Hirschsprung's disease

Background

• Congenital aganglionosis of colon
  • Usually rectosigmoid area
    • Short segment affects rectum and small amount of distal colon
    • Long segment affects more of colon, proximal intestine
  • Rarely involves more proximal intestine
• 30% associated with a syndrome
• 1:5,000 live births

Clinical Features

• Delayed meconium passage after birth
• 80% present within first month of life
  • May have delayed presentation in milder disease
• Chronic constipation
  • Encopresis
  • Rectal prolapse
• Obstruction symptoms
  • Neonatal toxic megacolon may occur
    • Distended abdomen, bilious vomiting, enterocolitis
• Enterocolitis
  • Diarrhea, rectal bleeding, abdominal distention, fever

Differential Diagnosis

Infant Constipation

• Constipation
• Hirschsprung's disease
• Congenital anorectal malformations
  • Imperforate anus
• Bowel obstruction
• Neurologic disorders
• Encephalopathy
• Spinal cord abnormalities: myelomeningocele, spina bifida, tethered cord
• Meconium ileus
  • Cystic fibrosis
• Metabolic causes
  • Hypothyroidism
  • Hypercalcemia
  • Hypokalemia
  • Diabetes insipidus
• Heavy-metal poisoning
• Medication side effects

Evaluation

• KUB distended colon, empty rectum
  • Enterocolitis: distention, bowel wall thickening
  • Obstruction: air fluid levels
• Barium/contrast enema will show narrowed colon and dilated intestine above
  • Sensitivity 70% and specificity of 83%
• Diagnosis requires rectal biopsy (consult GI)

Management

• Consult pediatric surgeon for operative management
  • ED management may include gastric and rectal decompression
  • Treat enterocolitis with broad spectrum antibiotics
• Supportive fluid and electrolyte replacement

Disposition

• Admit if symptoms of obstruction, enterocolitis

See Also

• Constipation (peds)