Enuresis (bed wetting)

Definition:
Involuntary urination during sleep ≥2 times/week for ≥3 months in children >5 years old.

• Developmental Norm:
  • Night-time continence is a normal developmental milestone with wide variability.
  • Daytime bladder control by ~4 years; night-time control expected by 5–7 years.
• Prevalence:
  • ~30% of 4-year-olds wet the bed.
  • ~10% of 6-year-olds continue to experience enuresis.
• Natural Course:
  • High rate of spontaneous resolution.
  • Treatment usually not initiated before 6 years due to this.
• Psychosocial Impact:
  • Generally no underlying physical/emotional pathology.
  • Can cause embarrassment, shame, reduced self-esteem, especially with age.
  • Problematic mainly when it interferes with social activities (e.g., sleepovers, school camps).
• Treatment Indications:
  • Not required if enuresis is infrequent or not distressing to child/parents.
  • Consider treatment if it impacts psychosocial functioning.
• Risk Factors:
  • Strong genetic predisposition (often familial).

types

• Primary: Child hasn’t been dry for at least 6 months
• Secondary: Onset after 6 months of dryness.
• Monosymptomatic: Nocturnal wetting without daytime incontinence
• Non-monosymptomatic: Correlated with daytime symptoms.

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Epidemiology:

• Prevalence similar across cultures, varies with age:
  • 15% at age 7
  • 10% at age 10
  • 2% in adolescents
  • 0.5 to 1% of adults
• More common in boys (3:1 ratio), but ratio decreases with age
• Additionally, 20 to 30% of patients with enuresis also suffer from at least one psychological, behavioural, or psychiatric disorder, a rate twice as high as that of the general population.
• The most common of these comorbidities is attention deficit and hyperactivity disorder
• Other comorbid conditions in this category include autism spectrum disorder, oppositional defiant disorder, and mood disorders

Associated Conditions:

• Constipation
• Urethral obstruction
• Ectopic ureter
• Cystitis
• Diabetes insipidus
• Disorders of sleep arousal
• Small bladder capacity
• Overactive bladder

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Pathophysiology:

• genetic component
  • studies suggest that inheritance of the condition is in an autosomal dominant pattern with 90% penetrance
• Nocturnal Polyuria:
  • Associated with vasopressin deficiency or circadian release alterations.
  • Leads to increased urine production at night.
• Bladder Dysfunction:
  • More common in patients with daytime incontinence.
  • Manifests as:
    • Diminished bladder capacities.
    • Abnormal urodynamics.
    • Nocturnal detrusor hyperactivity.
  • Can be linked to constipation, causing bladder distortion.
• High Arousal Thresholds:
  • Difficulty waking up due to:
    • Disturbed sleep (e.g., obstructed airway).
    • Contractions in the bladder.
  • Can be a cause or result of enuresis.
• Maturational Delay Hypothesis:
  • Supported by:
    • Higher prevalence of motor clumsiness.
    • Perceptual dysfunction.
    • Speech disturbances in children with enuresis.

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History

Much of the history should focus on voiding habits

• Onset of bedwetting
  • if acute — last few days to weeks — consider whether this is a presentation of systemic illness
• Has the child previously been dry at night without assistance for 6 months?
  • If so, consider possible medical, emotional, or physical triggers
  • The presence of unexplained persistent secondary enuresis despite adequate management should prompt specialist referral
• Presence of day-time symptoms
  • frequency, urgency, polyuria, dysuria/recurrent UTI, poor urinary stream/straining, leakage)
  • If daytime symptoms predominate, consider treating before bedwetting
• Bedwetting pattern and trend
  • nights per week/month
  • amount
  • time of night
  • arousal from sleep
• Fluid intake
  • evening fluid intake
  • caffeine containing drinks
  • polydipsia
• Bowel habit
  • constipation/soiling
• Sleeping arrangements and routine
  • including own bed/bedroom
  • snoring and disturbed sleep
• Medical History:
  • consider other co-morbid factors which may exacerbate or prolong nocturnal enuresis;
  • developmental or behavioural problems
  • diabetes mellitus
  • sleep apnoea 
• Family history of bedwetting or renal problems
• Social history;
  • family capacity and motivation to engage in treatment
  • social difficulties (vulnerable child/family)
• Development history
  • Patients should have screening for psychological or behavioral disturbances, including attention deficit and hyperactivity disorder and learning disabilities, and obtaining a developmental history is also necessary

