Immune thrombocytopenia (ITP) is a bleeding disorder that causes the blood not to clot properly. This is due to a low number of blood cell fragments called platelets that causes clotting.
People who have ITP often have purple bruises called purpura. These bruises appear on the skin or mucous membranes. People who have ITP also may have bleeding that causes tiny red or purple dots on the skin. People who have ITP also may have nosebleeds, bleeding from the gums during dental work, or other bleeding that's hard to stop. Women who have ITP may have menstrual bleeding that's heavier than normal.
In most cases, an autoimmune response is thought to cause ITP. Normally, your immune system helps your body fight off infections and diseases. But if you have ITP, your immune system attacks and destroys its own platelets. The reason why this happens isn't known.
Acute ITP generally lasts less than 6 months. It mainly occurs in children and is the most common type of ITP. Acute ITP often occurs after a viral infection. Chronic ITP lasts 6 months or longer and mostly affects adults.
For most children and adults, ITP isn't a serious or life-threatening condition.
Acute ITP in children often goes away on its own within a few weeks or months and doesn't return. In 80 percent of children who have ITP, the platelet count returns to normal within 6 to 12 months. Treatment may not be needed.
Chronic ITP varies from person to person and can last for many years. Even people who have severe forms of chronic ITP can live for decades. Most people who have chronic ITP can stop treatment at some point and maintain a safe platelet count.