Molecular typing of Acinetobacter baumannii complex isolated from clinical samples in west of Iran

Background and ObjectivesAcinetobacter baumannii is a multi-drug resistant gram-negative organism. Due to the increasing number of A. baumannii infections in hospitals, molecular genotyping can provide information to identify the principles of the epidemiological spread of this microorganism. The present study was conducted to investigate the antibiotic resistance of A. baumannii complex clinical strains isolated from intensive care units (ICUs) of hospitals in Sanandaj and Kermanshah cities and to determine the genetic relationships between isolates.Material and MethodsIn this cross-sectional study, ۷۵ A. baumannii complex strains were isolated from various clinical specimens of patients hospitalized in the ICUs of three hospitals in Sanandaj and Kermanshah, in west of Iran during six months. The antibiotic susceptibility was determined by the disk diffusion agar method. Metallo-beta-lactamase producing strains were identified using the PCR method. ERIC-PCR and Multilocus Sequence Typing (MLST) were used to determine the genetic relationships between isolates. The nucleotide sequences of seven housekeeping genes were analyzed in the Pasteur Pub-MLST database and the genetic relationships of the isolates were determined.Results and DiscussionThe highest level of resistance was found to Cefotaxime (۹۹%), Ciprofloxacin (۸۹%), Meropenem (۸۸%), and Gentamicin (۸۷%). The lowest resistance was found to Tetracycline (۵۹%). A total of ۸۹% of the strains was multidrug-resistant (MDR). PCR indicated that ۶۵ isolates (۸۷%) carried the blaVIM gene, while none of the isolates carried blaSIM, blaGIM, blaNDM, blaIMP and blaSPM. ERIC typing and MLST showed a clonal spread of isolates in the hospitals in Sanandaj and Kermanshah. The sequence type (ST) ۴۱۵ was obtained.ConclusionThis study demonstrated a high level of resistance and clonal dissemination of A. baumannii isolated from patients hospitalized in the ICUs of hospitals in Sanandaj and Kermanshah. The increasing prevalence of hospital infections and the emergence of resistance among A. baumannii isolates highlight the need to investigate the genetic diversity between isolates. The present study can aid in developing methods to control the spread of this pathogen.

کلیدواژه ها:

Acinetobacter baumannii ، Metallo-beta-lactamase ، Antibiotic resistance ، blaVIM gene ، Multilocus sequence typing