Pathogenesis of human cholesterol cholelithiasis

The pathogenesis of cholesterol cholelithiasis in humans was studied by means of 3 techniques. The cholesterol solubilizing capacity of the bile may be determined by estimation of the relative composition of the 3 major lipid constituents of bile. Consistent reduction in the cholesterol carrying capacity of gallbladder bile of persons with gallstones, when compared with normal subjects, was not shown. Normal subjects frequently have supersaturated bile. Secretion rates of biliary lipids were estimated by 2 methods; with the method that appears to be more physiologic, no change in lipid secretion rates was found in gallstone patients. Bile acid pool size was measured by isotope dilution techniques; it is reduced in patients with gallstones. It is not clear whether this reduction is important in the pathogenesis of cholesterol cholelithiasis, for the bile acid secretion rate is normal because of an increased rate of cycling of the pool through the enterohepatic circulation. The role of the gallbladder in the genesis of cholesterol cholelithiasis may be more important than has been realized.