Lupus anticoagulants (LA) are heterogeneous autoantibodies of the IgG and IgM type directly directed against a variety of anionic phospholipids such as cardiolipin, phosphatidylserine or phosphatidylinositol or against proteins having the capacity to bind to phospholipids such as β2-glycoprotein I (β2-GPI).

The presence of LA is primarily detected using sensitive in vitro tests using phospholipids, such as TCA (Activated Partial Time) or dRVVT. They have the in vitro capacity to prolong phospholipid-dependent clotting times but are most often associated with thrombotic complications in vivo (venous or arterial thrombosis, thrombocytopenia and fetal loss) and do not predispose to a risk of bleeding. DRVVT is routinely used in screening for LA. It is considered specific and robust.