Helicobacter pylori - Portal Neonatal

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Congenital problems of the gastrointestinal tract
Figure 2.5 Variants of ileal atresia. (a) Type 1 due to an internal web (not shown) with no mesenteric defect; (b) type 2
atresia with blind ends joined by a fibrous cord; (c) type 3(a) – blind ends separated with a mesenteric defect; (d) type 3(b),
in which the ileum is coiled like an ‘apple peel’ around a single vessel and completely separated from the proximal dilated
duodenum; (e) type 4 or multiple atresias.
atresia arises from a complete obliteration of the
intestinal segment into a fibrous cord, which joins
two blind ends and runs in the free edge of the
mesentery. There is no mesenteric defect and once
again the total bowel length is usually normal. In
both type 3(a) and type 3(b) atresia the intestine is
likely to be shortened and this may have significant
clinical consequences. Type 3(a) atresia
consists of blind-ending proximal and distal bowel
with no connection and an often large mesenteric
defect. The blind ends are often physiologically
abnormal with decreased or absent peristaltic
activity, which may give rise to torsion, distension
or perforation. Type 3(b) atresia, also known as
apple peel atresia because of its gross morphology,
may involve massive intestinal loss. It consists of
intestinal atresia near the ligament of Treitz, oblit-
eration of the superior mesenteric artery (SMA)
beyond the origin of the middle colic branch and
absence of the dorsal mesentery. The remaining
intestine is coiled helically (like an apple peel)
around a single perfusing vessel, often has
impaired vascularity and is almost inevitably
short. Furthermore, there may be additional
segments of type 1 or 2 atresia within the apple
peel segment. Such a configuration probably arises
from occlusion of the SMA due to thrombus,
embolus or strangulation as part of a midgut volvulus.
In type 4 atresia there are multiple atretic
segments and the intestine may resemble a string
of sausages. Overall bowel length is usually shortened
and the intestine grossly dilated. It has been
proposed that the etiology of type 4 atresia may be
due to failure of recanalization of solid epithelial-