Cardiolipin antibodies (IgG, IgM, IgA), anticardiolipin
A cardiolipin antibodies test measures the concentration of the antibodies IgG (immunoglobulin G), IgA (immunoglobulin A), and IgM (immunoglobulin M) as they relate to the amount of cardiolipins. Cardiolipin is a phospholipid, or lipid (fat) molecule, in the blood. The levels of these antibodies are often high in people with abnormal blood clotting, autoimmune diseases like lupus, or repeated miscarriages.
Your health care provider may order a cardiolipin antibodies test if you are having frequent and abnormal blood clot formation or abnormal bleeding. If you have had frequent miscarriages, the test might help doctors figure out why. Finally, some autoimmune diseases, such as lupus, are related to the presence of cardiolipin antibodies in the blood. This test may be used to help diagnose the particular disease. When high levels of cardiolipins are found in people with these or other issues, it is known as cardiolipin antibody syndrome. This test helps diagnose this condition.
The cardiolipin antibodies test is usually just one of many tests given. The tests you get will depend on what your health care provider is looking for. For example, if your doctor suspects that you have lupus, you will probably need other blood tests, as well as imaging studies and tissue biopsies.
A result for a lab test may be affected by many things, including the method the laboratory uses to do the test. Even if your test results are different from the normal value, you may not have a problem. To learn what the results mean for you, talk with your health care provider.
The results of a cardiolipin antibodies test are easy to understand. If you're negative for cardiolipin antibodies, that is normal. If you're positive, you might have cardiolipin antibody syndrome and will probably be retested to see if the antibody stays in your blood.
The test requires a blood sample, which is drawn through a needle from a vein in your arm.
Taking a blood sample with a needle carries risks that include bleeding, infection, bruising, or feeling dizzy. When the needle pricks your arm, you may feel a slight stinging sensation or pain. Afterward, the site may be slightly sore.
Although cardiolipin antibodies are commonly related to lupus, a positive test for them doesn't mean you have lupus. Other tests will be needed to confirm the diagnosis. When you have problems related to blood clotting, miscarriages, or other issues, this test result can help health care providers figure out the best way to treat your condition.
You don't need to prepare for this test.