Antibiotic susceptibility pattern and ESBL prevalence in nosocomial Escherichia coli from urinary tract infections in Pakistan

Urinary tract infections (UTI) are the most prevalent infections worldwide, mostly caused by Escherichia coli. These bacteria also produce enzymes called extended spectrum b-lactamases (ESBL) which render penicillins and cephalosporins inactive. The present study included 116 E. coli, isolated from urine of in-patients suffering from UTI. Antibiotic susceptibility testing and ESBL detection were carried out according to Clinical Laboratory and Standards Institute (CLSI) criteria. Fifteen antibiotics were tested in this study. A total of 66 (56.9%) isolates were found to be ESBL producers. A total of 83% isolates were resistant to 4 or more antibiotics. Imipenem and meropenem showed high potency with 98 and 97% isolates being susceptible, respectively. Susceptibility to gentamicin was 48%, kanamycin 43%, both ofloxacin and enoxacin 38%, ciprofloxacin 35%, doxycycline 18% and to co-trimoxazole only 17%. This study reveals that E. coli isolated from UTI in this region are multi-drug resistant and produce ESBL in large proportions.