Risk assessment in patients with antiphospholipid antibodies

Antiphospholipid syndrome (APS) is an autoimmune disorder characterized by the association of antiphospholipid antibodies (aPL) with thrombosis and/or pregnancy loss: classification criteria were defined in the updated international consensus held in Sidney in 2005. Vascular and obstetric manifestations display partially different pathogenetic mechanisms. Thrombosis develop as a result of local procoagulative changes upon triggers influence (second-hit theory). Pregnancy morbidity is thought to be dependent on placental thrombosis and complement activation. The laboratory tests include Lupus Anticoagulant (LA), a functional assay, and anticardiolipin (aCL) and anti-β2-glycoprotein I antibodies detected by solid phase enzyme-linked immunosorbent assay (ELISA). The LA testing is relatively standardized while there's still significant interlaboratory discrepancy in ELISA tests. Current APS criteria are under discussion: since for vascular and obstetric APS, different pathogenetic mechanisms have been shown, some criteria variation could also be contemplated. What is the weight of aPL antibodies in provoking thrombosis and which contribution could be expected from aPL per se is debated. As thrombosis is generally considered to be multi-factorial, each case needs a risk-stratified approach. Any primary prophylaxis, intensity and duration of secondary prophylaxis should take into account aPL profile, other cardiovascular risk factors and systemic autoimmune diseases associated. We look forward to the publication of recommendations of the leading experts in the field, developed during the recent 14th International Congress in Rio de Janeiro, Brazil.