Abstract / Summary
Background: Urinary tract infections remain among the most common infections globally, with Escherichia coli (E. coli) as the predominant causative pathogen. The increasing antimicrobial resistance (AMR) among E. coli isolates poses significant clinical and public health challenges. This study aimed to evaluate the quarterly distribution and resistance patterns of E. coli isolates from urine samples over a 3-year period in a tertiary care hospital. Materials and Methods: A total of 29,816 urine samples were processed from January 2022 to December 2024. Culture-positive isolates for E. coli were analyzed quarterly for trends in prevalence and AMR. Resistance data were stratified by major antibiotic classes, and multidrug resistance (MDR), extensively drug-resistant (XDR), and pan-drug-resistant (PDR) patterns were identified. MIC 50 and MIC 90 values were calculated for key antimicrobials. Results: Of the total processed samples, 8385 were positive for E. coli , showing a slight decline over the 3 years. The overall prevalence of E. coli was 28.12%. The highest resistance was observed to ampicillin (78%), ciprofloxacin (64%), and trimethoprim–sulfamethoxazole (59%), while fosfomycin (8%) and nitrofurantoin (12%) remained the most effective oral agents. Quarterly analysis revealed fluctuations in MDR, XDR, and PDR rates across all major antibiotic classes, with aminoglycosides and carbapenems showing high rates of resistance. MIC 50 and MIC 90 values supported resistance findings and indicated a shift towards reduced susceptibility over time. Conclusion: This study highlights the alarming rise of AMR in uropathogenic E. coli , emphasizing the need for continuous surveillance, rational antibiotic use, and the development of new therapeutic strategies. The quarterly tracking of resistance trends provides valuable insights into local AMR epidemiology and can guide empirical therapy and stewardship interventions.