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CHAPTER 66

Gastrointestinal Duplications

Auwal M Abubakar
Ralf-Bodo Troebs

Introduction • Remnants of embryologic diverticula: This may explain the higher
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Gastrointestinal duplications (GIDs) are rare congenital malformations. frequency of GID found in the terminal ileum because there are
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They can arise anywhere from the mouth to the anus. Due to the rarity usually numerous diverticula found during development. The pres-
of these lesions, they frequently present both diagnostic and therapeutic ence of heterotopic mucosa, the mesenteric location of GID, and the
challenges. They may be unexpectedly encountered intraoperatively, presence of tubular duplications puts this theory to question.
and appropriate surgical management requires that the attending sur- • Partial twinning: This can explain duplications of the hindgut.
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geon be familiar with the pathology and clinical characteristics of GID. These are usually associated with malformations of the genitouri-
Demographics nary tract.
Gastrointestinal duplications occur with a prevalence of 1:4,500 births. • Environmental factors such as trauma or hypoxia: 18,19 In early foetal
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In most series, there is no sex predilection. Even though GID is rare, development, environmental factors may lead to duplications, and
many reports exist with large numbers of patients accumulated over duplications may, in fact, be a part of the spectrum of intestinal atresias.
long periods. Few reports, however, come from Africa. 9–11
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About 60–70% of patients present before the age of 2 years. 6,8,12 In Pathology
Africa, due to more difficulties with diagnosis, patients may present at Gastrointestinal duplications are rare congenital malformations. They
an older age. 11 generally have the following characteristics irrespective of location:
Embryology • They are in or adjacent to the wall or part of the gastrointestinal
tract and are consistently on the mesenteric side.
There are many theories on the embryology of GID. None of these
theories, however, is able to explain all types of duplication. The pres- • They share a common blood supply with the native bowel.
ence of heterotopic tissue in duplications and the consistent mesenteric
• They have a definite smooth muscle coat and are lined by alimen-
location of duplications has put many of these theories to question.
tary tract mucosa that may be similar to the adjacent bowel or het-
These embryological theories include the following:
erotopic tissue.
• Split notochord syndrome: 13,14 GID is related to the development of The most common site of GID is the ileum, followed by the
neuroenteric canals, which is related to the thoracic duplications that oesophagus, colon, and jejunum (Table 66.1).
have associated abnormalities of the cervical and thoracic vertebrae.
Grossly, GIDs are spherical (Figure 66.1) in 82% of the cases;
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• Abnormalities of recanalisation of the solid stage: It is only some these are the most prevalent type at all levels and do not commonly
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part of the foregut that undergoes recanalisation, and this process communicate with the adjacent bowel. The remaining GIDs are tubular,
occurs on both the mesenteric and antimesenteric sides of the more extensive, more likely to have heterotopic gastric mucosa,
bowel, whereas duplications are found only on the mesenteric side. and usually communicate with the adjacent bowel, most commonly
Table 66.1: Summary of distribution of locations of 431 gastrointestinal duplications in 395 patients from six studies.
Location Bower et al. Hocking et al. Holcomb et al. Stringer et al. Karnak et al. Pulgandla et al. Totals (%)
(1978) 6 (1981) 7 (1989) 8 (1995) 9 (2000) 10 (2003) 11
Oropharyngeal 0 – 0 2 1 – 3 (<1)
Oesophagus 15 8 21 15 7 – 66 (15)

Stomach 8 8 8 10 1 6 41 (10)
Duodenum 4 1 2 3 3 7 20 (5)
Jejunum/ileum 34 32 47 21 17 51 202 (47)
Colon 12 4 15 10 9 5 55 (13)
Rectum 2 5 5 6 2 4 24 (6)
Thoracoabdominal 1 2 3 6 2 0 14 (3)
Others 2 0 0 4 0 0 6 (1)
Totals (duplications/ (78/64) (60/53) (101/96) (77/72) (42/38) (73/72) 431 (100)
patients)