What are antiphospholipid antibodies? What is their clinical significance?
Antiphospholipid antobodies are antibodies directed against against epitopes on plasma proteins that are uncovered by the binding of these proteins to phospholipids.
The presence of these antibodies in high titers predisposes to venous and arterial thrombus formation, as well as spontaneous abortion. A patient with persistently elevated levels of these antibodies and associated clotting is considered to have the antiphospholipid antibody syndrome. This can occur as a primary phenomenon or secondary to systemic lupus.
Three different antiphospholipid antibodies can be measured clinically:
- anti-cardiolipin antibodies
- lupus anticoagulant