Nocturnal Enuresis (Bed Wetting) 

Introduction

Nocturnal enuresis, commonly known as bedwetting, is the involuntary voiding of urine during sleep in children over the age of 5 years, when bladder control is expected to be established. It is a common and often distressing condition for children and their families.

Etiology

  • Primary nocturnal enuresis (most common):
  • No previous period of sustained nighttime dryness.
  • Caused by delayed maturation of bladder control or other functional issues.
  • Secondary nocturnal enuresis:
  • Onset after a period of at least 6 months of dryness.
  • Often associated with psychological stress, infections, or underlying medical conditions.
  • Contributing factors:
  • Genetics: Family history strongly correlates.
  • Polyuria: Excessive nighttime urine production.
  • Reduced bladder capacity.
  • Failure of arousal: Difficulty waking in response to a full bladder.
  • Constipation: Pressure from a distended rectum may impact bladder function.

Epidemiology

  • Prevalence:
  • Affects ~10-15% of 5-year-olds, ~5% of 10-year-olds, and <1% of adolescents.
  • More common in boys.
  • Many children achieve spontaneous resolution by adolescence.

Pathophysiology

  1. Imbalance of bladder function and urine production:
  • Increased nighttime urine production (low nocturnal vasopressin secretion).
  • Reduced bladder capacity or overactive bladder.
  1. Arousal dysfunction:
  • Failure to awaken in response to bladder signals.
  1. Underlying conditions (in secondary enuresis):
  • Urinary tract infections (UTIs).
  • Diabetes mellitus or insipidus.
  • Sleep disorders (e.g., obstructive sleep apnea).

Clinical Manifestations

  • Primary enuresis: Bedwetting without prior consistent nighttime dryness.
  • Secondary enuresis: Recurrence of bedwetting after achieving dryness.
  • Associated symptoms (suggesting underlying conditions):
  • Daytime incontinence or urgency.
  • Dysuria, frequency (suggestive of UTI).
  • Polyuria, polydipsia (diabetes).
  • Snoring or gasping during sleep (sleep apnea).

Diagnosis

  1. History and physical examination:
  • Onset and pattern of enuresis (primary vs. secondary).
  • Urinary and bowel habits.
  • Family history of enuresis.
  • Associated symptoms (e.g., urgency, daytime incontinence).
  • Assess for signs of psychological stress or trauma.
  1. Laboratory tests:
  • Urinalysis: Rule out UTI, glucosuria, or other abnormalities.
  • Blood glucose: Screen for diabetes if polyuria and polydipsia are present.
  1. Imaging and further testing:
  • Renal/bladder ultrasound: Only if structural abnormalities or obstruction are suspected.
  • Urodynamic studies: Rarely needed but may assess bladder function in complex cases.

Treatment

  1. Behavioral Modifications (First-Line):
  • Establish regular bedtime routines.
  • Limit fluid intake in the evening.
  • Encourage regular daytime voiding.
  • Use enuresis alarms to condition arousal to bladder signals (effective for motivated families).
  1. Pharmacologic Treatment:
  • Desmopressin (DDAVP): First-line medication for reducing nocturnal urine production.
  • Effective for short-term use or events (e.g., sleepovers).
  • Imipramine: Tricyclic antidepressant used as second-line therapy but has a higher risk of side effects.
  • Anticholinergics (e.g., oxybutynin): Used in children with overactive bladder or reduced capacity.
  1. Psychological Support:
  • Address anxiety, stress, or self-esteem issues related to bedwetting.

Prognosis

  • Most children experience spontaneous resolution, with a 15% annual resolution rate.
  • Long-term complications are rare but can include psychological stress or social embarrassment if untreated.

SUPERPoint

Nocturnal enuresis is a common condition in children characterized by involuntary nighttime urination. Management includes behavioral therapy, enuresis alarms, and pharmacologic options like desmopressin, with excellent long-term outcomes in most cases.

SUPERFormula

Recurrence of bedwetting after achieving dryness + arousal failure + nighttime bladder signals = Secondary nocturnal enuresis

References

Braddock AL, Taras HL. Children. In: Feldman MD, Christensen JF, Satterfield JM, Laponis R. eds. Behavioral Medicine: A Guide for Clinical Practice, 5e. McGraw-Hill Education; 2019

Sleep and Its Abnormalities. In: Ropper AH, Samuels MA, Klein JP, Prasad S. eds. Adams and Victor’s Principles of Neurology, 12e. McGraw-Hill Education; 2023