Enuresis
BASICS
DESCRIPTION
- Primary nocturnal enuresis (NE): 80% cases; never established urinary continence on ≥6 consecutive months.
- Secondary NE: 20% cases; resumption of enuresis after ≥6 months of continence.
- NE: intermittent nocturnal incontinence after expected bladder control age (≥5 years).
- Primary monosymptomatic NE (PMNE): bedwetting without bladder dysfunction or LUT symptoms.
- Nonmonosymptomatic NE (NMNE): bedwetting with LUT symptoms (frequency, urgency, daytime wetting, hesitancy, straining, weak/intermittent stream, post-void dribbling, discomfort, incomplete emptying).
Alert: Adult-onset NE without daytime incontinence warrants full urologic evaluation.
SYSTEMS AFFECTED
- Nervous system, renal/urologic.
SYNONYMS
- Bed-wetting, sleep enuresis, nocturnal incontinence, primary NE.
EPIDEMIOLOGY
INCIDENCE
- Family history dependent.
- Spontaneous resolution: ~15% per year.
PREVALENCE
- 5-7 million children affected in U.S.
- 10% of 7-year-olds; 3% of 11-12-year-olds; 0.5-1.7% at 16-17 years.
- 2-3x more common in males.
- Nocturnal > daytime incontinence ratio 3:1.
GERIATRIC CONSIDERATIONS
- Infrequent; often with daytime incontinence.
ETIOLOGY AND PATHOPHYSIOLOGY
- Interrelated factors: sleep arousal disorder, low nocturnal bladder capacity, nocturnal polyuria.
- Functional and organic causes; many theories without absolute confirmation.
- Detrusor instability.
- Arginine vasopressin (AVP) deficiency or decreased stimulation.
- CNS maturational delay.
- Severe NE linked to bladder overactivity and frequent cortical arousals.
- Organic urologic causes (1-4%): UTI, occult spina bifida, ectopic ureter, lazy bladder, wide bladder neck, posterior urethral valves, neurogenic bladder.
- Organic nonurologic: epilepsy, diabetes mellitus, food allergies, obstructive sleep apnea, chronic renal failure, hyperthyroidism, pinworm infection, sickle cell disease.
- NE occurs during all sleep stages.
GENETICS
- Autosomal dominant inheritance with high penetrance (~90%).
- 1/3 cases sporadic.
- 75% of children have first-degree relative with NE.
- Higher concordance in monozygotic twins (68%) vs dizygotic (36%).
- Both parents affected → 77% child risk; one parent → 44%.
- Parental age of resolution predicts child's NE resolution.
RISK FACTORS
- Family history.
- Emotional/environmental stressors (divorce, death).
- Constipation/encopresis.
- Organic diseases (1% monosymptomatic NE).
- Psychological disorders: depression, anxiety, social phobia, conduct disorder, ADHD (especially ages 9-12).
- Altered mental status, impaired mobility.
COMMONLY ASSOCIATED CONDITIONS
- Obstructive sleep apnea (10-54%).
- Constipation (33-75%).
- Behavioral problems (ADHD in 12-17%).
- Overactive bladder/dysfunctional voiding (up to 41%).
- UTI (18-60%).
DIAGNOSIS
HISTORY
- Lower urinary tract symptoms (LUTS).
- Fluid intake, voiding, stooling patterns (voiding diary).
- Psychosocial history (patient, family, school, bullying).
- Family history of enuresis.
PHYSICAL EXAM
- ENT: adenotonsillar hypertrophy (sleep apnea).
- Abdomen: enlarged bladder, kidneys, fecal masses.
- Back: sacral dimpling, hair tufts.
- GU exam: males (meatal stenosis, hypospadias, phimosis); females (vulvitis, vaginitis, labial adhesions, ureterocele, abuse signs).
- Rectal exam: tone, fecal soiling/impaction.
- Neurologic exam: lower extremities focus.
DIFFERENTIAL DIAGNOSIS
- Primary NE, delayed urinary control, UTI, spina bifida occulta, obstructive sleep apnea, idiopathic detrusor instability, myelopathy, neuropathy, anatomic abnormalities.
