Anti-mitochondrial antibody (AMA) was first discovered by Maokey in the serum of patients with primary biliary cirrhosis (PBC) in 1958. It is an autoantibody that is organ-free and species-specific. AMA is also found in other autoimmune patients. The target antigen of AMA is a variety of proteins on the mitochondrial membrane, and the composition is complicated. It is known that there are M1 to M99 components. M1 is a cardiolipin of the mitochondrial outer membrane; M2 is the main component of the AMA reaction in the serum of PBC patients, and its essence is a complex of pyruvate dehydrogenase and α-ketoacid dehydrogenase on the mitochondrial inner membrane; the essence of M3 is still It is not clear; M4 is a sulfite oxidase; M5 is a 65kD protein; the properties of M6, M7, M8 are unknown; M9 is a glycogen phosphorylase.

Basic Information

Specialist classification: Digestive examination classification: blood examination

Applicable gender: whether men and women apply fasting: fasting

Analysis results:

Below normal:

Normal value:
no

Above normal:

negative:
normal.

Positive:
Positive found in: primary biliary cirrhosis. More than 50% of these patients have titers of serum anti-mitochondrial antibodies (ie, multiples of serum dilution) ranging from 1:200 to 1:3200. In addition, autoimmune diseases such as systemic lupus erythematosus, rheumatoid arthritis, progressive systemic sclerosis, and Sjogren's syndrome are also positive.

Tips: Because the patient needs to take some blood, the patient needs to undergo an empty stomach examination. Normal value

Normal human serum AMA is negative.

Clinical significance

Abnormal results are currently not included in anti-mitochondrial antibodies due to anti-M1 antibodies, anti-cardiolipin antibodies. Anti-M2 is found in 90% of patients with PBC, and is often used as an important laboratory diagnostic indicator for the disease, but there is no correlation between AMA and PBC disease duration, disease severity, and treatment effect. In addition to PBC, anti-M2 is also found in chronic active hepatitis (CAH), HBsAg-negative liver disease. Anti-M2AMA is seen in patients with pseudo-lupus erythematosus (PLE) syndrome induced by pyrazolone series. Anti-M4AMA is also found in PBC; anti-M9 is found in early PBC; anti-M5 is found in SLE, autoimmune hemolytic anemia; anti-M6 is found in Hepatitis induced by iproniazid (a monoamine oxidase inhibitor); anti-M7 occurs in some patients with unexplained cardiomyopathy, whose target antigen is organ-specific and is present in the mitochondria of cardiomyocytes. Due to the complex composition of mitochondrial antigens, the nature of many antigens is not known, and almost all patients with primary biliary cirrhosis have high titers of anti-M2AMA. Therefore, the current AMA (or anti-M2AMA) assay is mainly used for the diagnosis of PBC.

Patients with PBC, patients with lupus erythematosus (PLE) syndrome, and patients with primary biliary cirrhosis need to be examined.

Positive results may be diseases: biliary cirrhosis, primary intrahepatic sclerosis syndrome, primary sclerosing cholangitis, hyperthyroidism, hepatitis B precautions

Contraindications before the examination: Because the patient needs to take some blood, the patient needs to undergo an empty stomach examination.

Requirements for examination: AMA is often used as an auxiliary diagnosis for the cause of jaundice and liver disease. It can be used as a basis for differential diagnosis of primary biliary cirrhosis and extrahepatic biliary obstructive cirrhosis. The doctor should pay attention to his diagnosis according to the examination process.

Inspection process

Laboratory Description: Anti-mitochondrial antibody (AMA) is an autoantibody that occurs primarily in the serum of patients with primary or biliary cirrhosis.

Inspection method: indirect fluorescent antibody method.

Not suitable for the crowd

Not suitable for the crowd: generally no special population.

Adverse reactions and risks

There are no related complications.