Hirschsprung's disease

Hirschsprung's disease is caused by an aganglionic segment of bowel due to a developmental failure of the parasympathetic Auerbach and Meissner plexuses. Although rare (occurring in 1 in 5,000 births) it is an important differential diagnosis in childhood constipation.

Pathophysiology

• parasympathetic neuroblasts fail to migrate from the neural crest to the distal colon → developmental failure of the parasympathetic Auerbach and Meissner plexuses → uncoordinated peristalsis → functional obstruction

Associations

• 3 times more common in males
• Down's syndrome

Possible presentations

• neonatal period e.g. failure or delay to pass meconium
• older children: constipation, abdominal distension

Investigations

• abdominal x-ray
• rectal biopsy: gold standard for diagnosis

Management

• initially: rectal washouts/bowel irrigation
• definitive management: surgery to affected segment of the colon (anorectal pull through)