Background: Efflux pumps are involved in resistance of Acinetobacter baumannii isolates to antimicrobial agents. AdeABC efflux pump is one of the RND superfamily efflux pump and consists of adeA (membrane fusion), adeB (multidrug transporter) and adeC (outer membrane) genes. In this study, the frequency of adeA, adeB and adeC genes among A. baumannii isolates with resistance to erythromycin, trimethoprim, meropenem and imipenem was investigated. Methods: Overall, 79 strains of A. baumannii were isolated from patients admitted to two major hospitals in Tehran during 2016. Antibiotic susceptibility testing was determined by disc diffusion and microdilution methods according to Clinical and Laboratory Standards Institute (CLSI) guideline. The presence of adeA, adeB and adeC genes was also determined using Multiplex PCR assay. Results: The highest and the lowest resistance among A. baumannii isolates were to trimethoprim (93%) and erythromycin (53%), respectively. The frequency of adeA, adeB and adeC genes was 96.2%, 96.2% and 91.1 % respectively. There was a significant relationship between imipenem resistance and presence of efflux pump genes (P<0.05). Conclusion: According to the high prevalence of the AdeABC efflux system genes, it may involve in resistance of clinical isolates of A. baumannii to imipenem, especially.

中文翻译：

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鲍曼不动杆菌分离株中 AdeA、AdeB 和 AdeC 基因的高频率


背景：外排泵参与鲍曼不动杆菌分离株对抗菌药物的耐药性。 AdeABC外排泵是RND超家族外排泵之一，由adeA（膜融合）、adeB（多药转运蛋白）和adeC（外膜）基因组成。本研究调查了对红霉素、甲氧苄啶、美罗培南和亚胺培南耐药的鲍曼不动杆菌中 adeA、adeB 和 adeC 基因的频率。方法：总体而言，从 2016 年德黑兰两家主要医院收治的患者中分离出 79 株鲍曼不动杆菌。根据临床和实验室标准研究所 (CLSI) 指南，通过纸片扩散和微量稀释方法测定抗生素敏感性测试。还使用多重 PCR 测定法确定了 adeA、adeB 和 adeC 基因的存在。结果：鲍曼不动杆菌耐药性最高和最低的分别是甲氧苄啶（93%）和红霉素（53%）。 adeA、adeB和adeC基因的频率分别为96.2%、96.2%和91.1%。亚胺培南耐药性与外排泵基因的存在之间存在显着关系（P<0.05）。结论：AdeABC外排系统基因的高患病率可能与鲍曼不动杆菌临床分离株对亚胺培南的耐药有关。