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URL of this page: https://medlineplus.gov/plateletdisorders.html
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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
Diagnosis and Tests
- Blood Tests (National Heart, Lung, and Blood Institute) Also in Spanish
- MPV Blood Test (National Library of Medicine) Also in Spanish
- Platelet Tests (National Library of Medicine) Also in Spanish
Treatments and Therapies
- Splenectomy (Mayo Foundation for Medical Education and Research) Also in Spanish
- Treatments for Blood Disorders (National Heart, Lung, and Blood Institute) Also in Spanish
Related Issues
- What Are Bleeding Disorders (National Heart, Lung, and Blood Institute) Also in Spanish
Specifics
- Immune thrombocytopenia (ITP) (Mayo Foundation for Medical Education and Research)
- Immune Thrombocytopenia (ITP) (National Heart, Lung, and Blood Institute) Also in Spanish
- Inherited Platelet Disorders (World Federation of Hemophilia)
- Petechiae (Mayo Foundation for Medical Education and Research) Also in Spanish
- Thrombocythemia and Thrombocytosis (National Heart, Lung, and Blood Institute) Also in Spanish
- Thrombocytopenia (National Heart, Lung, and Blood Institute)
- Thrombocytosis (Mayo Foundation for Medical Education and Research) Also in Spanish
- Thrombotic Thrombocytopenic Purpura (TTP) (National Heart, Lung, and Blood Institute) Also in Spanish
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)
Videos and Tutorials
- Blood clotting (Medical Encyclopedia) Also in Spanish
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)
Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine)
Find an Expert
- Find a Hematologist (American Society of Hematology)
- National Heart, Lung, and Blood Institute
Children
- Immune Thrombocytopenia (For Parents) (Nemours Foundation) Also in Spanish
- von Willebrand Disease (Nemours Foundation) Also in Spanish
Patient Handouts
- Bleeding time (Medical Encyclopedia) Also in Spanish
- Congenital platelet function defects (Medical Encyclopedia) Also in Spanish
- Drug-induced thromobocytopenia (Medical Encyclopedia) Also in Spanish
- Essential thrombocythemia (Medical Encyclopedia) Also in Spanish
- Glanzmann thrombasthenia (Medical Encyclopedia) Also in Spanish
- Idiopathic thrombocytopenic purpura (ITP) (Medical Encyclopedia) Also in Spanish
- Partial thromboplastin time (PTT) (Medical Encyclopedia) Also in Spanish
- Platelet aggregation test (Medical Encyclopedia) Also in Spanish
- Purpura (Medical Encyclopedia) Also in Spanish
- Thrombocytopenia (Medical Encyclopedia) Also in Spanish
The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health.