87株多重耐药鲍曼不动杆菌多位点序列分型

目的 了解安徽地区近年来临床分离的多重耐药鲍曼不动杆菌的耐药性、菌群结构和流行菌株,分析其基因同源性及亲缘进化关系,为临床抗菌药物应用提供一定的实验室依据.方法 收集安徽地区临床分离的多重耐药鲍曼不动杆菌87株,采用琼脂稀释法测定其对11种临床常见抗菌药物的最小抑菌浓度.通过多位点序列分型方法,反映菌株间进化关系,利用BioNumerics软件构建聚类图,从而进行基因分型.结果 87株鲍曼不动杆菌对亚胺培南、美罗培南的耐药率分别为74.7％、66.7％,对其他常用抗菌药物耐药率都很高.其分为42个ST型,其中6个型别是数据库里原来有的,36个型别为新的型别(暂时命名为STnew01～ST-new36).ST2包含37株菌,是优势型别,其属于克隆复合体CC1.结论 多重耐药鲍曼不动杆菌对11种常见临床抗菌药物均呈现出较高的耐药率,ST2为安徽地区多重耐药鲍曼不动杆菌主要的流行克隆,安徽地区主要的流行株ST2与世界上主要的流行克隆具有高度的同源性.

Multilocus sequence typing of 87 strains of multidrug-resistant Acinetobacter baumannii

Objective To obtain knowledge of microbial colonial structures and epidemic strains of clinically isolated multidrug-resistant Acinetobacter baumannii in Anhui in recent years.To analyze gene homologies and phylogenetic relationships of multidrug-resistant Acinetobacter baumannii.To provide some laboratory data for clinical antimicrobial application.Methods Eighty-seven strains of clinically isolate dmultidrug-resistant Acinetobacter baumannii were collected in this study,and the minimal inhibitory concentrations of these strains to 11 common antimicrobials were measured by agar dilution.Evolutionary relationships between the strains were revealed with employment of multilocus sequence typing,and clustering figures were constructed with the aid of the BioNumerics software,thus enabling genotyping.Results The drug-resistance rates of 87 strains of Acinetobacter baumannii to imipenem and meropenem were 74.7％ and 66.7％,respectively,while the drug-resistance rates to other antimicrobials were considerably high.All the 87 strains were sub-divided into 42 ST-types,6 of which were already involved in the database while 36 (temporarily named STnew01 ～STnew36) were newly established.Thirty-seven strains were proved dominant types and sub-listed in the ST2 category.The ST2 Acinetobacter baumannii belongs to the clone complex CC1.Conclusion All multidrug-resistant Acinetobacter baumannii in research show high drug-resistance rates when treated with 11 common antimicrobials.The ST2 category is the principal epidemic clones of multidrug-resistant Acinetobacter baumannii in Anhui province,and a highly recogonizable homology is observed between the principal epidemic strains(ST2) in Anhui and those in the world.