Embryology: development of GI tract, liver, respiratory system
Human Anatomy · MBBS
Study notes
A 2-year-old has painless rectal bleeding; scan shows a small pouch on the ileum. This is Meckel's diverticulum — the commonest GI anomaly, a remnant of the vitelline duct that should vanish by week 7. It follows the 'rule of 2s': 2% of people, 2 feet from the ileocecal valve, 2 inches long, often presents by age 2, and may contain 2 tissue types (gastric/pancreatic) that ulcerate and bleed. Surgical removal cures it.