Clinical relevance of β₂-glycoprotein-I plasma levels in antiphospholipid syndrome (APS).

Antiphospholipid syndrome (APS) is characterized by the presence of antiphospholipid (aPL) antibodies associated with thrombosis or pregnancy morbidity. The antibodies mainly involved in this disorder are directed against β2-glycoprotein I (β2-GPI). β2-GPI plasma level is usually not reported in studies on APS, because it is not regarded as relevant to the diagnosis and prognosis of APS. Nevertheless its measurement may be important for understanding the pathophysiology of the syndrome. This review summarizes available data from the literature on plasma concentrations of β2-GPI in patients with different antibody profiles.