Inflammatory Bowel Disease USMLE Step 1 Practice Question
An 11-month-old boy presents with sudden onset intermittent episodes of severe crying and leg-drawing posture. He has vomited twice and passed bloody, mucus-laden stools. Vital signs show HR 128/min, RR 26/min, BP 95/60 mmHg, and temperature 38.2°C. Abdominal ultrasound demonstrates a characteristic target sign in the right lower quadrant. Complete blood count shows mild leukocytosis at 13,200/μL. Notably, there is no abdominal distension or evidence of perforation. Which diagnosis best explains these findings?
Answer choices
- AIntussusceptionCorrect answer
- BMeckel diverticulum
- CHirschsprung disease
- DNecrotizing enterocolitis
- EPyloric stenosis
- FInfectious gastroenteritis with secondary intestinal obstruction
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