Antibiogram of Extended Spectrum Beta-Lactamase (ESBL) Producing Uropathogens at Tertiary Care Hospital: A Descriptive Cross Sectional Study

Abstract

Urinary tract infection (UTI) is one of the most common bacterial infections worldwide. The emergence of extended-spectrum β-lactamase (ESBL) producing uropathogens has become a major therapeutic concern due to their multidrug-resistant (MDR) nature and limited treatment options. This study aimed to determine the prevalence of ESBL-producing uropathogens and their antimicrobial susceptibility pattern in a tertiary care hospital. A descriptive cross-sectional study was conducted at the Clinical Microbiology Laboratory of Nepal Medical College Teaching Hospital, Kathmandu, Nepal, from January 2026 to June 2026. A total of 3,132 urine samples from patients with suspected UTIs were processed using standard microbiological methods. Antimicrobial susceptibility testing and ESBL detection were performed according to CLSI 2025 guidelines. Significant bacteriuria was detected in 396 (12.64%) samples, of which 385 (97.22%) were Gram-negative isolates. Escherichia coli was the predominant pathogen (80.05%), followed by Klebsiella spp. (12.63%). ESBL production was confirmed in 40 (10.40%) isolates, of which 36 (90.00%) were E. coli. ESBL-producing isolates were more common in females (62.50%) and in patients aged 41–60 years (40.00%). The highest number of isolates were susceptible to imipenem and meropenem (92.50%), followed by amikacin (77.00%), nitrofurantoin (70.00%), and piperacillin/tazobactam (70.00%). All ESBL-producing isolates were MDR. ESBL-producing E. coli remains an important cause of UTIs and exhibits universal MDR, limiting therapeutic options. Carbapenems a last resort drug remain the most effective treatment, while amikacin and nitrofurantoin retain good activity. Therefore, routine ESBL surveillance and antimicrobial stewardship are essential to limit the spread of antimicrobial resistance and guide empirical therapy.