Value of Bladder Debris on Renal-Bladder Ultrasound for Predicting Urinary Tract Infection in Children

Abstract

Background: Bladder debris is a common finding on renal-bladder ultrasonography; however, its significance as an indicator of a urinary tract infection (UTI) remains uncertain. Objectives: This study aimed to determine the predictive value of bladder debris in children evaluated for a suspected UTI. Methods: We analyzed data from 381 symptomatic children admitted between 2023 and 2024 with unspecified fever, abdominal pain, gastroenteritis, or urinary symptoms. All patients underwent renal-bladder ultrasonography, urinalysis, and urine culture. Results: Patients were classified according to the presence or absence of UTI and bladder debris on ultrasound. Among the 381 children, 192 had positive urine cultures. Escherichia coli was the most frequently isolated organism, accounting for 70% of culture-positive cases. Binary logistic regression showed no significant association between bladder debris and UTI in the univariate analysis (OR = 1.121; 95% CI, 0.750 - 1.676; P = 0.576). After adjustment for age and sex, bladder debris was significantly associated with UTI (OR = 1.937; 95% CI, 1.123 - 3.339; P = 0.017). However, receiver operating characteristic (ROC) curve analysis showed poor diagnostic discrimination, with 53.13% sensitivity, 49.74% specificity, and an area under the curve of 0.514 (P = 0.577). Conclusions: Although bladder debris was significantly associated with UTI after adjustment for age and sex, it demonstrated poor diagnostic accuracy and limited predictive value. Therefore, bladder debris should not be used as the sole indication for obtaining a urine culture in symptomatic children evaluated for suspected UTI.