[Primary megaureter detected during the first year of life. Review of case reports in the last 10 years and analysis of prognostic factors].

AIM We report our experience in the treatment of primary megaureter discovered prenatally or in the first year of life. We also discuss the prognostic role of the first diuretic renogram performed immediately after the discovery of the megaureter. MATERIAL AND METHODS 45 patients have been observed since January 1990 until December 1999, with 54 primary non refluxing megaureters (9 bilateral cases); 18 discovered prenatally; 24 detected during a postnatal echographic screening of urinary malformations; and 3 symptomatic. All the patients have been studied and followed-up with repeated sonograms and diuretic nephrograhis. RESULTS 19 patients underwent surgery, 5 at presentation and 14 early during follow up. In this group, 7 patients were operated on because of urinary tract infection, 5 had a functional impairment of the involved kidney and 2 presented a progressive increase of ureteral size. 29 megaureters have been followed non operatively, of these, 6 resolved and 19 improved dilatation, 10 were unchanged and 3 cases underwent progressive worsening. Half time clearance (T 1/2) calculated during the first diuretic renogram had a favorable prognostic significance when the value was under 10', but when the value was above 10' the evolution was unpredictable.