What causes nocturnal enuresis (bedwetting) in an 8-year-old child?

From the Guidelines

Bedwetting in an 8-year-old is typically a developmental issue that most children outgrow, and the most common causes include delayed maturation of the nervous system, genetic predisposition, smaller bladder capacity, deep sleep patterns, or insufficient production of antidiuretic hormone (ADH) at night. The condition can be managed with behavioral approaches and, if necessary, medication. According to the International Children's Continence Society 1, the main pathogenetic mechanisms involved in monosymptomatic enuresis include nocturnal polyuria, detrusor overactivity, and an increased arousal threshold.

Causes of Bedwetting

• Delayed maturation of the nervous system, which prevents the child from recognizing a full bladder during sleep
• Genetic predisposition, where children are more likely to experience bedwetting if their parents did
• Smaller bladder capacity
• Deep sleep patterns that prevent waking when the bladder is full
• Insufficient production of antidiuretic hormone (ADH) at night, which normally reduces urine production during sleep

Management of Bedwetting

For management, it is recommended to start with behavioral approaches such as:

• Limiting fluids 1-2 hours before bedtime
• Ensuring regular bathroom visits before sleep
• Using a bedwetting alarm
• Implementing a reward system for dry nights If these measures do not help after 3-6 months, consulting a pediatrician is advised, who might recommend medication such as desmopressin (DDAVP), starting at 0.2mg at bedtime for children over 6 years old, as suggested by 1 and 1. This medication mimics ADH to reduce nighttime urine production.

Importance of Supportive Approach

It is crucial to maintain a supportive, non-punitive approach as bedwetting is involuntary and can cause emotional distress for children. Most children naturally outgrow bedwetting by adolescence, but treatment can help manage the condition in the meantime. As noted by 1, the impact of enuresis on affected children is mainly psychological and may be severe, making treatment not only justified but mandatory.

From the Research

Causes of Bedwetting in Children

• Bedwetting, also known as nocturnal enuresis, is a common condition that affects around 15-20% of five year olds and up to 2% of young adults 2
• The exact cause of bedwetting is not fully understood, but it is thought to be related to a combination of factors, including bladder control, hormone regulation, and sleep patterns

Treatment Options for Bedwetting

• Desmopressin, a hormone replacement therapy, has been shown to be effective in reducing bedwetting in children, with a significant reduction in the number of wet nights per week 2, 3
• Alarm therapy, which involves using a device that alerts the child when they start to urinate, has also been shown to be effective in treating bedwetting, with some studies suggesting it may be more effective than desmopressin in the long term 4, 5
• Behavioral therapy, which involves teaching the child to recognize and respond to their body's signals, has also been shown to be effective in treating bedwetting, with a success rate comparable to desmopressin and alarm therapy 6

Factors Affecting Treatment Success

• The success of treatment for bedwetting can depend on a number of factors, including the child's age, motivation, and compliance with the treatment plan 3, 6
• The use of a structured dose reduction strategy when discontinuing desmopressin therapy may help to reduce the risk of relapse 5
• The involvement of parents and caregivers in the treatment process can also play an important role in the success of treatment, with proactive parents and patients more likely to achieve a positive response to alarm therapy 5