Abstract:
Objective: The objective of the study is to compare the clinical profile, antimicrobial susceptibility pattern, severity indicators, and outcomes of
urinary tract infections (UTIs) caused by extended-spectrum beta-lactamase (ESBL)-producing and non-ESBL-producing Escherichia coli among
critically ill patients admitted to intensive care units (ICUs).
Methods: This retrospective observational study was conducted in a tertiary care teaching hospital over a three-year period and included 1237
culture-confirmed E. coli UTI isolates from ICU patients. Patients were categorized into ESBL and non-ESBL groups based on phenotypic ESBL
detection. Demographic variables, clinical presentation, comorbidities, complications, antimicrobial susceptibility, ICU stay, Acute Physiology and
Chronic Health Evaluation (APACHE IV) and Sequential Organ Failure Assessment (SOFA) scores, and clinical outcomes were analyzed.
Results: Among 1237 isolates, 742 (60.0%) were ESBL producers and 495 (40.0%) were non-ESBL producers. ESBL infections were associated with
higher complication rates, including renal failure (58.0%), septic shock (18.0%), and multi-organ dysfunction syndrome (10.0%). Mean ICU stay was
significantly longer in the ESBL group than in the non-ESBL group (5.1 vs. 3.6 days; p<0.01). Mortality was higher among ESBL patients than among
non-ESBL patients (12.4% vs. 6.8%), with an absolute risk difference of 5.5% (95% confidence interval: 2.3–8.8%). APACHE IV and SOFA scores
showed good mortality prediction, with area under the curve values of 0.82 and 0.79, respectively. Carbapenems showed the highest sensitivity among
ESBL isolates.
Conclusion: ESBL-producing E. coli UTIs in ICU patients are associated with increased morbidity, prolonged ICU stay, higher complication rates, and
greater mortality. Early identification, appropriate empirical therapy, severity-based risk stratification, and antimicrobial stewardship are essential
to improve clinical outcomes.
