Immune thrombocytopenia, or ITP, is an autoimmune blood disorder that results in a lower than normal level of blood platelets in the body. In people with ITP, antibodies malfunction and begin to attack blood platelets as if they were foreign invaders and less platelets are made to make up for those that are lost. Since blood platelets help stop bleeding by triggering the clotting process in the presence of a wound, a lower number of platelets increases the risk of bleeding. But as we'll see in this program, for many patients with ITP, medical science has made impressive strides in helping them maintain proper levels of platelets, reducing the risks that can come with serious bleeding.