Detection of OXA Beta Lactamases Among Clinical Isolates of Acinetobacter baumannii Isolated from Tehran Hospitals, Iran

Abstract

Background and Objective:Acinetobacter baumanniiis a non-motile Gram-negative bacterial pathogen with the history of vast resistant to antibiotics. The aim of this study was to determine the possibility of existence of OXAs genes among clinical isolates ofA. baumanniiobtained from Tehran hospitals.Materials and Methods:A total of 101 isolates were identified asA. baumanniiby common biochemical and molecular tests. The susceptibility to different antibiotics was assessed with Kirby-Bauer disk diffusion method. Phenotypic Detection of MBLs was performed with CDT test and PCR assay was also performed for detection ofblaOXA-23-like,blaOXA-24-like,blaOXA-40-like,blaOXA-51-like,blaOXA-58-likeandblaOXA-143-likegenesResults:All isolates ofA. baumanniishowed high-level of resistance to all antibiotics except for Polymyxin B. TheblaOXA-51 likegenes was found in all of the isolates and the prevalence ofblaOXA-143like,blaOXA-23like,blaOXA-40likeandblaOXA-24likewere 56%, 45.45%, 33% and 11.8%, respectively.Conclusion:TheblaOXA-51-likewas the predominant mechanism of resistance to imipenem inA. baumanniiand therefore, early recognition of carbapenem-resistantA. baumanniiisolates is a useful tools to prevent their spreading within the hospital environment.