血流感染中大肠埃希菌对头孢吡肟耐药的危险因素分析

Risk Factor Analysis of Escherichia coli in Resistance to Cefepime in Bloodstream Infections

探讨血流感染中头孢吡肟耐药大肠埃希菌的流行病学特点及感染危险因素,为临床感染预防提供理论依据。收集2014年1月至2015年12月重庆医科大学附属第一医院血流感染标本中的71株头孢吡肟耐药大肠埃希菌作为病例组,同时选取等比例的头孢吡肟敏感大肠埃希菌作为对照组,进行病例对照研究。采用脉冲场凝胶电泳(pulsed-field gel electrophoresis,PFGE)进行分子流行病学调查,并采用卡方检验和logistic回归模型对患者病例资料进行相关危险因素分析。病例组菌株多重耐药现象严重,对喹诺酮类、氨基糖苷类、磺胺类抗生素的耐药率分别为84.5%、64.8%、77.5%,明显高于对照组;PFGE结果显示耐药菌株间不存在克隆传播现象;危险因素分析显示感染前手术史、引流管、头孢菌素类抗生素使用和产ESBLs是其独立危险因素。因此,建议医院加强该类细菌的监管和防控,减少相关侵入性操作,避免滥用抗生素,从而减少头孢吡肟耐药菌株的产生与流行。

The purpose of this study is to investigate the epidemiology and risk factors of cefepime（FEP）-resistant Escherichia coli（E. coli） from bloodstream infections, and to provide theoretical basis for infection prevention.Seventy-one cefepime-resistant Escherichia coli and equal proportion of cefepime-sensitive Escherichia coli isolates in blood specimens were collected from The First Affiliated Hospital of Chongqing Medical University from January 2014 to December 2015. The molecular epidemiology was characterized by pulsed-field gel electrophoresis（PFGE）. Chi-square test and logistic regression were performed to evaluate the related risk factors.The phenomenon of multi-drug resistance in case group strains was serious and the resistance rates of quinolones,aminoglycosides and sulfa antibiotic were 84.5%, 64.8% and 77.5%, respectively, significantly higher than those of the control group. PFGE showed there were no transmitting phenomenon among cefepime-resistant Escherichia coli isolates. Risk factor analysis showed that operation history, drainage-tube, use of cephalosporin and ESBLs-producing are the independent risk factors. Efficient supervision of nosocomial infection, fewer invasive operations and reasonable use of antibiotics would be necessary in order to prevent the emergence and transmission of cefepime-resistant Escherichia coli strains.