What is the best treatment approach for a patient with a long history of severe constipation, bowel impaction, and associated developmental issues, such as an awkward gait?

Treatment of Chronic Constipation with Fecal Impaction and Developmental Complications

This patient requires immediate disimpaction followed by long-term maintenance therapy with polyethylene glycol (PEG) to prevent recurrence, as chronic untreated constipation from infancy has likely caused both the bowel dysfunction and secondary gait abnormalities.

Immediate Management: Address the Fecal Impaction First

The priority is clearing the existing impaction before any maintenance therapy can be effective.

Digital Rectal Examination and Assessment

• Perform a digital rectal examination to confirm the presence and extent of fecal impaction 1, 2
• Rule out bowel obstruction through physical examination and consider abdominal radiograph given the history of vomiting and distended abdomen 1, 3
• The round, swollen abdomen with history of vomiting strongly suggests significant impaction requiring aggressive intervention 4, 5

Disimpaction Protocol

• Administer glycerin suppository as first-line rectal intervention 1, 3
• If suppositories fail, perform manual disimpaction following premedication with analgesic ± anxiolytic to minimize discomfort 1, 3
• Consider enemas (isotonic saline preferred) if manual disimpaction is insufficient, though use cautiously given the chronic nature and potential for complications 1, 4
• In severe cases, polyethylene glycol solutions via nasogastric tube may be necessary for proximal washout 4

Critical pitfall: Do not start oral laxatives before clearing the impaction, as this can worsen obstruction and increase vomiting risk 5.

Long-Term Maintenance: Prevent Recurrence

After successful disimpaction, the focus shifts to preventing future impactions and establishing regular bowel patterns.

First-Line Maintenance Therapy

Start polyethylene glycol (PEG) 17g once or twice daily as the primary maintenance agent 1, 2, 6, 7. PEG is specifically recommended for:

• Pediatric patients with chronic constipation 1, 2
• Excellent safety profile with minimal risk of dependency 2, 6
• Superior to stimulant laxatives which can cause colonic dependency after prolonged use 2

Alternative or Adjunctive Laxatives

If PEG alone is insufficient:

• Add bisacodyl 10-15 mg daily with goal of one non-forced bowel movement every 1-2 days 1, 3
• Consider senna 2 tablets twice daily as stimulant alternative 3, 8
• Lactulose 30-60 mL twice to four times daily if PEG not tolerated 1, 2

Avoid bulk-forming laxatives (psyllium) in this patient, as they require 8-10 ounces of fluid and adequate mobility, which may be compromised by the gait abnormality 6, 9.

Supportive Non-Pharmacologic Measures

These interventions are essential adjuncts but insufficient alone given the severity and chronicity.

Fluid and Dietary Management

• Increase fluid intake to at least 2 liters daily 2, 6
• Increase dietary fiber only if adequate fluid intake is maintained, as fiber without hydration worsens constipation 1, 6

Toileting and Mobility Optimization

• Ensure easy toilet access given the mobility limitations from gait abnormality 1, 6
• Educate to attempt defecation twice daily, 30 minutes after meals, straining no more than 5 minutes 1, 2
• Use a small footstool to optimize positioning and assist gravity during bowel movements 6
• Encourage increased mobility within physical limitations, even simple movements improve bowel function 6

Abdominal Massage

• Consider abdominal massage, which has evidence for efficacy particularly in patients with neurogenic problems 1, 6
• Given the developmental gait issues potentially indicating neurologic involvement, this may be especially beneficial 1

Addressing the Gait Abnormality

The awkward gait developed during learning to walk is likely a secondary complication of chronic abdominal distention and discomfort during critical developmental periods 10, 11.

• The gait abnormality may improve somewhat with resolution of chronic constipation, but established compensatory movement patterns may persist 10
• Consider physical therapy evaluation once bowel function is stabilized 10
• The neurologic examination should assess for underlying conditions like Hirschsprung's disease (occurs in 1 in 5,000 births) or other congenital causes, though the late presentation makes this less likely 10, 11

Monitoring and Follow-Up

• Goal: one non-forced bowel movement every 1-2 days 1, 3
• Monitor for recurrence of impaction, especially if diarrhea develops (suggests overflow around impaction) 1, 6
• Consider colonoscopy or flexible sigmoidoscopy after resolution to evaluate for anatomic abnormalities 4, 5
• Anorectal physiological testing may reveal abnormalities in rectal sensation, contractility, or sphincter function present in 95% of children with idiopathic constipation 11

Long-term prognosis: With appropriate treatment, 50% of pediatric patients are cured after 1 year and 65-70% after 2 years, though several months to years of supportive intervention may be required 10, 11.