Helicobacter pylori - Portal Neonatal

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Congenital problems of the gastrointestinal tract
In cases in which the diagnosis is not clear on
abdominal X-ray or in which midgut malrotation
or volvulus is suspected, a limited upper gastrointestinal
contrast study is indicated. The classical
finding in cases of malrotation is that the duodenojejunal
flexure lies to the right side of the
spine instead of in its normal left-sided position
(Figure 2.3). This finding should prompt urgent
surgical treatment, because of the risk of co-existing
midgut volvulus. The contrast study may also
identify the presence of a stenotic segment or
complete obstruction.
Cases of lower ileal stenosis or atresia are often
more difficult to diagnose and a contrast enema is
invaluable in distinguishing between ileal and
colonic obstruction and could be therapeutic in
cases of meconium ileus (see below).
Conditions affecting the duodenum
Duodenal atresia, duodenal stenosis and annular
pancreas are the most common congenital condi-
Figure 2.2 Abdominal X-ray of an infant with duodenal
atresia showing the ‘double bubble’ appearance
characteristic of duodenal obstruction.
tions to affect the duodenum. All are capable of
giving rise to duodenal obstruction. The incidence
is reported to be between 1 in 5000 and 1 in 10 000
live births. 8
Explanations of the etiology of duodenal atresias
are not universally accepted. Unlike atresias of the
ileum, they are not thought to be due to vascular
accidents and the most widely accepted explanation
is that of failure of recanalization of the
intestinal lumen during early embryonic development.
Classification
There are four basic types of duodenal obstruction
(Figure 2.4). In type 1 there is a stenosis of the
duodenum resulting from a diaphragm or web
partially or totally occluding the lumen. Owing to
the incomplete nature of the obstruction, cases
Figure 2.3 Upper gastrointestinal contrast study of a
case of malrotation. The contrast is seen within the
duodenum (D) and flowing into the upper jejunum (J),
both of which lie completely to the right of the midline.