Bed-wetting, or nocturnal enuresis, is a common problem for children. Nocturnal enuresis is defined as the involuntary passage of urine during sleep. While it can sometimes indicate an underlying disease, the majority of children are not diagnosed with any etiology. There are two types of bed-wetting: primary and secondary. A child experiencing primary bed-wetting has never been able to achieve bladder control at night. Secondary bed-wetting refers to bed-wetting that starts after a child has been dry at night for at least six months.
Delayed Maturation of the Nervous System
This is an important cause of primary bed-wetting. If the nerves of the bladder are slow to mature, the child cannot sense when the bladder is full, and it may not wake the child from sleep. Therefore, the child will continue to wet the bed at night.
Poor Daytime Toilet Habits
Several children ignore continual urges to urinate during the day. A child can often "hold" his urine for as long as he can, eventually causing bed-wetting at night. A detailed history is important to elicit when and why the child is holding urine. This is a common cause of primary bed-wetting.
Urinary Tract Infection
Urinary tract infections can cause secondary bed-wetting. In children, urinary tract infections can be associated with abdominal pain, fever, urinary frequency and urgency. Oftentimes a urinary tract infection in children can indicate a structural abnormality of the muscles and nerves that control urination. This can present itself as urinary incontinence. A urinalysis and urine culture are usually performed to diagnose a urinary tract infection. Further radiological studies may be needed to look for structural abnormalities.
Diabetes
Bed-wetting may be the first sign of diabetes in a child who has previously been continent at night. High blood glucose causes the body to increase urine output. Other associated symptoms are increased thirst, fatigue and increased appetite. This is a cause of secondary bed-wetting in children.
Chronic Constipation
When a child does not have regular bowel movements, the stool that is backed up in the gastrointestinal tract can push on the bladder, thereby reducing bladder capacity. This can cause secondary bed-wetting in children.
Emotional Problems
Emotional problems are a common cause of secondary bed-wetting. Children experiencing stress at home, parental conflict, starting a new school, experiencing the birth of a new sibling, or being sexually or physically abused can display signs of emotional distress. This can manifest as bed-wetting. A thorough history is required to elicit these underlying issues.
