Studies of fibrin formation and fibrinolytic function in patients with the antiphospholipid syndrome.

Abstract Objective The antiphospholipid syndrome (APS) is defined by persistent antiphospholipid antibodies together with thrombosis and/or pregnancy morbidity. We investigated the tightness of fibrin clot and fibrinolytic function in plasma samples from APS patients compared with two control groups. Material and Methods APS patients (n = 49), healthy controls (HC) (n = 19) and warfarin-treated nonAPS thrombosis controls (nonAPS-TC) (n = 39) were investigated. Fibrin permeability was assessed as the permeability coefficient (Ks) by a flow measurement technique. Additionally, clot density and fibrinolytic function was analysed by a turbidimetric clotting and lysis assay. Fibrin structure was visualised using scanning electron microscopy. Finally, the number of cell-derived microparticles (MPs) in the samples were correlated to fibrin permeability Results and Conclusions The Ks value was lower in samples from APS-patients compared to HC and nonAPS-TC (p