Diversidade genômica de isolados nosocomiais de actinetobacter baumannii multirresistentes produtores de carbapenemases em hospitais de ensino do Ceará

Abstract

Acinetobacter baumanniiis an opportunistic pathogen resistant to several antimicrobials. We aimed to investigate the sensitivity profile and frequency of OXA-type carbapenemases among A. baumannii nosocomial strains isolated from patients in teaching hospitals of Ceará, Brazil.From November 2016-April 2017, A. baumannii nosocomial strains from four teaching hospitals were analyzed. All isolates were identified, and the antimicrobial susceptibility profile established by VITEK®2. Polymerase chain reaction (PCR) to amplify the bla OXA-51 gene was performed on all presumptively strains identified as A. baumannii, and minimum inhibitory concentrations were determined by the broth microdilutionfor tigecycline-resistant isolates. Furthermore, bla OXA-23 , bla OXA-24 , and bla OXA-58 genes were detected by PCR. A total of167 A. baumannii nosocomial strains were analyzed, from which 101 (60.5%) were from patients in intensive care units, 54 (32.3%) were isolated from thebloodstream, and 142 (85.0%) were multi-drug resistant (MDR). 132 (79.0%) isolates were resistant to carbapenems, but all isolates were susceptible to colistin and most of them were susceptible to tigecycline. The majority harbored the bla OXA-23 gene, these data were significantly associated with an MDR phenotype. In addition, 45 (26.9%) contained bla OXA-24 , four strains harbored concomitantly bla OXA-23 and bla OXA-24 and nobla OXA-58 geneswere detected.These results demonstrated high resistance rates to the different antimicrobial drugs analyzed and a high frequency of bla OXA-23 gene, suggesting that colistin and tigecycline could be the therapeutic options for the treatment of infections associated with MDRA. baumannii.