Management of primary obstructive megaureter without reflux in neonates.

Systematic antenatal ultrasonography has significantly altered the conditions of diagnosis of megaureters. Pediatric urologists are now confronted with a large group of neonates with asymptomatic megaureter. Furthermore, reports of spontaneous resolution of primary megaureter without reflux have become common. We were confronted with 59 renal units in 48 neonates. We postulated that primary megaureter represented a significant obstructive uropathy when the kidney exhibited stasis and large pelvic and caliceal dilatations. So, 35 ureters were operated on initially. The other 24 cases were managed conservatively but among these patients, 11 ureters were operated on secondarily 7-29 months after the diagnosis because they were unchanged [6] or worsened [5]. 13 ureters are currently without treatment: 7 total regressions and 6 incomplete regressions with persistent mild pelvic dilatation. The results of reimplantation, early or delayed, have been excellent (1 postoperative necrosis reoperated, 1 secondary reimplantation, 2 persistent mild dilatations). Relief of obstruction without reflux was obtained in 36/39 long-term follow-up cases (92%). There is a disagreement about the relative merits of various modalities in the assessment of ureteral obstruction and impairment of renal function. Therefore, we chose to use essentially intravenous pyelography (IVP) and to operate initially when there was a delayed appearance of the contrast agent, a massive dilatation and delayed drainage from the ureter into the bladder. This attitude is open to question but no more illogical than waiting for impairment of renal function to decide on surgery.