ABSTRACT
In order to clarify the association between antibodies to phospholipidbinding plasma protein particularly; B2-glycoprotein I, protein C and protein S and thrombotic complications in systemic lupus erythematosus patients [SLE], 42 patients with SLE were selected and 10 healthy subjects were also included as a control group, their age and sex matched with our patients. The Anti phospholipid antibodies [APL Abs] were measured by an Enzyme Linked Immunosorbant Assay [ELISA] system. The thrombotic events were determined by venography, arteriography, dopler ultrasound, computed tomography [CT] and magnetic resonant image [MIR]. Our result showed that all types of IgG APL Abs were detected in SLE patients [30% for anti-B2-Glycoprotein I, 21% for anti-protein C and 28% for anti-protein S], thrombotic events were detected in 12 of SLE patients [7 arterial and 5 venous]. The prevalence of LA and aCL were significantly higher in SLE patients with thrombosis than in those without thrombosis [P < 0.01], but there was non significant change between the prevalence of LA and aCL in patients with arterial and venous thrombosis [P> 0.05]. Concentration and prevalence of anti-B2-GPI was significantly higher in patients with arterial thrombosis than in those with venous thrombosis [P< 0.01]. The concentration and prevalence of anti-protein C and anti-protein S Abs were significantly higher in patients with venous thrombosis than in those with arterial thrombosis [P < 0.01]. There was non significant change in disease activity score between SLE patients with and without thrombotic events. There was significant correlation between the concentration of anti-B2-GPI Abs and aCL [r = 6.86, P < 0.01] and significant correlation between the concentration of Anti-protein C and Anti-protein S Abs [r = 0.66, P < 0.01]. We concluded that, anti-B2-GPI Abs, anti-protein C and anti-protein S Abs may play a differential role in thrombotic complications where anti-B2-GPI Abs may be associated primarily with arterial thrombosis and anti-protein C and/or anti-protein S Abs may be associated primarily with venous thrombosis