[Willebrand's disease and multimeric analysis of the Willebrand factor].

The multimeric composition of von Willebrand factor (vWF) in the plasma of 20 von Willebrand's disease patients was analyzed to determine the type of von Willebrand's disease and to evaluate retrospectively the predictive value of the classical tests. Analysis of the multimeric pattern revealed that 3 had type II and the other 17 type I von Willebrand's disease. The classical tests, especially crossed immunoelectrophoresis of vWF and the ristocetin-induced platelet agglutination test, did not permit correct classification but led to overestimation of the type II von Willebrand variant. Multimeric analysis of von Willebrand factor is necessary to diagnose von Willebrand's disease type II, in which DDAVP infusions should not be given since they are ineffective or may cause thrombocytopenia.