Idiopathic thrombocytopenic purpura with black oral mucosal lesions.

Idiopathic thrombocytopenic purpura (ITP) is an acquired autoimmune disorder in which autoantibodies are made against platelets, causing accelerated platelet destruction. History and physical examination are most often normal except for petechiae, commonly seen in the lower extremities. Hemorrhagic bullae of mucous membranes can indicate the presence of severe thrombocytopenia.