Treatment of Faecal Soiling Due to Constipation with Overflow Incontinence in a 12-Year-Old
The recommended treatment for this 12-year-old with faecal soiling from constipation with overflow incontinence is polyethylene glycol (PEG/Movicol) as the primary laxative, combined with lactulose, dietary modifications, and a structured toileting program, with treatment continuing for months after symptom resolution to prevent relapse. 1
Initial Management Approach
Disimpaction Phase
- Begin with high-dose polyethylene glycol for the first few days to achieve fecal disimpaction, as this is the essential first step when overflow incontinence is present 2
- The Movicol 1 sachet daily prescribed is appropriate for maintenance but may need escalation initially for disimpaction 2
- Lactulose 5-20ml twice daily serves as an adjunctive osmotic laxative, with pediatric dosing for adolescents typically 40-90ml total daily dose divided 3
Maintenance Therapy
- Polyethylene glycol has demonstrated superior efficacy compared to other laxatives and should be the cornerstone of treatment 1
- The combination of PEG with lactulose provides dual osmotic action, though PEG alone is often sufficient 1, 2
- Treatment must continue for at least 6 months to 2 years after symptom improvement to prevent relapse 4
Non-Pharmacological Interventions
Dietary Modifications
- Increase dietary fiber to 25g/day with adequate fluid intake 5
- High-fiber foods including kiwi fruit and apple with skin are appropriate recommendations 5
- Avoid excessive salt and protein restriction, as this can compromise growth in adolescents 6
Toileting Program
- Establish a regular toileting routine with the child sitting on the toilet each morning after breakfast to utilize the gastrocolic reflex 4
- Ensure proper toileting habits and privacy, which is particularly important for adolescents 5
- Education regarding toilet adaptation and daily bowel movements helps restore colonic motility 2
Lifestyle Measures
- Encourage appropriate exercise and maintain an active lifestyle 5
- Adequate fluid intake is essential as an adjunctive measure 5
Family Education and Support
Critical Counseling Points
- Explain that overflow incontinence is involuntary and not intentional—the child should never be punished 7
- Educate parents about the pathophysiology: hard stool impaction causes liquid stool to leak around the blockage 7
- Reassure that this is a common, treatable condition requiring long-term compliance 7, 4
Monitoring and Follow-up
- Treatment success requires months of therapy even after symptoms improve, as premature discontinuation leads to relapse 4, 2
- Monitor for treatment efficacy through symptom diaries, frequency of soiling episodes, and stool consistency 4
- Return if no improvement occurs or if abdominal pain develops 5
When to Escalate Treatment
Second-Line Options
- If constipation persists despite PEG and lactulose, consider adding bisacodyl suppository, magnesium hydroxide, or adjusting PEG dosage 5
- Glycerin suppositories can be used for acute episodes lasting several days 5
- In severe refractory cases (approximately 17% of patients), more invasive interventions like transanal colonic irrigation may be considered before surgical options 8
Important Caveats
Treatment Duration
- The most common pitfall is discontinuing treatment too early—maintenance therapy must continue for months after clinical improvement 4, 2
- Many families expect rapid resolution, but successful treatment requires sustained compliance over 6 months to 2 years 4
Dosing Considerations
- If diarrhea develops with lactulose, reduce the dose immediately and consider discontinuation if it persists 3
- PEG dosing may need adjustment based on response, with the goal of producing 2-3 soft stools daily 1, 3