URINARY-DIVERSION IN CHILDREN AND YOUNG-ADULTS USING THE MAINZ-POUCH-I TECHNIQUE

Objectives To determine the late complications and consequences for re nal function, vitamin and acid-base metabolism after application of th e Mainz Pouch I (MZP-I) technique in children and young adults. Patien ts and methods To November 1994, the MZP-I procedure was carried out i n 463 patients at our institution, 91 of whom were children and adoles cents (less than or equal to 20 years old) using bladder augmentation in 21 and a continent cutaneous stoma in 70. A minimum follow-up of 1 year was possible in 87 patients or 163 renal units (RUs) with a mean of 5.5 years (range 1-10.5). Results At the last examination, 23 of 55 (42%) preoperatively dilated RUs had improved, 131 of the 163 RUs (80 %) were stable and nine RUs (5.5%) showed a slight clinical asymptomat ic increase in the upper tract dilatation. Through an extraperitoneal flank incision, 11% of the RUs which developed stenosis at the uretero colic anastomosis were successfully reimplanted (16% in patients with neurogenic disorders, 17% with pre-operative irradiation and 5% in the remaining patients), Two of 32 patients with an intussuscepted and in vaginated ileal nipple required re-operation due to incontinence, but none of the patients with an appendiceal stoma were incontinent. Open revision of a stomal stenosis was performed in three and endoscopic tr eatment in nine patients. In 54 patients, the levels of vitamins A, B- 1, B-2, B-6, E, folic and bile acid were within normal ranges. There w as no significant decrease in vitamin B,, levels after operation, In n one of the patients with normal pre-operative creatinine values had th e levels increased and none developed severe acidosis or bowel neoplas m. Conclusion The MZP-I is recommended as a technique for bladder augm entation or continent urinary diversion in children and young adults, with an acceptable complication rate which offers long-term protection of the upper urinary tract.