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Examination

• Height, weight, BP — poor growth / loss of weight / hypertension
• Abdomen — distended bladder, faecal mass
• Inspection of external genitalia (and perianal area if constipation also present) 
• Lower Back/Spine – exclude occult spinal dysraphism or tethered cord (asymmetric/deviation of gluteal cleft) 
• Assessment of lower limb neurology

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Evaluation:

• AS PER RCH GUIDELINES:
  • Dipstick urinalysis is not required in primary enuresis.
  • Consider if red flags apparent.
  • Further imaging or blood tests are not routinely recommended in enuresis
• Urinalysis MAY SHOW:
  • alterations in specific gravity in diabetes insipidus
  • glycosuria in case of diabetes mellitus
  • presence of nitrites leukocyte esterase, leukocytes, or bacteria in case of infection

General Advice

• Treat constipation first if present – essential before enuresis management.
• Educate on normal bladder physiology and the genetic nature of enuresis.
• Reassure:
  • Very common in peers.
  • Not the child’s fault – no shame or embarrassment warranted.
• Encourage:
  • Regular fluid intake and scheduled toileting, especially during school breaks and before bed.
• Avoid:
  • Fluid restriction (not helpful).
  • Caffeine or stimulant drinks in the evening.
• Motivation:
  • Both parent and child must be ready before starting behavioural treatment.

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Bedwetting Alarms (Pad and Bell Alarms)

• First-line treatment:
  • Best long-term success; lower relapse than pharmacotherapy.
• Requires:
  • Supportive home environment.
  • Clear communication that it can take 6–8 weeks to show benefit.
• Age:
  • Generally used in 6–7+ years (if mature, motivated, and physically able).
• Considerations:
  • Mild-moderate intellectual disability → not a contraindication.
  • Hearing-impaired → use vibrating alarm.
• Contraindications:
  • Emotionally overwhelmed carers, anger/blame towards child, or inability to manage sleep disruption.
• Child’s role:
  • Must be actively involved.
  • Ideally, child should wake and walk to toilet independently.
• Rewards:
  • Focus on behaviours (e.g. responding to alarm), not on dry nights.
• Monitoring:
  • Continue if early improvement by 4 weeks → continue until 14 consecutive dry nights.
  • Stop if no early improvement after 4 weeks.
  • If partial response after 3 months → review appropriateness or trial again in 3–6 months.

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Overlearning Technique

• Used after achieving dryness for 2+ weeks.
• Purpose: reinforce bladder control to reduce relapse.
• Method: Extra fluid intake in hour before bedtime to challenge continence.

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Other Behavioural Strategies

• Lifting (carrying child to toilet asleep):
  • Not effective for long-term dryness.
• Waking & walking child:
  • Provides short-term control only.
  • May be useful if self-initiated using phone/alarm clock.

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Pharmacological Therapy

Tricyclics (e.g., imipramine):

• Not recommended
• Less effective and associated with higher risk of adverse effects (e.g. cardiac toxicity, seizures)

Desmopressin (Minirin™ melt/tablet)

Indications

• Alarm therapy has failed or is unsuitable
• Short-term or rapid improvement required (e.g., sleepovers, camps)
• Use with caution in children <7 years — assess maturational readiness
• High relapse rate on cessation (60–70%)

Administration Considerations

• Strict fluid restriction:
  • No fluid from 1 hour before dose to at least 8 hours after
  • Contraindicated in children unable to adhere to fluid restriction
• Assess efficacy after 4 weeks
  • Stop if no benefit
• Trial withdrawal:
  • Cease for 1 week every 3 months to assess for need/relapse

