While ETEC is known to be the primary cause of Traveler's diarrhea based on its watery characteristic, its heat-labile/stable enterotoxins do not cause inflammation or invasion. On the other hand, EIEC's microbes invade the intestinal mucosa, causing necrosis and inflammation similar to that of Shigella, which leads to watery diarrhea progressing to blood and mucus in the stool. Therefore, I think this question needs to be reviewed to reform the stem to point towards ETEC or change the answer choices.
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16 Sep 2025
Review of Question Vignette or Answer Choices
Question:
A 35-year old man presents with recurrent, watery diarrhea and cramps for over a week. He recently returned from a trip to Africa. A stool sample is negative for ova, parasites, and Clostridium difficile toxin. A colonoscopy shows inflammation and adenomas in the colon. Which microorganism is most likely causing his symptoms?
Options:
A)Staphylococcus aureus
B)Giardia lamblia
C)Vibrio cholerae
D)Entamoeba histolytica
E)Escherichia coli
Review of Question Vignette or Answer Choices
Question:
A 35-year old man presents with recurrent, watery diarrhea and cramps for over a week. He recently returned from a trip to Africa. A stool sample is negative for ova, parasites, and Clostridium difficile toxin. A colonoscopy shows inflammation and adenomas in the colon. Which microorganism is most likely causing his symptoms?
Options:
A)Staphylococcus aureus
B)Giardia lamblia
C)Vibrio cholerae
D)Entamoeba histolytica
E)Escherichia coli