Prediction of moderate and high grade vesicoureteral reflux after a first febrile urinary tract infection in children: construction and internal validation of a clinical decision rule.

Purpose: Urinary tract infection leads to a diagnosis of moderate or high grade (III or higher) vesicoureteral reflux in approximately 15% of children. Predicting reflux grade III or higher would make it possible to restrict cystography to high risk cases. We aimed to derive a clinical decision rule to predict vesicoureteral reflux grade III or higher in children with a first febrile urinary tract infection.Materials and Methods: We conducted a secondary analysis of prospective series including all children with a first febrile urinary tract infection from the 8 European participating university hospitals.Results: A total of 494 patients (197 boys, reflux grade III or higher in 11%) were included. Procalcitonin and ureteral dilatation on ultrasound were significantly associated with reflux grade III or higher and then combined into a prediction model with an ROC AUC of 0.75 (95% CI 0.69–0.81). Given the prespecified constraint of achieving at least 85% sensitivity, our model led to the clinical decision r...