A physician can look at the cells in the bone marrow and, in a child with ITP, would see many young platelets that have been produced. However, the blood test results of the circulating blood would show a very low number of platelets. The body is producing the cells normally, but the body is also destroying them. In most cases, other blood tests are normal except for the low number of platelets. ITP platelets usually survive only a few hours, in comparison to normal platelets which have a lifespan of 7 to 10 days.
Platelets are essential for the formation of a blood clot.
Blood clots consist of a mass of fibers and blood cells. Platelets travel to a damaged area and stick together to form a plug, whenever a person is cut, for example. If there are not enough platelets, a clot cannot be formed, resulting in more bleeding. Some medications may result in the altering of platelet function. Normal platelet count is in the range of 150,000 to 450,000.