strains. Conclusion TZD is superior to linezolid in antimicrobial activity against E. faecalis, but it has no good antimicrobial activity against E. faecalis carrying optrA gene.