Primary biliary cirrhosis.

Abstract

Primary biliary cirrhosis (PBC), an autoimmune, chronic, cholestatic liver disease that affects primarily women, is caused by the destruction of small bile ducts within the liver. A positive antimitochondrial antibody test is a sensitive and specific marker of this disease. PBC appears to be triggered by many different environmental factors in genetically susceptible hosts. Activated T lymphocytes recognize specific mitochondrial antigens, the dihydrolipomide acyltransferase component (E2) of pyruvate dehydrogenase and other oxoacid dehydrogenases, as foreign and attack bile duct epithelial cells that aberrantly express these antigens. If not treated, PBC progresses to cirrhosis and liver failure over a period of 10–15 years. The prognosis of PBC has improved greatly during the past decade because of its greater recognition by physicians, its diagnosis at early stages, and the good response of patients with early-stage disease to treatment with ursodeoxycholic acid. The disease is staged, from stages I to IV, based on liver biopsy findings. In stage I, disease is confined to portal triads. In stage II, inflammation and scarring have spread beyond portal triads. In stage III, adjacent portal triads are linked by bands of scarring and inflammation. In stage IV, there is nodule formation and unequivocal cirrhosis.