Factor VIII: von Willebrand factor patterns in the plasma of patients with pre-eclampsia.

Elevation of the factor VIII protein to coagulant ratio previously has been reported to predict the severity of pre-eclampsia. Abnormal levels and patterns of factor VIII: von Willebrand factor (VIII/vWF) have been reported in thrombotic thrombocytopenia purpura (TTP). Severe pre-eclampsia shares many features with this syndrome. Nine primigravid patients with pre-eclampsia were evaluated by assays for factor VIII/vWF protein and coagulant activity and were compared to nine normal primigravid (controls). The patients and controls were indistinguishable by factor VIII antigen/coagulant activity ratios. Pre-eclamptic patients also had unremarkable factor VIII patterns on crossed immunoelectrophoresis. The evaluation of factor VIII/vWF multimeric patterns showed four patients with abnormal patterns in the pre-eclamptic patients and three abnormal patterns in the controls. These patterns were not analogous to the factor VIII abnormalities found in TTP.