Detection of bla SHV, sul۲ and aadA genes among Escherichia coli clinical strains isolated from Bu-Ali and Amiralmomenin hospitals in Tehran by PCR

Background and Aim : Background and Aim: E.coli is one of the most commonly pathogens isolated from urinary tract infections. Unfortunately, antibiotic resistance has become increasingly as a pressing clinical issue in many countries. The aims of this study were to determine the antimicrobial susceptibility pattern and prevalence of bla SHV, sul۲ and aadA genes in E.coli strains obtained from Bu-Ali and Amiralmomenin hospitals in Tehran.Methods : Methods: One hundred clinical Escherichia coli isolates were collected from Bu-Ali and Amiralmomenin hospitals in Tehran. After identification of Escherichia coli isolates by biochemical tests, antibiotic susceptibility was done using the Kirby-Bauer disk diffusion method according to Clinical and Laboratory Standards Institute (CLSI, ۲۰۱۹). PCR were applied for detection of bla SHV, sul۴ and aadA genes among the antibiotic resistant isolates.Results : Results: The results of this study showed high antibiotic resistance among of the isolates. The highest resistance of E.coli isolates was seen to piperacillin (۸۷%) and carbenicillin (۹۲%). The resistant rates to various other antibiotics were as follows: ceftazidime (۵۳%), cefotaxime (۶۰%), ceftriaxone (۵۷%), cotrimoxazole (۵۵%), gentamicin (۴۰%), nalidixic acid (۶۷%), ciprofloxacin (۷۳%), streptomycin (۲۷%), and chloramphenicol (۶۵%), respectively. Of ۵۵ cotrimoxazole resistant isolates, ۴۴ (۸۰%) strains contained sul۲ gene. The frequency of aminoglycosides resistance gene including aadA in streptomycin and gentamicin resistant isolates were (۴۰%).The prevalence of blaSHV in piperacillin and carbenicillin resistance was ۶۵.۷۱%.Conclusion : Conclusion: This study detected clinical E.coli isolates harboring antibiotic resistance genes. Determination of antibiotic susceptibility patterns of E.coli against antibiotic and study of related genes are necessary for elucidating molecular and epidemiological mechanisms of resistance.

کلیدواژه ها:

Key words: Escherichia coli ، Antibiotic resistance ، bla SHV ، sul۲ ، aadA