Dosing

• Sublingual (Melt) – >6 years:
  • Start: 120 micrograms at bedtime
  • If needed, increase to 240 micrograms after 1–2 weeks
• Oral tablet – >6 years:
  • Start: 200 micrograms at bedtime
  • If needed, increase to 400 micrograms
• Intranasal:
  • Not recommended due to higher risk of hyponatraemia

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Prognosis

• Spontaneous resolution common with age
• However, may be associated with:
  • Emotional or physical abuse
  • Low self-esteem
  • Poor academic performance

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Complications of Untreated Enuresis

• Quality of life significantly impacted
• Psychological burden:
  • Social withdrawal
  • Low self-esteem
  • Anxiety, stress, and mood disturbances
• Effective management improves social functioning and mental health

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Consider referral to a general paediatrician or continence service when

• Red flags are present
• Persistent enuresis with failure of an enuresis alarm
• Day-time enuresis or combined day/night enuresis after exclusion or treatment of a UTI and constipation
• History of recurrent urinary tract infections
• Comorbidities such as type 1 diabetes, physical or neurological problems
• Substantial psychological or behavioural problems (consider mental health referral, paediatrician and/or child protection services if significant concern exists)

Behavioural Interventions for Bedwetting (Enuresis)

from https://www.racgp.org.au/clinical-resources/clinical-guidelines/handi/a-z/b/behavioural-interventions-including-alarms-bedwett

Indications

• Affects ~15–20% of 5-year-olds.
• Higher risk if parents had enuresis.
• Treat only if distressing to child or family.
• Night-time control not expected until age 5–7.
• Treatment not required if child is unconcerned and no impact on social function.

Simple Behavioural Interventions

Overview

• First-line approach; low effort, no side effects.
• Suitable for most children early in management.

Types

• Lifting: Carry sleeping child to toilet without waking.
• Waking: Wake child at set/random times to void.
• Reward charts: Visual reinforcement for dry nights.
• Retention control training: Delay urination once/day to increase bladder capacity.
• Bedwetting alarms: Effective, usually reserved for age ≥7.
• Overlearning: After dry period, increase fluid intake before sleep while using alarm.

Bedwetting Alarms

Mechanism

• Sensor detects first urine drops → triggers alarm (sound/light/vibration).
• Teaches child to wake or stop voiding.

Use Protocol

• Suitable from age 7+.
• Child should take ownership of alarm.
• Parents support with positive reinforcement.
• Initially may need parental waking assistance.
• Goal: 3–4 consecutive dry weeks.
• Usual duration: 3–4 months (range 5 weeks–6 months).
• May restart if relapse occurs.

Overlearning Technique

• Once dry, child drinks ~200 mL water before bed.
• Continue alarm use to challenge bladder control.

Complex Behavioural Interventions Overview

• More effort-intensive.
• No additional benefit over alarm alone.

Types

• Dry bed training:
  • Night 1: Hourly waking until 1am.
  • Nights 2–6: Wake once, progressively earlier each night.
  • Night 7: Child wakes independently.
  • Restart if wetting occurs on 3 nights.
• Full-spectrum home training:
  • Combines dry bed training, overlearning, bladder training, and child-led sheet changes.

Precautions

• Rule out constipation, UTI, and diabetes if clinically indicated.

Adverse Effects / Challenges

• Sleep disruption for child and parents.
• Frustration with slow response or relapse.
• Requires high motivation and readiness from both child and parent.
• Delay therapy until child is developmentally and emotionally ready.

Availability of Alarms

• Available for purchase ($80–160) online in Australia.
• Available for hire from children’s hospitals (e.g., Royal Children’s Hospital) with paediatrician referral.

When to Refer

• Persistent enuresis despite home interventions.
• Referral to paediatric enuresis clinics in major tertiary centres.