整合子在鲍曼不动杆菌耐药中的作用研究

The effect of integron on the drug-resistant of Acinetobacter baumannii

目的调查本院鲍曼不动杆菌耐药谱并了解其整合子流行情况;检测鉴定整合子类型并分析其与耐药的相关性。方法收集本院2007年临床分离鲍曼不动杆菌85株,KB法测定其药敏结果。PCR法扩增整合子的整合酶基因,并进一步鉴定整合子种类。分析鲍曼不动杆菌整合子携带与其耐药之间的关系。PCR法扩增整合子开放阅读框,观测其多态性并挑选个别产物测序。结果 85株鲍曼不动杆菌除对亚胺培南、头孢哌酮/舒巴坦耐药率低于10%,其他15种常用抗菌药物的耐药率均超过30%。67.1%(57/85)的鲍曼不动杆菌中检出整合子;进一步鉴定结果显示均为Ⅰ类整合子,未检出Ⅱ类和Ⅲ类整合子。携带整合子鲍曼不动杆菌株对14种抗菌药物耐药率高于不携带整合子鲍曼不动杆菌株耐药率。开放阅读框可变区扩增产物为0.3～2.5 KB不等条带,测序结果证实含有多药耐药基因编码。结论本院鲍曼不动杆菌耐药率高,以多药耐药菌株为主,携带Ⅰ类整合子率较高;携带整合子鲍曼不动杆菌对14种抗菌药的耐药率明显增高,整合子与鲍曼不动杆菌的多重耐药性具有密切相关性。

Objective To investigate the drug-resistant status of Acinetobacter baumannii in clinical strains isolated from our hospital,and get to know the distribution of integrons carried by Acinetobacter baumannii,analyze the correlation between integron and drug-resistant of Acinetobacter baumannii..Methods Collected 85 Acinetobacter baumannii isolated in our lab,the drug-sensitivity tests were completed by the method of KB,the integrase genes were amplified by polymerase chain reaction（PCR）,and identified the type of integron..Analyzed the correlation between the drug-resistant and integron in Acinetobacter baumannii..The open reading frame of integron were amplified by PCR,the polymorphism of integron was identified,and sequenced the PCR products.Results Except for Imipenem and Cefoperazone/ sulbactam（drug resistant rate less than 10%）,the drug resistant rate of other 15 antibacterial was no more than 30% among the 85 Acinetobacter baumannii isolated in our lab..66.1 %（57/85） stains carried the integrons I,we didn＇t find out the integron Ⅱ and Ⅲ.The drug-resistant rates of Acinetobacter baumannii with integron were higher than that of Acinetobacter baumannii without integron.The length of amplified products in variable region of open reading frame of integron varied from 03 to 25kb,.The sequencing results confirmed the integron included multidrug resistant gene code.Conclusion In our hospital,the drug-resistant rate of Acinetobacter baumannii was high,and the majority were multidrug resistant strains.The drug-resistant rate of Acinetobacter baumannii was enhanced with integron,The multidrug resistant of Acinetobacter baumannii was associated with integrons.