Sclerosing cholangitis with thumbprint appearance and incomplete steroid response

Both primary sclerosing cholangitis (PSC) andimmunoglobulin G4 (IgG4)-related sclerosingcholangitis (IgG4-SC) are autoimmune-relatedinflammatory diseases that result in stricture or nar-rowing of the bile ducts. These diseases have beenconsidered independent entities based on the view-points of their etiologies, cholangiographic andpathological findings, their association with IgG4 andthe involvements of other organs.