摘要
目的了解某院重症监护室(ICU)分离的多重耐药鲍曼不动杆菌(MDR-AB)Ⅰ型整合子阳性率,并分析MDR-AB的同源性,探讨Ⅰ型整合子参与耐药、传播的分子机制。方法收集2008年1月—2009年12月该ICU分离的40株MDR-AB,采用K-B纸片扩散法检测其耐药性,聚合酶链反应(PCR)进行Ⅰ类整合子可变区扩增、克隆测序,分析Ⅰ类整合子基因结构。应用脉冲场凝胶电泳(PFGE)分析MDR-AB的同源性。结果 75.00%(30/40)的菌株Ⅰ类整合子阳性,共检测出两种基因盒,分别为aacA4-catB8-aadA1和aacC1-orfX-orfX-orfX’-aad A1。PF-GE结果表明,40株菌分为4个克隆,其中有26株属于B克隆,为主要流行菌株型。结论Ⅰ类整合子在MDR-AB中广泛存在,可能通过水平传播方式在ICU中传播。携带aacA4-catB8-aadA1整合子的MDR-AB引起了ICU鲍曼不动杆菌的流行。
Objective To investigate the positive rate of class I integron in Acinetobacter baumannii （AB） isolated from an intensive care unit （ICU）, analyze the homology of multidrug-resistant AB （MDR-AB）, and explore the molecular mechanisms of class I integron involved in drug resistance and the spread. Methods Forty MDR-AB isolates from the ICU between January 2008 and December 2009 were collected, drug resistance of all isolates were detected by Kirby Bauer method, PCR and DNA sequencing were undertaken to clarify the context of gene cassette. Pulsed-field gel electrophoresis was used to analyze the homology of MDR-AB. Results Class II integron was detected in 75.00% （30/40） of all isolates, 2 types of gene cassettes were identified, namely aacA4-catB8-aadA1 and aacCl-orfX-orfX-orfX＇-aadA 1. Forty isolates were classified into 4 distinct genotypes by PFGE analysis, 26 isolates belonged to clone B that were predominant epidemic strain. Conclusion class I integrons are widespread in MDR-AB, and spread horizontally in ICU. The epidemic of AB in ICU maybe caused by MDR AB carrying aacA4- catBS-aadA 1 cassette.
出处
《中国感染控制杂志》
CAS
2012年第6期417-421,共5页
Chinese Journal of Infection Control
基金
广州市教育局创新团队科研基金(B94117)
广州市科技计划项目(2010J-E171)
关键词
鲍曼不动杆菌
抗药性
微生物
多重耐药
脉冲场凝胶电泳
重症监护室
医院感染
Acinetobacter baumannii
drug resistance, microbial
multidrug resistance
pulsed-field gel electro- phoresis
intensive care unit
healthcare-associated infection
