familial thrombotic thrombocytopenic purpura

Familial thrombotic thrombocytopenic purpura (TTP) is a rare disorder of abnormal blood coagulation. It is associated with mutations affecting the enzyme ADAMTS13, which normally regulates von Willebrand factor (vWF).1

vWF is a glycoprotein crucial for hemostasis, helping platelets adhere to each other and to damaged blood vessels to form clots and stop bleeding. ADAMTS13 regulates vWF by cutting it into smaller fragments. When ADAMTS13 is affected by mutations, vWF remains in an active, unfolded form, leading to excessive platelet activation and aggregation, and thus abnormal clotting. This contrasts with von Willebrand disease, which is caused by mutations in the VWF gene and results in reduced clot formation and prolonged bleeding. Thrombocytopathy refers to blood disorders with dysfunctional platelets, leading to bleeding.12