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Nocturnal enuresis in children: Etiology and evaluation

Naiwen D Tu, MD
Laurence S Baskin, MD, FAAP
Anne M Arnhym, CPNP
Section Editors
Jan E Drutz, MD
Carolyn Bridgemohan, MD
Deputy Editor
Mary M Torchia, MD


Urinary incontinence is a common problem in children. At five years of age, 15 percent of children are incompletely continent of urine. Most of these children have isolated nocturnal enuresis (monosymptomatic nocturnal enuresis).

An overview of the causes and evaluation of nocturnal enuresis in children will be presented here. The management of nocturnal enuresis and bladder dysfunction are discussed separately. (See "Nocturnal enuresis in children: Management" and "Etiology and clinical features of bladder dysfunction in children" and "Evaluation and diagnosis of bladder dysfunction in children" and "Management of bladder dysfunction in children".)


The International Children's Continence Society has developed standardized terminology for lower urinary tract function and malfunction in children [1].

Enuresis (synonymous with intermittent nocturnal incontinence) refers to discrete episodes of urinary incontinence during sleep in children ≥5 years of age [1]. Enuresis is divided into monosymptomatic and non-monosymptomatic forms.

Monosymptomatic enuresis is defined as enuresis in children without any other lower urinary tract symptoms and without a history of bladder dysfunction [1]. Monosymptomatic nocturnal enuresis usually is divided into primary and secondary forms. Children who have never achieved a satisfactory period of nighttime dryness have primary enuresis. An estimated 80 percent of children with nocturnal enuresis have this form. Children who develop enuresis after a dry period of at least six months have secondary enuresis [2]. Secondary enuresis often is ascribed to an unusually stressful event (eg, parental divorce, birth of a sibling) at a time of vulnerability in a child's life. Stool retention and suboptimal daytime voiding habits often play a role. However, the exact cause of secondary enuresis may remain unknown.

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Literature review current through: Nov 2017. | This topic last updated: Nov 15, 2017.
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