Primary Care Pediatrics
1st Edition

CHAPTER 63
Enuresis and Encopresis
William J. Discipio PhD
INTRODUCTION
The current state of scientific knowledge about childhood dysfunctions or delays in bladder and bowel training suggests that good standards of pediatric practice should be proactive. The primary care provider needs to be knowledgeable about advances in early interventions, selecting treatments on an empirical footing. There is no longer a sufficient basis for ignoring the problem, treating with “tincture of time,” or waiting for the child to “grow out of” a presenting problem of self-limiting or monosymptomatic urinary or bowel incontinence.
Most children are physiologically and psychologically ready for successful toilet training before age 4 years, some as early as 18 months. Cultural and familial determinants of the initiation of toilet training vary greatly, with few to no effects on later continence. Persistent failures to achieve diurnal and nocturnal urinary control may signal a need for medical or psychological intervention. The primary care provider should actively investigate the problem, especially if it is raised as a problem by the family. Similarly, the provider needs to intervene if the child experiences the negative psychological impact of not keeping up developmentally with siblings or peers. Chronic and persistent voiding dysfunction associated with high intravesicle pressure and postvoid residual urine can also contribute to infection, bladder decompensation (trabeculated interior), ureteral reflux, hydronephrosis, and ultimately renal failure.
Although the statistical prevalence of serious systemic or psychiatric disorders is low, the difficult-to-train child may be presenting important but subtle diagnostic cues implicating the interaction of the central and autonomic nervous systems. To find a treatment strategy for what is either a psychophysiologic or functional disturbance, the provider must rule out many different causes for the training lag. Cross-disciplinary consultation or referral may be appropriate from specialists in either pediatric urology or behavioral psychology.
Problems of storage and elimination of waste in children pose medical and secondary psychological adjustment and coping problems. The etiology is multidetermined. Therefore, wetting and soiling must be seen as symptoms to be investigated before an efficacious choice of treatment can be made. Incontinence symptoms in children are generally referred to as enuresis (poor bladder control) and encopresis (poor fecal control). These symptoms are rarely indicative of complete loss of function. Obvious lesions or limitations of the central nervous system (CNS) may be present, such as cerebral palsy, severe mental retardation, autism, psychosis, attention deficit disorder, or seizure disorder. In cases in which no primary physical or severe psychiatric diagnosis is present, a functional, or more accurately stated, psychophysiologic, diagnosis is reached by careful elimination of other differential causes for the incontinence. This chapter provides a framework for differentiating organic from functional causes of incontinence, while guiding the provider in appropriate treatment and referral.
ANATOMY, PHYSIOLOGY, AND PATHOLOGY
Normal Bladder Function
Storage and elimination of urine in the infant bladder is entirely an autonomic function, without inhibitory or volitional control connections to the CNS. The bladder itself is composed of smooth muscle, while the length of the urethra contains an increasing presence of striated muscle as it projects distally from the bladder. As the bladder wall accommodates expansion in the storage process, a trigger threshold of fluid capacity is reached. An afferent neural message is sent through the pudendal nerve to sites at S2, S3, and S4, where a synapse is activated with nerves that innervate efferent muscles. Additional neural pathways connect this reflex with regions in the pons and detrusor motor nucleus. The bladder normally contracts in synchrony with the relaxation of sphincter muscle, expelling urine in one continuous stream. When bladder control persists in this automatic fashion in the absence of physical causes, such as a primary disease affecting the nervous system, the child is said to have a pediatric unstable bladder or bladder displaying uninhibited contractions. This can result in a chronic day or night wetting problem.
Primary Diurnal Enuresis
A child who does not show complete daytime urinary continence often experiences repeated and unexpected contractions of the bladder (primary diurnal enuresis [PDE]). These contractions result in intermittent wetting episodes, with accidents occurring at small capacities. Such a youngster has never been dry for a continuous 3-month period. In the presence of an intact nervous system, the child does not respond to a sensation of a gradient of bladder filling but rather will perceive a sensation of the bladder muscle in contraction. In the young child, the most readily available compensatory response to an uninhibited bladder reflex is a volitional contraction of the external sphincter muscles. The child eventually learns to apply pressure on the perineal area by crossing the legs and squeezing the thighs together or performing a “squatting” maneuver by sitting on the heel of one foot. At best, the child is able to inhibit some but not all of the urine flow, because the compensatory maneuver is initiated only after the bladder has begun an uninhibited contraction.
