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Overview of Meckel's Diverticulum

Epidemiology, Pathophysiology, Symptoms, Diagnosis, and Treatment

Jul 20, 2009 David Henry

Meckel's diverticulum is the most common congenital disorder of the intestinal tract. Below is an overview of the epidemiology, pathophysiology, diagnosis, and treatment.

About 2% of the population has a Meckel’s diverticulum, and it is more common in males. A Meckel’s diverticulum is considered a “true diverticulum” because it is an outpouching from the intestines that contains all layers of the intestinal wall. It is usually found in the ileum, the third part of the small intestines, within 2 feet of the ileocecal valve, or the junction between the small and large intestines. 60% of Meckel’s diverticula contain tissue that is not normally in the intestines, for example mucosal tissue from the stomach and tissue from the pancreas, colon, uterus, or liver.

Pathophysiology of Meckel’s Diverticulum

A Meckel’s diverticulum forms in the 8th week of gestation if the vitelline (omphalomesenteric) duct fails to obliterate, or disappear. Gastric mucosa within the Meckel’s diverticulum can produce acid and cause ulcers and bleeding within the ileum (part of the small intestines). When the vitelline duct fails to obliterate, a “mesodiverticular band,” or band of fibrous tissue connecting the Meckel’s diverticulum to the mesentery, can remain. The intestines can become tangled around this fibrous band, the lumen (or opening) in the ileum can become occluded, and an obstruction (blockage) can result. Finally, if a Meckel’s diverticulum goes into an inguinal (groin) or femoral hernia sac, it is called a Littre’s hernia.

Symptoms of Meckel’s Diverticulum

Usually a Meckel’s diverticulum is asymptomatic. 2% of the world population has a Meckel’s diverticulum, and about 4% of these people will eventually develop complications. Usually symptoms present in children younger than 2 years of age. The most common findings are bleeding (most common in children), intestinal obstruction (most common in adults), and diverticulitis (inflammation of the diverticula). Also, carcinoid tumors are present in 0.5-3.2% of Meckel’s diverticula that are resected.

Diagnosis of Meckel’s Diverticulum

Meckel’s diverticulum is usually diagnosed when doing an imaging test or surgery for another purpose; only 4% of them are symptomatic. CT scan is not usually useful in detecting Meckel’s diverticula. Enteroclysis is about 75% accurate. And 99m-Tc-pertechnetate radionucleotide scans are 90% accurate in diagnosing Meckel’s diverticula in kids, but less than 50% accurate in adults. Radionucleotide scans and angiography can also localize bleeding within the intestines.

Treatment of Meckel’s Diverticulum

If a Meckel’s diverticulum is causing a complication (bleeding, obstruction, or diverticulitis), the diverticulum should be removed surgically. Any fibrous bands connecting the diverticulum to the mesentery or abdominal wall should also be removed. If the diverticulum is inflamed or perforated, or if there is a bleeding ulcer, that segment of the ileum or intestines should be resected, and the healthy intestines should be anastomosed back together. If the Meckel’s diverticulum is not causing symptoms, it is controversial whether or not to remove it since there is a low likelihood (4%) that complications will develop.

References

Chapter 27: Small intestine. Brunicardi C et al., Eds. Schwartz’s Principles of Surgery. 4th ed. McGraw-Hill, 2005.

eMedicine: Pediatrics: Meckel Diverticulum

The copyright of the article Overview of Meckel's Diverticulum in General Medicine is owned by David Henry. Permission to republish Overview of Meckel's Diverticulum in print or online must be granted by the author in writing.

Diagram of Meckel's diverticulum from the ileum