Community Circulation of Multidrug-Resistant Escherichia coli Associated with Urinary Tract Infections

Background: This study aimed to investigate the antimicrobial resistance profile and the occurrence of multidrug resistance (MDR) among Escherichia coli isolates recovered from urine cultures of outpatients attending a public teaching hospital in Brazil and to assess the association of sex and age with MDR.Materials & Methods: This cross-sectional study was conducted based on a retrospective analysis of urine cultures collected from outpatients between January and December ۲۰۲۴. Descriptive statistics were applied, and univariate and multivariate logistic regression analyses were performed to identify factors associated with MDR.Findings: Among ۱۹۵۵ urine cultures analyzed, ۴۱۸ (۲۱.۴%) demonstrated significant bacterial growth, with E. coli accounting for ۴۸.۳% (n=۲۰۲) of the positive cultures. The highest resistance rates were to ampicillin (۵۶.۹%), ciprofloxacin (۳۷.۶%), and trimethoprim–sulfamethoxazole (۳۵.۰%), whereas the lowest resistance rates were observed to nitrofurantoin (۸.۳%) and fosfomycin (۳.۱%). MDR was identified in ۷۱ (۳۵.۱%) E. coli isolates, among which ۲۴ (۳۳.۸%) exhibited an extended-spectrum β-lactamase phenotype, and three (۴.۲%) produced carbapenemases. In the multivariate analysis, above-median age was independently associated with MDR (adjusted OR = ۲.۲۷; ۹۵% CI: ۱.۲۴–۴.۱۴)Conclusion: A substantial proportion of E. coli isolates from community-acquired urinary tract infections presented multidrug resistance, particularly among older patients. These findings emphasize the importance of local surveillance of antimicrobial resistance and periodic review of empirical treatment protocols in outpatient settings.

کلیدواژه ها:

Urinary tract infections ، Escherichia coli ، Microbial Drug Resistance ، Multiple Drug Resistance ، Drug Resistance Surveillance