What is the appropriate workup and treatment for nocturnal enuresis (bedwetting) in a 16-year-old?

Workup and Treatment for Nocturnal Enuresis in a 16-Year-Old

The appropriate workup for nocturnal enuresis in a 16-year-old should include a comprehensive evaluation with urinalysis, frequency-volume charting, and assessment for constipation, followed by a structured treatment approach starting with behavioral interventions and progressing to alarm therapy and/or desmopressin if needed. 1, 2

Initial Assessment

• Obtain a detailed history focusing on frequency, pattern, and onset of bedwetting (primary vs. secondary), as well as any daytime symptoms that might indicate non-monosymptomatic enuresis 3
• Complete a 2-week frequency-volume chart or bladder diary to document voiding patterns, fluid intake, and wet/dry nights 3, 2
• Perform urinalysis (mandatory) to rule out infection, diabetes mellitus, or kidney disease 3
• Assess for constipation, as treating it can lead to resolution of urinary symptoms in up to 63% of cases with nocturnal enuresis 2, 4
• Evaluate for sleep disorders, particularly sleep apnea and upper airway obstruction, as these can contribute to enuresis 3, 1
• Physical examination should focus on the lower back and external genitalia to rule out neurological or anatomical abnormalities 3
• Assess family history of enuresis, as there is a strong genetic component 3, 5

Treatment Approach

First-Line Interventions

• Implement behavioral modifications:
  • Regular daytime voiding schedule (morning, at least twice during school, after school, dinner time, and bedtime) 3, 2
  • Evening fluid restriction while ensuring adequate hydration earlier in the day 3, 4
  • Proper voiding posture with relaxed pelvic floor muscles 3, 2
  • Maintain a calendar of dry and wet nights to track progress 3, 6
  • Treat constipation aggressively if present, using polyethylene glycol as needed 3, 2

Second-Line Interventions

• Enuresis alarm therapy:

  • Recommended as the most effective long-term treatment with lower relapse rates 2, 7
  • Provide written instructions and establish a contract to enhance compliance 2, 4
  • Continue for at least 2-3 months before attempting to wean 1, 4
  • Schedule monthly follow-up appointments to sustain motivation 3, 2

• Desmopressin therapy:

  • Particularly effective for children with nocturnal polyuria 1, 4
  • Typical oral dose: 0.2-0.4 mg tablets or 120-240 mg melt formulation taken 1 hour before bedtime 4
  • Limit fluid intake to 200 ml or less in the evening to prevent hyponatremia 2, 4
  • Expect approximately 30% full response and 40% partial response rates 1, 4

For Resistant Cases

• Combine alarm therapy with desmopressin for enhanced efficacy 2, 4
• Consider anticholinergics (oxybutynin, tolterodine) if detrusor overactivity is suspected 2, 4
• Reassess diagnosis and consider referral to a specialist if no improvement occurs after 1-2 months of consistent therapy 2, 4

Important Considerations and Pitfalls

• Avoid punishing or shaming the adolescent, as this can worsen psychological impact 2, 8
• Recognize that untreated enuresis can significantly impair self-esteem and social development 8, 5
• Be aware that 0.5% of adults continue to experience enuresis if left untreated 8
• Excessive fluid intake while on desmopressin increases the risk of hyponatremia 1, 4
• Inadequate duration of treatment before declaring failure can lead to unnecessary changes in therapy 1, 2
• Failing to screen for and treat constipation is a common pitfall 2, 4

For a 16-year-old with persistent enuresis, treatment is particularly important due to the significant social and psychological impact at this age. The approach should be systematic, starting with behavioral interventions and progressing to more intensive therapies if needed, with regular follow-up to maintain motivation and assess response 1, 2, 5.