Gastrointestinal · Year 2 · from Gastrointestinal

Case 1: Meckel's Diverticulum

Patient Presentation

Demographics: 18-month-old male

Chief Complaint: Painless rectal bleeding

History of Present Illness: Parents noticed brick-red blood mixed with stool during diaper changes for the past 2 days. The child has had three episodes of bloody stools without apparent abdominal pain, fever, or vomiting. He continues to feed normally and is playful between episodes.

Past Medical History: Born at term, uncomplicated delivery, up-to-date on vaccinations

Physical Examination

  • Vital Signs: Temperature 37.0C, HR 120 bpm, BP 85/55 mmHg, RR 24/min
  • General: Alert, active, well-hydrated infant
  • Abdomen: Soft, non-tender, non-distended, no palpable masses, normal bowel sounds
  • Rectal: External exam normal, hemoccult-positive stool

Workup and Results

  • CBC: Hemoglobin 9.2 g/dL (decreased from baseline), MCV 78 fL
  • BMP: Within normal limits
  • Meckel Scan (Technetium-99m pertechnetate scintigraphy): Focal uptake in the right lower quadrant consistent with ectopic gastric mucosa

Technetium-99m pertechnetate scan showing focal uptake in the right lower quadrant (arrow), indicating ectopic gastric mucosa within a Meckel's diverticulum.

Image Source: Case courtesy of Radiopaedia.org

Diagnosis

Meckel's Diverticulum with GI Bleeding

Clinical Correlation to Anatomy

Meckel's diverticulum results from incomplete obliteration of the vitelline (omphalomesenteric) duct during embryonic development. It is a true diverticulum located on the antimesenteric border of the ileum, typically within 2 feet of the ileocecal valve. Approximately 50% contain ectopic tissue, most commonly gastric mucosa, which secretes acid causing ulceration of adjacent ileal mucosa and painless bleeding.

Treatment

  • Surgical resection of the diverticulum with adjacent ileal segment
  • Laparoscopic approach preferred when feasible
  • Blood transfusion if hemodynamically significant

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