Definition

 • A chronic liver disease characterized by the destruction of small intrahepatic bile ducts and the presence of anti- mitochondrial antibodies.

 Terminology

 • Previously called primary biliary cirrhosis.

 • the name has changed because less than half of patients with this condition have cirrhosis.

• there are cases which have serological features of an autoimmune hepatitis, but pathological features of primary biliary cholangitis (PBC) and these cases are best termed autoimmune cholangitis unless the biopsy shows a severity of inflammation beyond that seen in PBC in which case it is an ‘overlap syndrome’.

 Epidemiology

 • uncommon.

 • Occurs most frequently in middle- aged women and is associated with other autoimmune conditions.

 Aetiology

 • unknown, but may be triggered by infection with organisms that show molecular mimicry to antigens on the biliary epithelium.

Pathogenesis

 • thought to be an autoimmune disease in which the immune system mounts an abnormal response to the biliary epithelium.

 Presentation

• Asymptomatic in its early stages, although may be picked up by elevated alkaline phosphatase levels. It should be noted that a rise in bilirubin is a late feature.

 • Patients presenting with symptoms usually do so with fatigue or pruritus due to the accumulation of bile salts.

 Serology

• >95% of cases are associated with the presence of anti- mitochondrial antibodies directed at a component of the pyruvate dehydrogenase enzyme complex located in the inner mitochondrial matrix.

Macroscopy

 • early disease shows few macroscopic changes in the liver.

• In advanced disease, the liver is cirrhotic and bile- stained.

 Histopathology

• earliest feature is the infiltration and destruction of interlobular bile ducts by lymphocytes and macrophages (‘florid duct lesion’). the macrophages may coalesce into clusters and form granulomas.

• Copper accumulates in the liver as it cannot be excreted via the biliary tree.

• As the disease progresses, there is inflammation and destruction of hepatocytes at the edges of the portal tracts (interface hepatitis) which begins a sequence of periportal fibrosis l portal– portal bridging l cirrhosis.

Prognosis

 • Gradual progression towards cirrhosis over 15– 20 y. • ursodeoxycholic acid therapy decreases the rate of progression.