Bed-wetting in children

How is bed-wetting defined in children?

Bed-wetting is defined as the accidental release of pee during sleep in children who are over the age of 5.
And why does age have to be included in the definition? This is due to the association with the age at which children are expected to have full control over their bladder as well as the age at which medical management is required, see more about this below.

Are there different ‘types’ of bed-wetting?

Okay my friends, try to stay focused.
Bed-wetting is commonly divided into two categories:
Monosymptomatic nocturnal enuresis – this means bed-wetting occurring on its not, without any other signs or symptoms related to the urinary system or function of the bladder.
This type of bed-wetting is further classified into primary monosymptomatic nocturnal enuresis – seen in children who had never had nighttime bladder control for an extended period of time at the time of presentation (and this is the most common type), and secondary monosymptomatic nocturnal enuresis which is seen in children that were able to attain bladder control for a period of at least 6 months and then started experiencing bed-wetting again.

Polysymptomatic nocturnal enuresis – this refers to bed-wetting that is accompanied by signs and symptoms that are related to problems with the urinary system including day-time wetting, urgency, frequency, recurrent urinary tract infections, weak urine flow, obstructed urine flow, dripping at the end of urination, hesitance during urination, the need to apply abdominal pressure or effort to urinate, a sense of lack of bladder emptying, encopresis and so on.

What about day-time wetting (diurnal enuresis)?

Approximately 20% of children who experience bed-wetting during nighttime also complain of problems with their urinary system during the day and may even experience day-time wetting. When day-time wetting is present in addition to nighttime bedwetting, bladder malfunction is commonly considered.

How common is bedwetting in children?

Monosymptomatic nocturnal enuresis is very common in pediatrics and its prevalence is age-dependent.
The condition is seen in about 15% of children aged 5 years, and the prevalence decreases with the age. About 5% of children still experience it at the age of 10 and only a few percent at the age of 12.
The condition is more common in boys than in girls.

What is the cause of nocturnal enuresis?

This is a very complicated question. And if that is how I start my answer, know that it means that we don’t really know the answer and that the cause is multifactorial.
So, before I get started with these factors, it is important to realize that there is a process of maturation that occurs in a child’s bladder function and ability to control urination over the first few years of their life. Note that this complicated process of maturation includes control over bladder function during the day at an early stage, and nighttime control at a later stage, around the age of 5. There are, of course, children that attain control earlier than that, as well.

What are the factors associated with an increased risk of bed-wetting?

A late maturation of the child’s urinary-control mechanisms – I started off by discussing how usually there is a spontaneous resolution of nighttime bed-wetting, as the child grows older. In some children this process is slower. In certain children the process starts at a later stage, after development of the relevant neurological mechanisms within the central nervous system.
Genetics – the condition has a clear familial association. If one of the parents of the child experienced nocturnal enuresis in his/her childhood, their child has a 50% chance of experiencing it. When both parents have had it, the risk increases to about 75%.
Increased urine output during the night – this is due to both an increased intake of fluids before bedtime and a decrease in secretion of antidiuretic hormone. This hormone is secreted by the pituitary gland and acts on the kidney, where it increases the absorption of water and decreases the amount of urine that reaches the bladder.
Sleeping disorders – nocturnal enuresis is associated with deep sleep and difficulty in awakening as a response to the urge for urination. A theoretical association with obstructive sleep apnea, as a result of enlarged adenoids (read more here), for example, has also been proposed in the medical literature, but evidence is not clear-cut.
Changes to the volume and function of the bladder – these are situations where the child’s bladder is smaller in capacity or the muscle is not well synchronized.
Constipation – around 15% of children who have primary monosymptomatic nocturnal enuresis also have constipation. There is both a physiological and emotional association between problems with defecation and urinary control. Read more about constipation here.
Emotional problems – it is difficult to tell whether this causes bedwetting or happens as a result of it. Bedwetting can lead to frustration, embarrassment, and low self-esteem.
Attention-deficit – this is usually one of several factors that may cause polysymptomatic nocturnal enuresis such as congenital anomalies of the kidney and urinary tract, diabetes, pituitary gland disorders, spinal cord disorders, psychogenic excessive fluid intake and so forth.

What are the investigations required for children with nocturnal enuresis?

