Von Willebrand disease (VWD) is caused by defective platelet adhesion, which results from defects in the von Willebrand factor (VWF) protein. Type 1 VWD is characterized by a bleeding disorder associated with a partial deficiency of VWF. This type accounts for 50-70% of VWD, being the most common type. The onset of bleeding varies; earlier onset is usually associated with severe VWF deficiency. The bleeding disorder associated with type I VWD is characterized by menorrhagia, epistaxis, or prolonged bleeding after trauma and/or a surgical intervention.
There are several treatment options for affected patients. Patients with type I VWD generally show a good response to desmopressin.
VWD is caused by mutations in the von Willebrand factor (VWF) gene. Mutations in this gene lead to intracellular retention or rapid clearance of VWF from the circulation. The level of VWF in blood group O is 25-35% lower than in non-O blood groups. Therefore, individuals with blood group O are at a greater risk for developing VWD.