It is important to understand the big difference between uncomplicated bed wetting and bed wetting associated with other wetting disorders; i.e., complicated bed wetting.
ATTAINING BLADDER CONTROL
A newborn’s micturition occurs by reflex, voiding at frequent intervals, averaging about 20 times per day.
After 6 months of age, voided volumes increase and the frequency of micturition decreases.
Between 1 and 2 years of age, conscious sensation of bladder fullness develops, setting the stage for voluntary control of voiding.
The ability to void or inhibit voiding voluntarily at any degree of bladder filling commonly develops in the 2nd and 3rd years of life. By age 4, most children have acquired an adult pattern of urinary control.
Normal bladder capacity for each age group can be estimated through bladder capacity in ounces = age in years + 2.
The typical sequence of development of bladder and bowel control has been described as:
- Nocturnal bowel control
- Daytime bowel control
- Daytime control of voiding
- Nocturnal control of voiding
ENURESIS
Nocturnal enuresis refers to nighttime (or sleep) wetting.
About 10% of 6-year-olds still wet the bed routinely (at night or during daytime nap), and in many of those children there is a strong family history of bed wetting. We have treated many teens for bed wetting as well as some adults.
Uncomplicated bed wetting, which occurs in the absence of any other significant daytime voiding problems, headaches, thirst problems or bowel problems, does not deserve evaluation, particularly with a negative urinalysis and no history of urinary tract infections.
Many of these children and their families may simply be given an option of reassurance and/or motivational therapy, conditioning therapy with one of the various alarm systems or pharmacologic therapy through the anti-diuretic hormone DDAVP or the tricyclic antidepressant Imipramine (Tofranil).
The great majority of these children will respond to one or more of these treatments for various lengths of time. It is important to remember that with the drug treatment we are providing symptomatic relief only, and the only way we can find out if the child has outgrown the bed wetting is to stop the medication every 6-12 months and see. If the wetting persists the medication is restarted. Some children may need to be on this medication for several years, as bed wetting in some will not resolve until the late teens and rarely in some much later.
THE CAUSE OF BED WETTING
Enuresis is best viewed as a symptom rather than a disease state and is a manifestation that can be more or less affected by several factors. However, a high percentage of children with bed wetting do not produce normal levels of the urinary concentrating hormone (anti-diuretic hormone ADH) during sleep or a nap.
1. Developmental Delay
A good number of children will mature in time to produce sufficient urinary concentrating hormone at night to prevent bed wetting.
2. Sleep Disorders
A common impression of most parents is that the affected child sleeps unusually deeply. In actual studies, the sleep pattern of enuretics did not differ appreciably from that of normal children. These studies may not completely disprove this association, however.
3. Psychological Factors
Emotional disturbances are rarely, if ever, the primary factor in bed wetting. At best, such disturbances may be present as a manifestation of the child’s frustration at attempting to deal with his/her problem. Therefore, psychological evaluation and/or counseling are almost never indicated as primary treatment.
TREATMENT OF UNCOMPLICATED ENURESIS (Simple bedwetting)
Treatment is tailored in part to the attitudes of the parents and the child who has enuresis, the social structure and the home environment.
Enuresis means nighttime wetting, which may be primary or secondary. Enuresis is predominantly biological, and for the majority there is no place for psychotherapy. Children need to be given time to stop wetting. However, treatment and being dry at night can be socially important and improve self-image.
Investigations
Usually, no investigations apart from urinalysis are necessary. However, in older primary enuretic patients, a renal sonogram may be reassuring.
In those with urinary tract infections and/or daytime frequency/urgency and urge incontinence, a renal sonogram and VCUG can be important. Those with polydipsia/polyuria need to be evaluated for diabetes mellitus, diabetes insipidus and nephrogenic diabetes by checking for glucosuria and the urinary specific gravity, etc.
Those with constipation or other bowel dysfunction require additional evaluation.
Specific treatment should be addressed when wetting becomes a problem to the patient and/or family but is rarely necessary before the age of 6, as spontaneous resolution is still common before 6.
Withholding fluids in the evening and/or random awakening of the child to void rarely work, but if they do it may be reasonable to continue in this way. Punishment is not helpful. Food sensitivities and allergies are not factors in bed wetting.
1. DRUG TREATMENT
Today, in uncomplicated bed wetting, DDAVP as the nasal spray or the pill is routinely used as the first line of treatment in those over 6 years of age. If this drug proves unsuccessful, it can be replaced with Tofranil. DDAVP is now considered first line treatment because of the immediate response and because it is less labor intensive than other treatments. Sedatives or stimulants appear to be of no success.
A. DDAVP
This is an antidiuretic hormone (concentrates urine), a medication that is quite successful but quite expensive. This medication is given at bedtime and brings about concentration of the nighttime urine output, resulting in a smaller volume of urine and so allowing the child to store this volume rather than having to expel a large dilute volume of urine and wet the bed. The response to the DDAVP is somewhat dose-related. Rarely, children may complain of headaches and/or nausea.
This medication should be taken for a 6-12 month time span before seeing if the child’s wetting has spontaneously resolved. If the child continues to wet the bed after a trial stoppage of the medication, the DDAVP should simply be restarted. This medication can be used lifelong, if necessary.
B. Tricyclic antidepressants.
The exact mechanism of action of Imipramine (Tofranil), a tricyclic antidepressant, in enuresis is not well understood. The dosage taken is commonly between 25 and 75 mg, usually on a weight basis. Some patients who do not respond completely may still note significant improvement.
Mild side effects are fairly common, including drowsiness, dry mouth, nausea and sometimes some behavior problems. A potential concern is overdosage of this medication, leading to cardiac arrhythmias.
Like the DDAVP, this medication should be prescribed for 6-12 monthly runs before a trial stoppage to see if there has been spontaneous resolution. If bed wetting returns, the medication can simply be restarted. It is important to underscore the fact that these medications do not cure enuresis, they simply provide symptomatic relief until the child himself or herself outgrows the problem.
2. BEHAVIOR MODIFICATION
(Does not mean psychological counseling)
A. Motivational therapy
It promotes development of a positive relationship in providing positive reinforcement ranging from words of praise to an award system.
B. Conditioning therapy
It centers around the use of a signal alarm that is triggered by contact with urine when the child voids.
It is important to underscore the fact that unless the parents help the child to awaken for some period of time (often with the aid of something like a cold, wet flannel to the face), most alarm systems will not be of benefit. The child simply sleeps through while everybody else in the house wakes up to the alarm.
Numerous alarm systems are available, such as Wet Stop, Nytone Enuretic Alarm, Night Trainer Enuresis Alarm, and a vibrating system, Potty Pager.
Although these systems can have a high rate of success after several months of treatment, relapse occurs in at least 1/3 of these patients after conditioning therapy. Retreatment, however, will often lead to success.