A previously healthy 37–year–old male patient presented with 4 days of fever, nausea, myalgias and headaches. Patient had returned from a 3–week vacation trip to Malawi 2 weeks before this episode. He did take doxycycline as prophylaxis for few days at the beginning of his trip. Two days before the admission patient noticed dark urine and oliguria. In the ER patient was found to have a fever of 39°C, significant dehydration, tachycardia, diaphoresis and rigors. Physical exam revealed mild jaundice and abdominal left upper quadrant tenderness. His CBC showed leukocytes of 3.5K cells/mL (differential: 72% neuthophils, 17% lymphocytes and 4% bandemia), thrombocytopenia of 100K cells/Ul. Transaminases were elevated two times above baseline. Elevated bilirubins, elevated LDH and d–dimer and low haptoglobin confirmed active hemolysis and DIC. His peripheral smear (Figure 1) showed an impressive and worrisome high level parasitemia (25%) with ring forms (trophozoites), doublets and triplets red cell infestation forms, suspicious for Plasmodium falciparum. Patient was given a dose of atovaquone–proguanil while awaiting artesunate which was requested from the CDC. The drug arrived and was administered later that same day. The second day, patient persisted tachycardic and febrile and developed severe headaches and altered mental status. His platelet count went down to 35K cells/mL. CT scan of the head was unremarkable. He began to improve clinically on the third day with normalization of his heart rate, temperature and biochemical profile and decreased parasitemia. He completed 3 days of IV artesunate and was discharged on oral atovaquone–proguanil. One–week follow up showed significant clinical improvement.
P. falciparum has the highest rates of complications and mortality. Travelers to areas where malaria is endemic often contract the disease, mostly because of lack of compliance with preventive measures and have a high risk for progression to severe disease due to no previous exposure to malaria. Criteria for severe malaria include cerebral malaria, pulmonary edema, acute renal failure, severe anemia, > 5% parasitemia, severe acidosis and hypoglycemia. These manifestations portend a poor prognosis, could develop abruptly and progress to death in a short time. The WHO recommends intravenous (IV) artesunate as the treatment of choice for severe malaria in adults in areas of low transmission. Until 2007, appropriate therapy would have been IV quinidine. IV artesunate is now available. Since it has been shown to have superior efficacy and is likely to have fewer side effects than IV quinidine, it is now appropriate therapy as long as it can be acquired promptly.
This is a fascinating case of severe malaria falciparum with an extremely high parasitemia (25%) treated with Artesunate with a favorable outcome due to an adequate assessment and rapid administration of proper treatment.
Figure 1Peripheral smear at presentation showing the extremely high level of parasitemia (25%) and certain forms typical of P. falciparum: 1. Ring forms (trophozoites) with double chromatin; 2. Douplets; 3. Triplets; 4. Applique forms in the periphery of the RBC. No gametocytes are observed.