Q- A 27-year-old man complains of a 2-week history of watery diarrhea and 5 lb. weight loss. He had no similar episodes in the past, did not travel recently, and did not eat out or take antibiotics. He quit smoking last month after 1 PPD for 5 years. His family history is significant of some relatives who are diagnosed with inflammatory bowel syndrome. His examination reveals diffuse mild abdominal tenderness and hyperactive bowel sounds. Stool analysis is negative for blood and ova.
Which of the following supports the diagnosis of ulcerative colitis rather than Crohn’s disease in this patient?
A- History of diarrhea and weight loss
B- Family history of inflammatory bowel syndrome
C- Smoking cessation
D- Negative stool analysis
E- Having the first attack in his twenties
Answer and Explanation
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Smoking has opposite effects on the two main inflammatory bowel diseases:
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Ulcerative colitis: Smoking is protective. Stopping smoking can trigger or worsen UC.
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Crohn’s disease: Smoking worsens disease activity.
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This patient quit smoking recently, which supports ulcerative colitis rather than Crohn’s disease.
Why the other options don’t distinguish UC from Crohn’s:
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A — Diarrhea and weight loss: Seen in both UC and Crohn’s.
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B — Family history of inflammatory bowel disease: Increases risk of both.
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D — Negative stool analysis: Helps exclude infection, but does not differentiate UC vs Crohn’s.
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E — First attack in his twenties: Typical age of onset for both conditions.
The correct answer is C
Key takeaway:
👉 Smoking cessation favors ulcerative colitis, while active smoking is more associated with Crohn’s disease.
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Thank you Dr. Yahaya. I appreciate your response.
The answer is C