CASE SUMMARY

A 49-year-old white man presented to the emergency department with a 1-day history of constant sharp right lower quadrant abdominal pain. Patient complained of some nausea, but no episodes of vomiting or fever. On examination, bowel sounds were hyperactive. Diffuse tenderness with more appreciation in the right lower quadrant was noted. Rebound tenderness was not present.

Laboratory findings were significant for white blood cell count of 10.2 * 10 ³ /µL (normal 4.8­10.8 * 10 ³ /µL) with 79.4% neutrophils and normal electrolytes. Abdominal X-ray (Figure 1) and CT (Figure 2) were performed.

DIAGNOSIS

Meckel's diverticulum enterolith

CLINICAL, IMAGING, AND SURGICAL FINDINGS

The medical history, physical examination, and radiologic studies were consistent with appendicitis as the most likely differential diagnosis upon presentation. The patient was taken to the operating room for surgical treatment, using a McBurny incision. The appendix appeared normal. After further exploration, a large amount of yellowish fluid and a distended small bowel was noted. A diagnosis of other pathology, such as peptic ulcer disease or small bowel obstruction, was entertained. A second midline incision revealed a distended Meckel's diverticulum with an impacted enterolith (Figure 3). Collapsed distal small bowel and dilated proximal small bowel adjacent to the Meckel's diverticulum were present, explaining the finding on X-ray (Figure 1) and CT scan (Figure 2). The diverticulum and its adjacent small bowel were resected, and a stapled small bowel anastamosis was performed. The patient recovered uneventfully and was discharged home on postoperative day seven.

DISCUSSION

Meckel's diverticulum was first described by Hildanus in 1593 and was later defined by German anatomist and embryologist Johann F. Meckel in 1809. It is a true diverticulum composed of all four layers: mucosa, submucosa, tunica muscularis, and serosa. It is a remnant of the omphalomesenteric duct, arising from the antimesenteric border of bowel. Meckel's diverticulum seems to be associated with the "rule of two"; it occurs in 2% of the population, has a male to female predominance of 2:1, is located about 2 feet from the ileocecal valve, has an average length approximately 2 inches long, 2 types of ectopic mucosa could be involved (gastric and pancreatic), and symptomatic cases usually present before age 2. ¹

Most complications due to Meckel's diverticulum occur in infants and young children. This has resulted in awareness among children's clinicians. This case emphasizes the importance of entertaining such diagnosis in the adult population and in order to allow early surgical treatment in the appropriate clinical setting. The most common presentation in adults is diverticulitis with clinical sign and symptoms of pain and obstruction similar to appendicitis.

The complication rate of Meckel's diverticulum has been reported to be 4.2% in infancy, <3% in adults, and close to 0% in the elderly population. These complications include hemorrhage, obstruction, and perforation. Bleeding occurs from adjacent ileal mucosal ulcers due to acid production from ectopic gastric mucosa in diverticulum. Obstruction occurs secondary to inflammation, intussuception, adhesions, and fecalith, as described in this case. Incarceration of Meckel's diverticulum in a hernia, known as Littre's hernia, has been described. If diverticulitis is suspected, it can be diagnosed using Meckel's scan, which uses Technetium-99 pertechnetate since it is taken up by ectopic mucosa in 80% to 90% of such cases. Perforation can occur as result of progression of diverticulitis. ²

Although it is well established that symptomatic Meckel's diverticulum must be removed, recent literature indicates that asymptomatic nonpathologic diverticulum is best managed by leaving it in place if it is found incidentally. The argument is based on the finding that less morbidity resulted if resection was not performed. The life-long risk of complications is estimated to be up to 4.2%, which decreases with age. In comparison, the lifetime incidence of complications following an operation was noted to be 6.4%. ³

For symptomatic Meckel's diverticulum, small bowel resection is appropriate if an associated ileal ulcer is present, diverticulitis is noted, or a fecalith is the cause of obstruction. Diverticulectomy with transverse closure is used for broad-based stumps. Routine resection of asymptomatic Meckel's diverticulum is not recommended.