Kock urinary reservoir maturation in children and adolescents: Consequences for kidney and upper urinary tract

Objective: To study Kock reservoir maturation in children and adolescents a nd its effects on the kidneys and upper urinary tract. Methods: Ten boys an d 10 girls, aged 10.8-18 years, had Kock reservoir surgery for congenital u rinary incontinence. They were followed for 3-10 years, divided into 3 diff erent periods, and assessed with urography and enterocystography, the findi ngs of which were correlated to renal function as measured by Cr-51 EDTA cl earance, reservoir endoscopy and patient's history. Results: The reservoir was located in the pelvis and remained in this position throughout the whol e followup in 75% of patients and in the lower or midabdomen in 25%. Angled efferent nipple seen on enterocystoscopy or enterocystography coincided wi th nipple dysfunction, reservoir malposition or infrequent reservoir emptyi ng. Upper urinary tract dilatation was detected in 84% of patients 3 months after surgery, 25% at 1 year and 30% at 2-10 years. The dilatation was imp roved in 56% of patients and unchanged in 25% after 1 year. The situation c ontinued to improve at late follow-up. New focal renal scars were radiologi cally detected in 1 of 19 at early and in another 1 of 17 patients at late follow-up. Progression of old scars was detected in 1 of 19 at early and in 4 of 17 at late follow-up. Eight of 19 cases had deterioration of renal fu nction with a change in the split renal function. Of these 8 patients, 7 re ported infrequent reservoir evacuation. Conclusions: Kock reservoir is a us eful form of urinary diversion in children and adolescents with congenital urinary incontinence. Radiological examinations are good methods of follow- up of the maturation of the pouch and its effects on the urinary tract and for detection of complications. Urinary tract dilatation is a frequent find ing early after surgery but it subsides in most cases 3-12 months after sur gery. Long-term efferent nipple dysfunction may be the result of angulation , reservoir stones, malposition and/or overdistension. Permanent renal dama ge may be due to pyelonephritis, stones, infrequent reservoir emptying or u rinary obstruction. A strict regime of reservoir evacuation to avoid overdi stension and nipple dysfunction and to decrease the possibility of renal fu nction deterioration is strongly advisable in these patients. It is imperat ive that their own management of the reservoir is continuously supervised.