Actin (Smooth Muscle) Antibody (IgG)
Also known as: Anti-Smooth Muscle Ab IgG, ASMA IgG, F-Actin Antibody, Smooth Muscle Antibody IgG
Use
Detection of immunoglobulin G (IgG) class autoantibodies targeting smooth muscle actin (“actin, smooth muscle”) supports evaluation for autoimmune liver disorders—most notably autoimmune hepatitis type 1. High titers are commonly associated with autoimmune hepatitis (~75% of cases), autoimmune cholangitis (~65%), and less frequently primary biliary cirrhosis (~30%), while low occurrence (~2%) may be seen in healthy individuals ([nordx.testcatalog.org](https://nordx.testcatalog.org/show/SMABS-15043-Q?utm_source=openai)).
Special Instructions
Not provided.
Limitations
Interpretation should consider that low-level positives may occur in healthy individuals; false positives possible. Not diagnostic in isolation; results should be interpreted in clinical context along with other liver function and autoimmune markers ([nordx.testcatalog.org](https://nordx.testcatalog.org/show/SMABS-15043-Q?utm_source=openai)).
Methodology
Immunoassay (ELISA)
Biomarkers
LOINC Codes
- 44706-0
Result Turnaround Time
2 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
0.5 mL
Minimum Volume
0.25 mL
Container
Serum Separator Tube (SST)
Collection Instructions
Spin specimen, separate from clot and send refrigerated in a plastic, screw-capped vial.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 14 Days |
| Refrigerated | 14 Days |
| Frozen | 30 Days |
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