尿路感染大肠埃希菌ST131克隆株的分子生物学特征分析  

Molecular biological characterization of Escherichia coli sequence type 131 clone isolated from urinary tract infection

作　　者：卢燕芳[1] 李彬[2] 徐两蒲[1] 兰芳俊 吴志辉[1] 何清雯 LU Yanfang;LI Bin;XU Liangpu;LAN Fangjun;WU Zhihui;HE Qingwen(Department of Laboratory Medicine,Fujian Provincial Maternal and Child Hospital,Fuzhou 350001,China)

机构地区：[1]福建省妇幼保健院检验科,福州350001 [2]福建医科大学附属协和医院检验科 [3]宁波市妇女儿童医院检验科 [4]厦门市第二医院检验科

出　　处：《中国感染与化疗杂志》2019年第6期616-620,共5页Chinese Journal of Infection and Chemotherapy

基　　金：福建省科技创新联合资金项目（2017Y9049）;福建省卫计委中青年骨干人才培养项目（2015-ZQN-ZD-15）

摘　　要：目的了解福州某医院尿路感染大肠埃希菌ST131克隆株分子生物学特征。方法收集该院2014年8月-2015年8月尿培养临床分离大肠埃希菌357株,采用多重PCR对其进行系统发育分型,采用纸片扩散法进行药敏试验,通过PCR和多位点序列分型(MLST)对大肠埃希菌B2型菌株筛选出ST131型别,对其进行毒力基因和耐药基因检测。分析ST131和非ST131克隆株在毒力基因分布和耐药性的差异。结果 357株大肠埃希菌系统发育分型B2型162株,占45.4%。55株(34.0%)ST131克隆株均属于B2型,其分为两种血清型:O25b-ST131(36株,65.5%)和O16-ST131(19株,34.5%)。毒力基因iutA、kpsMT K5和traT在ST131克隆株的流行率显著高于B2型非ST131克隆株(P<0.05)。ST131克隆株对头孢唑林、头孢噻肟、头孢吡肟、甲氧苄啶-磺胺甲唑、环丙沙星和左氧氟沙星的耐药率显著高于非ST131克隆株(P<0.05)。结论该院尿路感染的大肠埃希菌中存在强毒力和多重耐药的大肠埃希菌ST131克隆株,须高度重视。提示O16-ST131亚克隆可能是大肠埃希菌ST131的重要类型,未来的研究不该忽视O16-ST131亚克隆群。Objective This study aimed to analyze the molecular biological characteristics of the Escherichia coli sequence type 131 clone isolated from urinary tract infection. Methods Three hundred and fifty seven E. coli strains were collected consecutively from urinary tract infection between August 2014 and August 2015 in Fujian Medical University Union Hospital. The isolates were assessed for phylogenetic groups by Multiplex polymerase chain reaction(PCR) and antimicrobial susceptibility by disk diffusion test. ST131 clone was identified by PCR and multilocus sequence typing(MLST), and characterized in terms of resistance genes and virulence factors. The distribution of virulence factors and antimicrobial resistance were compared between ST131 clone and non-ST131 clone. Results Phylogenetic analysis indicated that 162(45.4%) of the 357 isolates belonged to group B2, and 55 (34.0%) isolates of ST131 clone belonged to group B2. Two O types were identified in this study: O25 b(65.5%) and O16(34.5%). The prevalence of virulence genes iutA, kpsMT K5, and traT were significantly higher in ST131 clones than in nonST131 clones(P<0.05). Compared with ST131 clone, nonST131 clone showed lower resistance rate to ciprofloxacin, levofloxacin, cefazolin, cefepime, cefotaxime and trimethoprimsulfamethoxazole(P<0.05). Conclusions It is important to pay attention to the E. coli ST131 clone isolated from urinary tract infection, which is associated with higher virulence and antimicrobial resistance. The result implies that O16-ST131 subclone may be an important type of E. coli ST131 clone.

关 键 词：大肠埃希菌ST131克隆株 系统发育分型 毒力 O25b O16 

分 类 号：R378.21[医药卫生—病原生物学]