Primary sclerosing cholangitis (PSC) is a chronic fibro-obliterative inflammation of intra-and/or extrahe-patic bile ducts of unknown origin. Small duct primary sclerosing cholangitis (formerly called pericholangi-tis) is an intrahepatic variant of PSC in patients with chronic cholestasis and hepatic histology compatible with PSC, but normal findings on endoscopic retrograde or magnetic resonance cholangiography.