Summary
Enuresis or bed-wetting is the repeated voiding of urine during sleep in an individual with a developmental age ≥ 5 years. In monosymptomatic nocturnal enuresis (MNE), wetting occurs only at night during sleep, while nonmonosymptomatic nocturnal enuresis (NMNE) manifests with daytime urinary symptoms (e.g., daytime incontinence, urinary urgency, difficulty voiding) in addition to nighttime wetting. Enuresis can be primary (nocturnal dryness has never been achieved) or secondary (symptom onset occurs after > 6 months of nocturnal dryness). Primary MNE is typically caused by a mismatch between arousal from sleep and nocturnal urine production and/or storage. Secondary MNE and NMNE are usually caused by psychological stress or medical conditions (e.g., constipation, urinary tract infection). Risk factors for enuresis include psychosocial factors, male sex, and positive family history. The diagnosis is clinical, based on the DSM-5 diagnostic criteria for enuresis. Initial management involves addressing the underlying cause, behavioral modification, use of an enuresis alarm, and/or desmopressin. Children with refractory symptoms or persistent daytime urinary symptoms should be evaluated and managed by a specialist (e.g., pediatric urology). Enuresis has a good prognosis with a high rate of spontaneous resolution.
Definitions
- Enuresis (bed-wetting): repeated voiding of urine during sleep in an individual with a developmental age ≥ 5 years [1][2]
-
Monosymptomatic nocturnal enuresis (MNE): enuresis without daytime lower urinary tract symptoms (LUTS)
- Primary MNE: enuresis in which nocturnal dryness was never achieved
- Secondary MNE: enuresis in which symptom onset is after ≥ 6 months of nocturnal dryness
- Nonmonosymptomatic nocturnal enuresis (NMNE): enuresis and daytime LUTS (e.g., urinary incontinence, urinary urgency, change in voiding frequency, difficulty voiding)
Epidemiology
- Enuresis affects 5–10% of 7-year-olds [2]
- Prevalence decreases with age. [2][3]
- MNE
- NMNE
Epidemiological data refers to the US, unless otherwise specified.
Etiology
There is significant overlap in the etiology of MNE and NMNE. For example, constipation, detrusor overactivity, and psychological conditions can cause MNE (primary or secondary) and NMNE. The most common causes for each type of enuresis are listed below. [2][3]
Primary MNE [2][3]
Primary MNE is caused by a mismatch between arousal from sleep and nocturnal urine production and/or storage. Risk factors include positive family history and male sex. [1]
- Delayed physiological maturation of the brain-bladder axis [4]
- Difficulty arousing from sleep in response to nocturnal bladder cues due to, e.g.:
- High sleep arousal threshold (deep sleeper) [4][5]
- Obstructive sleep apnea (commonly due to adenotonsillar hypertrophy)
- Sleep arousal disorder
-
Nocturnal polyuria due to, e.g.:
- Excess fluid consumption before bedtime
- Osmotic diuresis (e.g., due to consumption of salty or sugary foods at night)
- Insufficient nocturnal vasopressin release
- Low bladder storage capacity
Secondary MNE [1][2][3][5]
Causes of secondary MNE include:
- Psychological stress (e.g., recent move, sexual abuse, family conflicts)
- Underlying pathological conditions, e.g.:
NMNE [2][3]
In addition to conditions that cause secondary MNE, NMNE can be caused by anatomical, neurological, and psychosocial disorders, e.g.:
- Urinary tract disorders
- Chronic kidney disease
- Constipation in children
- Neurodevelopmental disorders; (e.g., attention deficit hyperactivity disorder, autism spectrum disorder, developmental delay) [1][3]
- Psychiatric conditions (e.g., conduct disorder, separation anxiety disorder) [1][2]
Diagnosis
General principles [2][3]
- Enuresis is a clinical diagnosis based on DSM-5 criteria.
- Obtain a comprehensive clinical history (including a 7-day voiding diary if appropriate) and perform a physical examination to: [2][3]
- Consider diagnostic studies for an underlying cause in selected patients.
DSM-5 diagnostic criteria for enuresis [1]
All of the following criteria should be met to confirm the diagnosis.
- Voiding of urine into bed and/or clothing is repeated, involuntary or intentional, and occurs in an individual with a developmental age ≥ 5 years. [1]
- Symptoms occur ≥ 2 times per week for ≥ 3 months or cause significant distress and/or adverse consequences (e.g., social ostracism, poor academic or occupational outcomes).
