Acquired von Willebrand syndrome

Abstract

Acquired von Willebrand syndrome (AvWS) is a rare hemorrhagic diathesis with clinical symptoms similar to those associated with the inherited form of von Willebrand disease. This syndrome is characterized by the lack of previous bleeding symptoms, negative familial history, and occurrence in a relatively older age. Most commonly, AvWS develops in the course of other conditions such as lymphoproliferative, myeloproliferative, cardiovascular and autoimmune disorders; additionally it can be associated with some non-hematological malignancies and use of certain drugs. Pathogenesis of von Willebrand syndrome is complex and not fully understood. Deficiency or impaired activity of von Willebrand factor (vWF) can result from the presence of specific antibodies against this factor, its adsorption onto the surfaces of neoplastic cells, mechanic injury or proteolysis. Diagnosis is based on the measurements of plasma concentration and activity of vWF, and multimeric analysis. Management of AvWS includes the therapy of underlying disease and the control or prevention of bleeding. Hemostatic drugs that are most commonly prescribed in this syndrome include desmopressin, vWF concentrates, recombinant activated factor VII, intravenous immunoglobulin and adjunctive antifibrynolytic therapy. Additionally, plasmapheresis is required in some cases.
Hematologia 2011; 2, 4: 318–325