Meckel's Diverticulum: Embryology, Presentation, and Management

Meckel's diverticulum is a true diverticulum (contains all bowel wall layers) resulting from incomplete obliteration of the omphalomesenteric (vitelline) duct. It is the most common congenital anomaly of the small intestine.

Key Features

• Location: Antimesenteric border of ileum, ~2 feet (60 cm) proximal to ileocecal valve.
• Size: Typically 2–5 cm long, 1–2 cm wide.
• Rule of 2s: 2% prevalence, 2 feet from IC valve, 2 inches long, 2x more common in males, symptomatic by age 2 (though can present at any age).
• May contain ectopic tissue: Gastric (50%), pancreatic, colonic, or endometrial mucosa.

Complications

• Obstruction: Intussusception, volvulus, adhesion bands, incarcerated hernia (Littre's hernia).
• Bleeding: Acid secretion from ectopic gastric mucosa ulcerates adjacent ileal mucosa → painless hematochezia (most common presentation in children).
• Inflammation (Diverticulitis): Mimics appendicitis (RLQ pain).
• Perforation: Rare.

Diagnosis & Treatment

Technetium-99m pertechnetate scan (Meckel scan) detects ectopic gastric mucosa. CT/enteroclysis for obstruction. Asymptomatic diverticula found incidentally: observation. Symptomatic: surgical resection (diverticulectomy or segmental ileal resection).