[Reduction of Willebrand activity in patients with chronic kidney failure].

Decreased factor VIII von Willebrand activity in contrast with increased factor VIII procoagulant activity and increased concentrations of factor VIII related antigen, were found in the plasma of patients with chronic renal failure. This functional abnormality of the factor VIII protein is not improved by haemodialysis, but it is no longer found in patients with normally functioning grafted kidneys. It may at least partly explain the prolonged bleeding time commonly found in chronic renal failure.