多药耐药鲍氏不动杆菌外排泵基因表达的研究  

Expression of efflux pump genes in multidrug-resistant Acinetobacter baumannii

作　　者：唐吉斌[1] 翁伟[1] 周东升[1] 吴志平[1] 

机构地区：[1]铜陵市人民医院检验科,安徽铜陵244009

出　　处：《中华医院感染学杂志》2011年第16期3314-3317,共4页Chinese Journal of Nosocomiology

基　　金：安徽省铜陵市卫生局科研课题资助项目〔铜卫科研(2009)016〕

摘　　要：目的探讨鲍氏不动杆菌对常用抗菌药物的耐药性及与外排泵adeA基因表达水平之间的关系。方法琼脂两倍稀释法检测鲍氏不动杆菌对17种常用抗菌药物的最低抑菌浓度(MIC);PCR法扩增外排泵编码基因adeA;实时荧光定量RT-PCR法检测adeA基因的mRNA表达水平。结果药敏结果显示,耐药率最高的是亚胺培南,其次是头孢哌酮/舒巴坦,耐药率分别为92.9%、78.8%,临床常用的氨苄西林/舒巴坦、头孢吡肟、阿米卡星、氧氟沙星及环丙沙星耐药率均>50.0%;氨曲南、哌拉西林、头孢噻肟、头孢曲松等抗菌药耐药率相对较低;85株鲍氏不动杆菌中有多药耐药株52株,占61.2%;adeA基因的检出阳性率为81.2%,实时定量RT-PCR结果显示,多药耐药菌株adeA基因的mRNA相对表达量均高于敏感菌株,其中3株相对表达量为敏感菌株平均表达水平>20倍。结论临床分离的鲍氏不动杆菌株耐药情况严重,其主动外排系统adeA基因表达增强在多药耐药性形成中起重要作用。OBJECTIVE To investigate the relationship between the antimicrobial resistance and the expression of efflux pump gene adeA in Acinetobacter baumannii.METHODS The minimal inhibitory concentrations（MIC） of 17 antimicrobial agents against 85 A.baumannii clinical isolates were determined by agar dilution method.PCR was used to amplify the adeA gene and the mRNA expression of adeA gene were quantified by real time fluorescent quantitative PCR.RESULTS Antimicrobial susceptibility test results showed that the resistance rate of imipenem was the highest which accounted for 92.9%,and followed by cefoperazone/sulbactam（78.8%）.The resistance rates were also relatively high among the antibiotics commonly used such as ampicillin/sulbactam,cefepime,amikacin,levofloxacin and ciprofloxacin which were more than 50.0%,while the resistance rates were relatively low in Aztreonam,piperacillin,cefotaxime,ceftriaxone etc.There were 52 multi-drug resistant strains in 85 strains of A.baumannii,accounting for 61.2%,81.2% of the isolates were positive for adeA.The result of RT-PCR showed that the levels of mRNA expression of adeA gene in mutidrug-resistant strains were higher compared with the susceptible ones,in which the expression of adeA gene of 3 mutidrug resistant strains were more than 20 times of the average expression level of the susceptible ones.CONCLUSION Most isolates are highly resistant to most of the antibacterial agents commonly used.High levels of mRNA expression of adeA gene in Acinetobacter baumannii play an important role in multidrug resistance.

关 键 词：鲍氏不动杆菌 主动外排系统 多药耐药 实时荧光定量RT-PCR 

分 类 号：R378[医药卫生—病原生物学]