پراكندگي ژن qnrA در ايزوله هاي اشريشيا كلي مقاوم به فلوروكينولون جدا شده از ادرار بيماران مراجعه كننده به بيمارستان امام خميني(ره) تهران

Frequency of qnrA Gene among Fluoroquinolones Resistant E.coli Isolates from Urine of Imam Khomani hospital’s patients

Abstract Back ground and objective: This study was done to determine the recent resistance rate of E.coli strains isolated from urinary tract infections of patients of Imam khomanin hospital to common antibiotics especially quinolons and screening the frequency of qnrA gene among them. Materials and methods: During 6 months, 100 E.coli strains collected randomly from urine samples. All confirmed based on bacteriologic tests and their sensitivity to common antibiotics were determined based on CLSI 2011 protocol. Continuously, DNA extraction was done and frequency of qnrA gene was determined by PCR. Results: Based on antibiogram, their resistant was 100% to amoxicillin and penicillin, 77% to amoxiclauve, 72% to ceftazidim, 69% to cephotaxim, 51% to ciprofloxacin, 47% to cefexim, 46% to ceftriaxone, 43% to cephalexin, 27% to axtreonam, 14% nalidixic acid and 2% to imipenem. Among 39.5% of E.coli isolated a 516bp band related to qnrA was detected by PCR. Conclusion: Doing antibiogram in all clinical laboratories as a simple and cheap test before any antibiotic prescription especially quinolons to prevent drug resistant is recommended.