ANTI-BETA-2GLYCOPROTEIN-1 ANTIBODIES IN I DIOPATHIC LIVEDO-RETICULARIS

Introduction. Idiopathic livedo reticularis can be a sign of systemic disease since certain complications are frequently associated: cerebra l thrombotic events in Sneddon's syndrome, necrotic ulcerations of the lower limbs. Antiphospholipid antibodies have been found in 0 to 85 p . 100 of patients with Sneddon's syndrome and anti-beta 2-glycoprotein 1 antibodies in 65 p. 100 of a series of 20 cases with Sneddon:s synd rome. The aim of our study was to determine the prevalence of anti-bet a 2-glycoprotein 1 antibodies in idiopathic livedo reticularis. Patien ts and methods. Twelve patients in a series of 17 with idiopathic live do reticularis seen between 1981 and 1992 were studied progressively. All underwent a clinical examination and simple laboratory tests with search for anticardiolipin antibodies, lupus type circulating anticoag ulant and anti-beta 2-glycoprotein 1 antibodies. Results. Eight of our 12 patients (60 p. 100) were positive for anti-beta 2-glycoprotein 1 antibodies, 3 of whom also had episodes of thrombosis similar to those described in antiphospholipid syndrome. Only one of the 8 patients al so had anticardiolipin antibodies and no chronic manifestation of thro mbosis. Discussion. beta 2-glycoprotein 1 is a cofactor which increase s anticardiolipin antibody adhesion to cardiolipin in ELISA. Anti-beta 2-glycoprotein 1 antibodies are associated with thrombosis and antiph ospholipid antibodies with lupus. Our results would suggest that the p revalence of anti-beta 2-glycoprotein 1 antibodies is high in idiopath ic livedo, bur, due to the small number of patients, do not allow conf irmation that anti-beta 2-glycoprotein 1 antibodies are associated wit h thrombosis. Anti-beta 2-glycoprotein 1 antibody assay would be justi fied in routine evaluation of patients with livedo and at follow-up ex aminations.