Soluble thrombomodulin and antibodies to bovine glomerular endothelial cells in patients with Henoch-Schönlein purpura.

AIM To evaluate the clinical significance of soluble thrombomodulin and antiendothelial cell antibodies (AECA) in children with Henoch-Schönlein purpura. METHODS Binding of serum AECA to bovine glomerular endothelial cells was evaluated by enzyme linked immunosorbent assay, cytotoxicity against glomerular endothelial cells by spectrophotometric assay, and soluble thrombomodulin concentrations by sandwich enzyme immunoassay. RESULTS IgA AECA were detected in seven of 15 patients with Henoch-Schönlein purpura and nephritis, but were not detected in patients without nephritis or in controls. Patients with Henoch-Schönlein nephritis had raised titres of IgA AECA and serum thrombomodulin; severe proteinuria and renal histological changes were associated with raised titres of IgA AECA and raised serum thrombomodulin. No subjects had complement dependent cytotoxicity against glomerular endothelial cells. CONCLUSIONS High titres of IgA AECA and raised serum thrombomodulin may be clinically useful markers of renal involvement in patients with Henoch-Schönlein purpura.