This test looks for substances called antimitochondrial antibody and antimitochondrial M2 antibody in your blood.
These substances are usually made by your body if you have a condition called primary biliary cirrhosis (PBC). PBC is the most common autoimmune disease that affects the liver. In autoimmune diseases, the immune system attacks organs or tissues in the body. Antimitochondrial antibody is found in nearly 19 in 20 people with PBC.
PBC causes damage to ducts in the liver that drain away fluid called bile. As a result bile builds up in the liver. This scars the liver. This scarring keeps the liver from working as it should. Over time, it causes liver failure.
PBC is especially common in middle-aged women. It often strikes along with other autoimmune diseases, especially Sjögren syndrome.
PBC is usually diagnosed and treated early in the course of the disease. This is good, because early treatment can slow down liver scarring. It delays liver failure.
Mitochondrial (M2) Antibody
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