亚胺培南耐药鲍曼不动杆菌分子流行病学及耐药基因研究  

Research on molecular epidemiology and resistance genes of carbapenems resistant Acinetobacter baumannii

作　　者：龚燕飞 曾强 刘湘林 张组萍[2] 陈中湘 彭华 

机构地区：[1]岳阳市第一人民医院检验科,湖南岳阳414000 [2]中南大学湘雅医学院

出　　处：《实用预防医学》2014年第1期28-31,共4页Practical Preventive Medicine

基　　金：湖南省科技计划项目(项目编号:2011SK3040)

摘　　要：目的探讨岳阳市第一人民医院耐碳青霉烯类鲍曼不动杆菌(CRAB)的分子流行病学特征,以及碳青霉烯酶基因在介导CRAB对碳青霉烯类药物耐药性形成中的作用。方法收集岳阳市第一人民医院分离的CRAB共65株,其中对亚胺培南耐药鲍曼不动杆菌(IRAB)38株,亚胺培南敏感鲍曼不动杆菌(ISAB)27株。采用琼脂稀释法检测上述细菌对15种抗菌药物的最低抑菌浓度(MIC),改良Hodge试验筛查碳青霉烯酶;PCR扩增碳青霉烯酶基因;脉冲场凝胶电泳(PFGE)分析菌株同源性。结果在检测的15种药物中,敏感性最高的药物为多黏菌素B。IRAB与ISAB组除对头孢西丁、多黏菌素B耐药性较一致外,对其他抗菌药物耐药性差异均有统计学意义(P<0.05);改良Hodge试验阳性率为66%(43/65),其中38株IRAB中,阳性36株,27株ISAB中,阳性4株;38株IRAB有32株携带OXA-23基因,ISAB组菌株中均未检测到OXA-23基因;65株菌主要分为6型,A型52株,是主要的流行克隆。结论本院存在CRAB的流行,主要为A型株。OXA-23基因的产生在介导CRAB碳青霉烯药物耐药中发挥作用。Objective To investigate the molecular epidemiological characteristics of carbapenemases resistant Acinetot）acter baumannii （CRAB） in the First People＇s Hcxspital of Yueyang and the main resistance mechanisms mediated by earbapenemase genes. Methods Sixty - five CRAB were collected in the First People＇ s Hospital of Yueyang, including 38 imipenem resis- tant Acinetobacter baumannii （IRAB） and 27 imipenem sensitive Acinetobacter baumannii （ISAB）. Their minimum inhibitory concentrations （MIQ） to 15 antibiotics were determined by agar dilution method and carhapenemase was screened by a m（x.tified Hodgc test. PCR was used to amplify carbapencmase genes. The homology was analyzed by pulse- field gel electrophoresis （ PF- GE） . Results Acinetobacter baumannii were the most sensitive to polymyxin B among 15 antimicrobial agents . IRAB and ISAB were the same resistant to cefoxitin and polymyxin B, but the resistant rates to other antibiotics in IRAB group was signifi- cantly higher than thorn in the ISAB group （P〈0.05）. 43 positive strains were detected by the modified Hodge test in 65 Aci- netabacter baumannii, with 36 positive strains from 38 IRAB and 4 from 27 ISAB. 32 strains of 38 IRAB carried OXA - 23 gene, while none ISAB carried it. 65 Acinetobacter baumannii strains were classified into 6 types based on their PFGE pulse types, with ty-pe A （ 52 strains） as the major clone. Conclusions There is an endemic of CRAB in the hospital, with type A as the major clone. OXA- 23 gene may play a role in the carbapenems resistance mechanism of Acinetobacter baumannii.

关 键 词：鲍曼不动杆菌 碳青霉烯酶基因 脉冲场凝胶电泳 分子流行病学特征 

分 类 号：R378[医药卫生—病原生物学]