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Platelet Disorders
Summary
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. For example, in von Willebrand Disease, your platelets cannot stick together or cannot attach to blood vessel walls. This can cause excessive bleeding. There are different types of in von Willebrand Disease; treatment depends on which type you have.
NIH: National Heart, Lung, and Blood Institute
National Heart, Lung, and Blood Institute
Encyclopedia
- Acquired platelet function defect Medical Encyclopedia
- Blood clotting Medical Encyclopedia
- Factor VIII assay Medical Encyclopedia
- Platelet associated antibodies Medical Encyclopedia
- Platelet count Medical Encyclopedia
- Thrombotic thrombocytopenic purpura Medical Encyclopedia
- Von Willebrand disease Medical Encyclopedia
Genetics
- Atypical hemolytic-uremic syndrome: MedlinePlus Genetics National Library of Medicine
- Bernard-Soulier syndrome: MedlinePlus Genetics National Library of Medicine
- Dyserythropoietic anemia and thrombocytopenia: MedlinePlus Genetics National Library of Medicine
- Essential thrombocythemia: MedlinePlus Genetics National Library of Medicine
- Glanzmann thrombasthenia: MedlinePlus Genetics National Library of Medicine
- Gray platelet syndrome: MedlinePlus Genetics National Library of Medicine
- Hermansky-Pudlak syndrome: MedlinePlus Genetics National Library of Medicine
- Immune thrombocytopenia: MedlinePlus Genetics National Library of Medicine
- Jacobsen syndrome: MedlinePlus Genetics National Library of Medicine
- MYH9-related disorder: MedlinePlus Genetics National Library of Medicine
- Thrombotic thrombocytopenic purpura: MedlinePlus Genetics National Library of Medicine
- Von Willebrand disease: MedlinePlus Genetics National Library of Medicine
- X-linked thrombocytopenia: MedlinePlus Genetics National Library of Medicine
Patient Handouts
- Bleeding time Medical Encyclopedia
- Congenital platelet function defects Medical Encyclopedia
- Drug-induced thromobocytopenia Medical Encyclopedia
- Essential thrombocythemia Medical Encyclopedia
- Glanzmann disease Medical Encyclopedia
- Idiopathic thrombocytopenic purpura (ITP) Medical Encyclopedia
- Partial thromboplastin time (PTT) Medical Encyclopedia
- Platelet aggregation test Medical Encyclopedia
- Purpura Medical Encyclopedia
- Thrombocytopenia Medical Encyclopedia
Diagnosis and Tests
- Blood Tests National Heart, Lung, and Blood Institute
- MPV Blood Test National Library of Medicine
- Platelet Tests National Library of Medicine
Clinical Trials
- ClinicalTrials.gov: Blood Platelet Disorders National Institutes of Health
- ClinicalTrials.gov: Thrombocytopenia National Institutes of Health
- ClinicalTrials.gov: von Willebrand Diseases National Institutes of Health
Find an Expert
- Find a Hematologist American Society of Hematology
- National Heart, Lung, and Blood Institute National Heart, Lung, and Blood Institute
Specifics
- Heparin-Induced Thrombocytopenia American Heart Association
- Immune thrombocytopenia (ITP) Mayo Foundation for Medical Education and Research
- Immune Thrombocytopenia (ITP) National Heart, Lung, and Blood Institute
- Inherited Platelet Disorders World Federation of Hemophilia
- Petechiae Mayo Foundation for Medical Education and Research
- Thrombocythemia and Thrombocytosis National Heart, Lung, and Blood Institute
- Thrombocytopenia National Heart, Lung, and Blood Institute
- Thrombocytosis Mayo Foundation for Medical Education and Research
- Thrombotic Thrombocytopenic Purpura (TTP) National Heart, Lung, and Blood Institute
Children
- Immune Thrombocytopenia (For Parents) Nemours Foundation
- von Willebrand Disease (For Parents) Nemours Foundation
Start Here
- Platelets: What Is Their Function and Why Are They Important Cleveland Clinic Foundation
- What Are Platelet Disorders? National Heart, Lung, and Blood Institute
Journal Articles
Related Issues
- Selected Adverse Events Reported after COVID-19 Vaccination Centers for Disease Control and Prevention
- What Are Bleeding Disorders National Heart, Lung, and Blood Institute
Treatments and Therapies
- Splenectomy Mayo Foundation for Medical Education and Research
- Treatments for Blood Disorders National Heart, Lung, and Blood Institute