[Diagnosis and treatment of von Willebrand disease]

von Willebrand disease (VWD) is a hereditary bleeding disorder resulting in quantitative and qualitative abnormalities of von Willebrand factor (VWF). VWD is classified into three types according to these abnormalities: type 1, quantitatively reduced; type 2, qualitatively abnormal (with four subtypes: 2A, 2B, 2M, and 2N); and type 3, completely deficient VWF. This classification is important for understanding the pathology and selecting treatment methods, but accurate and rapid diagnosis and classification of VWD is still very challenging. Recently, patients with clear bleeding tendency and VWF levels reduced to 30-50% have been defined as having low VWF, and preventing bleeding and performing hemostatic treatment as necessary is recommended. In this article, I refer to the Guidelines for the Diagnosis and Management of VWD jointly published in 2021 by the American Society of Hematology, the International Society on Thrombosis and Haemostasis, the National Hemophilia Foundation, and the World Federation of Hemophilia and the 2021 edition of the VWD Clinical Guidelines formulated by the Japanese Society on Thrombosis and Haemostasis to outline future directions and challenges regarding the concept of low VWF levels, diagnosis and hemostatic treatment of VWD, and bleeding prevention, taking into account recent evidence and topics of discussion.