Primary biliary cirrhosis and autoimmune cholangitis

Primary biliary cirrhosis (PBC) is a chronic cholestatic liver disease of unknown etiology characterized by hightiter serum antimitochondrial autoantibodies (AMAs) and an autoimmune-mediated destruction of the small and mediumsized intrahepatic bile ducts. From a clinical standpoint, PBC is a peculiar, yet representative, autoimmune disease (Table). It affects women more frequently than men, with a female-to-male ratio of 9 to 1, and the average age at diagnosis is within the fifth and sixth decades of life, with exceptional cases described in pediatric ages. Epidemiological data indicate a geographical pattern of PBC prevalence and incidence rates, which are higher in northern countries (England, Scandinavia, northern United States). The diagnosis of PBC is made when two of three criteria are fulfilled, i.e., presence of serum AMAs, increased enzymes indicating cholestasis (i.e., alkaline phosphatase) for longer than 6 mo, and a compatible or diagnostic liver histology. Clinical symptoms include fatigue, pruritus, and jaundice. The progression of PBC varies widely for unknown reasons, as represented by certain patients remaining asymptomatic and others reaching liver failure at young ages.