Antimicrobial Susceptibility and Resistance Pattern of Escherichia Coli Isolated from Urine of Urinary Tract Infections (UTI) Patients

Abstract

Background: Urinary Tract Infection (UTI) remains one of the most frequently diagnosed bacterial infections worldwide, and Escherichia coli is the most common pathogen. Rising antimicrobial resistance (AMR) in UTIs is a major health threat, especially in low and middle-income countries like Pakistan, where antibiotic misuse is common. To evaluate the antimicrobial susceptibility and resistance pattern of E.coli isolated from urine samples of UTI patients and to identify clinical predictors of multidrug resistance (MDR).

Study Design: Cross-sectional study

Study Setting and Duration: Quaid-i-Azam University, Islamabad, from June 2023 to December 2023

Methodology: This analysis included 120 culture-positive urine samples. Demographic and clinical factors and microbiological details were recorded. Antimicrobial resistance patterns were compared according to age groups and clinical risk factors. Binary logistic regression was applied to identify independent predictors of MDR.

Results: The majority of participants were females (81.7%) and aged between 18–40 years (45.8%). High resistance was observed against commonly used antibiotics including Ciprofloxacin, Amoxicillin-Clavulanate and third-generation Cephalosporins. Carbapenem resistance was relatively lower but still present. Elderly age group demonstrated significantly higher resistance for certain antibiotics (p<0.05). Significant factors associated with MDR included prior antibiotic exposure, recurrent UTI and recent hospital admission (p<0.05). Regression analysis showed ESBL production (aOR=4.80), previous antibiotic use (aOR=3.25), recurrent UTI (aOR=2.90), hospital admission (aOR=2.48) and catheter use (aOR=2.70) as strong independent predictors of MDR.

Conclusion: E.coli causing UTI in this sample showed high antimicrobial resistance, with multiple clinical factors significantly contributing to MDR. Strengthening antimicrobial stewardship, avoiding unnecessary antibiotic prescriptions, improving infection control practices and continuous ESBL surveillance are urgently recommended to prevent further escalation of MDR burden in Pakistan.