Study of class 1 integrons in multidrug-resistant uropathogenic Escherichia coli isolated from different hospitals in Karachi

Objective(s): Escherichia coli is the key pathogen in the family producing ESBL (extended spectrum β-lactamase) and associated with community-acquired infections. Therefore, this study was planned to determine the antibiotic susceptibility pattern of uropathogenic E. coli, prevalence of the ESBL gene group and class 1 integrons.Materials and Methods: Clinical isolates of uropathogenic E. coli were isolated from different hospitals of Karachi. Antibiotic susceptibility test was performed by Kirby-Bauer Methods. Presence of β– lactamases genes (CTX, TEM, and SHV) and integron 1 were identified by polymerase chain reaction (PCR).Results: Out of 500, 105 isolates were identified as multi-drug resistant (MDR) uropathogenic E. coli. The subject MDR isolates showed the highest resistance to aztreonam, amoxil/ clavulanic acid, ampicillin, cotrimoxazole, ceftriaxone, cefipime, and cefuroxime. Genetic analysis showed that the majority of the MDR E. coli carry CTX M1 (57.1%) followed by TEM (33.3%) and SHV (9.5%). Moreover, 79% of MDR E. coli harbored class 1 integrons, whereas all three conserved genes for class 1 integrons were present in 58% of MDR E. coli. Conclusion: This study is helpful to provide information regarding the antibiotic susceptibility pattern, distribution ESBLs and class 1 integrons among uropathogenic E. coli.