Abstract
Objective: To identify the patterns of antimicrobial resistance in pathogens causing catheter-associated urinary tract infections (CAUTI).
Methodology: This cross-sectional study was carried out at Darul Sehat Hospital, Karachi, from January to June 2024. Urine samples from 179 catheterized patients were gathered aseptically and inoculated on Cysteine Lactose Electrolyte-Deficient (CLED) agar. The isolates were identified using biochemical testing and Gram staining. Demographic data, gender, and duration of hospital visits were recorded. The disc diffusion technique was used for antimicrobial resistance profiles. SPSS version 22 was used for data analysis.
Results: Among the study population, males dominated (55.9%) with a mean age of 53.5±19.46 years. Out of 179 urine samples, 34.07% were CAUTI-positive. The majority of the participants (65.9%) had comorbidities. Fever was reported in 74.3% of cases. Among culture-positive samples, Escherichia coli was the most prevalent (57.37%). The antimicrobial susceptibility showed high resistance to ampicillin (84%), followed by amoxycillin-clavulanic acid (66%), cefazolin, ciprofloxacin, and trimethoprim-sulfamethoxazole (62%), cefepime and cefotaxime (58%), and ceftriaxone (54%). In contrast, fosfomycin (6%), imipenem (14%), meropenem (16%), and nitrofurantoin (24%) were comparatively effective.
Conclusion: Multidrug-resistant (MDR) E. coli was identified as the predominant pathogen associated with CAUTI in this study. Fosfomycin, carbapenems, and nitrofurantoin exhibited good in vitro activity, suggesting their potential utility as an effective therapeutic option against MDR uropathogens.

Key words: Catheter-related infections, Escherichia coli, Klebsiella pneumonia, microbial sensitivity tests.