Biochemistry, Lupus Anticoagulant

Excerpt

The term 'lupus anticoagulant' is a misnomer as it is neither only found in lupus, nor is it mainly associated with bleeding. The term LA was first coined to describe the phenomenon of plasma samples from patients with systemic lupus erythematosus (SLE) that failed to clot within an appropriate time. Lupus anticoagulant (LA) is one the of antiphospholipid antibodies, which also include anticardiolipin (aCL) antibody and anti-beta2-glycoprotein (GP) I antibodies. LA are heterogenous autoantibodies, predominantly IgG, and IgM isotypes that specifically target the phospholipid-protein component of the cell membrane. LA interferes and prolongs clotting process, which is a risk factor for arterial and/or venous thrombosis with complications such as stroke, transient ischemic strokes, acquired thrombophilia, and pregnancy loss. Furthermore, LAs may be transitory in the setting of certain medications or infections and thus have also present in asymptomatic patients. Testing for LAs is essential in patients with hypercoagulable states and antiphospholipid syndromes.