Antenatal and perinatal uro-nephrology: current questions and dilemmas.

The development of antenatal ultrasonography and the detection of fetal uropathies has created a new field for paediatric urologists. The embryology and physiology of the fetal renal tract is still poorly understood. It is, however, recognised that delays in the maturation of the renal system can lead to transient dilatation of the urinary tract. Structural and functional anomalies can also result in dilatation, but these are permanent. The ability to distinguish between the transient and permanent impairments to urine flow represents a diagnostic challenge. This review article discusses the pathophysiology of urine flow impairment, antenatal detection and the postnatal management of the common congenital uropathies.