May also be called: ITP; Immune Thrombocytopenic Purpura; Autoimmune Thrombocytopenic Purpura Idiopathic thrombocytopenic purpura (throm-bo-sy-tuh-PEE-nik PURR-puh-ruh), or ITP, is a bleeding disorder in which the blood has an abnormally low amount of a type of blood cell called platelets. More to Know There are three kinds of blood cells: red blood cells, white blood cells, and platelets. Platelets help the body form clots — thick clumps of blood that seal leaks, wounds, cuts, and scratches and prevent excessive bleeding. When a blood vessel breaks, platelets gather in the area and help seal off the leak. With ITP, the body's immune system produces antibodies (a type of protein) that attach to platelets and lead to their destruction. Having too few platelets can cause easy bruising (purpura), bleeding in the nose or mouth, blood in the urine, heavy menstruation, and a skin rash that looks like tiny red spots. Severe cases can cause internal bleeding and bleeding in the brain. Doctors aren't sure what causes ITP, but it usually happens after a viral infection, such as mumps or the flu, during pregnancy, or as part of an immune disorder like lupus or HIV. In many cases, ITP doesn't require treatment. More serious cases are treated with medications, a platelet transfusion if there is severe bleeding or, rarely, surgery to remove the spleen (a splenectomy). Keep in Mind In more than 80% of cases involving kids, ITP goes away on its own without treatment, usually within 6 months. Adults are more likely to need treatment, typically with steroid medications or splenectomy. In most cases, treatment for ITP is successful and the condition causes no long-term problems. All A to Z dictionary entries are regularly reviewed by KidsHealth medical experts. Back to Articles Related Articles Word! Platelets Your blood contains many tiny cells called platelets. Read More Henoch-Schönlein Purpura (HSP) Most kids who develop this inflammation of the blood vessels (marked by a raised red and purple rash) make a full recovery and have no long-term problems. Read More Blood Test: Complete Blood Count This common blood test helps doctors gather information about a person's blood cells and how they're working. Find out why doctors do this test and what's involved for teens. Read More Blood Find out about the mysterious, life-sustaining fluid called blood. Read More Spleen and Lymphatic System The lymphatic system is an extensive drainage network that helps keep bodily fluid levels in balance and defends the body against infections. Read More Blood Here are the basics about the life-sustaining fluid called blood. Read More The Lymphatic System The lymphatic system is an extensive drainage network that helps keep body fluid levels in balance and defends the body against infections. Read More Basic Blood Chemistry Tests Doctors order basic blood chemistry tests to assess a wide range of conditions and the function of organs. Read More What's Blood? It swirls through your veins and arteries, but what is it really? Find out about blood in this article for kids. Read More Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor. © 1995-2021 KidsHealth®. All rights reserved. Images provided by The Nemours Foundation, iStock, Getty Images, Veer, Shutterstock, and Clipart.com.