Acquired von Willebrand Syndrome.

Acquired von Willebrand syndrome can occur in the setting of myeloproliferative neoplasms; plasma cell dyscrasias and other lymphoproliferative disorders; autoimmune conditions; and causes of increased shear forces, such as aortic stenosis or other structural heart disease and mechanical circulatory support. The depletion of von Willebrand factor, especially high-molecular-weight multimers, can lead to mucocutaneous bleeding and the formation of arteriovenous malformations, particularly in the gastrointestinal tract. Management focuses on correction of the underlying cause when possible, but may include intravenous immunoglobulins, von Willebrand factor concentrate, rituximab, or antiangiogenic therapy depending on the clinical context.