Emerging patterns of antimicrobial resistance in urinary tract infections: A three-year surveillance study from a tertiary care hospital in Nigeria

Abstract

Background: Urinary tract infections (UTIs) remain one of the most common bacterial infections worldwide, with increasing antimicrobial resistance posing significant therapeutic challenges. This study aimed to evaluate the antimicrobial resistance patterns of uropathogens and identify emerging trends in a Nigerian tertiary care setting. Methods: A retrospective analysis was conducted on 2,847 urine cultures from patients with UTIs between January 2022 and December 2024 at Prince Abubakar Audu University Teaching Hospital Anyigba, Kogi State. Bacterial identification was performed using conventional biochemical methods, and antimicrobial susceptibility testing was conducted using the Kirby-Bauer disk diffusion method according to Clinical and Laboratory Standards Institute guidelines. Results were statistically analysed using SPSS version 28.0, with significance set at p<0.05. Statistical significance was determined using chi-square and linear regression tests. Data were analyzed for resistance patterns, seasonal variations, and demographic associations. Results: Escherichia coli was the predominant pathogen (47.3%), followed by Klebsiella pneumoniae (18.2%) and Staphylococcus aureus (12.1%). Overall resistance rates were highest for ampicillin (78.4%), trimethoprim-sulfamethoxazole (71.2%), and ciprofloxacin (64.8%). Multidrug resistance was observed in 68.7% of isolates. Female patients aged 20-40 years showed the highest infection rates (34.2%), while elderly patients (>65 years) demonstrated significantly higher resistance rates (p<0.001). Seasonal analysis revealed peak resistance during the dry season months (November-March). Conclusions: The study reveals alarming levels of antimicrobial resistance among uropathogens, with multidrug resistance becoming increasingly prevalent. These findings emphasize the urgent need for antimicrobial stewardship programs and revised empirical treatment guidelines for UTI management in Nigeria.