以發燒表現，合併急性心肌梗塞的血栓性血小板減少性紫斑

A Case of Thrombotic Thrombocytopenic Purpura Presented as Fever, Complicated with Myocardial Infarction

血栓性血小板減少性紫斑(TTP)是一種罕見的凝血功能障礙性疾病，其特徵是微血管性 溶血性貧血(MAHA)，血小板低下，及血栓導致的多種器官缺血性表現。根據研究，23% 的TTP的患者可能在早期出現類似上呼吸道感染的發燒和畏寒。常規檢察包括全血球計數 (CBC)，白血球分類計數(DC)和尿液分析。最先表現為貧血，血小板減少，受到破壞的紅 血球和輕度血尿。患者可能同時出現意識狀態改變和臨床的神經系統徵兆。在結合所提出 的臨床特徵討論的情況下，TTP應列為首先考慮的診斷之一。必須強調的是，TTP的延遲或 誤診有可能導致包含心臟在內的多器官衰竭，造成高死亡率。一旦診斷完成，應儘早開始 血漿置換和免疫抑制治療。對於所有TTP的病人，我們建議常規檢測心肌酵素，以期提早 發現心臟缺血的狀況。我們提出一個呈現典型TTP病徵且合併急性心肌梗塞的案例。

 

Thrombotic thrombocytopenic purpura (TTP) is a rare disease of coagulation dysfunction and is diagnosed in characters including of microangiopathic hemolytic anemia (MAHA), fragmented RBC, thrombocytopenia, thrombosis-mediated ischemic changes of various organs, such as the central nervous system and kidney, and fever. It was reported that MAHA and thrombocytopenia were seen in all patients (100%) diagnosed as TTP, 80% of patients presented neurological deficiencies, and 53% of patients had renal function impairments, while fever affected 10% of patients in early clinical stage. Patients are diagnosed as TTP by confirming of MAHA and thrombocytopenia, and aided by the minor three clinical criteria. The patients having all the five clinical diagnostic criteria were only 8.2%. Since patients who suffer from TTP in the early stage may only have fever presented in clinical picture, it is easily to be misdiagnosed in primary care. Investigation includes the CBC, DC, peripheral blood smear, creatinine, LDH, coagulation testing, urinalysis, ADAMTS13 (A disintegrin and metalloproteinase with thrombospondin motifs 13) activity and inhibitor testing. Initial Laboratory manifestation showed anemia, thrombocytopenia, fragmented RBC with poikilocytosis or anisocytosis, while urinalysis revealed mild haematuria. The patient may have concurrent consciousness changes and clinical neurologic findings. The presumptive diagnosis can be made upon MAHA combining unexplained thrombocytopenia, and can be confirmed by ADAMTS13 deficiency (<10% of normal). It should be highlighted that delayed or misdiagnosis of TTP may result in high mortality and morbidity due to multiorgan failure including heart. Plasma exchange and immunosuppressive therapy should be initiated as early as possible once the diagnosis has been made. It was suggested that cardiac enzymes should be screened for TTP patient in order to detect cardiac ischemia in early stage. We reported a 34-year-old man of TTP complicated with acute myocardial infarction during hospitalization.