Primary Nocturnal Enuresis
Bedwetting is a relatively common problem that frustrates children and parents long after daytime continence has been achieved. Although the condition most often appears as a monosymptomatic, nonorganically based problem, the psychological impact and persistence of the problem over many years must and should be addressed with active treatment interventions.
Many myths have been constructed about the causes and cures of primary nocturnal enuresis (PNE) that are based on coincidence and faulty logic. These myths have evolved because of the pervasive epidemiology of the problem combined with unpredictable spontaneous remission rates. Speculation has therefore included small functional bladder capacity, dietary influences, allergies, and excessive water intake as examples of mechanisms underlying the incontinence. To date, there is no support that any of these factors is explanatory of a single underlying cause. Although early studies have been confirmatory of small functional bladder capacity, the occurrence of bladder retention in some patients can also occur, especially in the presence of a mild daytime unstable bladder component (Shima et al., 1998; Medel, Ruarte, Castera, & Podesta, 1998). These children may have learned an overcorrective maneuver by chronic tightening of perineal muscles to overcome any symptoms of diurnal urine loss.
Explanatory mechanisms involving bladder storage have explored the notion of small functional bladder capacity interacting with high urine production at night (Rasmussen, Kirk, Borup, Norgaard, & Djurhuus, 1996; Djurhuus & Rittig, 1998). Conclusive evidence on this point has proven to be equivocal. Exceptions to the small functional capacity model are frequent, especially as children get older and often decrease their frequency of voluntary daytime voids because of previously acquired annoyance associated with trips to the bathroom. Norgaard, Djurhuus, Watanabe, Stenberg, and Lettgen (1997) implicated hormonal influences by studying bladder capacity with attention to rate of urine production and urine osmolality. Their findings built on work of a decade earlier, when they documented the presence of an insufficient nocturnal antidiuretic control in some patients with PNE, who were also usually treatment resistant (Norgaard, Pedersen, & Djurhuus, 1985).
Wide-scale distribution of DDAVP, a synthetic form of vasopressin, has shown the drug’s dramatic immediate effects on abating PNE. Recurrence of symptoms after the drug is withdrawn is high, however, suggesting that a pharmacogenic solution is not likely to “jump-start” the youngster who may have a vasopressin deficiency.
Depth of sleep is another competing controversy in the pursuit of an etiologic model for PNE. Many parents and primary care providers have assumed that the bedwetter sleeps too deeply and therefore cannot respond to full bladder cues to awaken and toilet at night. A contradictory view is apparent when one considers that very few normal children awaken at night to void, and if they do, such awakening might be considered a pathologic symptom of nocturia. In addition, children sleep more deeply than adults. This fact might result in a false conclusion that the child is an abnormally deep sleeper when a parent tries to awaken the child to void and keep the bed dry. For many years, studies monitoring electroencephalograms (EEG) and enuresis showed no relationship between depth of sleep and enuretic events in the absence of a known paroxysmal or primary seizure disturbance (Wolfish, Pivik, & Busby, 1997).
Conversely, increasing numbers of recent scientific reports suggest that a possible deficit in CNS arousal underlies PNE (Kawauchi et al., 1998a; Watanabe, Imada, Kawauchi, Koyama, & Shirakawa, 1997). Clinical observations confirming that arousal factors may be implicated include the tendency for the child with PNE to sleep dry on occasion when going to bed very late or sleeping in a different bed when away from home (eg, at sleepovers or at relatives’ houses). Jenkins et al. (1996) and Neveus, Lackgren, Tuvemo, and Stenberg (1998) found that children with PNE were indeed harder to bring to full awakening than a nonenuretic population. PNE has also been classified along the lines of arousability by sleep researchers who propose three distinct clinical groups (Watanabe, 1998; Imada et al., 1998):
  • Type I: Detectable change in EEG activity in response to bladder distension and stable cystometrograms
  • Type IIa: No detectable change in EEG; stable cystometrograms
  • Type IIb: No detectable change in EEG; unstable cystometrograms only during sleep
Kawauchi et al. (1998b) propose that type I may involve an immaturity in the function of the thalamus, while type IIa may implicate the pons or the lower urinary tract. Type IIb most closely resembles a neurogenic bladder profile. Refer to Chapter 62 for more information about the use of medications in managing PNE.
