Gastro - Hirschsprung's Disease Flashcards
What is Hirschsprung’s disease?
Neural crest cells fail to migrate to the colon this causes absent nerve cells of the myenteric plexus
Myenteric plexus forms the enteric nervous system
What is another name for the myenteric plexus?
Auerbach’s plexus
Where is the myenteric plexus?
All along the bowel wall
What does the myenteric plexus do?
Stimulates peristalsis of the large bowel
No stimulation causes the bowel to lose it’s motility, no longer able to pass contents
What is the key feature of Hirschsprung’s disease?
Absence of parasympathetic ganglion cells
How much of the colon is affected in Hirschsprung’s?
Varies between patients from small area to entire colon
What is it called when the entire colon lacks parasympathetic neurones?
Total colonic aganglionosis
What happens to the aganglionic section of the colon?
Does not relax
Becomes constricted
This leads to a loss of movement of faeces and obstruction in the bowel
Proximal to obstruction bowel becomes distended and full
Why is family history so important in Hirschsprung’s?
Family history greatly increases risk
What other syndromes are associated with Hirschsprung’s?
Usually isolated
- Downs syndrome
- Neurofibromatosis
- Waardenburg syndrome
- Multiple endocrine neoplasia II
What are the key symptoms of Waardenburg syndrome?
Pale blue eyes
Hearing loss
Patches of white skin and hair
How does Hirschsprung’s present?
- Delay in passing meconium, > 24 hours
- Chronic constipation since birth
- Abdominal pain
- Abdominal distension
- Vomiting
- Poor weight gain and failure to thrive
What can present 2-4 weeks after birth in babies with Hirschsprung’s?
Hirschsprung-Associated Enterocolitis
What is Hirschsprung-Associated Enterocolitis?
Inflammation and obstruction of the intestine
- Fever
- Abdominal distension
- Diarrhoea can be with blood
- Sepsis features
What can Hirschsprung-Associated Enterocolitis lead to?
LIFE THREATENING
- Toxic megacolon
- Bowel perforation
Abdominal xray helpful to diagnose intestinal obstruction
How is Hirschsprung-Associated Enterocolitis managed?
Urgent IV antibiotics
Fluid resuscitation
Decompression of obstructed bowel
