Meckel's diverticulum
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Meckel's diverticulum, a true
congenital diverticulum, is a small bulge in the small intestine present at birth. It is a
vestigial remnant of the
omphalomesenteric duct, and is the most frequent malformation of the
gastrointestinal tract. It is present in approximately 2% of the population, with an equal distribution between males and females, although males more frequently experience symptoms. It is named after
Johann Friedrich Meckel, who first described this type of diverticulum in
1809.
Meckel's diverticulum is located in the distal
ileum, usually within about 60-100 cm of the
ileocecal valve. It is typically 3-5 cm long, runs antimesenterically and has its own blood supply. A memory aid is "
2 percent (of the population) -
2 feet (from the ileocecal valve) -
2 inches (in length)"- only
2% are symptomatic. This association with the number 2 continues with the fact that the above statements are about 2% true.
Also can be present in an indirect hernia, where it is known as "
Hernia of Littre." Furthermore, it can be attached to the
umbilicus, with the possibility of local cysts, torsions of intestine around the intestinal stalk, leading to obstrucion,
ischemia, and
necrosis.
Approximately 98% of people afflicted with Meckel's diverticulum are
asymptomatic. If symptoms do occur, they typically appear before the age of two.
The most common presenting symptom is painless
rectal bleeding, followed by
intestinal obstruction,
volvulus and
intussusception. Occasionally, Meckel's diverticulitis may present with all the features of
acute appendicitis. Also, severe pain in the upper abdomen is experienced by the patient along with bloating of the stomach region. At times, the symptoms are so painful such that they may cause sleepless nights with extreme pain in the abdominal area.
A
technetium-99m (
99mTc) pertechnetate scan is the investigation of choice to diagnose Meckel's diverticula. This scan detects
gastric mucosa; since approximately 50% of Meckel's diverticula have ectopic gastric (
stomach) cells contained within them, this is displayed as a spot on the scan distant from the stomach itself. Patients with these misplaced gastric cells may experience peptic ulcers as a consequence. Other tests such as
colonoscopy and screenings for
bleeding disorders should be performed, and
angiography can assist in determining the location and severity of bleeding.
Treatment is surgical, consisting of a
resection of the affected portion of the bowel.
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Meckel's Diverticulum
