Mikhail Sameh, Aldin Ehab Saad, Streiff Michael, Zeidan Amer
Department of Hematology, Ohio State University Medical Center, Columbus, OH, USA.
Expert Rev Hematol. 2014 Apr;7(2):217-31. doi: 10.1586/17474086.2014.868771. Epub 2014 Feb 12.
Type 2B von Willebrand disease (VWD) accounts for fewer than 5% of all VWD patients. In this disease, mutations in the A1 domain result in increased von Willebrand factor (VWF) binding to platelet GPIbα receptors, causing increased platelet clearance and preferential loss of high molecular weight VWF multimers. Diagnosis is complicated because of significant clinical variations even among patients with identical mutations. Platelet transfusion often provides suboptimal results since transfused platelets may be aggregated by the patients' abnormal VWF. Desmopressin may cause a transient decrease in platelet count that could lead to an increased risk of bleeding. Replacement therapy with factor VIII/VWF concentrates is the most effective approach to prevention and treatment of bleeding in type 2B VWD.
2B型血管性血友病（VWD）在所有VWD患者中占比不到5%。在这种疾病中，A1结构域的突变导致血管性血友病因子（VWF）与血小板糖蛋白Ibα受体的结合增加，从而导致血小板清除增加以及高分子量VWF多聚体的优先丢失。由于即使是具有相同突变的患者之间也存在显著的临床差异，因此诊断较为复杂。血小板输注往往效果欠佳，因为输注的血小板可能会被患者异常的VWF聚集。去氨加压素可能会导致血小板计数短暂下降，进而增加出血风险。使用凝血因子VIII/VWF浓缩物进行替代治疗是预防和治疗2B型VWD出血的最有效方法。
