Predictive score for vesicoureteral reflux in children with a first febrile urinary tract infection.

Objective: To develop a simple score for predicting vesicoureteral reflux after a first febrile urinary tract infection in children.

Methods: A retrospective cohort study was conducted for a 12-year period (January 2008 to December 2019), including patients aged <72 months who underwent renal ultrasonography and voiding cystourethrography after a first febrile urinary tract infection. Patients with a history of antenatal hydronephrosis were excluded. The prediction model and score for vesicoureteral reflux were developed using multivariate logistic regression analysis.

Results: Out of 260 patients in total (median age 4 months, 172 boys), 41 (16%) had vesicoureteral reflux. The score was based on four independent risk factors, including age >6 months (odds ratio 2.71, 95% confidence interval 1.27-5.76), presence of sepsis (odds ratio 3.44, 95% confidence interval 1.31-9.04), white blood cell count ≥15 000/mm (odds ratio 1.83, 95% confidence interval 0.88-3.8) and abnormal renal ultrasonography results (odds ratio 2.08, 95% confidence interval 1-4.31). A lower probability of vesicoureteral reflux (positive likelihood ratio = 0.66; P = 0.001) was found in the low-risk group (scores 0-2), whereas a higher probability of vesicoureteral reflux (positive likelihood ratio = 2.54; P = 0.001) was found in the high-risk group (scores 3-5). The predictive ability of the model was 70%.

Conclusions: The scores developed based on the patient characteristics and renal ultrasonography are useful in predicting presence of vesicoureteral reflux after a first febrile urinary tract infection in children and could guide clinicians' decisions to perform additional imaging studies.