It is obvious to all of us that the goal of such investigations is to look for, or rule out, a ‘medical’ reason for the bed-wetting. As I already mentioned, the majority of children with the condition do not have a medical problem and therefore minimal investigations are required and they should be individualised depending on the child’s specific complaints. If your child is experiencing bed-wetting it is important to see your primary care physician. I truly believe that all children with nighttime bed-wetting (and even more so if they have daytime wetting or additional symptoms) need to be seen by their primary care physician. Their physician will know how to steer the workup in the right direction.
History of present illness – just like it would for any other medical problem, the investigation starts off with a detailed history of the patient’s past and a more specific history of their present condition. Does the child have nighttime bed-wetting only or does it occur during the day, as well? Are there other accompanying urinary symptoms? How often does the bed-wetting occur? Was there a period when the child had full control of his urine? Does the child tend to hold his urine? Does the child suffer from constipation? Is there a familial history of bedwetting? What are the child’s sleeping habits like?
The physician may ask you to keep a urine diary and note down more information about your child’s drinking and urination habits.
Physical examination – the physician will search for one of the signs associated with bedwetting, such as abdominal distension that may occur as a result of constipation or a bladder that has not emptied fully. A sign of obstructive sleep apnea could be enlarged tonsils or facial characteristics indicative of adenoidal enlargement (read more about adenoid enlargement here). The physicians may also look for signs of congenital defects in the lower back such as an abnormal hair tuft or a deep dimple and sometimes neurological problems in the lower limbs and abnormalities in the genitals. Note that narrowing of the urethral opening in boys is not a reason for bedwetting and you can read more about it here.
Urinalysis – this is performed in order to identify urinary tract infections in acute presentations or in acute exacerbations of a long-standing problem, to assess the concentration of the urine (further investigations are required if the urine is dilute) and to ensure that there are no signs of any kidney malfunction.
Imaging – usually there is no need for imaging studies, not even ultrasounds, in children who have monosymptomatic nocturnal enuresis. Ultrasounds are useful in children with daytime wetting, recurrent urinary tract infections, congenital anomalies in the urinary tract and when bladder function disorders are suspected (to assess bladder wall thickness and ability to empty). The ultrasound can assess for any residual urine in the bladder following emptying. However, as I already mentioned, in most children with monosymptomatic nocturnal enuresis, there is really no need to perform this test.
Additional tests that may be considered are abdominal x-rays to assess for constipation and the presence of a large amount of fecal content, lower spinal cord MRI when a congenital defect is suspected that may lead to malfunction of the bladder and sphincters as a result of neurological damage. Other, less common tests include pyelograms, to assess for congenital anomalies in the urinary tract and urodynamic tests, to assess the storage and release of urine by the bladder and urethra.

When do I need to seek medical attention for investigation and management of bed-wetting?

Truth be told, there is no perfect timing for this and for the most part, you don’t need to rush for medical attention and treatment.
The correct timing varies depending on the child and their family, how much the condition is affecting them and how determined they are to try and resolve it.
Patients are usually encouraged to start treatment after the age of 5, which is the age at which we expect a child to have gained full control over their urination at nighttime. In the past it was common to start treatment at an even older age in boys because the entire ‘maturation’ process was believed to take longer in boys. Since the condition tends to resolve spontaneously with age in the majority of the cases, it is also common to delay treatment even further, especially in older children who experience it at a lower frequency and when the implications of the condition are not significant for the child and their family. There is a high chance that it will resolve spontaneously with time, even without intervention.

How is monosymptomatic nocturnal enuresis medically managed?

There are two main methods of management: behavioural and others, such as conditioning techniques and/or pharmacological medication.
First of all, it is important to identify additional conditions in the child and to manage them simultaneously, as their management will allow better management of the bedwetting. It is important to take signs of constipation and adenoidal enlargement (which can cause obstructive sleep apnea and attention deficits) into consideration. Prior to the start of therapy, it is important to discuss the goals of treatment with the child and parents and what they should expect. There is a difference between the approach to management in a child that wants to be “dry” for camp next week, where we would usually turn to medication with rapid onset, as opposed to a child who needs long-term therapy.
In cases where the bedwetting is secondary to a medical problem, such as congenital anomalies in the urinary tract, management is tailored to meet the medical problem. In this post I will be focusing on treatment of monosymptomatic nocturnal enuresis, even though some of the methods can be used to treat polysymptomatic nocturnal enuresis, as well.
In addition, it is important to realize that the management of bed-wetting is lengthy, often requires a combination of approaches, and may have lots of ups and downs, successes, failures and recurrences.

What is considered successful management?

When it comes to defining successful management of bed-wetting it is important to divide the outcomes into short-term and long-term.
Successful management is defined as 14 consecutive days without any episodes of bed-wetting. Remember that a decrease in frequency of episodes and the ability to reach a greater number of consecutive “dry” nights is also considered an accomplishment, and the medical literature refers to partial success as one where there is a 50-99% decrease in frequency of episodes or symptoms.
When it comes to discussing long-term success, the aim is to reach complete resolution of symptoms, which means no recurrence of episodes for a period of at least 2 years following treatment but even when the response is shorter-lasting, it is still encouraging (see below).

What kind of doctor manages bed-wetting?

It can be either managed by a pediatrician or a family physician. It can also be managed by physicians who have specialised in bed-wetting or by nephrologists or urologists.

