VWF and hyperinsulinemic hypoglycemia, familial, 4: It is most likely due to a heterogenous group of different underlying defects (e.g., low vWF, coagulation factor deficiencies, hyperfibrinolysis etc.)causing bleeding symptoms, or a collection of disorders that are yet to be identified.4,5 Up to 40% of BDUC patients have a family history of bleeding.5