[Association of acquired Willebrand's disease, monoclonal gammopathy and angiodysplasia of the small bowel: a rare indication of high-dose intravenous immunoglobulins].

Acquired von Willebrand's disease associated with a monoclonal gammopathy and angiodysplasia of the gut is a rare disorder. It is sometimes complicated by chronic intestinal bleeding and severe anemia, that is poorly responsive to usual treatments. We report such a new case that has been revealed by anemia, and characterised by the absence of the high-molecular weight multimers. The correction of the hemostasis defect and of anemia were related to the reappearance of the high-molecular weight multimers, that was achieved only after high-dose intravenous immunoglobulin courses. The perfusions were performed every 3 weeks for 2 years without loss of efficiency, that could be explained by the dissociation of immunoglobulin-von Willebrand's factor complex.