Laboratory Services

Antimitochondrial (M2) Antibody

Print this page

Updated Test Information:

Test Description
Antimitochondrial (M2) Antibody

AMA, Mitochondrial Antibody

Test ID
General Information

Antimitochondrial antibodies are important diagnostic indicators for patients with Primary Biliary Cirrhosis (PBC), chronic active hepatitis, cryptogenic cirrhosis, as well as in those with clinical but no biochemical evidence of liver disease. The mitochondrial M2 antigen has a 95% specificity for PBC. Assay results should be used in conjunction with clinical findings and other serological tests.

Specimen Type


Alternate Specimen Type

Plasma (Li-Heparin or EDTA)

Specimen Requirements


Additional Processing Details

Caution: Serum/plasma samples are not to be repeatedly frozen and thawed, since this can cause analyte deterioration. They are to be thawed only once.


Stored at 22˚C: 8 hrs
Stored at 2-8˚C: 48 hrs
If assays are not completed within 48 hrs or the specimen is to be stored beyond 48 hrs, the serum/plasma should be frozen at or below -20˚C.

Unacceptable Specimen Conditions

Lipemic, hemolyzed or microbially contaminated samples.


Fluorescent enzyme immunoassay (FEIA)

Estimated TAT

2-5 days

Testing Schedule

Monday-Saturday, alternating days

CPT Code(s)


Minimum Sample Volume

1 mL

Pediatric Min. Volume (if applicable)

500 uL

Reference Range
  Negative Equivocal Positive
Antimitochondrial (M2) AB <4 4-6 >6  U/ml
Performing Lab

Incyte Diagnostics

LOINC Code(s)