What do the available management options include?

The options include a combination of behavioural changes, conditioning therapy and pharmacological treatment.

What kind of behavioural changes are helpful for bed-wetting?

Let me start by emphasizing how important behavioural therapy is when it comes to this condition.
Explain the condition to the child – this includes giving the child and parents an explanation and telling them that the condition is very common and that lots of other children experience it as well (even though many do not share it with others). It is important not to ‘blame’ the child for it, not to make them feel as though they have done anything wrong or make them feel responsible for the challenges it poses on getting ready in the morning, for example. And obviously, it is very important not to punish them for it. Do not punish the child or yourselves!
Avoid holding urine in – it is important to teach the child not to hold their urine in or delay toilet visits, rather to go into the toilet often and to empty their bladder whenever they feel the urge to do so. Sometimes, it is advantageous to teach the child to visit the toilet at regular intervals. For example, during recess or before getting back into class when they are in school. You can also find set times for toilet visits at home, even if the child does not feel like he/she needs to go. This is a good way to adopt structured emptying habits and to teach them to avoid holding their urine.
Avoid eating foods that are high in sugar or salt content and avoid drinking caffeinated drinks – first of all, these types of foods are not healthy and when it comes to bed-wetting, they cause excessive urination as a result of increased water adsorption in the kidneys.
Restrict water intake during the evening hours – minimizing water intake during the evening and avoiding drinking altogether starting 2-3 hours before bedtime is advised. It is still important to make sure that the child is drinking sufficient fluids throughout the day and that this restriction does not cause their total fluid intake per day to decrease.
Empty the bladder out twice before bedtime – this entails taking the child to the toilet for urination prior to bedtime, waiting for a few minutes and then visiting the toilet again. The purpose behind this double toilet visit is to ensure that the bladder is better emptied prior to bedtime. In practice, most children urinate before bath-time and then once again after they are in their pyjamas and ready for bed. It is good to pay another visit right before they go to sleep, after the goodnight kiss.
Motivational therapy – this can be done by gifting the child with prizes for their persistence and cooperation, rather than for keeping dry, as the latter may lead to frustration when the child is unable to reach immediate success. Additionally, they can keep a diary where you can grant them a smiley or star for every dry night that they are able to maintain and you can decide beforehand which presents they are going to get depending on their achievements. It is important that the entire process focuses on positive feedback and that the child is never punished or denied presents for any mishaps.
These behavioural suggestions can be attempted for several months, while allowing for the child to grow and mature at the same time thus possibly reaching spontaneous resolution of the condition. If needed, further therapies can be added at a later stage, but the entire process, including choice of therapy and timing is very individual.

What types of conditional therapies are useful for bed-wetting?

The main conditional therapy is the use of bed-wetting alarms.
How do these alarms work? The alarm has a sensor that recognizes dampness and responds by setting an alarm or vibration that wakes the child up.
How is the alarm used? The alarm is attached to the child’s underwear or bed. It is important to explain to the child what to expect and how to respond to the alarm. The child’s cooperation is vital for successful therapy. As soon as the alarm goes off and the child is awake, they need to go to the toilet to complete emptying of their bladder. Before they return to bed, they are to change their clothes and sheets and reconnect the alarm. If the child does not wake up to the alarm or vibration, the parents need to wake them up and help them go through the process.
The therapy is based on conditioning, that means the alarm that is set off as a response to dampness teaches the child to get up in order to urinate before all the urine has been released. This strengthens the neurological reflex that prevents the bladder from fully contracting and gradually allows for the accumulation of more urine in the bladder.
So why not just wake the child up in the middle of the night and get it over with? For children who wet their bed once a night, waking them up once during the night is an effective method. However, this method does not entail any conditioning which would aid them in making progress and learning how to stop bed-wetting, and therefore this technique is not recommended.
What are the disadvantages to the use of the bed-wetting alarms? The therapeutic effect of using an alarm is not immediate and the process takes a long time. The child needs to experience getting awoken by an alarm or vibration, getting up, and urinating in order for the conditioning to occur. The process requires the child’s cooperation and strong will and may take up to 3-4 months. It is more suitable for younger children and statistically about 30% of families will stop using the alarm mid-way for one reason or another.

What are the available pharmacological therapies?

