Elevated von Willebrand factor antigen in systemic sclerosis: Relationship to visceral disease

Plasma levels of the factor VIII complex (von Willebrand factor antigen, factor VIII coagulant and ristocetin co-factor) were measured in 28 patients with systemic sclerosis. Elevated von Willebrand factor antigen was found in 12 patients overall and in 10 of 16 patients characterized by severe extensive visceral disease, with a resulting positive correlation between the extent of visceral involvement and the plasma level of von Willebrand factor antigen (r = 0.60, p <0.001). Factor VIII coagulant and ristocetin co-factor levels, however, frequently failed to parallel the increase of von Willebrand factor antigen, supporting the view that these increases were due to in vivo endothelial damage. The findings suggest that vascular damage is an impotant aspect of the visceral lesions of systemic sclerosis.