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In this Article

• What is idiopathic thrombocytopenic purpura (ITP)?
• What are the types of idiopathic thrombocytopenic purpura?
• What are the causes of idiopathic thrombocytopenic purpura (ITP)?
• What are the risk factors for idiopathic thrombocytopenic purpura (ITP)?
• What are the symptoms and signs for idiopathic thrombocytopenic purpura (ITP)?
• How is idiopathic thrombocytopenic purpura diagnosed (ITP)?
• What are the treatments for idiopathic thrombocytopenic purpura (ITP)?
• How can idiopathic thrombocytopenic purpura be prevented (ITP)?
• Living with idiopathic thrombocytopenic purpura (ITP)
• What is the outlook for idiopathic thrombocytopenic purpura (ITP)?
• What are other names for idiopathic thrombocytopenic purpura (ITP)?
• Idiopathic Thrombocytopenic Purpura (ITP) At A Glance
• Patient Comments: Idiopathic Thrombocytopenic Purpura (ITP) - Symptoms
• Patient Comments: Idiopathic Thrombocytopenic Purpura - Treatments
• Find a local Doctor in your town
• Idiopathic Thrombocytopenic Purpura (ITP) Index

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.

Your doctor will diagnose idiopathic thrombocytopenic purpura (ITP) based on your medical history, a physical exam, and test results.

Your doctor will want to make sure that your low platelet count isn't due to another condition (such as an infection) or a side effect of medicines you're taking (such as chemotherapy medicines or aspirin).

Medical History

Your doctor may ask about:

• Your signs and symptoms of bleeding and any other signs or symptoms you're having
  
  
• Whether you have illnesses that could lower your platelet count or cause bleeding
  
  
• Medicines or any other over-the-counter supplements or remedies you take that could cause bleeding or lower your platelet count

Physical Exam

Your doctor will give you a physical exam and look for signs of bleeding and infection. For example, your doctor may look for pinpoint red spots on the skin and bruising or purplish areas on the skin or mucous membranes. These are signs of bleeding under the skin.

Diagnostic Tests

You'll likely have blood tests to check your platelets. These tests 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.

Some people who have mild ITP have few or no signs of bleeding. These people may be diagnosed only after a blood test done for another reason shows that they have a low platelet count.