Hirschsprungs disease

Question 1

Pathophysiology

Answer 1

Absence of parasympathetic ganglion in mesenteric and submucosal plexus of the rectum and sometimes the colon
Ganglion cells arise in neural crest and migrate with the vagal nerve fibres along the intestine
Arrive in proximal colon by w8 and rectum by w12
Arrest in migration => aganglionic section => unable to relax => functional obstruction

Question 2

Clinical features

Answer 2

FH
Down’s syndrome
Neonatal: abdominal distension; failure to pass meconium; vomiting
Older infants and children: chronic, resistant constipation; rarely get overflow soiling; early satiety, abdo discomfort and distension => poor growth; abdo distension with palpable loops of colon; empty rectum

Question 3

Enterocolitis

Answer 3

Most of mortality associated with Hirschsprungs
Abdo pain
Fever
Foul-smelling, possibly bloody diarrhoea

Question 4

Management

Answer 4

Surgical - Swenson’s
Remove section of bowel and create anastomoses
May require temporary colostomy to allow bowel to return to normal size