This week’s edition of the Step 1 Question of the Week is about parasites. See if you can answer the question and then watch the video to learn the correct answer as well as the rationales for each option.
A 21-year-old female presents to the clinic because of a 2-day history of fever, abdominal pain, and bloody diarrhea. The patient recently returned from Peru. A few days before coming home, the patient ate chicken skewers with rice sold by a street vendor. Temperature is 38.5°C (101.3°F). Physical examination reveals that the abdomen is diffusely tender to deep palpation but is negative for rebound tenderness. A stool sample is positive for a nonmotile, gram-negative bacterium.
The most likely infecting organism invades the host’s immune system through which of the following cells?
A. Goblet cells
B. Microfold cells
C. Paneth cells
D. Parietal cells
E. Tuft cells
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