Effect of dietary fiber on serum bile acids in patients with chronic cholestatic liver disease under ursodeoxycholic acid therapy

During ursodeoxycholic acid therapy for chronic cholestatic liver disease, the serum levels of lithocholic acid increase about twofold. Lithocholic acid has been shown to be hepatotoxic in some animal species. Administration of psyllium hydrophilic mucilloid (PHM), a dietary fiber, has been reported to increase the bile acid mass excreted by the feces. We, therefore, studied the effect of PHM (3 x 3.25 g/day) on serum bile acids including lithocholic acid in 12 patients with primary sclerosing cholangitis (n = 7) and primary biliary cirrhosis (n = 5) receiving ursodeoxycholic acid therapy. After 2 and 6 weeks of treatment with PHM, the serum levels of ursodeoxycholic acid increased by 52.4 +/- 72.8% (p <0.05) and 40.5 +/- 69.6% (NS), respectively. The absolute serum levels of lithocholic acid were not significantly changed. This led to a decrease of the relative amount of lithocholic acid as referred to total bile acids and to ursodeoxycholic acid in serum by 27.4 +/- 34.5% (p <0.05) and 25.5 +/- 32.8% (p <0.05), respectively, after 6 weeks of PHM treatment