- Secondary NE: acute stress, bladder outlet obstruction, neurologic disease.
DIAGNOSTIC TESTS
- Urinalysis mandatory (children).
- Urine culture for infection, hematuria, proteinuria, glycosuria.
- Imaging not usually necessary; consider renal/bladder ultrasound if indicated.
- VCUG, IV pyelogram rarely indicated.
- MRI if spinal dysraphism suspected.
- Urodynamics if daytime symptoms or refractory.
TREATMENT
GENERAL MEASURES
- Nonpharmacologic approaches first line.
- Behavioral: scheduled waking, positive reinforcement, bladder training, diet modification.
- Educate on sleep fragmentation, bladder capacity, urine production.
- Limit fluids 2 hrs before bedtime.
- Encourage voiding before bed, scheduled nighttime voiding.
- Use nightlights, reward systems, pull-ups or waterproof underwear.
- Cleanliness training, avoid shaming or punishment.
- Treat constipation.
- Referral for behavioral counseling if secondary NE suspected.
- Combined therapies (alarms + behavioral + pharmacologic) more effective.
ENURESIS ALARMS
- 66-70% success rate; nightly use 2-4 months.
- Use until 14 dry nights consecutively.
MEDICATION
First Line
- Desmopressin (DDAVP): synthetic vasopressin analogue; decreases nocturnal urine.
- Intranasal (adults only; not recommended in children due to hyponatremia risk).
- Oral: start 0.2 mg at bedtime; titrate to 0.4 mg if needed.
- Effect lasts 8-10 hours; success ~60-70%.
- Side effects: hyponatremia, water intoxication. Restrict evening fluids.
Second Line
- Anticholinergics: not monotherapy in children; screen for constipation/residual urine first.
- Oxybutynin: may increase bladder capacity; success 30-50%.
- Dosage varies by age and formulation; patch options available.
- Other anticholinergics (tolterodine, fesoterodine, solifenacin) used in adults.
- Imipramine: tricyclic antidepressant; anticholinergic and antispasmodic; 40% success; high relapse.
- Monitor ECG before use.
PRECAUTIONS
- Oxybutynin contraindicated in glaucoma, myasthenia gravis, GI/GU obstruction.
- Desmopressin avoided in fluid retention risk.
- Imipramine contraindicated with MAOIs, arrhythmias.
COMBINATION THERAPY
- DDAVP + oxybutynin more effective than alone.
ISSUES FOR REFERRAL
- Persistent NE despite therapies.
- Daytime incontinence or LUT dysfunction.
COMPLEMENTARY & ALTERNATIVE MEDICINE
- Acupuncture has limited supportive data.
ONGOING CARE
FOLLOW-UP
- Behavioral: reassess 1-3 months.
- Alarm: reassess 1-3 weeks.
- DDAVP: reassess 1-2 weeks, then every 3 months.
- Imipramine: reassess 1 month (watch for UTI/constipation).
DIET
- Limit fluid and caffeine 1-2 hrs before sleep.
PATIENT EDUCATION
- Resources: hypnoticworld.com, wetstop.com, dri-sleeper.com, nitetrain-r.com, bedwettingstore.com
- Free bedwetting diary apps: My Dryness Tracker, Bedwetting Tracker, HapPee Time.
PROGNOSIS
- Usually self-limiting in children; 1% persist into adulthood.
- Evaluate for organic causes if adult onset.
COMPLICATIONS
- UTI, perineal excoriation, psychological effects (children).
REFERENCES
- Kuwertz-Bröking E, von Gontard A. Clinical management of nocturnal enuresis. Pediatr Nephrol. 2018;33(7):1145-1154.
- Baird DC, Seehusen DA, Bode DV. Enuresis in children: a case-based approach. Am Fam Physician. 2014;90(8):560-568.
CODES
- ICD10 N39.44 Nocturnal enuresis
- ICD10 R32 Unspecified urinary incontinence
- ICD10 F98.0 Enuresis not due to substance or physiological condition
CLINICAL PEARLS
- Behavioral and lifestyle changes are first-line for primary monosymptomatic NE.
- Enuresis alarms and desmopressin are most effective treatments.
- Secondary enuresis often related to psychosocial factors.