Cholestasis is stagnation of bile due to impairment of bile flow along its outflow tract leading to accumulation of bile components in the blood. The two major componenets of bile are bilirubin and bile acids. Retention of bilirubin (BILIRUBINOSTASIS) produces jaundice and presence of bilirubin pigment9n hepatocytes, bile canaliculi and bile ducts. Retention of bile acids produces pruritus and typical changes in the periportal region of the liver which goes under the name of CHOLATE STASIS
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BILIRUBINOSTASIS
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CHOLATE STASIS |
Is a term indicating peculiar changes in periportal hepatocytes and attributed to stagnation of bile acids (Popper H, Hepathology, 1:187, 1981). The changes consist of hydropic swelling of hepatocytes with clearing of their cytoplasm and concentration of the remaining cytoplasm in the perinuclear region where it may form Mallory bodies. The process is accompanied with accumulation of copper-binding protein in autophagic vacuoles which can be stained with orcein (Salaspuro et al, Scand.J. Gastroenter., 11:677-682, 1976) or with specific antibodies (Janssens et al, Liver 4:139-147, 1984) together with copper granules that can be visualized with rhodamine stain. The protein was identified as metallothionein (Janssens 1984, ibid.). The changes are attributed to the detergent effect of retained bile acids. It is observed in extrahepatic biliary obstruction and primary cholestasis such as PBC (primary biliary cirrhosis) and PSC (primary sclerosing cholangitis). |