The Frequency of Beta Lactamase genes in Escherichia coli isolates from outpatient suffering from urinary tract infections in Guilan province

Escherichia coli is one of the most common causative agent of urinary tract infection. In recent years, resistance to cephalosporins has been considerably on the rise due to production of extended spectrum beta-lactamases (ESBLs.( This study was aimed to determine the survey of CTX-M, SHV, TEM, OXA-1, PER-2, and VEB-1 which are the most famous ESBL genes in E. coli isolated from outpatients with UTI in Guilan.
A total of 2267 urine samples were collected from outpatients suffering from UTIs. After primary biochemical and differential tests like MRVP, Lysin dacarboxilation in LIA medium, Urea hydrolysis test, TSI and Simon citrate test, samples containing E. coli were identified. Antibiotic susceptibilities were determined by disk diffusion. Double disk tests using Cephtriaxon, Amoxiclave and Cephtazidime-clavolonate were performed for phenotypic ESBL production assay. ESBL-producing genes were evaluated by PCR.
Among the 2267 urine samples, 167 E. coli cells were isolated. From these E. coli isolates, 38.9% were shown to be ESBL producers by the Double disk method. Based on the molecular analysis, the frequency of ESBL-producing genes were, CTX-M (70.32%), TEM (9.64%), SHV (4.88%) OXA-1 (57.2%), and PER-2 (12.1%). VEB-1 was not detected in the analyzed samples. Also, some of the isolates had more than one ESBL-producing gene. Statistically, there was a direct correlation between gender and age with the infection.
In this study, more than half of the isolated bacteria were ESBL-producers. As the resistance-inducing genes are carried on mobile genetic elements, rapid detection of resistant species is of major importance to prevent their dissemination.