(thrombocytopathy) Qualitative disorder of the blood platelets, due mainly to deficiency of platelet factor 3.

(platelet disorder) A disorder of platelet function or platelet production that may cause increased bleeding.

(platelet disorder) Disorders caused by abnormalities in platelet count or function.

(platelet disorders) Platelets, also known as thrombocytes, are blood cells. They form in your bone marrow, a sponge-like tissue in your bones. Platelets play a major role in blood clotting. Normally, when one of your blood vessels is injured, you start to bleed. Your platelets will clot (clump together) to plug the hole in the blood vessel and stop the bleeding. You can have different problems with your platelets: If your blood has a low number of platelets, it is called thrombocytopenia. This can put you at risk for mild to serious bleeding. The bleeding could be external or internal. There can be various causes. If the problem is mild, you may not need treatment. For more serious cases, you may need medicines or blood or platelet transfusions.; If your blood has too many platelets, you may have a higher risk of blood clots. When the cause is unknown, this is called thrombocythemia. It is rare. You may not need treatment if there are no signs or symptoms. In other cases, people who have it may need treatment with medicines or procedures.; If another disease or condition is causing the high platelet count, it is thrombocytosis. The treatment and outlook for thrombocytosis depends on what is causing it. Another possible problem is that your platelets do not work as they should.

Platelets are cell fragments that function in the clotting system. Thrombopoietin helps control the number of circulating platelets by stimulating the bone marrow to produce megakaryocytes, which in turn shed platelets from their cytoplasm. Thrombopoietin is produced in the liver at a constant rate and its circulating level is determined...

The hemostatic system consists of platelets, coagulation factors, and the endothelial cells lining the blood vessels. The platelets arise from the fragmentation of the cytoplasm of megakaryocytes in the bone marrow and circulate in blood as disc-shaped anucleate particles for 7-10 days.

Thrombocytopathy, any of several blood disorders characterized by dysfunctional platelets (thrombocytes), which result in prolonged bleeding time, defective clot formation, and a tendency to hemorrhage. Inherited thrombocytopathies include von Willebrand disease; thrombasthenia, characterized by...