Prevalence of Extended-spectrum ß-lactamases among Acinetobacter Baumannii Strains Isolated from University Hospitals of Qazvin, Iran

Background and Aim : Acinetobacter baumannii is a major cause of health care-associated infections. Extended-spectrum beta-lactamase (ESBL)-producing A. baumannii is spreading worldwide. We aimed to determine the frequency of ESBL encoding genes in clinical isolates of A. baumannii and to access their clonal relationship by repetitive extragenic palindromic-PCR (rep -PCR).Methods : In this descriptive cross-sectional study, ۲۰۳ isolates of A. baumannii were collected from Qazvin teaching hospitals. These isolates were identified using standard laboratory methods and by detection of the intrinsic blaOXA-۵۱-like and gltA genes. To verify ESBL production, all isolates were screened by disk agar diffusion and confirmed using the combined disk method. Subsequently, ESBL encoding genes were isolated by PCR and sequencing. Possible clonal association of ESBL-producing isolates was evaluated by rep-PCR.Results : In total, ۲۰۰ (۹۸.۵%) isolates showed reduced susceptibility to one of the antibiotics used in the ESBL screening test, of which ۱۲۷ isolates (۶۲.۶%) produced ESBL. PCR results showed that ۲۶ (۲۰.۵%) isolates carried the blaOXA-۱ gene as the most common gene followed by blaTEM-۱ (۲۰%), blaGES-۱ (۱۵.۷%), and blaCTX-M-۱۵ (۷.۹%), and blaPER-۱ (۱.۶%). Rep-PCR results showed that ESBL-producing isolates belonged to three distinct clones A (۸۵%), B (۱۳.۴%), and C (۱.۶%).Conclusion : The findings of this study showed the significant presence of blaOXA-۱, blaTEM-۱, blaGES-۱, and blaCTX-M-۱۵, and blaPER-۱ genes in ESBL-producing A. baumannii isolates in the studied hospitals. This is the first report of the presence of blaOXA-۱ gene in these isolates in Iran. The use of comprehensive antimicrobial treatment guidelines based on laboratory data and appropriate infection control strategies to prevent further infection by these organisms are essential.

کلیدواژه ها:

Acinetobacter baumannii ، ESBLs ، repetitive extragenic palindromic-PCR