What is it?
When a child isn't aware that they wet the bed at night while sleeping, it's known as nocturnal enuresis. It may occur every night or just one or two nights a week.
What causes it?
In all children, the development of bladder function control and night-time urine production is a slow process. Few children are dry at night before the age of three, and bed-wetting is quite common up to the age of eight. In most cases there's a delay in the development of the normal pathways of bladder function control within the brain and nervous system, which eventually mature.
There's a large genetic influence, and bed-wetting runs strongly in families. Other contributory factors include anxiety, stress, constipation, urinary tract infection and, occasionally, diabetes or kidney failure.
Daytime enuresis, or loss of bladder control during the day, is less common and when this occurs there's more likely to be a serious underlying problem.
It's more common than people think. One in seven-year-olds, one in five ten-year-olds, and between one in 50 and one in 100 people over the age of 15 (including adults) wet the bed at night.
What are the symptoms?
The person wakes to find the bed is wet - some children find this quite distressing. They may wake as they pass urine or be aware of the sensation of needing to urinate. Any other symptoms, such as pain on passing urine, indicate a possible underlying cause, such as infection.
How's it treated?
Medical treatment is rarely started before the age of seven, but there's plenty the family can try at home. In addition, it may be worth visiting your doctor to rule out any treatable causes. Steps you can take include reassuring the child and explaining it's a common problem, not done consciously and certainly not naughty.
Referral to a continence adviser who can advise on ways to overcome the problem is often recommended.
Don't blame the child or punish them, but take practical steps, such as putting a waterproof sheet on the bed. Star charts can help the child see progress but don't speed up bladder control. An enuresis alarm can help condition the child into getting up at night to pass urine, but one in three children relapse after a few months.
Medical treatments include antidepressants (used for their affect on enuresis not depression) and antidiuretic hormone (known as desmopressin), which concentrates urine at night. They don't cure bed-wetting, but provide temporary relief and are best used on a temporary basis for holidays or sleepovers. Desmopressin can be used on a longer basis if your doctor thinks this might be helpful. In this case it is taken for three months followed by at least a week off to see if symptoms return. This pattern is repeated until symptoms don't return and the child has grown out of the condition. However it doesn't suit every child
In most cases, bed-wetting improves without treatment. If it persists after the age of seven or eight, or if your child starts wetting the bed after at least six months of being dry, you may want to discuss the problem with your doctor.
Information taken from BBC Health
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