[Neonatal asymptomatic and childhood symptomatic hydronephrosis: Are they different nosological entities?].

The authors reviewed two groups of patients with ureteropelvic junction obstructión divided by age and mode of presentation: patients with neonatal asymptomatic hydronephrosis diagnosed by prenatal ultrasonography and patients with symptomatic hydronephrosis. It was assumed that in these patients we are observing a continuous spectrum of the same pathology; nevertheless, some relevant differences were found between the two groups. Diuretic renograms did not show any change in postoperative renal function among prenatally detected cases while a significative improvement followed surgery among most of symptomatic cases. A possible explanation could be found in the obstructive mechanism which was responsible of obstruction in a significative proportion of these patients. Lower polar vessels produce a progressive symptomatic hydronephrosis in an healthy kidney in respect to intrinsic obstruction which are mainly found among prenatally detected cases and which are frequently associated to congenital renal damage unresponsive to surgery.