What is the likely diagnosis, and what differentials should be considered?
Meckel diverticulitis is most likely given the location. Epiploic appendagitis and omental infarction should also be considered.
Why can you dismiss acute appendicitis as a potential diagnosis?
A normal appendix is seen anterior to the caecum, gas-filled and thin-walled with no surrounding stranding.
Is a Meckel diverticulum a true or false diverticulum? Explain the difference.
Meckel diverticulum is a true diverticulum (i.e all layers of gastrointestinal tract are present in its wall) compared to the far more common colonic diverticula which are false diverticula (lack the muscularis layer).
Where are Meckel diverticula located?
Most (75%) Meckel diverticula are found within 100 cm (two feet) of the ileocaecal valve, and arise from the antimesenteric border of small intestine.
In addition to normal small bowel mucosa, what can be found in Meckel diverticula?
Meckel diverticula are lined with heterotopic mucosa in up to 60% of cases such as: gastric mucosa (most common, ~60%); pancreatic tissue (~6%).
In the right iliac fossa is a blind-ending tubular structure arising from the distal small bowel, which has a markedly thickened wall with extensive surrounding fat stranding. No abscess, no free fluid and no bowel obstruction. The appendix is located anterior to the caecum and is normal in appearance.