LAB TEST
Platelet aggregation test
The platelet aggregation blood test checks how well platelets, a part of blood, clump together and cause blood to clot.
How the Test is Performed
A blood sample is needed. The laboratory specialist will look at how the platelets spread out in the liquid part of the blood (plasma) and whether they form clumps after a certain chemical or drug is added. When platelets clump together, the blood sample is clearer. A machine measures the changes in cloudiness and…
How to Prepare for the Test
Your health care provider may tell you to temporarily stop taking medicines that may affect the test results. Be sure to tell your provider about all the medicines you take. These include: Antibiotics Antihistamines Antidepressants Blood thinners, such as aspirin, that make it hard for the blood to clot Nonsteroidal…
How the Test will Feel
When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or bruising. This soon goes away.
Why the Test is Performed
Your provider may order this test if you have signs of a bleeding disorder or a low platelet count . It may also be ordered if a member of your family is known to have a bleeding disorder due to platelet dysfunction. The test can help diagnose problems with platelet function. It may determine whether the problem is…
Normal Results
The normal time it takes for platelets to clump depends on temperature, and may vary from laboratory to laboratory. Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or may test different specimens. Talk to your provider about the meaning of your specific test…
What Abnormal Results Mean
Decreased platelet aggregation may be due to: Autoimmune disorders that produce antibodies against platelets Fibrin degradation products Inherited platelet function defects Medicines that block platelet aggregation Bone marrow disorders Uremia (a result of kidney failure ) Von Willebrand disease (a bleeding disorder)
Risks
There is little risk involved with having your blood taken. Veins and arteries vary in size from one person to another, and from one side of the body to the other. Taking blood from some people may be more difficult than from others. Other risks associated with having blood drawn are slight, but may include: Excessive…
References
Pai M, Moffat KA. Laboratory evaluation of hemostatic and thrombotic disorders. In: Hoffman R, Benz EJ, Silberstein LE, et al, eds. Hematology: Basic Principles and Practice . 8th ed. Philadelphia, PA: Elsevier; 2023:chap 127. Rao AK, Songdej N, Di Paola JA. Platelet disorders and von Willebrand disease. In: McPherson…
This is a summary. Read the full article at www.ucsfbenioffchildrens.org (reviewed 02/02/2023).
This page is general information and is not medical advice. It does not replace a registered doctor, and it is not a prescription or a recommendation to use any medicine or test. Prices are listed prices and may change. Always follow the advice of your doctor or pharmacist.