Effect of colectomy on bile composition, cholesterol crystal formation, and gallstones in patients with ulcerative colitis.

Bile composition and the presence of cholesterol crystals in bile were studied in bile samples obtained at the time of surgery in patients with ulcerative colitis. Some patients were sampled before colectomy and others at a second operation months to years after a colectomy. Patients in the precolectomy group were found to have bile composition similar to control patients without gallstones, and few had crystals in their bile. In the postcolectomy group, cholesterol concentrations were very high, all biles were supersaturated, and almost all patients had cholesterol crystals in their bile. These findings are similar to those found in persons with cholesterol gallstones. Twenty patients have been followed for at least 3 years after colectomy and to date three have formed cholesterol gallstones.