鲍曼不动杆菌的耐药分析及主动外排基因adeB的检测

目的了解临床分离不动杆菌属对16种抗菌药物的耐药性,为耐药菌的抗菌药物选择提供依据,并扩增外排泵蛋白编码基因adeB,以探讨鲍曼不动杆菌多重耐药与细胞膜主动外排作用的关系。方法随机收集40株不重复鲍曼不动杆菌,采用K-B法对鲍曼不动杆菌进行药物敏感试验。后采用聚合酶链反应(PCR)方法筛选鲍曼不动杆菌的主动外排基因adeB,并进行序列分析。结果 40株鲍曼不动杆菌对头孢哌酮/舒巴坦、亚胺培南最为敏感,耐药率为0;其次对氨苄西林/舒巴坦,耐药率仅为27.5%;对其余抗菌药物的耐药率在52.5%～75.0%之间;根据PCR产物片段大小,40株鲍曼不动杆菌共有adeB基因阳性菌株26株(65.0%)。序列分析显示adeB基因与参考序列AF37088599%相同,与参考序列AJ971416100%相同。结论鲍曼不动杆菌是医院感染的重要病原菌,对多种抗生素的耐药率高,且呈多重耐药。主动外排作用可能是鲍曼不动杆菌多重耐药的重要机制之一。

Analysis on Drug Resistance and Identification of Active Efflux Gene adeB in Acinetobactery baumanni

Objective To study the resistance of Acinetobacter baumanni isolated in clinical departments,and to investigate the effect of efflux inhibition of the active efflux pump gene adeB on the multi-resistance of Acinetobacter baumannii.Methods Totally 40 strains of Acinetobacter baumannii were collected from the Second Xiangya Hospital.The disk diffusion method （Kirby-Bauer） was used to determinate the sensitivities of 16 kinds of antibacterial drugs.The active efflux pump gene adeB was identified by polymerase chain reaction （PCR） and the gene was sequenced and analyzed.Results The resistant rates of Acinetobacter baumannii to cefoperazone/sulbatam and imipenem were both 0,the resistance rate to ampicillin-sulbactam was 27.5%,and the range of the resistance rates to other antibacterial drugs was from 52.5% to 75.0%.Among 40 strains of Acinetobacter baumannii,26 had adeB gene,with the detection rate of 65.0%.Compared with sequences of the active efflux pump gene adeB （NO AF370885 and NO AJ971916） in the Genbank,there were 99% and 100% identities,respectively.Conclusions Acinetobacter baumannii with high and multiple antibiotic resistances is one of the most important pathogens in nosocomial infections,and the effect of active efflux system may be one of the major mechanisms of multidrug resistance.