Meckel diverticulum is a true intestinal diverticulum that
results from the failure of the omphalomesenteric duct to
obliterate during the fifth week of fetal development
1. In
1809, Johann Friedrich Meckel published a meticulous
description of its anatomy and embryonic origin, and it is
known by his name
2. It is the most common congenital
anomaly of the gastrointestinal tract and has an incidence of 2-3%
1. Meckel's diverticulum occurs on the antimesenteric
border of the ileum and may be located 10-150 cm from the
iliocecal valve
4. It contains all normal layers of the intestinal
wall and in approximately 50 % of cases ectopic or heterotopic
tissue from gastric, pancreatic, duodenal, colonic or biliary
mucosa are found
3. Clinically important manifestations of
Meckel's diverticulum occur primarily in childhood, with 60
percent of patients becoming symptomatic before age ten and
70 percent before age 40
5. The most common presentation is
an incidental finding at laparotomy
6. Although mostly
discovered as an incidental finding on laparotomy or
laparoscopy, this entity can be associated with lifethreatening
disease states.
Complications manifest as ulceration-hemorrhage, small
bowel obstruction, diverticulitis and perforation. Also umblical
anomalies such as fistulas, sinuses, cysts and fibrous bands
between the diverticulum and umblicus and neoplasms are
other very rare complications 7. The risk of complications
ranges from 4-25% in various studies 8,9. Retrospective
studies suggest that the onset and frequency of complications
decrease during life 10. Bleeding (25%) is the most common
complication especially occuring in children and it typically
presents as hematochezia 11. The hemorrhage is a result of
heterotopic gastric mucosa leading to ulceration. The most
useful method of detection of a Meckel diverticulum is
Technetium-99m scanning. This method depends on ulceration
and bleeding due to the heterotopic gastric mucosa 8.
Most adults present with obstruction (33%), diverticulitis
(30%) or both 9.Several mechanisms may cause obstruction.
The diverticulum may be the leading point for an
intussusception or volvulus around a fibrous band by which the
diverticulum remains attached to the umbilicus. Other
mechanisms of obstruction include entrapment of bowel within
an internal hernia, entrapment between the mesentery and a
mesodiverticular band, strangulation of the diverticulum in an
external hernia 4. Our patient has been operated as
incarcerated inguinal hernia and Littre hernia diagnosed at
operation.
Littre's hernia (11%) is an unusual complication of a
Meckel diverticulum. It has been reported originally by Alexis
Littre in 1700 as a small intestinal diverticulum incarcerated in
a femoral hernia but the term is now used to describe the
presence of a Meckel diverticulum in a hernia in any location
12. 50% of Meckel diverticula in Littre hernias occur in the
inguinal region, 20% in a femoral site, 20% in an umblical site
and remanding 10% in other locations 13. In symptomatic
Littre hernia the patient presents with a mass 14. Pain, fever
and vomiting are common symptoms. Although fever and
leucocytosis evolve, mechanical intestinal obstruction mostly
may not be seen in incarcerated or strangulated Littre hernia
14.
The preoperative diagnosis of a Littre hernia is difficult
to establish. In case of mechanical small intestinal obstruction
plain abdominal radiographs may demonstrate air fluid level.
The computurized tomography scans are often nonspecific but
occasionally helpfull. The diagnosis is generally not possible
with computurized tomography unless the diverticulum is
visualized 15. In management of a Littre hernia Meckel
diverticulum must be resected. The accepted treatment is
wedge resection of the diverticulum and repair of the ileum
from within the sac 16. If there is edema or inflamation at the
base of the diverticulum as in our case; resection and
anostomosis of a segment of ileum may be necessary. It may
prevent postoperative stricture of resected segment 16,17.
In conclusion, the Meckel diverticulum may be found in
any type of hernia especially at inguinal site so, incarcerated
hernia should not be attempted to reduce. In treatment of Littre
hernia Meckel diverticulum should be resected and it is better
to perform resection and anostomosis of ileal segment in these
patients to prevent postoperative ileal stricture.
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