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Treatment Idiopathic Thrombocytopenic Purpura

Idiopathic thrombocytopenic purpura (ITP) is a bleeding disorder in which the blood does not clot as it should. This is due to a low number of blood cell fragments called platelets.

Platelets also are called thrombocytes. They're made in your bone marrow along with other kinds of blood cells. Platelets stick together (clot) to seal small cuts or breaks on blood vessel walls and stop bleeding.

"Idiopathic" means that the cause of the condition is not known. "Thrombocytopenic" means there is a lower-than-normal number of platelets in the blood. "Purpura" refers to purple bruises caused by bleeding in small blood vessels under the skin.

A person who has ITP also may have bleeding that results in tiny red or purple dots on the skin. These pinpoint-sized dots are called petechiae. Petechiae may look like a rash.


The photograph shows petechiae (red/purple dots) and purpura (bruises) in the skin. Bleeding under the skin causes the purple, brown, and red color of the petechiae and purpura.

Types of ITP

There are two types of ITP: acute (temporary or short-term) ITP and chronic (long-lasting) ITP.

  • Acute ITP generally lasts less than 6 months. It mainly occurs in children, both boys and girls, and is the most common type of ITP. It typically occurs following an infection caused by a virus. This type of ITP often goes away on its own within a few weeks or months and does not return. Treatment may not be needed.
  • Chronic ITP is a long-lasting (6 months or longer) type of ITP that mostly affects adults. However, some teenagers and even younger children get this type of ITP. Chronic ITP affects women two to three times more often than men.


Having a low platelet count doesn’t cause symptoms. However, the bleeding that a low platelet count can cause may have the following signs and symptoms:

  • Pinpoint red spots on the skin that often are found in groups and may look like a rash. The spots, called petechiae, are due to bleeding under the skin.
  • Bruising or purplish areas on the skin or mucous membranes (such as in the mouth) due to bleeding under the skin. The bruises may occur for no known reason. This type of bruising is called purpura. More extensive bleeding can cause hematomas. A hematoma is a collection of clotted or partially clotted blood under the skin. It looks or feels like a lump.
  • Nosebleeds or bleeding from the gums (for example, when dental work is done).
  • Blood in the urine or stool (bowel movement).

Any kind of bleeding that's hard to stop could be a sign of ITP. This includes menstrual bleeding in women that’s heavier than usual.

Bleeding in the brain is rare, and the symptoms of bleeding in the brain may vary in severity.

A low number of platelets doesn't cause pain, fatigue (tiredness), problems concentrating, or any other symptoms.


To diagnose ITP, doctors use your medical history, a physical exam, and blood tests that usually include:

  • A complete blood count. This test shows the numbers of different kinds of blood cells, including platelets, in a small sample of your blood. In ITP, the red and white blood cell counts are normal.
  • A blood smear. During this test, some of your blood is put on a slide. A microscope is then used to look at your platelets and other blood cells. In ITP, the number of platelets is lower than normal.

You also may have a blood test to check for the antibodies that attack platelets.

If blood tests show that you have a low number of platelets, your doctor may recommend more tests to confirm a diagnosis of ITP. For example, bone marrow tests may be used to see whether your bone marrow is making platelets.


In most cases, it's believed that an autoimmune response causes idiopathic thrombocytopenic purpura (ITP).

Normally, the immune system makes antibodies (proteins) to fight off germs or other harmful things that enter the body. In ITP, however, the immune system attacks and destroys the body's platelets by mistake. Why this happens isn't known.

Children who get acute (short-term) ITP often have had recent viral infections. It's possible that the infection somehow "triggers" or sets off the immune reaction that leads to ITP in these children. ITP in adults, on the other hand, doesn't seem to be linked to infections.



National Heart, Lung, and Blood Institute, USA.