Definition

Bed-wetting is involuntary urination during sleep in children over age five. Typically around ages 3 to 5 years, children become able to sleep through the night without wetting. While infection or anatomic abnormalities of the urinary system may explain bed-wetting at night, most cases have no explanation and are referred to by doctors as primary nocturnal enuresis (PNE).

Urinary System in Child

si55551330_96472_1_UTI Children fact sheet
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Causes

When children are sleeping, the bladder may signal the brain that it is full. But the brain must return a signal for the bladder not to empty. Then the child must wake up and go to the bathroom.

Causes of bed-wetting are varied and may overlap. Contributing factors include:

  • Bladder control that develops more slowly than normal
  • Greater than average urine production at night
  • Genetic predisposition
  • A sleep disorder, sometimes related to enlarged tonsils or adenoids

In rare cases, bed-wetting may indicate a physical problem. Usually if a physical problem is responsible, daytime urinary patterns will change as well. Physical conditions that may cause the condition include those in which either excess urine is produced or the bladder does not empty properly:

  • Kidney or bladder infections
  • Kidney disease
  • Diabetes mellitus
  • Diabetes insipidus (a very rare disorder in which sugar is normal but excess water is excreted by the kidney)
  • Congenital bladder, kidney, or neurological abnormality

Unless a child has one of the conditions listed above, virtually all will stop bed-wetting by the time they reach puberty. However, bed-wetting remains a problem for up to 1% of adults.

Closer View of Urinary System

Urinary System
© 2009 Nucleus Medical Media, Inc.

Risk Factors

A risk factor is something that increases your chance of getting a disease or condition.

Risk factors include:

  • Family members with a history of bed-wetting
  • Significant psychosocial stressors, such as:
    • Moving to a new home
    • Loss of a loved one
    • A new baby in the home
    • Initial toilet training that was too stressful
    • Physical or sexual abuse

Symptoms

The child wakes up and finds the bed wet from urine.

Diagnosis

The doctor will ask about symptoms and medical history, and perform a physical exam. Expect to answer questions about:

  • Family history of bed-wetting
  • Daytime urinary patterns
  • Problems urinating, such as pain or weak stream
  • Usual intake of fluids
  • Type of fluids consumed
  • Presence of blood in the urine
  • Strained family dynamics around the issue of bed-wetting
  • Child's emotional response to the behavior
  • Recent psychological trauma

Tests may include:

  • Urine sample—obtained after an overnight fast to determine how concentrated the urine is, and to check for infection and other problems with the urinary tract
  • X-rays or ultrasound study—if, in rare cases, a physical cause is suspected

The doctor may refer you to one or more specialists, such as an ear, nose, and throat doctor if there is evidence of obstructive breathing at night or a psychiatrist if there are significant emotional problems.

Treatment

Treatment for aims to gradually reduce the frequency of bed-wetting until the child essentially grows out of it. Treatment is rarely appropriate before age six, which is usually when bed-wetting begins to interfere with social development.

Motivation and Family Support

Bed-wetting is rarely an intentional act. Children are usually upset and ashamed when it happens. Do not punish the child. It is very important that parents offer encouragement that the bed-wetting will stop with time. Do not let siblings tease the child who wets the bed. Keep careful records of the child's progress and offer consistent support. A very simple motivational method is the use of positive feedback, such as a star chart.

Fluids should be restricted after 6:00-7:00 in the evening, and the child should void before going to bed. Sugar and caffeine should also be avoided after late afternoon.

Behavioral Conditioning

The doctor may recommend a conditioning device, such as a pad with a buzzer that sounds when wet. The child wears the pad in his underwear. The alarm wakes the child to get up and use the toilet. Parents may need to help the child get to the bathroom and reset the alarm.

Most studies suggest that this form of treatment has the highest success rate and the fewest complications. Adding another type of therapy, like dry bed training, can also help your child succeed. Dry bed training involves following a schedule where you awaken your child during the night so he can use the bathroom.

Bladder Training

Some doctors suggest bladder-stretching exercises, but there is little evidence that this approach works. While awake, the child gradually increases the amount of time that elapses between urinations. Do not try this method without talking to the doctor.

Medication

Drugs to treat symptoms include:

  • Desmopressin (DDAVP Nasal Spray, DDAVP Rhinal Tube, DDAVP, DDVP, Minirin, Stimate Nasal Spray)—a hormone available as a nasal spray or in tablet form used to decrease the amount of urine produced
    • According to the Food and Drug Administration, children and adults taking the nasal form of desmopressin are at risk for developing severe hyponatremia. This condition occurs when there are low levels of sodium in the blood, which can result in seizures and death. If you have hyponatremia or a history of it, do not take the nasal spray. Also, if you have an illness that may lead to fluid and/or electrolyte imbalance, do not take the tablet form. Desmopressin should be used with caution if you are at high risk for water intoxication with hyponatremia.
  • Imipramine (Tofranil-PM, Tofranil)—an antidepressant that lightens the level of sleep and may also decrease the frequency of urination
  • Oxybutynin (Ditropan XL, Ditropan, Oxytrol)—an anticholinergic agent that has been used, but has a low response rate

Prevention

Prevention of bed-wetting in children not prone to primary nocturnal enuresis (PNE) is of limited value. Since excess intake of fluid is rarely the cause, restricting fluids prior to bed does not produce consistent results. Still, it is reasonable to have all children empty their bladders prior to bed. Some parents wake their children every few hours to urinate, but most report that they rarely get much cooperation.