Fig. 1.

Overview of diseases linked to disturbances in enterohepatic bile acid circulation. After their synthesis in hepatocytes, bile acids (BAs) are excreted into the bile and subsequently reabsorbed by enterocytes and, after completing the enterohepatic circulation, by hepatocytes. Efficient reuptake in the ileum preserves 95% of secreted BAs. Disturbances of transport processes within the enterohepatic circulation cause a variety of hepatic and intestinal disorders. Under normal conditions, BAs filtered by the kidney are conserved in the kidney (reabsorption in renal tubules) but can be alternatively excreted when BAs accumulate due to impaired biliary excretion in cholestasis. BAs, bile acids; BRIC, benign recurrent intrahepatic cholestasis; IBD, inflammatory bowel disease; ICP, intrahepatic cholestasis of pregnancy; NAFLD, non-alcoholic fatty liver disease; PBC, primary biliary cholestasis; PFIC; progressive familial intrahepatic cholestasis; PSC, primary sclerosing cholangitis.