Immune thrombocytopenia (ITP), also known as immune or idiopathic thrombocytopenic purpura, is a blood disorder in which the immune system destroys platelets. As a result, people with ITP develop low platelet counts. This can cause red or purple dots on the skin, called petechiae, and problems with easy bruising, nosebleeds, blood blisters in the mouth or internal bleeding.
Platelets are produced in the bone marrow, along with red blood cells and white blood cells. Once in the blood, platelets plug small holes in blood vessel walls, preventing or stopping bleeding. Generally, people have about 140,000 to 450,000 platelets per microliter of blood at any given time. In people with ITP, however, the immune system produces antibodies that bind to platelets. The antibody-coated platelets are then removed from the patient’s bloodstream by the spleen, an internal organ next to the stomach that is part of the lymphatic system. This causes the low platelet count.
Some cases of ITP are mild and do not cause a significantly low platelet count or bleeding. As the platelet count decreases further, the risk of bleeding increases. Platelet counts less than 10,000 raise the concern for spontaneous bleeding. However, each person experiences bleeding symptoms differently for a given platelet count level.
In the United States, an estimated 30,000 new cases of ITP are diagnosed each year. Approximately 70 percent of adults with ITP are women, and 70 percent of these women are under the age of 40 when diagnosed. ITP is more common in children than in adults, and boys and girls are equally affected.
Our Approach to Immune Thrombocytopenia
UCSF delivers compassionate, personalized care for immune thrombocytopenia (ITP). Treatment options include several types of medication that can restore platelets to adequate levels. Splenectomy, or surgical removal of the spleen, provides a permanent cure but leaves patients more susceptible to infections.
People with mild ITP generally need monitoring but no immediate treatment. Patients may have to make lifestyle changes, such as avoiding contact sports and certain medications that affect platelets, including aspirin and ibuprofen.
UCSF Health medical specialists have reviewed this information. It is for educational purposes only and is not intended to replace the advice of your doctor or other health care provider. We encourage you to discuss any questions or concerns you may have with your provider.