Nocturnal Enuresis

Nocturnal enuresis, the involuntary passage of urine during sleep in children older than 5 years, can be either primary or secondary. Primary enuresis is nighttime wetting in a child who has not been dry for at least 6 months, whereas secondary enuresis is the return of nighttime wetting after a child has been dry for a minimum of 6 months. Enuresis is the most common urologic complaint in pediatric patients and presents frequently in general pediatric or pediatric urologic practices. Often considered a “low-severity high-prevalence' condition, this disorder may be accompanied by extensive psychosocial stress on patients and families. Enuresis causes distress and low self-esteem in children and has additional social and economic implications for the family. For this reason, diagnosis and appropriate management of enuresis is of great clinical importance. Correct and timely treatment can prevent further psychosocial suffering and promote healthy and normal development in children.The prevalence of enuresis varies with age and sex. The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition lists the prevalence as approximately 5% to 10% among 5-year-olds, 3% to 5% among 10-year-olds, and approximately 1% among individuals 15 years or older. Although other references in the literature show a higher prevalence (up to 15%–20% in 4- to 6-year-olds), the observation of decreasing prevalence with age is consistent. The prevalence of enuresis is twice as high in males as in females. Enuresis seems to resolve spontaneously at a rate of approximately 15% per year. However, the longer enuresis persists in a child, the lower the probability of spontaneous resolution.During regular health supervision visits, clinicians should inquire about enuresis because families across cultures may see bed-wetting as a social or domestic issue rather than as a clinical one. Parents who view enuresis as a disciplinary issue may attempt to address it using punitive measures. Punishment has no role in the management of enuresis, does not promote spontaneous resolution, and may further compound the child’s psychological distress.The evaluation of enuresis begins with a thorough history and physical examination. The history should include assessment of sleep disturbances, behavioral issues, and previous management strategies. The voiding history should include inquiry into daytime voiding patterns and complaints. The pattern, frequency, and regularity of stool elimination should be explored, and if the patient is constipated, this should be treated first. The physical examination is normal in most affected patients but is useful to rule out genital or urethral anomalies or abnormal neurologic findings. A full bladder diary documenting a 7-night record of any episodes of incontinence and nighttime urine volume can prove very useful for the clinician. Patients may benefit from questionnaires such as the Pediatric Urinary Incontinence Quality of Life score, which helps measure the psychosocial impact of incontinence on children. In the further evaluation of enuresis, a urinalysis may be useful in assessing for urinary tract infection or occult disease processes such as diabetes mellitus or diabetes insipidus. Radiographic studies play a limited role and should be used only in evaluating copresenting symptoms such as recurrent febrile urinary tract infections, daytime voiding complaints, or cases where there is a high suspicion of anatomic anomalies.Stratifying enuresis as monosymptomatic and nonmonosymptomatic is helpful in planning effective management. A child with enuresis and no other lower urinary tract symptoms such as daytime frequency or incontinence, and who has no proven underlying bladder dysfunction, is considered to have monosymptomatic enuresis. The copresentation of enuresis with any other lower urinary tract symptoms is considered nonmonosymptomatic. The appropriate management for both types of enuresis is summarized in the Table.The use of a bed-wetting alarm is the most effective treatment for monosymptomatic enuresis but requires a highly motivated child and family to commit to its strict daily use. It offers a higher rate of sustained response and a lower relapse rate after discontinuation than does pharmacologic therapy. Such alarms contain a moisture sensor placed in the child’s underwear. This sensor triggers a loud alarm and/or vibration at the onset of urination, with the intent of awakening the patient so the child will get up and finish urinating in the toilet. Parents should be aware that during the first few weeks of use they may be the ones initially awakened by the alarm, not the child. To ensure compliance in such cases, they will need to quickly awaken their child and bring the child to the bathroom to finish urinating.Desmopressin promotes increased antidiuretic activity without associated vasoconstriction and can be used in children with monosymptomatic enuresis. Animal studies indicate that the antidiuretic effect may not be the only mechanism at play: central nervous system stimulation at the locus coeruleus, a nucleus in the pons that is part of the reticular activating system with a role in arousal, is being investigated as another potential mechanism providing benefit. Tablet or nasal spray formulations should be administered approximately 1 hour before bedtime, and more than 1 tablet may be necessary. The adverse effect profile is low. A rapid response to desmopressin is expected, and treatment should be stopped if there is no response after 2 weeks. Situational use of desmopressin (eg, camp and sleepovers) may be effective. The combination of desmopressin and bed-wetting alarms can lead to near-complete response rates, but relapse rates are not insignificant.Nonmonosymptomatic enuresis is often treated pharmacologically with anticholinergic agents. Muscarinic antagonists, such as oxybutynin, are commonly used either alone or in combination with desmopressin. Tricyclic antidepressants, most commonly imipramine, are a secondary treatment for both monosymptomatic and nonmonosymptomatic enuresis: the proposed mechanism of action involves promoting arousal in the central nervous system along with anticholinergic activity. Because of the risk of cardiac adverse events, imipramine should be reserved for older children recalcitrant to other treatments who have no cardiac history and are not taking medications that may predispose them to arrhythmias. Last, atomoxetine, a selective norepinephrine reuptake inhibitor commonly used for management of attention-deficit/hyperactivity disorder, may have a role in refractory cases of enuresis. Urologic referral should be a strong consideration in nonmonosymptomatic enuresis for complete evaluation of any underlying urologic comorbidities, as well as for any patients who are persistent nonresponders to standard therapy.Comments: Aside from the treatment options described in this In Brief, a few other commonsense measures can be helpful in managing bed-wetting in a way that is not threatening to the child. Parents should have their child take fluids generously during the day, before dinner time, to ensure proper hydration, but then avoid drinking after dinner. Eliminating sugary and caffeinated beverages, aside from obvious other benefits, can also be helpful with enuresis. Just before getting into bed at night, the child should go to the bathroom to urinate fully. Some motivated children can benefit by having an alarm set to waken them mid-sleep, either themselves or by a parent, at a time before they wet the bed, going to the bathroom, and then returning to bed.Most important, as Drs Guzman and Palmer stress, is encouraging parents to approach bed-wetting nonpunitively and supportively and to let the child know how common and normal it is for many children to need time before they stay dry at night.Henry M. Adam, MDAssociate Editor, In BriefCorrection: A previous version of this article defined atomoxetine as a serotonin reuptake inhibitor; it is a selective norepinephrine reuptake inhibitor. Pediatrics in Review regrets this error.