Fungal and Parasitic Infections USMLE Step 1 Practice Question
A 6-year-old girl from sub-Saharan Africa presents with her mother reporting a 3-week history of chronic diarrhea, abdominal pain, and progressive abdominal distension. The mother notes the child has been playing barefoot in contaminated water sources near their village. On examination, vital signs are: heart rate 102/min, blood pressure 95/60 mmHg, temperature 37.2°C, respiratory rate 20/min. Physical examination reveals mild abdominal distension with hepatomegaly (3 cm below costal margin). Laboratory findings show hemoglobin 9.8 g/dL, leukocyte count 7,200/μL, and eosinophilia at 8%. Stool microscopy reveals barrel-shaped eggs with flattened opercular ridges. Which of the following organisms is most likely responsible for this patient's clinical presentation?
Answer choices
- AAscaris lumbricoidesCorrect answer
- BSchistosoma mansoni
- CTrichuris trichiura
- DNecator americanus (hookworm)
- EStrongyloides stercoralis
- FEntamoeba histolytica
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