Thrombotic thrombocytopenic purpura (TTP) is a rare and potentially fatal thrombotic microangiopathy, defined by a mechanical hemolytic anemia, severe thrombocytopenia, and visceral ischemia due to systemic platelet-rich microthrombi. Mechanistically, TTP is most likely caused by an autoantibody-mediated deficiency of the von Willebrand Factor (vWF) cleaving protease ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif member 13) resulting in the accumulation of ultralarge vWF multimers, which further leads to microthrombi formation and end-organ ischemia.
