Inflammatory Bowel Disease USMLE Step 1 Practice Question
A 19-year-old woman presents to the emergency department with a 3-week history of bloody diarrhea, abdominal pain, and unintentional weight loss of 3.6 kg (8 lbs). She reports crampy right lower quadrant pain and has had 6-8 loose stools daily. On examination, temperature is 37.8°C, and there is mild right lower quadrant tenderness without an obvious mass. Laboratory studies show: hemoglobin 12.1 g/dL, CRP 8.2 mg/dL, ESR 28 mm/hr. Colonoscopy reveals segmental areas of inflammation in the terminal ileum with intervening areas of normal mucosa (skip lesions) and a cobblestone appearance of the mucosa. Rectal examination is normal with no perianal findings. Which of the following is the most likely diagnosis?
Answer choices
- ACrohn diseaseCorrect answer
- BUlcerative colitis
- CInfectious colitis (Campylobacter jejuni)
- DCeliac disease
- EBehçet disease with gastrointestinal involvement
- FIrritable bowel syndrome
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