Idiopathic TTP is an autoimmune disease caused by severe deficiency of the von Willebrand factor (VWF) cleaving protease, a disintegrin-like and metalloprotease with thrombospondin type 1 repeats (ADAMTS13), due to inhibitory anti-ADAMTS13 antibodies [4,5]. This evidence concerns the gene VWF and thrombotic thrombocytopenic purpura.