多药耐药鲍氏不动杆菌氨基糖苷类修饰酶基因分子类型分析

Types of Aminoglycoside-modifying Enzyme Genes of Multidrug-resistant Acinetobacter baumannii

目的探索多药耐药鲍氏不动杆菌(MDR-ABA)氨基糖苷类药物修饰酶基因(AMEs)分子类型。方法采用K-B药敏法测定2007～2008年临床分离的MDR-ABA对庆大霉素、妥布霉素、阿米卡星的药敏表型,筛选出43株对氨基糖苷类药物耐药的菌株,以聚合酶链反应(PCR)的方法对7种AMEs进行检测和分析。结果 43株MDR-ABA对庆大霉素的耐药率为90.7%,对阿米卡星的耐药率为60.5%,对妥布霉素的耐药率为72.1%;7种AMEs检出率由高到低分别为:aac(3)-Ⅰ(65.1%)、aac(6′)-Ⅰ(60.5%),ant(3″)-Ⅰ(55.8%),aph(3′)-Ⅵ(51.2%),aac(3)-Ⅱ(34.9%),ant(2″)-Ⅰ(20.9%),aac(6′)-Ⅱ(18.6%),总检出率为90.7%。结论临床分离的MDR-ABA对氨基糖苷类抗菌药物耐药主要由AMEs引起。

OBJECTIVE To investigate the types of aminoglycoside-modifying enzyme genes（AMEs）of multidrug-resistant Acinetobacter baumannii（MDR-ABA）.METHODS The clinical isolates of MDR-ABA were collected from 2007 to 2008,and their resistance to gentamicin,amikacin and tobramycin was tested by K-B method.Forty-three isolates were chosen because of their resistance to aminoglycoside antibiotics（at least resistant to one kind of the drugs）.Seven types of the AMEs were detected by PCR.RESULTS The drug-resistant rates of 43 isolates of A.baumannii to gentamicin,amikacin and tobramycin were 90.7%,60.5% and 72.1%,respectively.The detection rates of the seven AMEs,including aac（3）-Ⅰ,aac（6＇）-Ⅰ,ant（3″）-Ⅰ,aph（3＇）-Ⅵ,aac（3）-Ⅱ,ant（2″）-Ⅰ,and aac（6″）-Ⅱ,were 65.1%,60.5%,55.8%,51.2%,34.9%,20.9%,and 18.6%,respectively.The total detection rate of AMEs was 90.7%.CONCLUSIONS The resistance to aminoglycoside antibiotics of MDR-ABA is mainly caused by AMEs.