Chronic immune thrombocytopenia (also known as chronic immune thrombocytopenic purpura) is an immune disorder in which the immune system destroys platelets which are necessary for normal blood clotting. People with the disease do not have enough platelets in their blood.
Platelets are cells produced by the bone marrow and are normally found in the blood to help blood clot. When platelet counts are low, this can lead to bruising and bleeding more easily than usual. There are two main types of ITP acute (short term) and chronic (long term). Children may develop ITP after a viral infection and they usually recover fully without treatment. In adults, ITP is often chronic and it can occur after a viral infection, with the use of certain medications, during pregnancy, or as part of an immune disorder.