Introduction:It is due to absence of autonomic ganglion cells in Auerbach's plexus of distal large intestine. It commences at internal sphincter and progresses for variable distance proximally. Lack of peristalsis causes colonic obstruction. It affects 1 in 5000 live births. Male : female ratio 4:1.75% cases confined to recto-sigmoid, 10% cases have total colonic involvement. 80% present in neonatal period with delayed passage of meconium followed by increasing abdominal distension and vomiting.
Symptoms:
Neonatal age:
- Delayed Passage of meconium
- Constipation
- Progressive abdominal distension
- Vomitings
- Enterocolitis
Older child:
- Constipation
- Abdominal distension
Investigations:
Plain abdominal x-ray will confirm intestinal obstruction.
Barium enema - Contracted rectum, cone shaped transitional zone and proximal dilatation.
Anorectal manometry - No recto-sphincteric inhibition reflex on rectal distension
Rectal biopsy shows: Absent ganglion cells in submucosa, Increased acetylcholinesterase
cells in muscularis mucosa, Increased unmyelinated nerves in bowel wall.
Treatment:
Initial defunctioning colostomy to relieve obstruction & then definitive pull through procedure with excision of aganglionic segment.
