A 3-year-old child passes a large quantity of bright red blood per rectum painlessly. He has no abdominal pain, no fever, and is hemodynamically stable. Physical examination is unremarkable. The MOST appropriate diagnostic test to confirm the most likely diagnosis is:
- A Colonoscopy to evaluate for polyps or IBD
- B Barium enema to detect intussusception
- C Technetium-99m pertechnetate (Meckel) scan ✓
- D Stool culture for Shigella and E. coli O157:H7
Explanation
Painless, significant rectal bleeding in a child aged 1–5 years without abdominal distress is the classic presentation of a bleeding Meckel's diverticulum. Meckel's diverticulum (persistence of the vitello-intestinal duct) is located within 2 feet of the ileocecal valve, occurs in 2% of the population, and is lined with ectopic gastric mucosa in 50% of symptomatic cases. The ectopic gastric mucosa secretes acid, causing ulceration of adjacent ileal mucosa and painless hemorrhage. Technetium-99m pertechnetate preferentially concentrates in gastric mucosa, making the Meckel scan (sensitivity 85–90% in children) the diagnostic test of choice. Colonoscopy is preferred for suspected polyps or colitis.
Reference: Ghai Essential Pediatrics, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.