Functional Encopresis
Chronic encopresis is mostly an outcome of functional or behavioral causes for stool retention or inappropriate bowel elimination habits. Physical causes or syndromes are consequently an unlikely reason for a child’s encopresis. An exception is Hirshsprung’s disease, which is an anatomic basis of stool incontinence. Hirshsprung’s disease is often apparent at birth or is identified long before the child is seen for encopresis. Other problems involving the integrity of the rectal sphincter and spinal cord innervation also must be considered before accepting a functional cause for incontinent stool loss. Children with functional encopresis (FEN) do not have identifiable anatomic malformations or neurogenic lesions. Abnormal pudendal nerve function, which often
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contributes to fecal incontinence in adults, does not appear to be implicated in FEN (Sentovich et al., 1998).
The most common presentation of encopresis is a minor stool loss or staining of the underpants (“skid marks”) accompanied by retentive toileting habits. Stool retention results in the compaction of large amounts of hard feces in the lower bowel. The passage of loose stool from farther up the intestine is then allowed to “leak” between the hardened stool and the wall of the lower bowel. Many parents mistake the cause of soiled underpants as being related to poor hygiene or wiping technique.
EPIDEMIOLOGY
Primary Diurnal Enuresis
About 1% to 5% of children are believed to experience daytime wetting in the absence of physical findings, including bacterial infection of the lower urinary tracts (Bower, Moore, Shepherd, & Adams, 1996). However, Swithinbank, Brookes, Shepherd, and Abrams (1998) reported that a recent survey of 1176 healthy English school children revealed prevalence estimates as high as 12% for day wetting in children aged 11 to 12 years. Nevertheless, the prevalence is much greater in girls than boys. This sex difference is probably related to higher incidence of chronic urinary tract infections (UTIs) seen in girls with PDE, secondary to the shorter urethral distance in girls, which may carry bacteria to the bladder.
Primary Nocturnal Enuresis
Primary nocturnal enuresis occurs in about 10% of all 5-year-old children who are otherwise normal in all other developmental functions. This estimate would include from 5 to 10 million children in North America. The National Kidney Foundation estimates that 5 to 7 million children age 6 years or older have PNE (1999). The prevalence rates vary among cultures, although the condition is documented among all cultures and racial groups (Kalo & Bella, 1996; Trombetta, Savoca, Siracusano, & Liguori, 1997; Chiozza et al., 1998; Chao et al., 1997; Yeung, 1997; Serel et al., 1997; Popper & Steingard, 1996; Byrd, Weitzman, Lanphear, & Auinger, 1996).
It is estimated that up to 70% of children with PNE have a primary relative who shares that history. There is also a 67% concordance rate for identical twins. Recent discoveries of genetic markers for PNE have clearly established a genetic basis of PNE (Hublin, Kaprio, Partinen, & Koskenvuo, 1998; von Gontard, Eiberg, Hollmann, Rittig, & Lehmkuhl, 1997; von Gontard et al., 1997; Arnell et al., 1997; Eiberg, 1998; von Gontard, Eiberg, Hollmann, Rittig, & Lehmkuhl, 1998).
The most conventional criterion for diagnosing PNE is wetting the bed on average at least two times per month. The number of children remitting without treatment is about 15% per year, which reduces the prevalence to 1% by puberty (Petrican & Sawan, 1998). When considering whether PNE will persist into adulthood, Hjalmas (1997) asserts that, if not treated, 10% of these youngsters will persist with PNE for life.
Special needs children have higher rates of PNE. This is especially true for youngsters diagnosed with attention deficit disorder with hyperactivity (ADHD). PNE in such children may in part be related to a “hyperactive” bladder or to behavioral problems encountered in toilet training. These problems may have emerged because of attentional impediments to efficient learning. Pervasive and chronic hyperactivity of the parasympathetic nervous system may also pay a role in uninhibited bladder contractions (Yakinci, Mungen, Durmaz, Balbay, & Karabiber, 1997). Refer to Chapter 21 for more information on diagnosing and managing ADHD.
