Immunology USMLE Step 1 Practice Question
A 27-year-old woman presents with acute watery diarrhea beginning 2 days after arriving in Mexico. Vital signs: BP 118/76, HR 88, RR 16, Temp 37.2°C, SpO2 98% on room air. She denies fever, bloody stools, and abdominal cramping. Stool studies are negative for blood and leukocytes. She takes no medications. The causative organism produces an enterotoxin whose intracellular mechanism most resembles which of the following bacterial toxins?
Answer choices
- AShiga toxin
- BTetanus toxin
- CDiphtheria toxin
- DCholera toxinCorrect answer
- EBotulinum toxin
- FPertussis toxin
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