Purpose: The natural history of and optimal treatment for asymptomatic congenital hydronephrosis is unknown, mainly because most published series are nonrandomized or retrospective with nonstandardized followup regimens. In this survey we provide an overview of the different strategies used for the treatment of congenital unilateral hydronephrosis.
Materials and methods: A comprehensive literature review of clinical studies of asymptomatic congenital unilateral hydronephrosis is presented.
Results: Different criteria for surgical intervention and different followup regimens have been used. Identification of the population at risk has been attempted but results are ambiguous. Surgery is done in approximately 25% of cases when using deteriorating differential function, symptoms and/or increasing hydronephrosis as criteria for operation. A nonstandardized renographic assessment does not compromise evaluation of the ideal followup but it may compromise the functional outcome.
Conclusions: More studies of kidneys with decreased function, severe hydronephrosis or poor drainage investigated with a standardized protocol are needed to clarify the natural history and establish optimal guidelines for treatment and followup.