The clinical significance of coagulation abnormalities in systemic sclerosis (scleroderma)

A coagulation screen and measurement of circulating factor VIII related antigen (VIII-RAg), factor VIII coagulant activity (VIII-C) and β-thromboglobulin (βTG) levels were carried out in 25 patients with systemic sclerosis and 25 age and sex matched controls. Both VIII-RAg and βTG levels were significantly higher in the systemic sclerosis patients than controls. Fibrin degradation products were increased in 11 (44%) of the patients. There was a significant correlation between the VIII RAg/VIII-C ratio and severity of the vascular abnormalities noted on nailfold capillary microscopy. Those with VIII-RAg levels in excess of 200% of controls (10 of 25) had more severe disease with greater mean number of organ systems involved.