Prevalence of antibiotic resistance and related genes in clinical isolates of Stenotrophomonas maltophilia in the North of Iran

Background and Aim : Stenotrophomonas maltophilia has emerged as an important opportunistic nosocomial pathogen due to its intrinsic and acquired resistance to a wide range of antimicrobial agents. The present study aimed to investigate the occurrence of antibiotic resistance and resistance mechanisms among clinical isolates of S. maltophilia from Iranian patients.Methods : This cross-sectional study was performed on ۶۰ S. maltophilia isolates that were recovered from different clinical specimens during ۲۰۱۹-۲۰۲۰ in Tehran. Conventional microbiologic methods were used for primary identification of isolates and confirmed by specific polymerase chain reaction (PCR) primers. Minimum inhibitory concentrations (MICs) were determined by the E-test. PCR was applied to determine antibiotic resistance genes.Results : Sixty clinical isolates of S. maltophilia were obtained in this study that most of them isolated from Intensive Care Units (ICU) with ۹۰% (n=۵۴). Antibiotic susceptibility results revealed that ۱۵% of isolates were resistant against minocycline followed by ۳۰% intermediate-resistant. Moreover, MIC results showed that the resistant rates of isolates toward ceftazidime, cotrimoxazole and levofloxacin were ۴۶.۷%, and ۱.۷% and ۵%, respectively. PCR amplification of integrons gene showed that fifteen (۲۵%) of isolates carried int۱. Moreover, the prevalence of antibiotic resistance genes sul۱, sul۲, and Smqnr were found in ۱۵ (۲۵%), ۶ (۱۰%), and ۲۸ (۴۶.۷%) isolates, respectively. Conclusion : In summary, the prevalence of sul and Smqnr genes in integrons-contained isolates point out the significant risk of sulfonamides and fluoroquinolones resistance among clinical isolates of S. maltophilia in our region.

کلیدواژه ها:

Stenotrophomonas maltophilia ، Drug resistance ، integron genes ، Guilan