Embryology:
Meckel diverticulum is a remnant of the embryonic yolk sac, also known as the omphalomesenteric duct or vitelline duct. This duct connects the yolk sac to the gut in a developing embryo and provides nutrition until the placenta has reached its full capabilities. At week five to week seven of gestation, the duct will separate from the intestine.
Pathophysiology:
If this separation does not occur, residual structures will remain. The most common of these residual structures is Meckel diverticulum, a 3-6 cm outpouching of the ileum along the antimesenteric border 50-75 cm from the ileocecal valve.
Epidemiology:
It is the most common congenital GI anomaly, occurring in 2-3% of infants. The rule of 2s is often cited as Meckel’s diverticula generally occurs in 2% of the population, are present within 2 feet of the ileocecal valve, are two inches long, are twice as common in males as in females, and are most often symptomatic by age two. Meckel diverticulum accounts for 50% of all lower GI bleeds in children less than two years of age.
Presentation:
A child with a Meckel diverticulum usually presents around year one to two of life with painless rectal bleeding from ectopic mucosa most commonly of gastric origin. Stool is typically described as “currant jelly” or “brick” colored. Patients may also present with anemia. Occasionally, Meckel diverticulum is associated with partial or complete bowel obstruction when the diverticulum is the lead point of an intussusception or as a diverticulitis, with or without perforation, which presents similar to acute appendicitis.
Radiography/Labs:
Obtain a CBC to determine if the child has anemia. The most sensitive test is a Meckel scan, which is performed by intravenous infusion of technetium-99m pertechnetate. Mucus-secreting cells of the ectopic gastric mucosa will take up the pertechnetate allowing one to visualize the Meckel diverticulum.
Differential Diagnosis:
The differential diagnosis for Meckel’s diverticulum is broad and includes: appendicitis, colitis, constipation, intussusception, inflammatory bowel disease, volvulus, and urolithiasis.
Surgical Management:
A umbilical port is placed and pneumoperitoneum is established. Two 3-5 mm ports are inserted in each of the lower quadrants. A detailed examination of the peritoneal cavity is performed in order to identify the Meckel’s diverticulum. Once Diverticulum is identified, a wedge or segmental excision is performed. The small bowel is commonly brought extracorporeally through the umbilicus and a hand sewn, single layer small bowel anastomosis is performed. Small bowel is then returned to the peritoneal cavity and incision sites are closed. Alternatively, endoscopic staplers may be used for resection and re-anastamosis, especially in older children.
Complications:
Post-operative complications of laparoscopic Meckel’s diverticulectomy are minimal and include wound infections, small bowel obstruction and rebleeding.