Functional Encopresis
Prevalence rates of FEN are frequently underestimates of actual occurrence. This may be a result of mild forms of stool loss going unnoticed or being tolerated by family members. Reasons for this tolerance may be multidetermined and can involve individual family and culture-bound attitudes toward hygiene or the belief that stool loss is not a treatable, medical symptom.
HISTORY AND PHYSICAL EXAMINATION
A well-informed parent or guardian is invaluable in establishing a confirmatory history of PDE, PNE, or FEN. A family history of wetting problems in parents or any primary relative is very helpful in identifying the genetic basis of many forms of functional bowel and bladder disturbances. A thorough but noninvasive routine evaluation for enuresis and encopresis starts with a structured interview, as demonstrated in Display 63-1, Display 63-2, and Display 63-3.
A thorough physical examination should be performed, with urine obtained for analysis and culture. The provider should also order a bladder ultrasound if poor bladder emptying or an unusual urinary stream (eg, intermittent flow) is known or suspected (Lettgen, 1997; Kawauchi, Kitamori, Imada, Tanaka, & Watanabe, 1996; Pippi Salle et al., 1998).
The clinician may find that child and parents have a limited accuracy for recalling soiling episodes. This is common, underscoring the need for the collection of prospective data (van der Plas, Benninga, Redekop, Taminiau, & Buller, 1997). Parents are often not aware of damp or soiled underwear during school hours and do not take note of their presumably trained youngster’s daily bowel movement activities.
DIAGNOSTIC CRITERIA
Primary Diurnal Enuresis
Children with PDE wet themselves during the day, in the absence of anatomic, neurologic, infectious, or pharmacologic iatrogenic causes. The differential diagnosis must also rule out causes secondary to family stressors, child abuse, or psychiatric crises (secondary diurnal enuresis). The problem of daytime wetting is usually characterized by small losses of urine throughout the day, although the cumulative loss may be greatest in the late afternoon and evening when the
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bladder may be fatigued or liquid intake is at a maximum. The actual incontinent episode is associated with a reflexive partial bladder contraction and is not a result of incompetent sphincter function. “Squatting” maneuvers or obvious physical signs that the child is trying to inhibit a full bladder contraction are evident in 3- to 5-year-olds. Older children show more skill at unobservable urethral striated muscle contraction, keeping their perineal muscles at a chronically high resting potential.
Primary Nocturnal Enuresis
“My child wets the bed” is usually not reported as early as the daytime wetting of the child with PDE, because the latter condition is more socially distressing and may be accompanied by a symptomatic UTI. Many parents wait until at least school age (5 years) or later, when social demands, such as sleep-overs or sleep-away camp, necessitate attention to curing the bedwetting problem. Additional intrafamilial pressures, such as the competition imposed by dry siblings who may be younger than the bedwetter, also drive the need to seek treatment.
The following inclusive evidence confirms the diagnosis of PNE:
  • Positive family history for PNE, and
  • Persistent bedwetting at least two times per month for several months or 1 year and never dry for 3 months of consecutive nights
Exclusionary criteria for diagnosis include the following:
Functional Encopresis
Functional encopresis is a disturbance of bowel elimination involving the involuntary loss of formed or liquid stool after the age of culturally acceptable limits of toileting training. A pattern of sluggish bowel movement behavior is almost always associated with FEN. The American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders, fourth edition (1994), describes this subtype as encopresis with constipation and overflow incontinence. A secondary subtype, described as encopresis without constipation and overflow incontinence, involves more volitional behavior that may accompany an additional psychiatric diagnosis of oppositional defiant disorder in young children and conduct disorder in older children. The possibility of a psychotic disorder may also be implicated, as might anxiety syndromes or symptoms associated with severe sexual abuse or sodomy.
