Molecular prevalence and antibiotics resistance pattern of class A bla CTX-M-1 and bla TEM-1 beta lactamases in uropathogenic Escherichia coli isolates from Pakistan.

Background/aim: Extended spectrum beta lactamase (ESBL) production among E. coli is one of the principal mechanisms that augment resistance to antibiotics. In the current study the molecular detection of class A beta lactamases among uropathogenic Escherichia coli was evaluated.

Materials And Methods: A total of 355 urine samples were collected from a tertiary care hospital in Peshawar. The ESBL production among E. coli isolates was detected by using the disc synergy diffusion method. Moreover, the molecular detection of bla TEM-1 and bla CTX-M-1 ESBLs, the antibiotic resistance pattern, and the minimum inhibitory concentrations (MICs) were also documented.

Results: Among the 355 urine samples, 157 isolates were E. coli, and 23.56% of the isolates were ESBL E. coli. Among phenotypic ESBL producers, bla CTX-M-1 and bla TEM-1 were found in 59.45% and 40.54% of the isolates, respectively. A high resistance rate was observed against aztreonam (97.29%), while the lowest resistance was observed against imipenem (2.7%). The MICs of ESBLs E. coli for ceftriaxone, ciprofloxacin, and gentamicin was >512 µg/mL, 4 µg/mL to 128 µg/mL, and 1 µg/mL to 14 µg/mL respectively.

Conclusion: The present study showed that bla CTX-M-1 ESBL production is more prevalent in our clinical E. coli isolates. More often the ESBLs were resistant to commonly used antibiotics.