Is Meckel's diverticulum a true diverticulum?

Meckel's Diverticulum is a True Diverticulum

Yes, Meckel's diverticulum is definitively a true diverticulum containing all layers of the intestinal wall. 1

Anatomical Characteristics

• Meckel's diverticulum is a saccular, blind-ending structure located on the antimesenteric border of the distal ileum 1
• It contains all layers of the intestinal wall, which is what defines it as a true diverticulum 1
• This congenital anomaly is present in approximately 2% of the general population 2
• The average length of symptomatic Meckel's diverticulum is around 55 cm 3

Embryological Origin

• Meckel's diverticulum represents a persistent remnant of the omphalomesenteric duct (vitellointestinal duct) 3
• Unlike false diverticula (which contain only mucosa and submucosa), Meckel's diverticulum contains all intestinal wall layers including:
  • Mucosa
  • Submucosa
  • Muscularis propria
  • Serosa 1

Histopathological Features

• Histopathological examination often reveals:
  • Normal intestinal mucosa
  • Ectopic tissue in approximately 50% of cases 3
  • Gastric mucosa is the most common ectopic tissue (42.86% of cases) 3
  • Pancreatic tissue is found in about 5.71% of cases 3
  • Both gastric and pancreatic tissue may be present in rare cases (1.43%) 3

Diagnostic Considerations

• Meckel's diverticulum is often difficult to diagnose and may be confused with other conditions 4
• CT enterography can help identify Meckel's diverticulum and exclude other etiologies 5
• Meckel scan (99mTc pertechnetate scintigraphy) is particularly useful for detecting ectopic gastric mucosa in the diverticulum 2
• The diagnostic yield of small bowel capsule endoscopy is limited (up to 50%) 4

Clinical Significance

• Most Meckel's diverticula remain asymptomatic throughout life 1
• When symptomatic, it can present with:
  • Painless rectal bleeding (classic presentation, especially in children) 2
  • Small bowel obstruction 1
  • Diverticulitis 1
  • Perforation 1
  • Volvulus 6

Distinction from Other Conditions

• Meckel's diverticulum must be differentiated from intestinal duplication cysts, which can have similar clinical presentations and histological features 7
• Unlike other diverticula in the GI tract (such as colonic diverticula which are typically false diverticula), Meckel's is a true diverticulum 1
• When located in the pelvic region, it can mimic adnexal pathology, creating diagnostic challenges 6

Management Considerations

• Definitive treatment for symptomatic Meckel's diverticulum is surgical resection 4
• Management of incidentally discovered Meckel's diverticulum remains controversial, though recent evidence favors resection 4
• Surgical options include diverticulectomy or resection of the segment of bowel containing the diverticulum 3