The sigma rectum pouch (Mainz pouch II).

A low-pressure reservoir for urine is created by antimesenteric splitting and side-to-side anastomosis of the rectosigmoid, the expectation being to obtain better continence rates and better protection of the upper tract than are achievable by ureterosigmoidostomy. Between 1990 and August 1993 the procedure was performed in 73 patients (59 adults and 14 children) whose mean age was 43.5 years. The indications were malignancy (n = 55), bladder exstrophy/epispadias (n = 14), trauma (n = 3), and sinus urogenitalis (n = 1). Of the 73 patients, 69 were followed for a mean period of 127 (range, 1-34) months. In all, 5 early complications were encountered (6.8%). In addition, 8 late complications occurred (10.9%), stenosis at the ureteral implantation site being the most common one. Daytime continence was 94.5% and night-time continence, 98.6%. The sigma rectum pouch achieves excellent continence rates. Despite implantation of the ureters into a low-pressure reservoir, stenosis at the site of ureteral implantation occurred in 6.8% of the patients, demonstrating the profund vulnerability of ureterointestinal anastomosis.