The following inclusive evidence confirms the diagnosis of FEN:
  • Stool soiling occurring at least once a month and persisting for several months in the absence of diarrhea secondary to a medical condition or inappropriate use of laxatives, stool softeners, or lubricants, such as mineral oil
Exclusionary criteria in the diagnosis of FEN include the following:
  • Encopresis secondary to a medical cause, such as Hirschsprung’s disease, anal or rectal malformation or trauma, spinal cord anomalies (mylomeningocele) or spinal cord injury, cerebral palsy, mental retardation, or physical abuse
  • Encopresis secondary to side effects of medication, such as antibiotics (Loening-Baucke, 1996)
Functional encopresis may also be considered as a diagnosis from either a primary or secondary perspective. Foreman and Thambirajah’s (1996) examination of boys who failed to establish toilet training (primary FEN) provided evidence that these children had a greater likelihood to have developmental delays and PNE. Conversely, boys who displayed a breakdown in previously established toilet training (secondary FEN) were more likely to present with symptoms consistent with an excess of psychosocial stressors. They were also more likely to have the comorbid diagnosis of conduct disorder. The reader should refer to Chapter 21, Chapter 23, Chapter 26, Chapter 27, and Chapter 28 for a more in-depth examination of these issues.
DIAGNOSTIC STUDIES
Bladder instability has long been thought to play a central role in the etiology of chronic diurnal enuresis (Chandra, 1998). A mechanistic approach to understanding diurnal enuresis as bladder instability carries considerable intuitive validity because the child seems to be caught off-guard when unexpected bladder contractions occur. These contractions lead to otherwise unexplained symptoms of urgency, frequency, and compensatory squatting maneuvers.
The first empirical evidence for this hypothesis was documented by McGuire and Savastano (1984) and Firlit, Smey, and King (1977) in urodynamic studies that showed uninhibited contractions when filling the bladder using urethral catheters or suprapubic vesicle tubes. The limitations of these urodynamic studies include iatrogenic effects of the intrusive nature of the tests, which may have produced artifactual pathogenic findings. There is also the likelihood that patients selected for comprehensive urodynamic study are the more serious cases who have not responded to conservative treatment, so they may represent an occult neurogenic group. In addition, bladder suppression by pharmacogenic agents, such as oxybutynin often results in improvement of wetting symptoms. The effect is usually only temporary, affording symptom relief but not a final solution to the problem. Because the diurnally enuretic child displays behaviors similar to children with identifiable
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neurogenic lesions, this syndrome has been labeled the non-neurogenic neurogenic bladder and the pseudoneurogenic bladder (Hanna et al., 1981) or is referred to in the urologic literature as the Hinman syndrome (Hinman, 1986).
A contrasting and more recent hypothesis to explain diurnal wetting and comorbid chronic UTIs is the focus on the overtightening of the perineal floor as the primary mechanism. Children demonstrating bladder-sphincter dyssynergia while voiding are using the striated sphincter in an inefficient and maladaptive fashion, preventing the free flow of urine through an obstructed urethra. Collateral afferent pathways connect the external urinary sphincter with the bladder, which may result in further disruption of bladder functioning by inhibiting the full contractile reflex of the bladder. A partial bladder contraction will cause postvoid residual urine, a condition often seen in children with the Hinman syndrome. The sequela of postvoid residual urine often optimizes the conditions for bacterial growth, adding to the risk of bacterial infection introduced in chronically wet underpants. Biofeedback treatment raises cognitive awareness of the bladder-sphincter dyssynergia problem. Biofeedback has provided confirmatory evidence that the pelvic floor is a salient factor in cause and cure of the problem (Herndon, McKenna, Connery, & Ferrer, 1998).
Further helpful, relatively nonintrusive diagnostic measures for studying PDE or bladder-sphincter dyssynergia include measurement of the hydrodynamics of the urinary stream (flow study) and electromyographic recordings of the perennial floor during voiding with external skin electrodes. These measures are relative easy to perform when good rapport is established with the child. The parent may be present during these tests, which require the child to be alert and fully cooperative. The tests should follow any urine analyses or culture but may prove helpful even before deciding to perform an intravenous pyelogram (IVP), voiding cystourogram (VCU), or cystometrogram.
