Procalcitonin as a predictor of vesicoureteral reflux in children with a first febrile urinary tract infection

Objective. A first febrile urinary tract infection leads to the diagnosis of vesicoureteral reflux in 20% to 40% of children. Systematic voiding cystourethrography then is recommended. However, for 60% to 80% of the children, voiding cystourethrography is a posteriori normal. Moreover, it is irradiating, painful, and expensive. Thus, selective approaches are needed. Because procalcitonin has been shown to be associated with severe pyelonephritis and renal scars, which are correlated to vesicoureteral reflux, we analyzed its relationship with vesicoureteral reflux. Methods. A retrospective hospital-based cohort study included all children who were 1 month to 4 years of age and had a first febrile urinary tract infection. Univariate and multivariate analyses were performed. Results. Among 136 patients included, 25% had vesicoureteral reflux. The median procalcitonin concentration was significantly higher in children with reflux than in those without (1.2 vs 0.6 ng/mL). High procalcitonin (>= 0.5 ng/mL) was associated with reflux (odds ratio [OR]: 4.6; 95% confidence interval [CI]: 1.6-16.2). After logistic-regression adjustment for all potential confounders, the association remained significant (OR: 4.9; 95% CI: 1.7-14.0). The relationship was stronger for high-grade (>= 3) reflux (OR: 8.7; 95% CI: 1.2-382) than low-grade reflux (OR: 3.6; 95% CI: 1.1-15.3). High procalcitonin sensitivities were 85% (95% CI: 70-94) and 92% (95% CI: 65-99) for all-grade and high-grade reflux, respectively, with 44% specificity (95% CI: 35-54). Conclusion. High procalcitonin is a strong and independent predictor of vesicoureteral reflux and could be used to identify low-risk patients to avoid unnecessary voiding cystourethrography.