PE23.2 | Constipation — Summary & Reflection

KEY TAKEAWAYS

Constipation in children is common and mostly functional, but Hirschsprung's disease must always be considered and excluded in neonates.

• Define functionally using ROME IV: ≤2 stools/week + one or more of: hard/painful stools, withholding behaviour, soiling/encopresis, rectal fecal mass — for ≥1 month

• Red flags for organic cause (especially Hirschsprung's): Delayed meconium >48h at birth; onset in first month of life; absent soiling; empty rectum on examination in the setting of obstruction; poor growth; neurological signs; ribbon stools

• Hirschsprung's disease: Aganglionosis of myenteric + submucosal plexuses → spastic non-relaxing segment → obstruction → megacolon proximal; confirmed by rectal biopsy (absence of ganglion cells); contrast enema shows transition zone; RAIR absent on manometry; treatment is surgical pull-through

• Functional constipation management (step-wise):
1. Educate parents — soiling is involuntary overflow, not misbehaviour
2. Disimpact first: PEG 1–1.5 g/kg/day × 3–6 days
3. Maintenance: PEG 0.4–0.8 g/kg/day for ≥6 months
4. Dietary: increase fibre, adequate fluids, reduce excess cow's milk
5. Toilet training: scheduled post-meal sits, footstool, reward chart

• Never start maintenance on a loaded rectum — always disimpact first

REFLECT

A mother brings her 6-year-old for the third time in 6 months with 'accidents' at school. She says she is considering stopping the 'laxative experiment' because it is not working. You examine the child and find a loaded rectum — the disimpaction was clearly inadequate.

Reflect on how you would explain to this mother: (1) why the maintenance laxative appeared to 'fail' — what the underlying mechanical reason was; (2) why her son is not soiling deliberately; and (3) why treatment needs to continue for many more months. How would you rebuild her confidence in the treatment plan? What communication skills are needed alongside the clinical knowledge to manage functional constipation effectively?