What is thrombocytopenia?

Thrombocytopenia (THROM-bo-sigh-toe-PEE-ne-ah) occurs when your blood platelet count is low. Platelets are also called thrombocytes. This type of blood cell clumps together to form blood clots to help stop bleeding at the site of a cut or wound. Another name for a blood clot is thrombus.

Bone marrow is the soft, spongy tissue inside bones that makes all blood cells including platelets. People who have thrombocytopenia don’t have enough platelets to form a blood clot. If you get a cut or other injury, you may bleed too much and the bleeding can be hard to stop.

Who might get thrombocytopenia?

Thrombocytopenia can affect people of all ages, races and genders. For unknown reasons, approximately 5% of pregnant women develop mild thrombocytopenia right before childbirth.

What are the types of thrombocytopenia?

The three main classes of thrombocytopenia are:

  • Platelet destruction such as with an auto-antibody that attaches to the platelet surface.
  • Platelet sequestration such as in someone with a large spleen or with liver disease.
  • Decreased platelet production as occurs in certain bone marrow diseases.

How common is thrombocytopenia?

It’s unknown how many people have thrombocytopenia. Many people have mild symptoms. They might not even know they have the condition. The autoimmune form of thrombocytopenia, immune thrombocytopenic purpura or ITP, affects approximately three to four out of every 100,000 adults and children.

What causes thrombocytopenia?

In rare instances, thrombocytopenia is inherited, or passed from parent to child. More commonly, certain disorders, conditions and medications cause a low platelet count. These include:

  • Alcohol use disorder and alcoholism.
  • Autoimmune disease which causes ITP. ITP is sometimes associated with other autoimmune conditions such as lupus.
  • Bone marrow diseases, including aplastic anemia, leukemia, certain lymphomas and myelodysplastic syndromes.
  • Cancer treatments like chemotherapy and radiation therapy.
  • Enlarged spleen caused by cirrhosis of the liver or Gaucher disease. The enlarged spleen traps platelets and other blood cells and prevents them from circulating in the blood stream.
  • Exposure to toxic chemicals, including arsenic, benzene and pesticides.
  • Medications to treat bacterial infections (antibiotics), seizures (epilepsy) and heart problems, or the blood thinner heparin.
  • Viruses, such as hepatitis C, CMV, EBV and HIV.

What are the symptoms of thrombocytopenia?

Some people with mild cases of thrombocytopenia don’t have symptoms. Often, one of the first signs is a cut or nosebleed that won’t stop bleeding. Other signs of low platelet count include:

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