Although a child’s developing self-esteem and social functioning may be at risk as the child grows older, PNE usually does not have comorbid primary psychiatric components (Friman & Jones, 1998). Psychiatric concerns most often arise with secondary forms of enuresis. A child who has experienced a period of complete and successful toilet training of at least 3 months and resumes wetting may be exhibiting a psychological sequella of faulty stress-coping mechanisms. These faulty mechanisms may follow post-traumatic stress disorder or sexual or physical abuse (Faust, Kenny, & Runyon, 1997). Referral to a mental health professional is warranted. Such referral is especially important if the urologic symptoms are comorbid with signs of behavioral distress, depressive ideation, or poor parenting conditions (Geroski & Rodgers, 1998).
MANAGEMENT
Efficacious treatment options of incontinence are varied. They may be classified as follows:
  • Psychological—any methodology aimed at retraining bladder or bowel functioning, assisting the family with behavioral management, or counseling patient and family regarding prognostic and preventive measures and collaborative treatment with the assistance of a behavioral psychologist or urologic nurse specialist
  • Medical—all prescriptive pharmacogenic approaches and special instructions concerning advisability of altering intake of fluids; restricting caffeine and carbonated sodas; use of laxatives, stool softeners, and lubricants, such as mineral oil
Conversely, symptoms or treatment response may point toward the need for referral, enlisting the assistance of a medical specialty when birth defects, neuropathology, or comorbid medical or psychiatric conditions are known or suspected.
The child whose only symptom is nocturnal enuresis should be evaluated by both interview and prospective symptom observation. Parents should be asked to chart signs of diurnal urinary problems. These problems include diurnal frequency, retention, and wetting. Busy families often overlook minor occurrences of these symptoms. Children find ingenious ways of hiding or denying these annoying, socially intrusive manifestations. If any symptoms are present, the seven-void program is recommended. Stabilization of daytime voiding habits can contribute to better treatment response in a nocturnal program. Treatment gains and successful participation can lead to positive rewards, not the least of which is continence.
Corrective behavior modification interventions, such as establishing a controlled voiding program, should be suggested by the primary care provider if the initial clinical interview reveals the presence of minor encopretic events (soiling) or retentive bowel habits (skipping one or more days without a bowel movement). Return clinic visits should be scheduled over the full course of active behavioral contingency management. Visits may be spaced at increasingly longer intervals as progress is achieved in alleviating symptoms.
The child with diurnal enuresis is most likely to be seen first by the primary care provider. Referrals are often made because family distress is driven by social embarrassment and stigma, rather than because of presentation of “medical” symptoms or distress. The clinician should remember that many children with diurnal enuresis have UTIs. The clinician must also consider whether to treat for an acute event or, if the UTI is not the first one, whether to continue medication prophylactically. Long-term use of antibiotics must be weighed against the possibility of breakthrough infections. Such infections render one medication ineffective and potentially exhaust options for using other agents. Figure 63-1
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presents a diagnosis-to-treatment algorithm that the primary care provider may find helpful in managing or choosing to refer enuresis and encopresis in children.
Figure 63-1 Diagnostic, treatment, and referral flow chart.
Approaches to Bladder Retraining
Psychological approaches to retraining toileting behavior are not recommended during the course of an active infection. However, some form of training or efforts at normalizing voiding and defecating schedules should begin immediately after bacterial growth is arrested and symptoms have abated. A voiding schedule for children ages 5 to 12 years would require about seven voids per day. This frequency is slightly more than the normal rate of two to five voids per day. The increased programmed voiding program is aimed at optimizing bladder emptying by avoiding overdistention and reaching trigger capacity. This is because excessive urine storage may contribute to uninhibited contractions and wetting.
Biofeedback therapy is an appropriate option if there is clear documentation of either a bladder-sphincter dyssynergia or an inability to empty the bladder to completion. The method requires specialized equipment and trained biofeedback therapists who have experience working with children. Elimination of bladder-sphincter dyssynergia is accomplished, in part, by raising awarenenss of volitional control of the sphincter muscle while reducing overactivity of abdominal muscles. External electrodes are pasted on the perianal skin and abdominal areas, and the child is taught a computer assisted Kegel exercise. Emptying to completion may also be trained by combining electromyographic feedback with pre-and post-voiding bladder sonography and uroflowmetry (Pfister, et al., 1999; Porena, Costantini, Rociola, & Mearini, 2000).
