Patient Education
Nocturnal enuresis is a common but very controversial topic. The incidence of NE is about 15% in 5 year olds and goes down to 10 % by age of 7 years. However, this is a significant number going by the number of children that there are in India. These being western incidence, we do not have a proper survey to show the actual incidence in India it may be more or may be less too. The problems with this condition are multiple like is it physiological? Should we be treating it? Who is best suited to treat it? What if we just wait and watch and as the child grows, it may go away? This is based on the incidence of spontaneous resolution of 15% per year. All the answers may not be satisfactory but we can go by research done already that gives us a lot of pinters as to how we should proceed.
Nocturnal enuresis is the inappropriate voiding (emptying) of the bladder at an inappropriate time or place by a child over 5 years old. Enuresis differs from incontinence where only a few drops or milliliters of urine are spilled. To get a better idea of how to approach this condition it would be nice to classify the same. Nocturnal enuresis can be classified as Primary: when the child has always being wetting the bed and continues to do so beyond the age of 5 years. Secondary or Onset NE is defined as a child who has been continuously dry for at least 6 months who then begins to bedwet. This type of secondary bedwetting I commonly due to a psychological cause like: separation from parents, fight in the home, separation of the parents, new school, new strict master etc. These children require a lot of counseling from a good psychiatrist.
Primary NE can now be further classified into Monosymptomatic Primary NE where the only complaint s bedwetting at night and no other symptoms. However, there may be a few children who may have other daytime voiding symptoms like frequency, urgency, wetness, hesitancy, straining to pas urine etc. These are classified as Nonmonosymptomatic Primary NE.
The importance of the classification is because the approach to treating children will be a little different in both these types.
Why should we be treating NE? Answer is simple, it affects the child as well as it affects the parents and hence the need for treating the condition as well as the family!!! Children become scared of being discovered by their cousins, classmates of being a wetter, they are likely to be teased, bullied, beaten etc. Also they are scared of going to stay overnight for picnics from school or to their cousins place during vacations due to the fear of wetting the bed and being discovered to be bedwetters. Some children become quiet, isolated, introvert and may go into anxiety and if not treated into depression. The parents too do not realize that NO child wets the bed on purpose, all children want it to stop. The parents feel that the child is doing this either because he/she is defiant, lazy, stubborn or to draw attention towards self. This may lead to the parents getting irritated, angry and ultimately punitive and are known to have beaten up the child. This is the worst thing that they have done and had they been counseled this would not have occurred. They have to be educated and made aware of facts together with their child.
The causes for bedwetting are multiple and basically it is due to a mismatch between the urinary volume produced, the capacity of the bladder to hold urine and the arousal from sleep to voluntarily pass urine. There is a genetic background to bedwetting that must be kept in mind, the chances of being a bedwetter in a child who’s both parents have been bedwetters is 77%, the chances are 44% if any one parent had been a bedwetter. Also, there may be a lag in normal maturation of the bladder and continence mechanism and could lead to bedwetting. Allergy to certain foodstuffs may make the bladder irritable and lead o bedwetting. Lastly, constipation if present, can also cause bedwetting in a child and treatment of the constipation may cure the bedwetting.
Thus, in short the problems could be one or more of the following:
Urinary volume – produced by kidneys
Bladder problems
Sleep arousal & obstructive sleep apnea
Sine this is a basic article I shall not be going into too much detail of the causes and mechanisms, but suffice it to say that urinary volume is dependent on the circadian secretion of the Anti-Diuretic Hormone (ADH) by the body, as suggested by the name the action is to decrease the volume of urine produced at night. The volume of urine produced during 8 hours of sleep in a child is less than 50% of the volume produced during the day and hence the bladder does not get filled and thus will not be emptied. However, in many enuretics, this ADH has been found to be deficient and therefore the urinary volume is like daytime, a large volume that fills the bladder and hence is passed by the child in sleep.
As far as the bladder is concerned, the normal growing bladder keeps increasing its functional capacity with age and the rough calculation is Age + 2 X 30 in ML is the capacity expected at that age. Thus an 8 yr old should have a capacity of 300 ml. In some enuretics this capacity may be less than normal and hence bladder can get filled up and will empty if the capacity is exceeded. Also, the bladder muscle – detrusor normally relaxes while the bladder is filling up with urine, and is voluntarily contracted by the child when he/she wishes to pass urine, simultaneously the urethral sphincter and bladder neck relax to allow urine to be emptied outside. In 30% of enuretics, this detrusor may be irritable and “overactive” leading to involuntary contractions during the sleep and this leads to emptying of the bladder and bedwetting. Now you can imagine what will be the result if, in a given child there is a deficiency of ADH and a small bladder capacity, or if the bladder detrusor is contracting more than normal.
