Urologic complications of ileal bypass operation for morbid obesity.

Preoperative, operative and postoperative data from a sampling group of 435 ileal bypass patients have been tabulated and computer-analyzed. Genitourinary disorders other than stone disease have been insignificant. Patients with stones and those without stones have been compared and the significant data tabulated. The incidence of stone disease is 6 per cent. All but 1 stone consisted of calcium oxalate. Oxalate levels were normal preoperatively and elevated in 60 per cent postoperatively. The stone formers are among the heaviest members of the studied population, they have the greatest amount of ileum bypassed and the greatest amount of 1 year weight loss. Correlations between these observations and possible pathways of metabolic stone disease are made.