男,12岁,因发热、咳嗽20天,进行性面黄、气促3天,便血1天入院。患儿20天前无诱因开始发热,体温38～39℃,伴单声咳嗽少量粘痰,无痰中带血,无胸痛。外院胸透:两肺纹理增强,点片状阴影。血常规白细胞2.6×10~9/L,中性0.73,淋巴0.37,红细胞4.35×10~(12)/L,血红蛋白131g/L,血小板55×10~9/L。按肺炎给青霉素、头孢噻肟治疗半月,病情渐加重,进行性面黄、气促,近3天体温升至40℃,入院当天黑便2次,鲜血便1次,量约250ml。以往否 Male, 12 years old, suffered from fever and cough for 20 days. He developed yellow face and shortness of breath for 3 days. He was admitted to the hospital for 1 day. 20 days before the child had no incentive to start fever, body temperature 38 ~ 39 °C, with a single cough a small amount of sticky sputum, no sputum with blood, no chest pain. Outside the chest: two lungs texture enhancement, point-like shadow. Blood white blood cells were 2.6×10 9/L, neutral 0.73, lymphoid 0.37, red blood cells 4.35×10 12/L, hemoglobin 131 g/L, platelets 55×10 9/L. According to pneumonia, penicillin and cefotaxime were treated for half a month. The condition was gradually worsened, and sexual yellowness and shortness of breath were raised. The body temperature rose to 40° C. in the past 3 days. Black stools were taken 2 times on the day of admission. The blood was once and the volume was about 250 ml. In the past