A 6-year-old boy is brought in due to pallor and decreased energy. For the past 2 days, he has slept throughout the day. The patient developed fever, emesis, and diarrhea 10 days ago, but symptoms resolved after a few days without intervention. Temperature is 37.1 C (98.8 F), blood pressure is 120/70 mm Hg, and pulse is 145/min. The patient appears tired and has pale lips. The abdomen is soft and nontender. There are a few small bruises along the bilateral shins. Laboratory results are as follows:
一个 6 岁的男孩因面色苍白和精力下降被带来就诊。在过去的 2 天里，他整天都在睡觉。患者在 10 天前出现发热、呕吐和腹泻，但症状在几天后自行缓解，没有进行干预。体温为 37.1°C（98.8°F），血压为 120/70 mm Hg，脉搏为 145 次/分钟。患者看起来很疲惫，嘴唇苍白。腹部柔软且无压痛。双侧小腿有几处小淤伤。实验室结果如下：
| Complete blood count 全血细胞计数 | |
| Hemoglobin 血红蛋白 | 6.4 g/dL (64 g/L) |
| Platelets 血小板 | 30,000/mm3 (30 × 109/L) 30,000/mm3 (30 × 10^9/L) |
| Leukocytes 白细胞 | 15,200/mm3 (15.2 × 109/L) 15,200/mm3 (15.2 × 10^9/L) |
| Serum chemistry 血清化学 | |
| Creatinine 肌酐 | 2.4 mg/dL (212.2 μmol/L) |
| Liver function studies 肝功能研究 | |
| Total bilirubin 总胆红素 | 3.3 mg/dL (56.4 μmol/L) |
| Direct bilirubin 直接胆红素 | 0.1 mg/dL (1.71 μmol/L) |
| Coagulation studies 凝血研究 | |
| PT | 12 sec 12 秒 |
| Activated PTT 活化部分凝血酶时间 | 35 sec 35 秒 |
Urinalysis has 20-30 red blood cells/hpf. Which of the following is the most likely diagnosis?
尿液分析显示每高倍视野有 20-30 个红细胞。以下哪项最可能是诊断结果？
A. | Autoimmune hemolytic anemia |