ABSTRACT
Systemic lupus erythematosus is the prototype of autoimmune disease. Since organ involvement in SLE is due to a vascular inflammatory process, many researchers try to find a marker of endothelial cell damage, which may indicate active vasculitis in SLE. Serum thrombomodulin [TM] is considered a marker of endothelial cell dysfunction. It is one of the soluble forms of tissue TM. A common mechanism for the increase of soluble TM may be an accelerated release of TM from injured endothelial cells. Measurement of the level of serum TM in systemic lupus erythematosus patients and to correlate it with the different clinical manifestations and laboratory parameters. This work was performed on 30 Egyptian SLE female patients and 10 .controls. Those patients were subjected to thorough clinical examination, laboratory tests including complete blood picture, ESR serum creatinine level, SCOT, SGPT, blood glucose level, serum C3, C4 level, ANA, anti-DNA, in addition to complete; urine analysis and estimation of the level of TM with ELISA. The level of serum TM differentiated lupus patients from controls. In addition it correlated strongly with disease activity score [as assessed with SLEDAI], with activity parameters and parameters of renal damage as serum creatinine level and proteinuria.[s]TM was higher among patients with pleurisy, pericarditis and thromboembolic manifestations and vasculitis, and this implies its valuable role in the immune pathogenesis of vasculitis in SLE. Results recommend measurement of serum TM in the assessment of SLE patients regarding activity and endothelial cell injury