Actin (Smooth Muscle) Antibody (ASMA) Blood Test
The ASMA Blood Test assists in the detection of antibodies and will aid in the diagnosis of autoimmune liver diseases such as autoimmune hepatitis (AIH) and primary biliary cirrhosis (PBC).
Description
The actin (Smooth Muscle) antibody (ASMA) blood test detects if the smooth muscle antibody is in the blood and assists in the evaluation of the condition of a person with hepatitis. An ASMA test is useful to determine if the liver inflammation is autoimmune or not. In addition, the test is used to diagnose autoimmune hepatitis and also the separation of autoimmune liver damage from other reasons. Smooth muscle antibodies are proteins that are produced by the body’s immune system. The ASMAs attack several structural proteins in smooth muscle, which affect the liver and other tissues.
The results of an ASMA test are either normal or abnormal. Normal results indicate that there are no antibodies present or only a trace amount. Abnormal results indicate that a higher amount of ASMA is in the blood and may be due to:
- an autoimmune liver disease
- infectious mononucleosis
- chronic hepatitis C infection
- a melanoma
- cancer of the breast or ovaries
People with autoimmune hepatitis often have other autoantibodies. These include:
- Antiactin antibodies
- Antinuclear antibodies
- Anti-soluble liver antigen/liver pancreas (anti-SLA/LP) antibodies
The test also helps distinguish autoimmune hepatitis from systemic lupus erythematosus.