Meckel's diverticulum perforated by a foreign body: A rare but potentially fatal cause of acute abdomen

A 64-year-old man consulted in the Emergency Department for pain in the right iliac fossa over the past 3 hours, no fever and with normal blood tests. His personal history included previous episodes of reno-ureteral colic. The abdominal examination showed tenderness in the right iliac fossa with rebound.

A contrast-enhanced computed tomography (CT) of the abdomen and pelvis was performed. In the right iliac fossa, a rounded, elongated structure, measuring 24 x 28mm (diameter x length), was visible protruding from the antimesenteric border of the distal ileum wall. The structure showed marked inflammatory changes in the adjacent mesenteric fat. In addition, a hyperdense, linear image 27mm in length, consistent with a foreign body (e.g., fishbone or bone fragment) was identified, crossing and perforating the diverticulum wall, and protruding into the adjacent mesenteric fat (Figures 1, 2). The findings were suggestive of Meckel's diverticulum perforated by a foreign body with inflammatory changes. There was no significant pneumoperitoneum or ascites. The cecal appendix was normal in calibre and morphology, with no surrounding inflammation (Figure 3). Surgery was performed, confirming the radiological findings, the foreign body being a fishbone (Figures 4, 5, 6).

Meckel's diverticulum is the most common congenital anomaly of the gastrointestinal tract, occurring in 2-3% of the population. It arises as a result of the non-obliteration of the omphalomesenteric duct during pregnancy. Meckel's diverticulum is located on the antimesenteric border of the ileum, within 100 cm of the ileocecal valve. It is a true diverticulum, lined by normal mucosa of the small intestine, although it may also contain ectopic mucosa [1,2].

In most patients, Meckel's diverticulum is asymptomatic and discovered incidentally. The clinical symptoms are nonspecific and are due to complications of the diverticulum, which in decreasing order of frequency include intestinal bleeding, intestinal obstruction, diverticulitis, perforation (secondary to inflammation, gangrene, peptic ulcer, foreign body ingestion or intestinal obstruction), intussusception, chronic recurrent pain, strangulation, volvulus, insertion of the diverticulum into a hernia, enterolith formation and malignancy [1,2].

Most complications manifest during childhood, although they can also occur during adult life. The diagnosis of a complicated Meckel´s diverticulum is challenging as the clinical presentation overlaps with other causes of acute abdominal pain [2,3].

On computed tomography, uncomplicated Meckel's diverticulum is difficult to distinguish from the normal small intestine. When complicated, it can be seen as a blind saccular stucture of variable size in continuity with the small intestine, generally containing fluid or gas, with associated wall thickening, hyper-enhancement, and surrounding mesenteric inflammation [4].

Symptomatic Meckel's diverticula should always be treated surgically [1]. The treatment of incidentally discovered asymptomatic diverticula is a controversial issue, since the risks inherent in surgery must be weighed against the risk of complications throughout life (4% risk in patients up to 20 years and 2% up to 40 years) [5].

On the whole, perforated Meckel´s diverticulum is a rare complication of an already infrequent disease process that we should include in the differential diagnosis of patients with acute abdomen, especially those presenting with pain in the right iliac fossa. A prompt diagnosis is crucial, due to the potential risks if delayed.

Written informed patient consent for publication has been obtained.