Congenital Hydronephrosis

Abstract

Congenital hydronephrosis is the most common anomaly diagnosed by routine prenatal ultrasound. Though in the majority of cases the hydronephrosis is not clinically significant, there are a number of patients who would suffer if hydronephrosis were left untreated. Since congenital hydronephrosis is largely asymptomatic, management is a clinical challenge with a wide gray zone. In the majority of cases, a postnatal ultrasound is the initial step in the workup of congenital hydronephrosis. The Society for Fetal Urology (SFU) has recently updated their grading system for ultrasound evaluation of hydronephrosis, and this provides both a good basis for standardization of studies and reporting and a risk assessment model. Additional studies including voiding cystourethrogram and diuretic renography are used selectively based on the severity of hydronephrosis and suspected underlying pathology. Identifying the select group of patients who will benefit from early intervention to prevent renal damage as a consequence of hydronephrosis generally requires follow-up over time. Deterioration in hydronephrosis, parenchymal thickness, and renal function are the main indications for treatment.