Fibrin configuration on glass led to decrease of neutrophil adherence in systemic lupus erythematosus.

Using a previously developed in vitro assay of glass adherence of neutrophils following blood clotting, we compared the results of new patients with systemic lupus erythematosus (SLE), juvenile rheumatoid arthritis (JRA) and those of normal controls. In acute phase of the disease, all 33 patients (100%) of SLE, 2 of 35 patients (5.7%) with JRA had a significantly low neutrophil adherence to glass surface (less than 25% of the normal values). During 2 years follow-up in 18 patients with SLE from the onset of the disease, we consistently observed the low cell adherence during the relapses of the disease in all the patients. When remains of glass surfaces were examined under scanning electron microscope (SEM), we found a notable morphologic difference of fibrin configuration between the specimens of active SLE and normal controls. We conclude that the varied results of neutrophil adherence on glass may reflect the forming of different fibrin configuration induced by the in vitro contact system of coagulation. The findings may explain the increased thrombotic complications reported in patients with active SLE.