VWF and platelet-type von Willebrand disease: von Willebrand disease (VWD) is the most common (autosomally) inherited bleeding disorder characterized by mucocutaneous bleeding, prolonged bleeding after trauma and surgery, epistaxis, and menorrhagia.1It is caused by genetic defects in the von Willebrand factor (VWF) gene resulting in either a quantitative deficiency (type 1 and 3) or dysfunction (type 2) of VWF.