Antiplatelet antibody test
This test looks for platelet antibodies in your blood in order to find out the cause of a low platelet count.
Platelets are the part of your blood mainly responsible for clotting. They are made in your bone marrow along with white and red blood cells. Platelets are actually just fragments of cells and make up a small portion of your blood volume, but they have an important health function.
If you have platelet antibodies in your blood, it means your immune system is mistakenly creating antibodies to attack the platelets in your blood. People with idiopathic thrombocytopenic purpura or systemic lupus erythematosus may have platelet antibodies.
If antibodies have destroyed a considerable amount of your platelets, your doctor may diagnose thrombocytopenia, which means you have an abnormally low platelet count. Sometimes taking blood thinning medications can lead to a condition called drug-induced thrombocytopenia.
You may have this test if you have a low platelet count or have symptoms that may mean that your production of platelets has been disrupted in some way. Symptoms of a low platelet count include:
Skin that bruises easily
Wound that bleeds longer than normal
For women, heavy menstrual bleeding
Your doctor may also order other blood tests, such as a platelet count.
Many things may affect your lab test results. These include the method each lab 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.
A normal result is negative, meaning you have no platelet antibodies. A positive result means that platelet antibodies have been found in your blood. It may mean that your blood may not be able to clot the way it should.
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.
Taking anticoagulant drugs, or blood thinners, for another condition may affect your results.
You don't need to prepare for this test. But be sure your doctor knows about all medicines, herbs, vitamins, and supplements you are taking. This includes medicines that don't need a prescription and any illicit drugs you may use.