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What is "Onion-skin" fibrosis of bile duct is seen in and explain in detail?
Pathology of Primary sclerosing cholangitis Cholangiocytea, epithelial cells that lines the bile duct are target cell of injury in PSC Histologic finding "Onion skin appearance" is pathognomic of PSC, but seen in <10% cases Involvement of large intrahepatic and extrahepatic duct distinguishes PSC from PBC Absence of the smallest intrahepatic ducts leading to a reduction in the branching of biliary tree (giving rise to pruned-tree appearance on direct cholangiography) Histologic changes in the same liver can be markedly varied from segment to segment at any given time Ref: Sabiston 20th edition Pgno :1508-1509