Mo Lan, Bao George C
Weill Cornell Medicine, New York-Presbyterian Lower Manhattan Hospital, 170 William Street, New York, NY 10038 USA.
Exp Hematol Oncol. 2017 Mar 24;6:8. doi: 10.1186/s40164-017-0068-3. eCollection 2017.
Acquired factor VIII (FVIII) deficiency, or acquired hemophilia A (AHA), is a rare autoimmune disorder involving antibody-mediated depletion of coagulation FVIII, leading to severe, life-threatening bleeding. The condition is often associated with other autoimmune disorders, and its treatment involves replacement of FVIII and various modes of immunosuppression. Recently, a few noteworthy therapeutic advances have been made. We present two cases of severe AHA in Chinese women. One of these women developed this disorder in the setting of possible parvovirus B19 infection, which has not yet been reported in association with AHA. Other notable features of her case included paradoxical venous thrombosis and possible association with Sjogren's syndrome and myositis. The other woman failed to respond to usual first-line therapies despite exhibiting a less severe clinical course, illustrating the varied but potentially stubborn behavior of this disorder.
CASE 1: An 87-year-old woman presented with diffuse ecchymoses, melena, vaginal bleeding. Labs showed hemoglobin (Hgb) nadir of 5.7 mg/dL, elevated partial thromboplastin time (PTT), FVIII level <1%, mixing study consistent with an inhibitor, elevated anti-Sjogren's-Syndrome-related antigen A antibody, elevated creatinine kinase, and elevated parvovirus IgM and IgG. Imaging of her arm showed diffuse myositis and deep venous thrombosis. After intravenous and oral steroids, her FVIII levels normalized, and her symptoms subsided.
CASE 2: A 59-year-old woman presented with recurrent ecchymoses and hematomas in her extremities. Labs showed Hgb of 11.7 mg/dL, elevated PTT, FVIII level of 3%, and mixing study consistent with an inhibitor. Despite receiving a long course of steroids, several courses of IVIG, and a few courses of Rituximab, her FVIII level remained critically low.
The rarity of AHA limits our understanding of this disease and the ability to perform trials to discover optimal therapies. We hope that these case reports and discussion will shed further light on the varied clinical manifestations and natural histories of this disorder to guide better recognition and treatment of AHA.
获得性因子 VIII（FVIII）缺乏症，即获得性血友病 A（AHA），是一种罕见的自身免疫性疾病，涉及抗体介导的凝血因子 FVIII 消耗，导致严重的、危及生命的出血。该疾病常与其他自身免疫性疾病相关，其治疗包括 FVIII 替代治疗和多种免疫抑制方式。最近，取得了一些值得注意的治疗进展。我们报告两例中国女性严重 AHA 病例。其中一名女性在可能感染细小病毒 B19 的情况下患上这种疾病，此前尚未有与 AHA 相关的报道。她的病例的其他显著特征包括矛盾性静脉血栓形成以及可能与干燥综合征和肌炎有关。另一名女性尽管临床病程较轻，但对常规一线治疗无反应，这说明该疾病表现多样但可能较为顽固。
病例 1：一名 87 岁女性出现弥漫性瘀斑、黑便、阴道出血。实验室检查显示血红蛋白（Hgb）最低点为 5.7mg/dL，部分凝血活酶时间（PTT）升高，FVIII 水平<1%，混合试验结果与存在抑制剂相符，抗干燥综合征相关抗原 A 抗体升高，肌酸激酶升高，细小病毒 IgM 和 IgG 升高。其手臂影像学检查显示弥漫性肌炎和深静脉血栓形成。经静脉和口服类固醇治疗后，她的 FVIII 水平恢复正常，症状消退。
病例 2：一名 59 岁女性出现四肢反复瘀斑和血肿。实验室检查显示 Hgb 为 11.7mg/dL，PTT 升高，FVIII 水平为 3%，混合试验结果与存在抑制剂相符。尽管接受了长时间的类固醇治疗、几个疗程的静脉注射免疫球蛋白（IVIG）以及几个疗程的利妥昔单抗治疗，她的 FVIII 水平仍极低。
AHA 的罕见性限制了我们对该疾病的了解以及进行试验以发现最佳治疗方法的能力。我们希望这些病例报告和讨论将进一步阐明该疾病多样的临床表现和自然病程，以指导更好地识别和治疗 AHA。
