Oesophageal atresia (in short)
- Oesophageal atresia (OA) encompasses a group of congenital anomalies comprising of
an interruption of the continuity of the oesophagus with or without a persistent communication
with the trachea.
- In 86% of cases there is a distal tracheooesophageal fistula, in
7% there is no fistulous connection, while in 4% there is a tracheooesophageal fistula
without atresia.
- OA occurs in 1 in 2500 live births.
- Infants with OA are unable to
swallow saliva and are noted to have excessive salivation requiring repeated suctioning.
- Associated anomalies occur in 50% of cases, the majority involving one or more of
the VACTERL association (vertebral, anorectal, cardiac, tracheooesophageal, renal
and limb defects).
- The causes are largely unknown and are likely to be multifactorial,
however, various clues have been uncovered in animal experiments particularly defects
in the expression of the gene Sonic hedgehog (Shh).
- The vast majority of cases are sporadic (isolated) and the recurrence risk for siblings is
1%.
- The diagnosis may be suspected prenatally by a small or absent stomach bubble
on antenatal ultrasound scan at around 18 weeks gestation. The likelihood of an atresia
is increased by the presence of polyhydramnios.
- A nasogastric tube should be passed
at birth in all infants born to a mother with polyhydramnios as well as to infants
who are excessively mucusy soon after delivery to establish or refute the diagnosis.
- In OA the tube will not progress beyond 10 cm from the mouth (confirmation is by plain
X-ray of the chest and abdomen).
- Definitive management comprises disconnection of
the tracheooesophageal fistula, closure of the tracheal defect and primary anastomosis
of the oesophagus.
- Where there is a "long gap" between the ends of the oesophagus,
delayed primary repair should be attempted.
- Only very rarely will an oesophageal replacement
be required.
- Survival is directly related to birth weight and to the presence of a
major cardiac defect. Infants weighing over 1500 g and having no major cardiac problem
should have a near 100% survival, while the presence of one of the risk factors reduces
survival to 80% and further to 30–50% in the presence of both risk factors.
- Source: Pr Lewis Spitz. University College London. Orphanet Journal of Rare Diseases