Since >90–95% of patients with TTP are diagnosed with iTTP, many physicians may assume that the following points are true for “all” TTP patients: (i) severe thrombocytopenia, hemolytic anemia, and ischemic organ damage occur when ADAMTS13 levels fall <10%; (ii) without suitable therapeutic interventions, >90% of cases lead to a fatal outcome; (iii) all acute and recurrent cases must be treated in the hospital, sometimes in an intensive care unit; and (iv) treatment options are expanding and there are relatively well-established treatment protocols. This evidence concerns the gene ADAMTS13 and Thrombocytopenia.