At least Type VWD2B is a discrete variant of VWD, isn't it?

摘要

Type 2B von Willebrand Disease (VWD2B) is generally characterized as including patients with bleeding symptoms whose laboratory studies demonstrate (1) reduced von Willebrand factor (VWF), (2) loss of high- molecular-weight VWF multimers, (3) thrombocytopenia, and (4) platelet aggregation of patient platelet-rich plasma to low concentrations of ristocetin (usually <= 0.6 mg/mL).~(1,2) The article by Federici et al is critical because it demonstrates the pheno-typic diversity of laboratory tests in patients diagnosed with VWD2B. While clinical laboratory studies using ristocetin have recognized laboratory to laboratory differences, this collaborative group includes laboratories of excellence that are recognized for their precision in VWD diagnosis