Diagnosis

Constipation history taking key components

• Stool patterns: < 3 complete stools; rabbit dropping; hard stools; overflow diarrhoea (>1yr)
• Associated symptoms: distress on stooling; bleed; straining; poor appetite improving with passage of stool (>1yr); retentive posturing (>1yr)
• History: previous constipation; anal fissure; painful bowel movements and bleed a/w hard stools

Idiopathic vs Underlying Disorder

• Timing of onset:
  • Idiopathic: starts after a few wks of life, obvious precipitating factors
  • Not idiopathic: starts at birth
• Passage of meconium
  • Idiopathic: passing within 48hrs
  • Not idiopathic: not passing within 48hrs
• Stool pattern
  • Idiopathic:
  • Not idiopathic: ribbon stool
• Growth
  • Idiopathic: within limits
  • Not idiopathic
• Locomotor
  • Idiopathic: within limits
  • Not idiopathic: locomotor delay
• Diet
  • Idiopathic: insufficient fluid intake, poor diet insufficient fluid intake (>1yr)
  • Not idiopathic

Examination findings suggestive of underlying disorder:

• Perianal fissures; tight or patulous anus
• Gross abdominal distention
• Spine / lumbosacral region: asymmetry of gluteal area, sacral agenesis, hairy patch
• Lower limb deformity e.g. talipes
• Abnormal reflexes

Investigation

• Digital rectal exam by competent individual able to determine Hirschsprung’s disease in an infant
• Test for coeliac disease and hypothyroidism in the ongoing management of intractable constipation
• Consider using a plain abdominal radiograph, transit studies, and USS only if requested by specialist services
• Rectal biopsy for Hirschsprung’s disease if the following present
  • Delayed passage of meconium (more than 48 hours after birth in term babies)
  • Constipation since first few weeks of life
  • Chronic abdominal distension plus vomiting
  • Family history of Hirschsprung’s disease
  • Faltering growth

Management

Acute

• Oral medication regimen for disimpaction if indicated: rectal medications if oral medications failed
• Polyethylene glycol 3350 + electrolytes, using an escalating dose regimen as the first-line
• Add a stimulant laxative if polyethylene glycol 3350 + electrolytes not successful after 2 weeks
• Substitute a stimulant laxative singly or in combination with an osmotic laxative (lactulose) if polyethylene glycol 3350 + electrolytes is not tolerated
• Inform families that disimpaction treatment can initially increase symptoms of soiling and pain
• Do not use and only if the child or young person and their family consent

Maintenance:

• Polyethylene glycol 3350 + electrolytes as the first-line treatment, adding stimulant laxative if not effective

NICE Source: CG99 Constipation in children and young people: diagnosis and management. Summary compiled by Dr D P Sheppard MBBS.