Abnormalities Arising From Abnormal Embryological Development ✅ Flashcards
What abnormalities of the GI tract can result from abnormal embryological development?
- Duodenal atresia or stenosis
- Exomphalos
- Gastroschisis
- Meckel’s diverticulum
- Midgut malrotation
- Meconium ileus
- Duplication cysts
- Hirschsprung’s disease
- Anorectal abnormalities
- Intussusception
Where in the GI tract can atresia occur?
At any point
Are GI atresias single or multiple?
Can be either
Are atresias complete or incomplete?
Can be either
What is the most common site of GI atresia?
The duodenum
What is the incidence of duodenal atresia?
1 in 10,000-30,000 live births
Where do most duodenal atresias occur?
At the ampulla of Vater
What can cause a duodenal atresia?
Either a complete mucosal membrane or a blind-ending proximal loop, probably due to failure of canalisation of the duodenum after the 7th week
What causes failure of canalisation of the duodenum after the 7th week?
Ischaemia
What % of cases of duodenal atresia have associated abnormalities?
50%
Give 2 abnormalities that may be associated with duodenal atresia?
- Down’s syndrome
- Prader-Willi syndrome
How might duodenal atresia present?
- Antenatal presentation with polyhydraminos or ‘double bubble’ on ultrasound scan
- Bilious vomiting, usually immediately after first feed
What is the incidence of exomphalos?
1 in 3000
What is exomphalos?
A midline defect of the anterior abdominal wall, where some of the organs line outside of the abdominal cavity
What are the organs encased in in exomphalos?
A membranous sac derived from the amniotic membrane
What organs are contained within the sac in exomphalos?
Vary, but can include stomach, intestine, liver, and spleen
What is the defect classified based on in exomphalos?
Size
What are the classifications of exomphalos?
- Major (>4cm)
- Minor (<4cm)
What is exomphalos frequently associated with?
- Other congenital abnormalities, such as trisomy 13, 18, and 21
- Associated structural problems such as cardiac abnormalities
What % of cases of exomphalos are associated with other structural problems?
75%
When is exomphalos usually identified?
Antenatal scanning
What is the management of exomphalos?
Surgical correction
Do babies born with exomphalos need emergency surgery?
Generally not an emergency providing the intra-abdominal structures are well perfused (but depends on size of defect and if sac remains in tact)
What is the incidence of gastroschisis?
4 per 10,000