Long-term metabolic and nutritional effects of urinary diversion

To evaluate the long-term metabolic and nutritional consequences of interposing intestinal segments in the urinary tract.

Comprehensive analyses of blood and urine were performed in 20 patients with conduit urinary diversion and in 19 with continent cecal reservoir for urine, all with normal or near-normal renal function. The mean follow-up time was 15 years in the conduit group and 9 years in the reservoir group.

In both patient groups, arterial blood gas analysis revealed a tendency to metabolic acidosis with respiratory compensation. Although no hyperchloremia was found in either group, the mean value of serum chloride was significantly higher (P < 0.05) in the reservoir group than in the conduit group. The calciotropic factors, plasma lipids, lipoproteins, and liver function values were normal in both groups. Serum vitamin B12 levels were subnormal in 3 conduit and 2 reservoir patients, but other studied variables of intestinal absorption were within normal limits. Conduits utilizing colonic segments showed calcium excretion on the same level as in reservoirs, which was significantly higher than in conduits made from ileal segments.

Except for increased risk of vitamin B12 deficiency, no major adverse metabolic or nutritional effects of conduit or continent urinary diversion were found at long-term observation in patients with well-preserved renal function. Lifelong surveillance of vitamin B12 levels is necessary in these patients.