Lastly, sleep arousal is also a problem in more than one way. Some children are deep sleepers and the parents will tell you that they are very difficult to wake up and hence they do not get the sensation of bladder being full in their sleep and will empty their bladder while asleep. Again, if you combine the above reasons along with sleep arousal problems just think of what may happen. In some children, there may also be sleep disordered breathing leading to obstruction of the airway that ultimately leads to Obstructive Sleep Apnea (OSA). This OSA by itself can lead to ineffective secretion of ADH leading to large volume of urine and one again bedwetting.
Then comes the controversy as to who should be treating these children with bedwetting – a pediatrician, a pediatric surgeon, an urologist, a psychiatrist, or all of the above?? The right answer would be any doctor who has the Time, Interest and Knowledge about the subject would be ideal to treat these children. This is not a simple treatment, it takes months of therapy, motivation by the treating doctor to both the child and the parents to cooperate, be compliant, follow all instructions meticulously and follow up regularly as and when asked to.
The approach to a child with bedwetting requires a detailed history to rule out the above mentioned possible etiologies, and hence I have a questionnaire that I have devised that contains over 50 questions that have to be answered by the parents and the child. Base on the answers, they are then analyzed to come to a conclusion as to what are the possibilities in this particular child leading to bedwetting and therefore the treatment will have to be directed towards those causes. I also ask for a Bladder Diary: that is charting for about 4-6 days of Frequency and volume of urination by the child, which may give me some idea of overactive bladder and bladder capacity together with the history. A thorough examination of the abdomen, the back and the external genitalia of the child needs to be done to rule out actual other causes for the enuresis and rule out neurogenic bladder and local causes.
In most cases basic investigations like Urine for sugar, osmolality and pus cells along with the bladder diary can give a lot of information to start therapy. Rarely in select cases, an Ultrasound of Kidneys Ureters, Bladder may be required as well as in even fewer cases Urodynamic studies, or Sleep studies etc. This is why history taking is time consuming but vitally important.
Coming to the actual treatment for this condition, as I said first classify the type of NE, if Primary is it Monosymptomatic or Non Monosymptomatic – then first treat the symptoms during daytime that the child complains of as per regular method and once the symptoms of daytime are under control then go for therapy for NE. If the child has constipation treat that aggressively get in under control, check if the NE is less, or has disappeared, if still there start therapy. If there is specific problem like sleep apnea – treat the same. If it is Secondary? Onset type of NE then probably a psychiatrist/psychologist, counselor would be the correct person for the child to be referred to for further therapy.
Therapy for PMNE can be divided into 3 parts
General measures or Behavior modification
Bladder conditioning or Enuresis alarm
Pharmacotherapy.
General measures are like controlling intake of fluids in evening, double micturition at bedtime, avoiding caffeine, etc.
Bladder conditioning by use of alarm which is fitted to the child and passing minimal urine will cause the alarm to trigger and wake the child up who will than stop urinating, gets up and goes to the bathroom to pass urine, comes back and sleeps. The alternative is to wake the child at fixed time of the night by bedside alarm, take him/her to the bathroom to pass urine and come back and sleep. This is done only once at night. Use of alarm into which I cannot go into in this article has advantages and disadvantages and needs to be used on a regular basis every night for months to get good results
Pharmacotherapy is divided into 3 groups of drugs
Desmopressin is an analogue of ADH or Vasopressin without its vascular effect. This drug acts like ADH and decreases the volume of urine by night and hence is to be given n hour before bed. This works well if the child has a bladder capacity near to the expected capacity for that age. This needs to be titrated until we get dry nights and then maintained for - 8 weeks before gradually decreasing the dose. In some children Alarm and Desmopressin need to be used together and have been shown to give better results than either alone. Desmopresin in NE is accepted as Clinical Evidence type 1 A in Evidence based medicine and has been shown to have few side effects –provided all instructions about fluid intake have been given properly and followed regularly
Anticholinergics is the other group of drugs used in those children who either have a low bladder capacity or have an overactive detrusor of the bladder. Again, in some cases with overlapping causes it may be required to use a combination of Desmopressin and Anticholinergics for better results in particular children
Imipramine: has been used in the past, however, no one knows exactly how it works though results have been there, but currently it is not a drug of choice as per recommendations by FDA and other Societies for Incontinence. This drug is used more for its side effects than its effect, hence to get a therapeutic result, a higher dose needs to be given. There have been reports of overdose with cardio toxicity. In the western world no one uses this drug. This is Grade 1C level of evidence as per ICI, ESPU etc. guidelines.
I think this, in short is an overview of Nocturnal Enuresis and its approach. I hope this has cleared up some ideas as to why it cannot be allowed to decrease on its own, need to inform parents about the reasons why this may be occurring in their child and why they need to follow instructions on a day to day basis. Also warn the parents about the chances of relapse and not to loose motivation and give up due to the same. This takes time to improve and be controlled- patience from the child, the parents and the treating doctor goes a long way in treating this condition.