Platelet Antibody

Does this test have other names?

Antiplatelet antibody test

What is this 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. They make up a small part 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 healthcare provider may diagnose thrombocytopenia. This means you have an abnormally low platelet count. Sometimes taking blood-thinning medicines can lead to a condition called drug-induced thrombocytopenia.  

Why do I need this test?

You may need this test if you have a low platelet count. You may also have this test if you 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

• Frequent nosebleeds

• For women, heavy menstrual bleeding

What other tests might I have along with this test?

Your healthcare provider may also order other blood tests. If you have bleeding or anemia, you may need a platelet count or complete blood cell count (CBC).

What do my test results mean?

Test results may vary depending on your age, gender, health history, the method used for the test, and other things. Your test results may not mean you have a problem. Ask your healthcare provider what your test results mean for you. 

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.

How is this test done?

The test is done with a blood sample. A needle is used to draw blood from a vein in your arm or hand. 

Does this test pose any risks?

Having a blood test with a needle carries some risks. These include bleeding, infection, bruising, and feeling lightheaded. When the needle pricks your arm or hand, you may feel a slight sting or pain. Afterward, the site may be sore. 

What might affect my test results?

Taking blood-thinning medicine (anticoagulants) for another condition may affect your results.

How do I get ready for this test?

You don't need to prepare for this test. But be sure your healthcare provider 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.