Stenosis of the afferent antireflux valve in the Kock pouch continent urinary diversion: diagnosis and management.

Between August 1982 and May 1988, 503 patients underwent construction of a continent ileal reservoir (Kock pouch) for cutaneous urinary diversion at our university. Stenosis of the afferent antireflux valve resulted in upper urinary tract obstruction in 11 patients (2%). In addition, 2 patients underwent Kock pouch diversion elsewhere and upon referral to our institution they had afferent valve stenosis. To date 13 patients have been identified with this problem. Hydronephrosis was present in 100% of the functional kidneys in these patients. Radiographs of the Kock pouch were uniformly normal without evidence of reflux or other pathological condition. The most common presenting symptom was flank pain in 7 patients (54%) and the most common presenting sign was creatinine elevation above baseline in 7 (54%). Infections recurred with or without sepsis in 5 patients (38%). Ureteroileal anastomotic strictures were not present in any patient. The interval from creation of the Kock pouch to the diagnosis of stenosis ranged from 2 to 75 months (mean 39). All patients underwent endoscopic evaluation of the Kock pouch confirming stenosis of the afferent antireflux valve, and subsequent mechanical dilation of the stenotic valve. Dilation procedures were repeated in 6 patients (46%), 4 of whom subsequently required open surgical revision of the afferent valve. Of these patients 3 are clinically stable and 1 died of the primary malignancy. The remaining 2 patients are clinically and radiographically stable after multiple dilations. Of the 7 patients (54%) requiring only a single dilation 6 are clinically stable and 1 died of the primary malignancy. Stenosis of the afferent antireflux valve of the Kock pouch, previously unreported to our knowledge, is a rare late complication leading to flank pain, hydronephrosis, recurrent infection and elevation of serum creatinine levels. Approximately 50% of the patients respond to a single dilation of the nipple valve. However, most patients who require repeat dilation will need open surgical revision.