Hirschsprung's disease Flashcards
(15 cards)
What is Hirschsprung’s disease?
- caused by an aganglionic segment of bowel due to a developmental failure of the parasympathetic Auerbach and Meissner plexuses.
- A congenital condition where nerve cells of the myenteric plexus are absent in the distal bowel and rectum.
What is the pathophysiology of the myenteric plexus?
The myenteric plexus, also known as Auerbach’s plexus, forms the enteric nervous system (the brain of the gut) and runs along the bowel wall as a complex web of neurones, ganglion cells, receptors, synapses, and neurotransmitters.
What is the role of the myenteric plexus?
It is responsible for stimulating peristalsis of the large bowel; without this stimulation, the bowel loses its motility and stops being able to pass food along its length
What is the key pathophysiology in Hirschsprung’s disease?
The absence of parasympathetic ganglion cells that fail to migrate down to the distal colon and rectum during fetal development.
What happens when the entire colon is affected?
When the entire colon is affected, this is called total colonic aganglionosis.
What does the aganglionic section of colon lead to?
This section doesn’t relax, causing it to become constricted, leading to loss of movement of faeces and obstruction in the bowel.
What are the symptoms proximal to the obstruction?
The bowel becomes distended and full.
What syndromes can Hirschsprung’s disease be associated with?
It can be associated with Down syndrome, neurofibromatosis, Waardenburg syndrome, and MEN type II.
How can Hirschsprung’s disease present?
It can present with acute intestinal obstruction shortly after birth, delay in passing meconium (>24 hours), chronic constipation since birth, abdominal pain and distention, vomiting, poor weight gain, and failure to thrive
What is Hirschsprung associated enterocolitis?
It is inflammation and obstruction of the intestine occurring in around 20% of neonates with Hirschsprung’s disease, typically presenting within 2-4 weeks of birth.
What are the symptoms of Hirschsprung associated enterocolitis?
Symptoms include fever, abdominal distension, diarrhoea (often with blood), and features of sepsis.
- it’s life threatening and can lead to TMC and perforation of the bowel
What is the management for Hirschsprung associated enterocolitis?
Urgent antibiotics, fluid resuscitation, and decompression of the obstructed bowel.
What investigations are used for Hirschsprung’s disease?
Abdominal x-ray helps diagnose intestinal obstruction and demonstrates features of HAEC; rectal biopsy confirms diagnosis by showing absence of ganglionic cells.
What is the management for Hirschsprung’s disease?
Unwell children and those with HAEC need fluid resuscitation and management of intestinal obstruction, including rectal washout/bowel irrigation, IV antibiotics in HAEC, and surgical removal of the aganglionic section of bowel.
What are the consequences of surgery for Hirschsprung’s disease?
Surgery is usually successful but can result in long-term disturbances in bowel function and some degree of incontinence.