The first line of treatment is a medication called desmopressin (the second line of treatment is used for resistant or recurrent cases). Desmopressin is actually a substitute for the antidiuretic hormone (ADH) that causes absorption of the urine in the kidney and a decrease in the amount of total urine that eventually reaches the bladder.
There are different formulations of the medication – tablets, sublingual tablets, convenient for younger children who are unable to swallow pills and nasal sprays. The nasal spray, however, is not used for bed-wetting.
How is the drug used? The medication is taken one hour before bedtime. The child is to stop taking in any fluids about 2 hours prior to bedtime, mainly because of the potential side effects of the drug which causes a drop in salts in the blood (hyponatremia). This adverse effect, however, is very rare and there is no need for any special kind of monitoring other than fluid restriction, as mentioned. In addition, if the child is feeling unwell (fever, diarrhea, vomiting, not eating or drinking well), the medication should be stopped temporarily. If headaches appear, a physician should be consulted as this may be the first sign of a drop in sodium in the blood. Again, this is a very rare effect and the medication is generally safe.
If the therapy is successful, the drug is stopped gradually about three months following the start of treatment. Gradual cessation is helpful in preventing recurrence of the symptoms. This is done by slowly decreasing the dose of the drug taken but different methods can be used as well, such as stopping the medication for several consecutive days, increasing the number of days each time. This is guided by the consulting physician. The medication can later be used as single-use for nights when the child wants to be completely safe (such as when going to a sleepover at friends’).
What are the disadvantages to the use of this medication? On the one hand, when it is compared to the bed-wetting alarm, the effect of treatment is quicker and requires less cooperation from the child and their family. However, it is a drug, and just like any other drug is does have its adverse effects and the rate of recurrence after it is stopped is higher than conditional therapy. This medication is also less successful in children who have a problem with bladder capacity and activity.

Is one of the therapeutic options more effective that the others?

This is a good question. As dedicated readers of this website, you already know a thing or two about critical appraisal of medical research. Such studies are difficult to conduct, especially if they are to be done on a large group of people. There are lots of small studies out there that have been grouped and summarized by larger systematic or meta-analyses. And that is when it becomes tricky – you get into having to define which children should be included in these studies (some studies include both children with monosymptomatic nocturnal enuresis and children with polysymptomatic nocturnal enuresis and results will obviously be very different for each of these) and the definition of fully success and partial success.
Generally speaking, in terms of science/research:
It seems like the use of conditioning therapy better than no treatment. This makes sense. But keep in mind that those that do not receive any therapy will also have spontaneous resolution, that is unpredictable. Pharmacological therapy is also better than no therapy. Again, this makes sense. And again, keep in mind the natural history of the condition.
Bed-wetting alarm versus pharmacological therapy – it seems like these are equally effective, but the drug seems to have a greater rate of recurrence.

How is lack-of-response to treatment defined and when is the return of symptoms considered a recurrence following successful therapy?

Less than a 50% improvement in the situation compared to the symptoms prior to the start of proper treatment (3 months of either alarm therapy, medication taken regularly at an adequate dose or a combination of the two), is considered lack of response. Such children need to be referred to bed-wetting clinics and further investigations need to be performed – this is beyond the scope of this chapter.
Return of at least one episode of bed-wetting per month is considered recurrence following successful treatment.

What needs to be done if a child has recurrence of symptoms?

First of all, we need to stop and think about whether a different problem was missed and needs to be managed simultaneously. This is the time to retake the history, perform another physical examination and to consider the need for further investigations. In some of the cases, an underlying problem that has not been addressed may be revealed.
Practically speaking, returning to the technique that was most helpful for the child is advised, be it the bed-wetting alarm or the medication. For the alarm method, children who found it helpful can restart the treatment and it will usually be shorter than the first round of therapy, it is important to ensure adequate dosing and gradual cessation.
The two techniques can also be combined so that the child can possibly gain from both effective treatments.
In other cases, it is possible to move on to the second line of treatment. These are usually prescribed by physicians who are bed-wetting specialists:
Anticholinergic drugs – these exert an effect on the bladders neurological mechanisms and decrease the contraction of the bladder. Some of its side effects include constipation, dry mouth, increased heart rate, palpitations, behavioural changes and even urinary retention.
Tricyclic antidepressants – these act through several mechanisms, exerting an effect both on the central nervous system and on the bladder. They have many different adverse effects, most of which are cardiac.

What about the use of alternative medicine?

Evidence to support the use of alternative therapy for bed-wetting is weak. I propose turning to this option only after having fully understood the real capacity and cost-benefit of such medicine.

What about the use of emotional therapy?

I think emotional therapy can play two very important roles when it comes to treating bed-wetting. Firstly, it is obvious that some of these children have emotional difficulties, and that even if these difficulties are not the main reason behind their bed-wetting, they certainly do contribute to the problem and identification of these difficulties and offering treatment for them can certainly aid the child and their family. Secondly, the bed-wetting itself can cause feelings of deep frustration and a sense of low self-esteem in some of these children and the therapy must include emotional support for the child and their family.

To conclude, this is a long and detailed post about a very common and concerning condition in children. The good news is that it is common and resolves spontaneously in most children, even without intervention. But sometimes, intervention and help are required. I hope this chapter provides you with the information you need to help you choose the best treatment for you and your child. And of-course, remember to choose the right caretaker to help guide you through this journey.