Case Presentation from our ED 本急诊科病例
20 y/o presents 3 weeks after emigrating from Senegal with headache and malaise. CT/LP and work up was otherwise negative. Thin smear shows 1 plasmodium falciparum parasite in 7000 RBC.
20岁的病人，从塞内加尔到美国3个星期，因头痛和乏力就诊。所有的检查，包括CT和腰穿都无异常。薄片检查发现在7000红血球中有一个恶性疟原虫。
Appropriate therapy is initiated with malarone (atovoquone and progranuil). 24 hours later the patient represents with worsening headache and fever.
病人及时接受了针对性药物治疗，malarone (阿托喹酮和氯胍)。24小时后，病人头痛和发烧症状加重。
Repeat smear shows 10% parasitemia and massive numbers of parasites
重复薄片检查发现10％寄生虫血症和大量寄生虫。
Clinical Question: Can parasitemia rise after initiation of treatment?
问题：治疗开始后会出现寄生虫血症吗？
Answer: Yes
答案：会的
Increase in blood parasite count in falciparum malaria after initiation of treatment (artemisinin derivatives or quinine) is not uncommon.
恶性疟原虫病在治疗(青蒿素衍生物或奎宁)开始后血中疟原虫数量增加现象不是不常见的。
Increased blood parasite count does not indicated treatment failure if it the parasitemia is LESS THAN 2.5 x the baseline count.
如果寄生虫血症不超过基础水平的2.5倍，并不代表治疗失败。
Clinical Question: Did this patient have treatment failure with malarone?
问题：这个病人用malarone治疗是失败了吗？
Answer: Yes
答案：是的
The patient’s parasitemia rose to 10% after initiation of therapy.
因为病人的寄生虫血症在治疗开始后达到了10％
There are increasing case reports of treatment failure in West Africa with Malarone.
在西非，用malarone治疗失败的病例有增加的趋势。

Bottom Line: A mild increase in blood parasite count after initiation of treatment is not uncommon. Marked increases should indicated treatment failure and the treatment drug should be changed to another class.
要点：治疗后小量的血液寄生虫出现并不罕见。大幅度的增加意味着治疗的失败。应考虑换其他类的药。

University of Maryland Section for Global Emergency Health
马里兰大学国际急诊健康部
Author 作者: Emilie J.B. Calvello, MD, MPH

References参考文献：
Wurts, N. Et al. Early treatment failure during treatment of Plasmodium falciparum malaria with atovaquone-proquanil in the Repulic of Ivory Coast. Malar J 2012 May; 2(11): 146.

Silachomroon, U. Et al. Frequency of Early Rising Parasitemia in Falciparum Malaria Treated with Artemisinin Derivatives. Southeast Asian J Trop Med Pub Health 2001 Mar; 32(1): 50 – 56.