Duplication cyst with midgut volvulus in a neonate: an unusual presentation

Discussion

Malrotation of gut with midgut volvulus is one of the common causes of neonatal intestinal obstruction presenting as bilious vomiting. Patients with malrotation of gut may develop midgut volvulus due to their narrow mesenteric base on which it twists resulting in ischaemia of bowel requiring urgent laparotomy and a Ladd’s procedure.

The abnormalities of intestinal rotation represent a spectrum with many variations. A reverse volvulus like in our case is a rare presentation. Malrotation with midgut volvulus is managed by Ladd’s procedure whose steps are (1) volvulus is untwisted usually in an anticlockwise direction for 270̊° (clockwise in our case because of reverse volvulus), (2) Ladd’s band divided resulting in straightening of the duodenum, (3) duodeno-colic isthmus widened, which places the small bowel on the right side and colon to the left in the abdominal cavity and (4) an optional appendicectomy, usually an inversion type, is done to help prevent any diagnostic dilemma of appendicitis in future.

In a review by Verma et al in his study of 298 neonates over 15-year period, an EDC was the causing intestinal obstruction in 3.7% of neonates.3 About 75% of babies with EDCs present in the infancy. Fifty-three per cent of EDCs occurs in jejunum and ileum, which is slightly more common in male children.4 Jejunal duplication could have also added to the pain and relative intestinal obstruction in our case. There are two variants of enteric duplications with the cystic variant being more common than tubular variant. The surgical option for a cystic EDC involves en bloc resection of the adjoining small bowel with EDC since both share a common blood supply. The term alimentary tract duplication is used for congenital lesions having three characteristics: (1) the presence of a well-developed coat of smooth muscle; (2) an epithelial lining representing some portion of the intestinal tract mucosa and (3) intimate anatomic association with some portion of the gastrointestinal tract.5 No history of melena or pallor signifies that the patient did not bleed, although in our case, there was no evidence of ectopic gastric mucosa on histopathology. Technetium-99m scintigraphy is helpful in diagnosis of EDC and differentiating it from the mesenteric cyst and also the fact that most cystic EDCs are not communicating with lumen of bowel.

An acute presentation of these cysts has not been reported earlier leading to volvulus of midgut leading to gangrene, but in our case, the bowel was well preserved.6 EDC on ultrasound shows the characteristic double-wall sign consisting of an inner hyperechoic rim correlating to the mucosa and submucosa, and an outer hypoechoic layer representing the muscularis propria.7

The incidence of malrotation of gut with EDC together is not well documented in the literature with only a handful of case reports.8 It could sometimes present at a later age, but in our case presented in the neonatal period.9 If the ultrasound shows clearcut findings of volvulus in addition to a large intra-abdominal cyst in a baby with bilious vomiting, the patient can be posted for laparotomy directly.

Management of cystic EDCs is by resection of the EDC with adjacent bowel as both share common blood supply like in our case. The tubular EDCs may be managed with limited cyst resection or with mucosal stripping. A long tubular EDC requires marsupialisation between EDC and adjacent bowel for cyst drainage. Prenatal diagnosis has been instrumental in planning the treatment of these lesions before the symptom onset or with their complications.10