Acquired von Willebrand's syndrome with a regressive evolution is described in a 66
year old man with Waldenström's disease. An inhibitor electively directed against
Ristocetin cofactor activity has been demonstrated, active in vitro after incubation
at 37° C. Serum fractionation showed that the inhibitor was independant of the monoclonal
IgM and subsequent purification that it was IgG in nature. The results permit its
classification as an auto-antibody.
Key words
Acquired von Willebrand's syndrome - Auto-antibody - Waldenström's disease