Biliary lipid composition in patients with nonoperated Crohn's disease.

Lipid composition of fasting duodenal bile was studied in 56 patients with nonoperated Crohn's disease, 21 normals matched for age and sex, 13 patients with cholesterol cholelithiasis, and 9 patients with ileal resections. Crohn's patients had a significantly higher mean saturation index, calculated according to Thomas (0.84 +/- 0.51) when compared to normal (0.63 +/- 0.25). Patients with ileocolonic Crohn's disease and patients with severe bile acid malabsorption, particularly, showed an increased incidence of cholesterol saturated bile. Saturation in patients with nonoperated Crohn's disease was not increased to the levels found in patients with ileal resection or cholesterol gallstones. Bile acid composition of gallbladder bile was characterized by a significant decrease of the deoxycholate fractions in patients with Crohn's ileocolitis and colitis as well as in ileal resected patients. These qualitative changes of bile acid composition may influence cholesterol solubility. It is concluded that patients with nonoperated Crohn's disease may have an increased risk of developing cholesterol gallstones.