Pelviureteric obstruction in neonates and sucklings

Sonography is the initial diagnostic procedure and has to be repeated after birth. The consecutive voiding cysturethogram is of paramount importance and can rule out a simultaneous reflux or even a reflux-induced hydronephrosis. In an isolated stenosis of the ureteropelvic junction infusion excretory urography does not reveal additional information. Furosemideradionuclide renography is standardized and well-known diagnostic method however its evaluation and the conclusion derived from it in newborns with immature renal function is yet unclear. The use of Duplex-doppler sonography for evaluation of obstruction of the upper urinary tract is in clinical development but is technically difficult in the newborn. (orig./MG)