Antimicrobial resistance patterns in uropathogenic Escherichia coli causing urinary tract infections: A three-year data analysis

Urinary tract infections (UTIs) are among the most common bacterial infections worldwide and are predominantly caused by uropathogenic Escherichia coli (UPEC). The escalating burden of antimicrobial resistance (AMR) in UPEC increasingly undermines empirical treatment, particularly in India. This retrospective cross-sectional study evaluated 6,390 UPEC isolates obtained from urine samples of clinically suspected UTI patients between January 2022 and December 2024 at a tertiary diagnostic center in Eastern India. Bacterial identification and antimicrobial susceptibility testing were conducted using the VITEK-2 Compact automated system, and results were analyzed in accordance with Clinical and Laboratory Standards Institute (CLSI) guidelines. High resistance rates were observed against fluoroquinolones, including ciprofloxacin (~65.75%) and norfloxacin (~60.51%), and third-generation cephalosporin (~54-58%), suggesting the prevalence of extended-spectrum β-lactamase-producing strains. Moderate resistance was observed for trimethoprim-sulfamethoxazole (36.83%). However, carbapenem (≤8%), amikacin (5.44%), fosfomycin (2.97%), nitrofurantoin (13.12%), and cefoperazone/sulbactam (8.83%) demonstrated comparatively lower resistance rates, indicating antimicrobial efficacy against UPEC isolates. Year-wise analysis demonstrated a gradual increase in multidrug-resistant isolates over the three-year period. These findings indicate limited efficacy of commonly used oral agents and emphasize the urgent need for culture-based therapy, antimicrobial stewardship, and continuous regional AMR surveillance to prevent further escalation of multidrug-resistant UPEC in India.