CASE 12038 Published on 27.07.2014

CT of Meckel\'s enterolith

Section

Abdominal imaging

Case Type

Clinical Cases

Authors

Turkington J, Gardiner J

Ulster Hospital, Belfast,
Northern Ireland.
(Elective medical student from University of Otago, New Zealand)
Patient

57 years, female

Categories
Area of Interest Abdomen, Gastrointestinal tract, Small bowel ; Imaging Technique CT-High Resolution
Clinical History
A 57-year-old woman presented with a 1 day history of right iliac fossa pain, nausea and vomiting. Inflammatory markers were elevated with a mild leukocytosis.
Imaging Findings
Oral and intravenous contrast-enhanced CT examination of the abdomen and pelvis showed an unusual structure measuring 2.8 x 3.1 cm in the right iliac fossa that contained an air-fluid level and several foci of calcification dependently within it. It had a thin enhancing wall and mild inflammatory fat stranding around its superior aspect. It was closely related to and medial to distal ileal small bowel loops. (Fig. 1 and 2).

The radiological appearance was felt to represent a Meckel’s diverticulum containing enteroliths with mild surrounding inflammation.
Discussion
Meckel’s diverticula are a common malformation of the GI tract resulting from the improper closure and absorption of the onphalo-mesenteric duct. It follows the “rule of 2’s” in that: it occurs in roughly 2% of the population, it usually occurs around 2 feet (60 cm) from the ileocaecal valve, and is normally 2 inches (5 cm) long [1, 3, 4]. It is often asymptomatic, and may be an incidental finding at surgery or post mortem. There is a lifetime risk of 6% of complications occurring such as gastro-intestinal bleeding, diverticulitis and small bowel obstruction [1].

Enterolethiasis is a complication of Meckel’s diverticula. Motility and pH of the bowel are determining factors for what calculi are formed: the alkaline small bowel favours mineral salt precipitation, while the duodenum and proximal jejunum are acidic and favour bile salts. These calculi are rarely demonstrated radiographically, and if present are demonstrated as peripherally calcified, centrally radiolucent or lamenated stones [1-4].

Not all Meckel’s enteroliths are symptomatic, but they may present as an acute abdomen (diverticulitis or bowel obstruction), or as a chronic complaint. As this is an uncommon presentation, and not all enteroliths are radio-opaque, this diagnosis may be made at the time of surgery [1-4].

On abdominal radiograph it is possible to see radio-opaque stones most frequently in the right lower quadrant, but also potentially in the right upper and left lower quadrants [4]. On CT and MRI, a narrow-necked Meckel’s diverticulum may be seen and if enteroliths are present these are seen as central calcifications [1-4]. It is also possible to identify an enterolith using a small bowel barium study, as it appears as a filling defect in a blind-ended pouch, but this finding may be obscured by barium-filled bowel [4].

Definitive treatment is surgical removal of the section of bowel with diverticulum and anastomoses.

The patient had a laparoscopic resection. Pathology confirmed a Meckel's diverticulum containing calcifications and lined entirely by small intestine-type mucosa. The diverticular lining was ulcerated in areas with some underlying submucosal fibrosis.
Differential Diagnosis List
Meckel's enterolith
Diverticulitis
Appendicitis
Cholelithiasis
Small bowel obstruction
Final Diagnosis
Meckel's enterolith
Case information
URL: https://www.eurorad.org/case/12038
DOI: 10.1594/EURORAD/CASE.12038
ISSN: 1563-4086