TTP occurs due to ADAMTS13 deficiency and typically provokes “microvascular thrombosis” in capillaries and arterioles of the kidneys and brain because microthrombi are formed in microcirculation [78, 79] and become trapped in the microvasculature in situ, promoting activation of “aberrant” ULVWF path of hemostasis without intravascular injury. Here, ADAMTS13 is linked to thrombotic thrombocytopenic purpura.