What is Lupus Anticoagulant?
Lupus anticoagulant comprises immunoglobulins that bind phospholipid-dependent coagulation reactions in vitro, paradoxically prolonging clotting times in laboratory tests whilst promoting thrombosis in vivo. Despite its name, lupus anticoagulant is neither specific to systemic lupus erythematosus nor an anticoagulant clinically. Detection relies on functional clotting assays — dilute Russell viper venom time or activated partial thromboplastin time — that demonstrate prolongation not corrected by mixing with normal plasma but corrected or attenuated by excess phospholipid, a pattern that distinguishes antibody from factor deficiency.