Autoimmune liver disease panel
An autoimmune liver disease panel is a series of tests performed when autoimmune liver disease is suspected. These tests include anti-smooth muscle antibodies, anti-mitochondrial antibodies, and anti-nuclear antibodies.
How the test is performed
Blood is drawn from a vein (venipuncture), usually from the inside of the elbow or the back of the hand. The puncture site is cleaned with antiseptic, and a tourniquet or blood pressure cuff is placed around the upper arm to apply pressure and restrict blood flow through the vein. This causes veins below the tourniquet to fill with blood.
A needle is inserted into the vein, and the blood is collected in an air-tight vial or a syringe. During the procedure, the tourniquet is removed to restore circulation. Once the blood has been collected, the needle is removed, and the puncture site is covered to stop any bleeding.
For an infant or small child, the area is cleansed with antiseptic and punctured with a sharp needle or a lancet. The blood may be collected in a pipette (small glass tube), on a slide, onto a test strip, or into a small container. Cotton or a bandage may be applied to the puncture site if there is any continued bleeding.
The specimen is then sent to the laboratory for evaluation.
How to prepare for the test
No special preparation is necessary for this test.
Infants and children:
The physical and psychological preparation you can provide for this or any test or procedure depends on your child’s age, interests, previous experience, and level of trust. For specific information regarding how you can prepare your child, see the following topics as they correspond to your child’s age:
- Infant test or procedure preparation (birth to 1 year)
- Toddler test or procedure preparation (1 to 3 years)
- Preschooler test or procedure preparation (3 to 6 years)
- Schoolage test or procedure preparation (6 to 12 years)
- Adolescent test or procedure preparation (12 to 18 years)
How the test will 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 the test is performed
Autoimmune disorders, in which cells from the immune system attack certain tissues and/or organs, are one possible cause of liver disease. This group of tests assists your health care provider in the diagnosis of liver disease (see hepatitis).
The normal range for protein levels in the blood will vary with each laboratory. Please check with your health care provider for the normal ranges in your particular laboratory.
- Negative test result for anti-nuclear antibodies
- Negative test result for anti-mitochondrial antibodies
- Negative test result for anti-smooth muscle antibodies
- Negative anti-liver kidney microsomal antibodies
What abnormal results mean
If the test is positive for anti-nuclear, anti-smooth muscle, or anti-liver kidney microsomal antibodies, autoimmune hepatitis or other liver disease involving the immune system may be the cause of liver problems.
If the test is positive for anti-mitochondrial antibodies, there is a high probability of primary biliary cirrhosis.
If the globulins are elevated and albumin is decreased, hepatic cirrhosis or chronic active hepatitis may be present.
What the risks are
Risks associated with venipuncture are slight and include the following:
- Excessive bleeding
- Fainting or feeling lightheaded
- Hematoma (blood accumulating under the skin)
- Infection (a slight risk any time the skin is broken)
- Multiple punctures to locate veins
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 may be more difficult for you or your child than for others.
by Janet G. Derge, M.D.