Development of a prediction model for risk of breakthrough urinary tract infection in children with primary vesicoureteral reflux.

BACKGROUND

Many factors influence the risk of breakthrough urinary tract infection (BTUTI) in children with primary vesicoureteral reflux (VUR). Distal ureteral diameter ratio (UDR) and VUR index (VURx) have been shown in studies as predictors of BTUTI. We aimed to establish a predictive model through selecting voiding cystourethrography (VCUG)-related parameters in combination with clinical parameters for BTUTI in children with primary VUR.

METHODS

A retrospective cohort analysis was conducted on the clinical characteristics and VCUG-related parameters of patients with primary VUR. Univariable and multivariable analyses were performed to identify independent predictors and develop a model for predicting the probability of BTUTI. We compared our model against two other metrics for predicting BTUTI: the distal UDR and the VURx. The area under the receiver operating characteristic (ROC) curve (AUC), calibration curve, and decision curve analysis (DCA) were used to evaluate the predictive performance of the model.

RESULTS

A total of 193 patients were included in this study. Based on the results of univariable and multivariable analyses, three variables of sex (female) [odds ratio (OR): 3.39; 95% confidence interval (CI): 1.57-7.33], high-grade VUR (OR: 2.27; 95% CI: 0.98-5.25), and ureterovesical junction diameter of ureter (UVJ diameter) (OR: 5.85; 95% CI: 1.81-18.92) were used to create a prediction model and a nomogram. The AUCs for our model, the UDR, and the VURx in predicting the occurrence of BTUTI were 0.736, 0.680, and 0.546, respectively. The DCA revealed the clinical usefulness of the model.

CONCLUSIONS

This study identified three independent variables, namely, female sex, high-grade VUR, and UVJ diameter, for predicting the probability of BTUTI in primary VUR. The model and nomogram established in this study can greatly assist urologists in individualizing the management of primary VUR patients.