Takafuta T, Fujimura K, Shimomura T, Kawano H, Takimoto Y, Fujimoto T, Nagai N, Okamoto E, Ohama K, Nakamura K
Department of Internal Medicine, Hiroshima University, Japan.
Int J Hematol. 1994 Aug;60(2):163-72.
Type IIB is a rare variant of von Willebrand disease (vWD). An affected individual's bleeding tendency and thrombocytopenia are exacerbated with pregnancy, and the proper management of these patients during delivery has not been well established. Since it is important to distinguish this disease from the platelet type vWD in order to administer the appropriate therapy, gene analysis is necessary to make the precise diagnosis. We now report the successful management of delivery in three patients, who were diagnosed as having type IIB vWD by the detection of missense mutations in the von Willebrand factor (vWF) gene (C3916-->T and C3922-->T). These changes cause Arg543-->Trp and Arg545-->Cys substitutions in the A1 domain of vWF. We were able to manage the bleeding tendency of these patients at delivery mainly with vWF concentrates to supply normal vWF.
IIB型是血管性血友病（vWD）的一种罕见变异型。受影响个体的出血倾向和血小板减少症在妊娠期间会加重，而分娩期间对这些患者的妥善管理尚未明确确立。由于为了给予适当治疗而将这种疾病与血小板型vWD区分开来很重要，因此进行基因分析以做出准确诊断是必要的。我们现在报告3例患者分娩的成功管理情况，这些患者通过检测血管性血友病因子（vWF）基因中的错义突变（C3916→T和C3922→T）被诊断为患有IIB型vWD。这些变化导致vWF A1结构域中的精氨酸543→色氨酸和精氨酸545→半胱氨酸替换。我们主要通过使用vWF浓缩物来提供正常的vWF，从而在分娩时控制了这些患者的出血倾向。
