Immune Thrombocytopenia (ITP)

Reviewed/Revised Sep 2023
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What is immune thrombocytopenia (ITP)?

Thrombocytes are platelets, which are small cells that circulate in your bloodstream and help blood clot. Thrombocytopenia is having too few platelets in your blood.

Immune thrombocytopenia is when you have too few platelets because your own immune system destroyed them.

  • With too few platelets, you bleed easily

  • You may have tiny purple spots on your skin and get nosebleeds and bleeding gums

  • Doctors diagnose ITP with blood tests

  • In children, ITP usually goes away on its own

  • Adults with ITP may get corticosteroids or other medicines to slow down their immune system

  • If you're an adult and medicines don't work, doctors may take out your spleen

What causes ITP?

ITP happens when your immune system makes antibodies that attack and destroy your platelets. Doctors don’t know why this happens, but in children it often happens after a virus.

What are the symptoms of ITP?

Symptoms of ITP can develop suddenly or slowly. You may have:

  • Tiny red spots on your skin or inside your mouth

  • Bruises after very minor injuries

  • Bleeding gums

  • Heavy menstrual periods

You're more likely to bleed the lower your platelet count drops. People who have very few platelets may bleed heavily from their intestines or have life-threatening bleeding in their brain.

How can doctors tell if I have ITP?

Doctors do:

  • Blood tests to count the number of platelets in a sample of blood

  • Tests to look for other causes of a low platelet count

Rarely, doctors take a small sample of your bone marrow (bone marrow biopsy) to find out how well your body is producing platelets.

How do doctors treat ITP?

Doctors treat ITP with:

  • Corticosteroids

  • Medicine to help your body make more platelets

  • Medicine to slow down your immune system

  • Rarely, surgery to remove your spleen (splenectomy)

If you have life-threatening bleeding, doctors may give you a platelet transfusion. Platelet transfusions don't usually work well because the antibodies in your blood attack the transfused platelets too.

Removing the spleen can help keep more platelets circulating in the blood.

In adults, ITP is usually long-lasting, but in children it often gets better on its own.

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