Epidemiology and Antimicrobial Resistance of Uropathogens in a Tertiary Care Center in Riyadh, Saudi Arabia: A One-Year Retrospective Analysis

Urinary tract infections (UTIs) represent one of the most frequent bacterial infections worldwide, with <i>Escherichia coli</i> (<i>E. coli</i>) and <i>Klebsiella pneumoniae</i> (<i>K. pneumoniae</i>) as the predominant uropathogens. The emergence of extended-spectrum β-lactamase (ESBL)-producing Enterobacterales has severely limited treatment options, making regional surveillance crucial. This study aimed to determine the prevalence of uropathogens, assess antimicrobial resistance patterns, and evaluate the burden of ESBL-producing organisms among patients presenting with suspected UTIs in a tertiary care hospital in Riyadh. We conducted a retrospective analysis of 19,556 urine cultures from a tertiary care hospital in Riyadh, Saudi Arabia, between January and December 2024. Of these, 2629 (13.4%) cultures showed significant bacterial growth, predominantly in females (83.2%) and in the 16-30 year age group. <i>E. coli</i> accounted for 65.9% of isolates, followed by <i>K. pneumoniae</i> (16.8%). ESBL production was detected in 28.5% of <i>E. coli</i> and <i>Klebsiella</i> isolates. ESBL producers exhibited complete resistance to third-generation cephalosporins and β-lactam/β-lactamase inhibitor combinations, whereas carbapenems, aminoglycosides, and fosfomycin maintained high efficacy. Resistance to ciprofloxacin and co-trimoxazole was widespread in both ESBL and non-ESBL isolates. Additionally, vancomycin-resistant enterococci (7%), methicillin-resistant <i>Staphylococcus aureus</i> (2%), and carbapenem-resistant Enterobacterales (0.9%) were found. These findings highlight the escalating burden of ESBL-associated UTIs and underscore the urgent need for strengthened antimicrobial stewardship, continuous surveillance, and optimized empirical therapy to mitigate the impact of multidrug-resistant uropathogens in clinical practice.