ANTIPHOSPHOLIPID ANTIBODIES AND THROMBOTIC RISK - RELATIONSHIP TO THROMBOMODULIN, D-DIMERS AND PROTHROMBIN FRAGMENT-1+2

Antiphospholipid antibodies (aPLA) are frequently reported in associat ion with thrombosis. In order to investigate the possible pathogenic r ole of aPLA, we studied plasma levels of thrombomodulin (a marker of e ndothelial damage) and of prothrombin fragment F1+2 and D-Dimers (resp ectively direct and indirect markers of haemostatic activation) in 53 patients presenting lupus anticoagulants and/or anticardiolipin antibo dies, with or without systemic lupus erythematosus (SLE) and/or thromb otic manifestations. Results were compared to those obtained in 40 hea lthy subjects, 11 SLE patients and 25 patients presenting thrombosis i n the absence of aPLA. F1+2 levels were not significantly increased in any group of aPLA patients, while a significant increase in D-Dimers in the aPLA group could not be specifically related to the presence of aPLA. Conversely, thrombomodulin was significant increased in all aPL A groups relative to controls or patients without aPLA, which confirms the pathogenic influence of aPLA on vascular endothelium and suggests this could be one of the contributing factors in the development of p rothrombotic states.