尿液分离万古霉素耐药屎肠球菌耐药机制及毒力基因分析  

Resistance mechanism and virulence genes of vancomycin resistant Enterococcus faecium isolated from urine

作　　者：高硕[1] 朱宏[1] 周辉[1] 周万青[1] 沈瀚[1] GAO Shuo;ZHU Hong;ZHOU Hui;ZHOU Wanqing;SHEN Han(Department of Laboratory Medicine, Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, Nanjing 210008, 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

出　　处：《临床检验杂志》2022年第2期101-104,共4页Chinese Journal of Clinical Laboratory Science

基　　金：南京市医学科技发展资金(QRX17143,YKK18091)。

摘　　要：目的探讨尿液分离万古霉素耐药屎肠球菌(VREfm)耐药机制及毒力基因携带情况。方法收集临床中段尿分离屎肠球菌共88株,其中万古霉素耐药和敏感菌株分别为37株和51株。采用Vitek 2 Compact及配套GP67卡进行常规药物敏感性检测;采用E-test法复核万古霉素、替考拉宁的药敏结果。采用PCR及Sanger测序法检测万古霉素耐药vanA、vanB、vanD及vanM基因;采用PCR法检测肠球菌6种毒力基因cylA、esp、asa1、hyl、gelE和agg携带情况;统计分析万古霉素耐药菌株与敏感菌株之间毒力基因携带差异。结果37株VREfm对万古霉素的最低抑菌浓度(MIC)≥256μg/mL,对替考拉宁耐药率为73.0%(27/37),其中有35株检出vanA基因,其余2株检出vanM基因,均未检出vanB、vanD基因。37株VREfm以esp基因检出率最高(89.2%,33/37),其次为hyl(8.1%,3/37),其中携带esp-hyl双基因2株,携带asa1-gelE双基因1株。51株敏感菌株中esp基因检出率最高(74.5%,38/51),其次为hyl基因(29.4%,15/51),未检出其余4种毒力基因。万古霉素耐药菌株中hyl基因检出率低于敏感菌株,差异有统计学意义(P<0.05)。esp基因携带率在万古霉素敏感和耐药株间差异无统计学意义(P>0.05)。结论尿液分离万古霉素耐药屎肠球菌主要由vanA介导耐药,主要携带的毒力基因为esp和hyl,hyl毒力基因携带率低于万古霉素敏感菌株。Objective To investigate the drug resistance mechanism and virulence gene of vancomycin-resistant Enterococcus faecium(VREfm)isolated from urine.Methods A total of 88 strains of Enterococcus faecium isolated from clinical urine samples were collected,including 37 vancomycin resistant and 51 vancomycin sensitive strains.Vitek 2 Compact and GP67 card were used for routine drug sensitivity detection.The drug resistances of vancomycin and teicoplanin were checked by E-test.vanA,vanB,vanD and vanM genes were detected by PCR combined with Sanger sequencing technique.Six virulence genes of Enterococci,including cylA,esp,asa1,hyl,gelE and agg,were detected by PCR.The difference of virulence genes between vancomycin resistant and sensitive strains was statistically analyzed.Results The minimum inhibition concentration(MIC)of vancomycin was≥256μg/mL in 37 VREfm strains,and the resistance rate to teicoplanin was 73.0%(27/37).vanA gene was detected in 35 strains,vanM gene was detected in the other 2 strains,and vanB and vanD genes were not detectable.Among the 37 VREfm strains,esp(89.2%,33/37)gene showed the highest detection rate,followed by hyl(8.1%,3/37),of which esp-hyl double gene were carried in 2 strains.asa1-gelE double gene was detectable in only 1 strain.Among the 51 sensitive strains,the detection rate of esp gene(74.5%,38/51)was the highest,followed by hyl gene(29.4%,15/51),and the other four virulence genes were not detectable.The detection rate of hyl gene in vancomycin resistant strains was lower than that in sensitive strains(P<0.05),while the difference of esp gene carrying rate between vancomycin-sensitive and resistant strains was not statistically significant(P>0.05).Conclusion The resistance of Enterococcus faecium isolated from clinical urine samples is mainly mediated by vanA.The main virulence genes carried were esp and hyl,and the carrying rate of hyl gene in vancomycin resistant strains was lower than that in sensitive strains.

关 键 词：屎肠球菌 万古霉素 耐药机制 毒力基因 

分 类 号：R446.5[医药卫生—诊断学]