PRIMARY, NON-REFLUXIVE MEGAURETER IN CHIL DHOOD

Diagnosis of megaureters in earlier years used to be made relatively l ate on the basis of clinical symptoms. Recently megaureters are being detected more frequently in asymptomatic children by perinatal ultraso und screening. Between 1986 and 1992 we observed 50 new patients with 57 primary, non-refluxive megaureters (pMU), 12 of whom were suspected by prenatal ultrasound. In the other cases, the mean age at diagnosis was 4 weeks, 22% of the patients showed clinical symptoms. A diuresis -renogram (99m-Tc-MAG3) was performed in 48 patients in order to diffe rentiate between non-obstructive dilatation and obstruction. In 21% of pMU a severe obstruction was detected. In 11/57 renal units (pMU) a t emporary urinary diversion (10 percutaneous nephrostomy, 1 end-uretero cutaneostomy) was the initial surgical treatment. The percutaneous nep hrostomies were kept in situ over a mean period of 3.3 (2-5) months. I n 4 of these the improved wash-out in the follow-up renogram permitted the removal of the percutaneous drain without further operation. In 1 2/57 pMU a ureteroneocystostomy was performed because of symptomatic u rinary tract infection or/and significant obstruction and poor ipsilat eral renal function. The postoperative renograms showed no significant obstruction. 43/57 pMU (75%) were initially observed conservatively. With 3 exceptions, no ureteroneocystostomy was performed within the fo llow-up period. Up to now, 40 (70%) pMU are only under conservative co ntrol without increasing dilatation of the renal pelvis and megaureter and/or deterioration of the wash-out or the renal function in the diu resis-renogramm. We believe that most neonatal primary, non-refluxive megaureters show an improvement of drainage in the long run allowing c onservative treatment.