Molecular characterization of quinolone resistant spp. isolates from patients in Ardabil, Iran.

Background And Objectives: is an etiological agent of shigellosis. Antibiotic therapy has a critical role in decreasing serious complications of shigellosis. The present study aimed to determine the multi-drug resistance strains and to detect fluoroquinolone related mutations.

Materials And Methods: In this descriptive, cross sectional study, a total of 113 isolates were collected from 1280 patients admitted to Bu-Ali hospital in Ardabil province during 2015-17. Antibiotic resistance pattern of isolates was evaluated using Kirby Bauer method and finally, the MICs of ciprofloxacin were determined. In order to determine any mutations in QRDR region, and genes of resistant strains were amplified and sequenced.

Results: spp. isolates were identified using amplification and and genes were used for molecular detection of and , respectively. Our results showed that the predominant species in Ardabil province was (69.91%). Most of isolates (82%) were resistant to trimethoprim/sulfamethoxazole (TMP/SMX); 51% were nalidixic acid resistant and 4.4% were floroquinolones resistant. All examined isolates were susceptible to imipenem (100%). Mutation in and genes were detected in all fluoroquinolone resistant isolates (5 isolates). Although, in this study the rate of resistance to ciprofloxacin was low, but in the lack of preventive strategy it will be a major challenge of public health in future.

Conclusion: This study provided information on the prevalence and antimicrobial susceptibility patterns of isolates in Ardabil province, Iran. Also this study showed a high-level of resistance to commonly used antibiotics among isolates.