Summary
The disappearance of plasma prothrombin was measured during the spontaneous clotting
of whole blood from 15 normal adults, from patients lacking fibrinogen, factor V,
VII, VIII, IX, X, XI, XII, or XIII, or Fletcher factor, from patients with von Willebrand’s
disease or Glanzmann’s thrombasthenia, and from one patient with an unidentified prothromboplastic
abnormality. Prothrombin utilization was normal in patients lacking fibrinogen or
factor VII or XIII or who had Glanzmann’s thrombasthenia. Utilization was most abnormal
in patients with the greatest deficiencies of factors V, VIII, IX, or XI. Patients
lacking factor XII or Fletcher factor consumed prothrombin rapidly after an abnormal
initial lag period. Within each group of patients with hemophilia A or von Willebrand’s
disease, the lower the concentration of factor VIII the more slowly was prothrombin
utilized, but with von Willebrand’s disease there was much more rapid prothrombin
utilization than with hemophilia with higher levels of factor VIII. Patients with
the most pronounced deficiencies of factor XI, factor XII, or Fletcher factor had
abnormal platelet adhesiveness.