患儿男,69天。因“全身散在瘀点、瘀斑5天”入院。5天前,患儿无明显诱因出现全身散在瘀点、瘀斑,在当地医院查血常规:白细胞计数4.7×109/L,中性粒细胞58%,淋巴细胞42%,血红蛋白134g/L,血小板计数86×109/L,当地医院诊断为“血小板减少性紫癜”,静脉滴注地塞米松、维生素K1及止 Children male, 69 days. Because of “systemic scattered petechiae, ecchymosis 5 days” admission. Five days ago, there was no obvious incentive in children with systemic scattered petechia and ecchymosis. The routine blood tests were performed in local hospitals: white blood cell count 4.7 × 109 / L, neutrophil 58%, lymphocyte 42%, hemoglobin 134g / L, Platelet count 86 × 109 / L, the local hospital diagnosed as “thrombocytopenic purpura”, intravenous dexamethasone, vitamin K1 and only