Mycology/Parasitology USMLE Step 1 Practice Question
A 3-year-old boy from West Africa presents with hepatosplenomegaly, jaundice, and severe anemia (hemoglobin 6.2 g/dL). Vital signs show temperature 38.9°C, heart rate 128/min, blood pressure 95/62 mmHg, and normal oxygen saturation. He reports recurrent malaria-like fevers over the past month but denies recent transfusions. Thick blood smear demonstrates crescent-shaped parasites with cytoplasm extending beyond the RBC membrane. Which organism is most likely responsible?
Answer choices
- APlasmodium falciparumCorrect answer
- BEntamoeba histolytica
- CTrypanosoma brucei
- DSchistosoma mansoni
- EPlasmodium vivax
- FPlasmodium malariae
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