大肠埃希菌毒力因子检测及其与耐药相关性研究

Detection of virulence genes of Escherichia coli and its drug resistance

目的探讨不同来源大肠埃希菌毒力因子的分布及其与耐药性的关系。方法对2003-2008年温州医学院附属第一医院的住院患者不同标本中分离的188株大肠埃希菌用PCR方法扩增毒力因子papC、sfa/foc、afa/dra、hly、cnf1、iutA、aer、fimH、kpsMTⅡ、fyuA。采用VITEK-60自动化微生物分析仪检测大肠埃希菌对常用抗菌药物的敏感性。结果毒力因子iutA、fyuA在不同标本来源的大肠埃希菌中的检出率较高,均>50%,毒力因子aer、fimH在不同标本来源的大肠埃希菌中的检出率差异无统计学意义(P<0.05)。氨苄西林的耐药性与毒力因子aer有关(P<0.05),喹诺酮类抗菌药物环丙沙星,左旋氧氟沙星的耐药性与毒力因子iutA有关,头孢唑啉的耐药性与afa/dra有关,庆大霉素的耐药性与aer有关,复方新诺明的耐药性与sfa/foc、iutA、aer有关,头孢他啶的耐药性与sfa/foc、iutA有关,氨苄西林/舒巴坦的耐药性与aer有关(P<0.05)。结论毒力因子在不同来源大肠埃希菌中的分布有差异,某些毒力因子与大肠埃希菌耐药性相关,应引起临床重视。

Objective To understand the distribution of virulence genes of Escherichia coli（E.coli） from different sources and the relationship with the drug resistance.Methods PCR was applied to amplify virulence genes of papC,sfa / foc,afa / dra,hly,cnf1,iutA,aer,fimH,kpsMT Ⅱ and fyuA in 188 E.coli strains isolated from different samples of hospitalized patients in our hospital from 2003 to 2008.VITEK-60 AMS was used to test susceptibility of E.coli to common used antibiotics.Results The detection rate virulence genes iutA and fyuA was more than 50%.The difference on the detection rate of aer and fimH in different samples was statistical significant（P〈0.05）.The resistance to ampicillin was related with virulence gene aer（P〈0.05）;Additionally,the resistance to quinolone（ciprofloxacin,levofloxacin） was related with iutA（P〈0.05）,the resistance to cefazolin was related with afa / dra,the resistance to gentamicin was related with aer,the resistance to cotrimoxazole was related with sfa / foc,iutA,aer,the resistance to ceftazidime was related with sfa/foc,iutA,and the resistance to ampicillin/sulbactam was related with aer（P〈0.05）.Conclusion The distribution of virulence genes of E.coli varied by different samples.Some virulence genes were related with drug resistance of E.coli,close attention should paid on it.