Presumed antiphospholipid syndrome and thrombotic thrombocytopenic purpura: An infrequent association.

Antiphospholipid syndrome (APS) is an autoimmune disease that demonstrates antiphospholipid antibodies that cause hypercoagulability and leads to venous and arterial thrombosis. Autoantibodies to a disintegrin-like and metalloprotease with thrombospondin type I motif, member 13 (ADAMTS 13) play a role in the microthrombosis of thrombotic thrombocytopenic purpura in APS patients.