PDF(Pubmed)
Abstract：
Thrombocytopenia with concomitant anemia is a serious condition with a high mortality risk. Destruction of platelets, i.e., thrombocytopenia, can be secondary to either auto-antibodies (immune-mediated) or mechanical destruction (non-immune-mediated). The Coombs test is a widespread tool to differentiate between the two categories, resulting in different specific treatment approaches for each diagnosis. A peripheral blood smear can also help make the diagnosis; for instance, in cases of mechanical destruction such as thrombotic thrombocytopenic purpura (TTP), the red blood cell (RBC) shape looks fragmented, forming schistocytes. In rare instances, TTP can present with both schistocytes and a positive Coombs test, challenging the diagnosis of TTP. TTP is a hematological emergency requiring appropriate anticipation and the initiation of treatment prior to the confirmatory ADAMTS-13 test results. Mild forms of TTP can be managed with glucocorticoids and therapeutic plasma exchange. Refractory cases need more aggressive additional treatment with caplacizumab and rituximab. Caplacizumab is an expensive medication that is usually reserved for use after confirmation of a TTP diagnosis. The advantage of caplacizumab lies in its targeted mechanism of action against the A1 domain of the von Willebrand multimers that are normally destructed by the ADAMTS-13 enzyme. Here, we present a young female patient with confirmed TTP, and the initial diagnosis was challenged by the presence of antibodies with the Coombs test. Very little research has studied this rare instance and the appropriate treatment. Our case will save many future lives, as clinicians should be more aggressive in treating refractory TTP with a positive Coombs test.
摘要：
合并贫血的血小板减少是一种严重的疾病，具有很高的死亡风险。血小板的破坏,即，血小板减少症,可以继发于自身抗体(免疫介导的)或机械破坏(非免疫介导的)。Coombs测试是区分这两个类别的广泛工具，导致每种诊断的具体治疗方法不同。外周血涂片也可以帮助诊断;例如，在机械性破坏如血栓性血小板减少性紫癜（TTP）的情况下，红细胞（RBC）的形状看起来支离破碎，形成分裂细胞。在极少数情况下,TTP可以同时出现分裂细胞和Coombs试验阳性，挑战TTP的诊断。TTP是一种血液紧急情况，需要在确认的ADAMTS-13测试结果之前进行适当的预测和开始治疗。轻度形式的TTP可以用糖皮质激素和治疗性血浆置换来管理。难治性病例需要使用卡普拉斯单抗和利妥昔单抗进行更积极的额外治疗。卡普拉斯单抗是一种昂贵的药物，通常在确认TTP诊断后保留使用。卡普拉斯单抗的优势在于其针对vonWillebrand多聚体的A1结构域的靶向作用机制，该多聚体通常被ADAMTS-13酶破坏。这里,我们介绍了一名确诊TTP的年轻女性患者，最初的诊断受到Coombs试验抗体存在的挑战。很少有研究研究这种罕见的情况和适当的治疗方法。我们的案子将挽救许多未来的生命，因为临床医生应该更积极地治疗Coombs试验阳性的难治性TTP。
