Antimitochondrial antibody

Antimitochondrial antibody (AMA) is a type of autoantibody that targets mitochondria, the energy-producing structures within cells. AMAs are most commonly associated with primary biliary cholangitis (PBC), a chronic liver disease.

Overview

Antibodies are proteins produced by the immune system to fight off foreign substances like bacteria and viruses. However, in some cases, the immune system mistakenly targets the body's own cells, leading to autoimmune diseases. Antimitochondrial antibodies are one such type of autoantibody.

Association with Primary Biliary Cholangitis

The presence of AMAs is a hallmark of primary biliary cholangitis, a disease characterized by the slow, progressive destruction of the liver's small bile ducts. These antibodies are found in 90-95% of people with PBC, and in 50% of their family members, suggesting a genetic predisposition.

Detection

AMAs can be detected through a blood test. The presence of these antibodies, along with symptoms and other test results, can help diagnose PBC and other autoimmune conditions.

Other Associations

While most commonly associated with PBC, AMAs can also be found in a small percentage of people with other autoimmune diseases, such as systemic lupus erythematosus and rheumatoid arthritis. However, the role of these antibodies in these diseases is not well understood.

See Also

• Autoimmune disease
• Primary biliary cholangitis
• Mitochondria