Multidrug Resistance Patterns in Asymptomatic Bacteriuria among Patients with Comorbidities

Abstract

Background: Asymptomatic bacteriuria (ASB) is common among individuals with chronic comorbidities and may contribute to the growing burden of antimicrobial resistance. The emergence of multidrug-resistant (MDR) uropathogens poses significant challenges to clinical management, particularly in patients with repeated healthcare exposure and underlying medical conditions. This study aimed to investigate the prevalence and determinants of multidrug resistance in ASB among patients with comorbidities. Methods: A cross-sectional descriptive study was conducted in the nephrology outpatient department of Abbasi Shaheed Hospital, Karachi, between December 2024 and May 2025. A total of 208 adults aged 21–60 years with asymptomatic bacteriuria and at least one comorbidity was recruited through convenience sampling. Demographic and clinical data were collected using a structured questionnaire, while urine cultures and antibiotic susceptibility testing were performed using standard microbiological techniques. Descriptive statistics, chi-square tests and logistic regression analysis were applied to identify factors associated with MDR. Results: Bacterial growth was detected in 53.8% of participants, while 46.2% showed no growth. Multidrug-resistant organisms were identified in 19.7% of the study population. Escherichia coli was the predominant uropathogen, followed by Klebsiella, Enterococcus, Pseudomonas and Staphylococcus saprophyticus. Diabetes mellitus and immunosuppression demonstrated borderline associations with MDR, whereas chronic kidney disease showed a near-significant relationship. Catheterization emerged as the only independent predictor of multidrug resistance. Carbapenems, particularly meropenem and imipenem, exhibited the highest susceptibility rates, whereas resistance to amoxicillin and ciprofloxacin was comparatively high. Conclusion: Asymptomatic bacteriuria among patients with comorbidities represent an important reservoir of multidrug-resistant pathogens. Continuous surveillance, culture-guided treatment, rational antibiotic prescribing and improved catheter-management practices are essential to limit the spread of antimicrobial resistance and improve patient outcomes.

Keywords: asymptomatic bacteriuria, multidrug resistance, antimicrobial resistance, comorbidities, catheterization, uropathogens, antibiotic susceptibility.