Anti-smooth muscle antibody
Anti-smooth muscle antibody is a blood test that detects the presence of antibodies against smooth muscle.
How is the Test Performed?
A blood sample is needed. This may be taken through a vein. The procedure is called a venipuncture.
Preparation for the Test
No special preparation is needed.
How will the Test Feel?
When the needle is inserted to draw blood, some people feel moderate pain, while others feel only a prick or stinging sensation. Afterward, there may be some throbbing.
Why is the Test Performed?
Normal Results for Anti-smooth muscle antibody
Normally, there are no antibodies present.
Note: Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.
What Abnormal Results Mean
A positive test may be due to:
- Chronic active hepatitis
- Infectious mononucleosis
Anti-smooth muscle antibody Risks
Veins and arteries vary in size from one patient to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others.
Other risks associated with having blood drawn are slight but may include:
- Excessive bleeding
- Fainting or feeling light-headed
- Hematoma (blood accumulating under the skin)
- Infection (a slight risk any time the skin is broken)
|Review Date: 2/11/2013
Reviewed By: Ariel D. Teitel, MD, MBA, Clinical Associate Professor of Medicine, NYU Langone Medical Center. Review provided by VeriMed Healthcare Network. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, Bethanne Black, Stephanie Slon, and Nissi Wang.