- Symptoms are not caused by medication or a medical condition.
Evaluate for an underlying cause [2][3]
- Indications for diagnostic testing for an underlying cause include: [2][3]
- Daytime symptoms (i.e., NMNE)
- Secondary MNE
- Daytime LUTS and/or difficulty voiding
- Excessive daytime sleepiness or snoring
- Growth faltering
- Constipation, fecal impaction
- Lower extremity neurological abnormalities
- Sacral anomalies (e.g., sacral tuft or dimple)
- Obtain appropriate diagnostic studies based on clinical presentation, e.g.:
- Urinalysis to assess for UTI
- ENT evaluation for adenotonsillar hypertrophy
- Diagnostics for obstructive sleep apnea
- Diagnostics for chronic kidney disease
- Diagnostic criteria for diabetes mellitus
- Diagnosis of constipation in children
Patients with primary MNE do not routinely require diagnostic evaluation for an underlying cause. [2]
Management
Approach [2][3]
- Address the psychological stressors and/or underlying conditions contributing to enuresis; see, e.g: [2][3]
- Refer patients with NMNE to pediatric urology for management of daytime symptoms and/or LUTS. [2][3]
-
Management of nocturnal symptoms
- Discuss behavioral modification strategies to reduce enuresis.
-
Patients ≥ 6 years and/or those with distress or impaired social functioning due to enuresis: [2];
- Initiate treatment with enuresis alarm or desmopressin; use shared decision-making.
- Consider switching or combining therapies based on symptom improvement.
- Refractory symptoms: Refer to pediatric urology for further evaluation and management.
Treatment of enuresis is not routinely indicated for children < 5 years of age. [1]
An enuresis alarm and desmopressin are both effective first-line management strategies for enuresis. Use shared decision-making to select the appropriate treatment strategy.
Behavioral modification [2][3][6]
-
Behavioral modification strategies to reduce enuresis include:
- Fluid intake regulation (e.g., 30–50 mL/kg per day, minimizing fluid intake 1–2 hours before sleep) [3]
- Timed bladder emptying during the day (e.g., every 3 hours) [3]
- Positive reinforcement of proper voiding techniques
- Discourage use of unproven or punitive measures (e.g., waking the child at night to urinate).
Enuresis alarm [2][3]
A moisture sensor in the child's underwear or sleeping pad triggers an alarm and/or vibration, alerting the child and/or caregiver when involuntary urination occurs.
- Indicated in children ≥ 6 years of age with frequent enuresis [2][3]
- Consistent use without interruption is required.
- Follow-up within 6 weeks.
- Symptom improvement
- Discontinue after 14 consecutive dry nights.
- Treatment may be resumed if symptoms recur.
- No improvement: Consider switching to or combining with other treatment strategies.
- Symptom improvement
Desmopressin [2][3][7]
-
Indicated in children ≥ 6 years:
- With nocturnal polyuria
- When rapid short-term improvement is desired (e.g., school trips)
-
Desmopressin dosage considerations:
- Consider if daily or periodic dosing (e.g., summer camp, sleepovers) is required.
- Desmopressin carries a rare but serious risk for hyponatremia and/or water intoxication. [2][7]
- Withhold desmopressin after periods of increased water ingestion.
- Limit fluid intake to ≤ 200 mL within an hour of bedtime and throughout the night. [2][3]
- Children on continuous treatment: Follow-up every 2 weeks after initiating treatment.
- Improved symptoms
- Consider tapering desmopressin after 3 months of consistent improvement. [3]
- Periodic drug holidays help determine when the medication can be stopped.
- No improvement: Consider switching to or combining with other treatment strategies.
- Improved symptoms
Refractory symptoms [2][3]
Refer children with insufficient response to first-line therapies to pediatric urology for consideration of:
- Additional diagnostic evaluation (e.g., urodynamic studies)
- Alternative pharmacological treatment
- Anticholinergics (e.g., oxybutinin): considered in patients with overactive bladder as a likely cause
- Imipramine: associated with significant adverse effects (e.g., cardiotoxicity, CNS effects)
- Advanced therapies (e.g., peripheral nerve stimulation, intradetrusor botulinum toxin injection)