Antibiotic Resistance Profiles of Escherichia coli Isolates from Urinary Tract Infections in Warri, Delta State

Escherichia coli is the most frequently implicated pathogen in urinary tract infections globally, and the emergence of resistant strains represents a growing therapeutic challenge in Nigerian healthcare settings. This study characterized antibiotic resistance profiles of E. coli isolates from UTI cases diagnosed at Central Hospital Warri and St. Joseph Hospital Warri, Delta State, in the South South geopolitical zone of Nigeria. Urine samples from 180 symptomatic patients were processed, and E. coli isolates confirmed by standard biochemical tests were subjected to antimicrobial susceptibility testing using the Kirby-Bauer disc diffusion method. A total of 95 E. coli isolates were recovered. Resistance rates were highest for ampicillin (82%), cotrimoxazole (74%), and nalidixic acid (68%). Sensitivity to nitrofurantoin remained high at 81 percent. ESBL production was confirmed in 38.9 percent of isolates using combined disc synergy testing. Multi-drug resistance was present in 61 percent of all isolates. Female patients between 20 and 40 years of age represented the highest proportion of UTI cases. These data support urgent revision of empirical UTI treatment protocols in Delta State, replacing ampicillin and cotrimoxazole with more reliable agents. Enhanced surveillance of ESBL E. coli in community settings is strongly recommended. Keywords: E. coli, urinary tract infection, antibiotic resistance, Warri, ESBL.