Vesicoureteral Reflux in Neonates with Hydronephrosis; Role of Imaging Tools

Abstract

Objective: Neonatal Hydronephrosis is a common abnormality diagnosed ante‐ or postnatally. The aim of this study was to determine the prevalence and severity of vesicoureteral reflux (VUR) in neonates with antenatal or postnatal hydronephrosis and the value of ultrasono‐ graphy as a noninvasive tool for VUR prediction. Methods: In a prospective study, 202 infants with neonatal hydronephrosis were studied. Two successive renal ultrasound examinations were performed at 1 and 4‐6 weeks after birth in neonates with antenatal hydronephrosis or immediately after presentation. Voiding cysto‐ urethrography (VCUG) was performed in all infants. Findings: The incidence of VUR was 29.7%, of which 17.8% had severe (grade IV‐V) reflux. 27% of 133 neonates with unilateral and 34.8% of 69 cases with bilateral hydronephrosis had VUR. Although a significant association was observed between severity of hydronephrosis and VUR, 5.9% of normal appearing and 7.8% of grade 1 hydronephrotic neonates had high‐grade reflux. Conclusion: VUR was observed significantly in hydronephrotic neonates. A normal or mildly hydronephrotic urinary tract on ultrasound scan cannot exclude presence of severe VUR. We recommend performing VCUG in all hydronephrotic newborns.