Abt Nicholas B, Streiff Michael B, Gocke Christian B, Kickler Thomas S, Lanzkron Sophie M
Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
Division of Hematology, Department of Medicine, The Johns Hopkins Hospital, 1830 E. Monument Street, Suite 7300, Baltimore, MD 21205, USA.
Case Rep Hematol. 2014;2014:484563. doi: 10.1155/2014/484563. Epub 2014 May 14.
Objective. We present the case of a 73-year-old female, with no family or personal history of a bleeding disorder, who had a classic presentation for acquired hemophilia A. Factor VIII activity was low but detectable and a factor VIII inhibitor was undetectable. Methods. The patient's plasma was comprehensively studied to determine the cause of the acquired coagulopathy. Using the Nijmegen modification of the Bethesda assay, no factor VIII autoantibody was measureable despite varying the incubation time from 1 to 3 hours. Results. The aPTT was prolonged at 46.8 seconds, which did not correct in the 4 : 1 mix but did with 1 : 1 mix. Using a one stage factor VIII activity assay, the FVIII activity was 16% and chromogenic FVIII activity was also 16%. The patient was treated with recombinant FVII and transfusion, significantly reducing bleeding. Long-term therapy was initiated with cyclophosphamide and prednisone with normalization of FVIII activity. Conclusions. Physicians can be presented with the challenging clinical picture of an acquired factor VIII inhibitor without a detectable inhibitor by the Bethesda assay. Standard therapy for an acquired hemophilia A should be considered.
目的。我们报告一例73岁女性病例，其无出血性疾病家族史或个人史，呈现出获得性血友病A的典型表现。凝血因子VIII活性低但可检测到，且未检测到凝血因子VIII抑制剂。方法。对患者血浆进行全面研究以确定获得性凝血病的病因。使用尼美根改良的贝塞斯达试验，尽管将孵育时间从1小时延长至3小时，仍未检测到凝血因子VIII自身抗体。结果。活化部分凝血活酶时间（aPTT）延长至46.8秒，在4∶1混合试验中未纠正，但在1∶1混合试验中纠正。使用一步法凝血因子VIII活性测定，凝血因子VIII活性为16%，发色底物法测定的凝血因子VIII活性也为16%。患者接受重组凝血因子VII治疗及输血，出血明显减少。开始使用环磷酰胺和泼尼松进行长期治疗，凝血因子VIII活性恢复正常。结论。医师可能会遇到贝塞斯达试验检测不到抑制剂的获得性凝血因子VIII抑制剂的具有挑战性的临床情况。应考虑采用获得性血友病A的标准治疗方法。
