Determination of Antibiotic Resistance Pattern and Prevalence of Oxa-Type Carbapenemases Among Acinetobacter Baumannii Clinical Isolates From Inpatients in Isfahan, Central Iran Pubmed



Rezaei A¹ ; Fazeli H¹ ; Moghadampour M¹ ; Halaji M¹ ; Faghri J¹ Show Affiliations
Source: Infezioni in Medicina Published:2018

Abstract

Acinetobacter baumannii is one of the most important bacterial species with the ability to produce OXA-type carbapenemases. We aimed to evaluate the prevalence of OXA-type carbapenemases among clinical isolates of A. baumannii in three major hospitals of Isfahan. In this cross-sectional descriptive study, 153 non-repeated strains of A. baumannii were isolated from various clinical samples of hospitalized patients in Al-Zahra, Imam Mousa Kazem, and Shariati hospitals from October 2015 to October 2016. Antimicrobial susceptibility testing for imipenem, meropenem, ertapenem, cefepime, ceftazidime, ceftriaxone, piperacillin-tazobactam, gen-tamicin, amikacin, ciprofloxacin, and tetracycline was performed using the disk diffusion method. In order to identify blaOXA genes, a multiplex polymerase chain reaction was used. The resistance rates in A. baumannii isolates to beta-lactam antibiotics including imipenem, ertapenem, meropenem, cefepime, ceftazidime, ceftriaxone, and piperacillin/tazobactam were 100%, 100%, 99.3%, 97.4%, 96.7%, 97.4%, and 98.6%, respectively. PCR assay showed the presence of blaOXA genes in all isolates. The blaOXA-51 gene was recognized in all (100%) isolates, 90.8% and 62.1% of isolates possessed the blaOXA-23 and blaOXA-24 genes, respectively, while the bla-gene was not detected in any of the isolates. Also, 56.2%OXA-58 of isolates had both the blaOXA-23 and blaOXA-24 genes simultaneously. We found that the prevalence of OXA-type carbapenemases among carbapenem-resistant A. baumannii isolates is high in Isfahan, with OXA-23 being the major carbapenemase mechanism responsible for the resistance phenotype. © 2018, EDIMES Edizioni Medico Scientifiche. All rights reserved.