Thrombotic thrombocytopenic purpura (TTP), which is hereditary (ADAMTS13 mutations) or acquired (antibodies against ADAMTS13), can present with a wide spectrum of manifestations including microangiopathic hemolytic anemia, thrombocytopenia, neurologic manifestations, gastrointestinal symptoms, purpura, and/or renal disease [9]. This evidence concerns the gene ADAMTS13 and congenital thrombotic thrombocytopenic purpura.