Anti-Mitochondrial Antibody

Anti-mitochondrial antibodies (AMA) are highly associated with Primary Biliary Cholangitis (PBC), a chronic autoimmune cholestatic liver disease characterized by progressive inflammatory destruction of the small intrahepatic bile ducts that may ultimately lead to cirrhosis. PBC occurs predominantly in females between 20 and 60 years of age, although rare pediatric cases have been reported. Indirect immunofluorescence (IIF) in rodent tissue typically serves as a screening method for AMA. AMA detected by IIF demonstrates high diagnostic performance for PBC, with specificity generally exceeding 90–95%. Approximately 90–95% of patients with PBC are AMA positive, particularly against the M2 antigen complex. Because low-titre AMA may occasionally occur in other autoimmune, infectious, or hepatic conditions, confirmation with antigen-specific immunoassays (e.g., AMA-M2 ELISA or line immunoassay) is recommended for samples with positive IIF results or when clinical suspicion for PBC remains high despite negative AMA by IIF.