FREQUENCY OF DIFFERENT BACTERIA CAUSING URINARY TRACT INFECTION IN PATIENTS AT UNIVERSITY OF LAHORE TEACHING HOSPITAL, LAHORE

Abstract

ABSTRACT

Background

Objective: To determine the frequency of different bacteria causing urinary tract infection in patients at University of Lahore Teaching Hospital, Lahore.

Methods: This descriptive cross-sectional study was conducted in the Department of Medicine, University of Lahore Teaching Hospital, Lahore, from November 2025 to April 2026. A total of 168 patients with urinary tract infection were enrolled through non-probability consecutive sampling. Patients aged 20–80 years with pyuria (≥5 pus cells/high-power field) and positive urine culture were included. Patients with recent antibiotic use, fungal growth, pregnancy, menstruation, or refusal of consent were excluded. Urine samples were cultured on CLED medium, and bacterial isolates were identified using colony morphology and Gram staining, followed by antimicrobial susceptibility testing. Data was analyzed using SPSS version 26, and a p-value ≤0.05 was considered statistically significant.

Result: A total of 168 patients were included in the study, with a mean age of 55.78 ± 22.97 years, there were 84 (50%) male and 84 (50%) females enrolled. Escherichia coli was the most frequently isolated organism (28 n=47), followed by Enterococcus species and  Pseudomonas aeruginosa (20.2%, n=34) respectively. The antimicrobial susceptibility pattern demonstrated high resistance to commonly used antibiotics, particularly ciprofloxacin (88.7%, n=149), norfloxacin (68.5%, n=115), fosfomycin (67.9%, n=114), gentamicin (64.3%, n=108), nitrofurantoin (53.6%, n=90), piperacillin–tazobactam (53.0%, n=89), cefuroxime (51.2%, n=86), ceftriaxone (47.6%, n=80), amikacin (47.0%, n=79), and trimethoprim–sulfamethoxazole (40.5%, n=68). Among the tested antibiotics, colistin demonstrated the highest susceptibility (73.2%, n=123), followed by meropenem (56.0%, n=94), whereas imipenem showed a comparatively lower susceptibility rate (20.2%, n=34).

Conclusion: The present study concluded that Escherichia coli remains the most common causative organism of urinary tract infections, followed by Enterococcus species and Pseudomonas aeruginosa, indicating a diverse spectrum of both Gram-negative and Gram-positive pathogens in the study population.

Keywords: E. Coli, Urinary Tract Infection, Gram-negative bacteria