Helicobacter pylori - Portal Neonatal

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Congenital problems of the gastrointestinal tract
Exomphalos
The defect on the anterior abdominal wall in cases
of exomphalos lies in the midline. Viscera herniate
through this defect but remain contained within
an avascular hernial sac comprising peritoneum
and amniotic membrane (Figure 2.8). The size of
the defect and hence the size of the sac may vary
from a small swelling at the base of the umbilical
cord (exomphalos minor) to a much larger sac
containing liver and a large proportion of the small
intestine (exomphalos major). The embryological
origins of exomphalos are believed to be failure of
complete closure of the anterior abdominal wall
around a persistent body stalk. Visceral contents
continue to develop within this body stalk and
thus remain outside the abdominal cavity. Whilst
the precise etiology of exomphalos is not clear, it is
well recognized that exomphalos often co-exists
with a number of other congenital abnormalities
and this may suggest at least in part a genetic
component. Associated abnormalities include
Beckwith–Wiedemann syndrome, the trisomies 13,
18 and 21 and the upper and lower midline
associations.
Gastroschisis
The anterior abdominal wall defect in cases of
gastroschisis is of full thickness and typically to
the right of the umbilical cord. Unlike exomphalos
there is no sac covering the eviscerated intestine,
which is usually dilated and inflamed (Figure 2.9).
Figure 2.8 Clinical appearance of an infant with exomphalos.
The abdominal contents are enclosed within an
avascular hernial sac.
The liver is not herniated. The precise embryological
basis of gastroschisis is unclear and a number
of hypotheses have been proposed. The fact that
gastroschisis is rarely associated with any other
congenital abnormalities, with the exception of
intestinal atresias and malrotation, suggests that it
is most likely to have a separate embryological
basis from the events resulting in exomphalos.
Treatment
It is now common for these two abnormalities to be
detected in the antenatal period; delivery in a
specialist center with pediatric surgical facilities is
recommended. There is no consensus concerning
the timing or mode of delivery of these babies and
there is no convincing evidence to suggest that
preterm or Cesarean section delivery confer any
distinct advantage. 49–51 In gastroschisis, however,
delivery is commonly induced at 37 weeks’ gestation
to avoid late-gestation fetal death. What is of
paramount importance is protection of the intestine
and prevention of fluid loss in cases of gastroschisis
from the moment of delivery. In exomphalos the
hernial sac confers a degree of protection to the
intestine. In cases of gastroschisis the eviscerated
intestine should be wrapped in clingfilm and
adequate support provided to prevent fluid loss and
ischemic damage to the bowel. Cases of exomphalos
in which the hernial sac ruptures during delivery
should subsequently be treated as for gastroschisis.
Surgery and attempted closure should take place as
Figure 2.9 Clinical appearance of an infant with
gastroschisis. There is no sac enclosing the herniated
intestine, which is thickened and inflamed.