Background: Acinetobacter baumannii is one of the commonly encountered organisms in health care associated infections, posing a challenge in treatment due to multiple antibiotic resistance mechanisms. One of these mechanisms is the efflux pump. Three known Acinetobacter Drug Efflux pumps (Ade) belong to the Resistance Nodulation and Cell Division (RND) family are identified. The efflux pump adeABC is detected in about 80 % of clinical isolates in some reports, leading to resistance to many antibiotics.
Aim: This study aims to assess the frequency of efflux pump-encoding genes (adeA and adeS) in isolates of Acinetobacter baumannii detected among patients admitted to Ain Shams University Hospitals and to correlate their frequency with susceptibility to different classes of antibiotics. Methods: Eighty-four clinical isolates of Acinetobacter baumannii retrieved from Main Microbiology Laboratory, Ain Shams University Hospital, Cairo, Egypt, were included in the study. Identification was performed using conventional microbiological methods and antimicrobial sensitivity testing was performed. All isolates were subjected to molecular detection of adeA and adeS genes by conventional PCR. Results: The distribution of the adeA gene among clinical isolates was 78.5% and for adeS genes was 72.6% and both genes were present together in 72.6% of the tested isolates. There was a statistically significant association between the presence of adeA and adeS gene and resistance to imipenem, meropenem, ciprofloxacin, levofloxacin, and amikacin. Conclusion: The presence of adeA and adeS genes could have a pivotal involvement in resistance among A. baumannii isolates to several antibiotics.