Meckel's diverticulum

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Classification according to ICD-10
Q43.0 Meckel's diverticulum
ICD-10 online (WHO version 2019)
Meckel's diverticulum

The Meckel's diverticulum ( "Meckel's diverticulum" diverticulum ilei ) - named after the German anatomist Johann Friedrich Meckel (1781-1833) - is a protuberance of the jejunum ( jejunum ) and ileum ( ileum ), which is a radical of the embryonic yolk passage ( Omphaloenteric duct , the connection to the yolk sac ).

In the human newborn this diverticulum is located approx. 30–50 cm, in adults 60–90 cm before the entry of the ileum into the appendix (separated by the ileocecal valve ), in the side of the intestinal wall facing away from the mesenteric attachment.

The first description comes from Wilhelm Fabry (Fabricius Hildanus) from 1598. Johann Friedrich Meckel recognized the embryonic origin of the diverticulum.

frequency

The frequency is indicated differently depending on the perspective. According to pediatric autopsy studies , it is found in 1.5% of all cases; Surgeons see it more often with 3.2–4.5% when they e.g. B. look for it on the occasion of an appendix operation .

With 70% of cases, men are affected much more frequently than women.

It is more common in omphaloceles , malrotation , atresia of the intestine, congenital heart defects and trisomy 18 .

Medical importance

Almost half of all diverticula cause symptoms in the first two years of life. Later on, Meckel's diverticula usually do not cause any symptoms. However, if there is an opening between the small intestine and the diverticulum, intestinal contents can enter the diverticulum and build up there. This can lead to inflammation . The symptoms then hardly differ from acute appendicitis : fever, nausea and severe right-sided abdominal pain. In such acute cases, surgery is the only sensible therapy.

In over 30–50% of cases, the diverticulum can contain gastric mucosa - usually of the corpus type - or, less often (approx. 5%) cells of the pancreas , instead of the usual mucous membrane of the small intestine . The acidification of such cells can cause ulcers and bleeding to occur. Due to the stomach acid, the bleeding can be noticed as black melena . The ulcers are usually located at the base of the diverticulum. Rarely, a breakthrough and inflammation of the peritoneum ( perforation peritonitis ) can occur.

Meckel's diverticulum is rarely responsible as the cause of bleeding in the digestive tract : 3–5% of the bleeding originates from the small intestine, 30% of which from a Meckel's diverticulum. However, bleeding in small children is most often caused by a Meckel's diverticulum if there are no traces of injury. If an ectopic ulcer is suspected , the diagnosis can be confirmed, especially in children, by sodium- 99m technetium-pertechnetate scintigraphy , as the isotope used is particularly concentrated in the gastric mucosa.

The diverticulum can rarely protrude into the lumen of the ileum or colon as an intussusception .

If a cord of connective tissue remains between Meckel's diverticulum and the navel - as a rule, this dissolves when the yolk duct recedes - this can be the cause of a brid ileus . If this cord remains completely open, one speaks of a "persistent omphaloenteric duct"; on the other hand, if the cord, which is open on the inside, closes at both the navel and the intestinal attachment, one speaks of a “yolk duct cyst”.

diagnosis

As a rule, a Meckel's diverticulum is discovered accidentally during a laparoscopy or laparotomy , as it is usually clinically silent. Because about 50% of the ectopic gastric mucosa is present, it can best be visualized by means of scintigraphy with sodium - 99m technetium pertechnetate (Na 99m TcO 4 ). If the result is negative, if there is no acute abdomen , a contrast agent enema can be performed. Push endoscopy seems to be a promising method . Computed tomography and abdominal sonography are not helpful.

Charles Horace Mayo : "A Meckel's diverticulum is often suspected, often searched for and rarely found."

therapy

During the operation, the independent vascular supply to the diverticulum is usually cut off and the base is removed (resected). The resulting opening in the intestine is sewn across. A segment resection may be necessary for very large diverticula .

Legal issues

If a Meckel's diverticulum is found by chance (gynecological, biliary or appendix laparoscopy), this finding must be documented. If a complication of this diverticulum occurs a short time after the diagnosis , surgeons , especially in the USA , were accused of malpractice and brought an action for damages. However, if the surgeon resects the diverticulum and a complication occurs, this can be interpreted at his expense (unauthorized action with disadvantageous consequences for the patient) or it does not have to be paid for by the patient, unless otherwise agreed. A solution to this dilemma is still pending.

See also

literature

  • Lauren M. Allister, Ruth Lim, Allan M. Goldstein, Jochen K. Lennerz: Case 10-2017: A 6-month-old Boy with gastrointestinal bleeding and abdominal pain. New England Journal of Medicine 2017; Volume 376, Issue 13 of March 30, 2017, pages 1269-1277; doi: 10.1056 / NEJMcpc1616020 (Clinical case description of a Meckel's diverticulum in a six-month-old baby with blood in the stool and abdominal pain)

Individual evidence

  1. ↑ a b c d e f g Marcel Bettex (ed.), Max Grob (introduction), D. Berger (arrangement), N. Genton, M. Stockmann: Kinderchirurgie. Diagnostics, indication, therapy, prognosis. 2nd, revised edition, Thieme, Stuttgart / New York 1982, 7.80, ISBN 3-13-338102-4 .
  2. ^ JF Meckel: Contribution to comparative anatomy. Reclam, Leipzig, 1808.
  3. ↑ W. Schuster, D. Färber (editor): Children's radiology. Imaging diagnostics. Vol. II, p. 397ff, Springer 1996, ISBN 3-540-60224-0 .
  4. ↑ W. Schuster, D. Färber (editor): Children's radiology. Imaging diagnostics. Vol. I, p. 73, Springer 1996, ISBN 3-540-60224-0 .

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