If your doctor thinks that you have excessive blood clotting based on your signs and symptoms, he or she will look for the cause of the condition.
Your doctor will ask about your medical and family histories, do a physical exam, and review the results from tests.
Your primary care doctor may refer you to a hematologist. This is a doctor who specializes in diagnosing and treating blood diseases and disorders.
Your doctor may ask you detailed questions about your medical history and your family's medical history. He or she may ask whether you or a blood relative:
Your doctor will do a physical exam to see how severe your blood clotting problem is and to look for a possible cause.
Your doctor may recommend blood tests to look at your blood cells and the clotting process. If he or she thinks you have a genetic condition, you may need more blood tests.
Tests to find the cause of excessive blood clotting might be delayed for weeks or even months while you receive treatment for a blood clot.
Initial blood tests will include a complete blood count and a platelet count. These tests measure the number of red blood cells, white blood cells, and platelets in your blood.
In this situation, your doctor will want to know the number of platelets in your blood. Platelets are blood cell fragments that stick together to form clots.
You also may need blood tests that look at the proteins active in the blood clotting process and how long it takes them to form a blood clot.
Clotting proteins or factors react with each other along two pathways called the intrinsic and extrinsic pathways. (A pathway is a string of chemical reactions that always occur in a certain order.) The two pathways join in a common pathway to make a fibrin network that holds blood clots together.
If your doctor thinks your blood clotting condition is genetic, you may need other blood tests. For example, you might need tests to check:
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