Controlled (Timed) Voiding Regimen
Before prescribing the controlled voiding regimen, the child and family should be fully educated and counseled regarding its rationale. Parents should prompt, not force or coerce, their child into going to the toilet at the programmed times when there may be no internal sensation of fullness or perception of an uninhibited bladder contraction. It is a good idea to construct the schedule with a parent handout showing daily routine home and school activities to which a toileting reminder can be associated. Figure 63-2 presents a sample weekly chart for a seven void per day program.
Figure 63-2 Weekly chart for seven-void program.
Integrating toileting reminders into a child’s schedule avoids the problem of “timed voiding.” Requiring voids by watching the clock may exceed the young child’s ability to
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tell time. Timed voiding is also problematic because it adds time-focused pressure and stress—difficult for anyone, regardless of age. At least three voids are required during school hours. Parents may need to enlist the confidential cooperation of a home-room teacher or school nurse to provide reminders. A system of positive reinforcement for each toileting attempt can be planned with the use of sticker charts for children between 4 and 8 years of age. Older children will require some form of an allowance system (usually monetary). Parents can be told that the rewards are contingent on positive behavior at maintaining the voiding program, not on having dry pants. Dryness itself is only an outcome of successful voiding behavior.
Other Methods for Achieving Continence
Urine Alarms
The use of a urine sensor and alarm apparatus for treating PNE has been around for a considerable time (Mowrer & Mowrer, 1938). Use of this method has proven effective in as many as 90% of families who choose to participate in a full course of treatment. The method is labor intensive, disruptive of parent and child sleep patterns, and takes considerable time and patience. Many parents initiate this program on their own but fail because of premature termination of training. The labor- and time-intensive factors may also contribute to the tendency for many providers to delay treatment while awaiting spontaneous remission or to prescribe medication as a primary intervention. The original apparatus (bell and pad) consists of two electrically conductive pads placed between and covered by bed sheets. When the child wets the bed, the auditory alarm connected to the now-completed circuit (urine between the pads) wakes the child and alerts the parent. The youngster is then led from bed to the toilet, where the void is completed.
For these reasons, the provider should screen for and discourage use of older bell-and-pad apparatuses.
State-of-the-art forms of the apparatus now are battery-driven. The alarm unit attaches to the pajama or straps to the wrist. A wire extends from the alarm unit to metal clips which pin to the inside and outside of the underpants. With only a few milliliters of urine in the underpants, the alarm is triggered, sounding like a phone pager. This device poses no electrical danger to the child. The alarm must be unpinned to stop activation of the noise.
Parents must be prepared to use the microalarm system for 2 to 3 months before signs of improvement can be measured or complete dryness attained. Prepubescent children will almost certainly require assistance of one parent during the night; therefore, the parents must be prepared for disturbances in their own sleep patterns. The scientific explanation for the alarm system’s effectiveness has not been firmly established. The provider can tell parents only that the alarm provides an arousal cue, which prevents the child from finishing the void in bed. A reasonable but overly simplified explanation is based on an avoidance paradigm of autonomic learning, in which the CNS is provoked into sending inhibitory messages to the bladder to avoid repeated sleep disturbances.
Improvement in self-esteem is often an accompanying outcome when a child and family are successful in achieving continence with the alarm (Schulpen, 1997; Longstaffe, Moffatt, & Whalen, 2000). This active treatment plan involves the child and family in comanagement of PNE. The plan most likely contributes to a good experience and acts as a positive contrast to spontaneous cures or pharmacologic interventions that only require taking a prescribed medication. An enuretic alarm costs the same as a 2-week supply of DDAVP (Schmitt, 1997).
Dry Bed Training
Dry bed training (Azrin, Sneed, & Fox, 1974) combines alarm training, reinforcement techniques, and urine retention control. Unfortunately, the method has proven to be only slightly better than an alarm-alone system (Hirasing, Bolk-Bennink, & Reus, 1996). A precaution is necessary in using a component described as behavioral urine retention training. Because daytime frequency has not been a consistent finding in all children with PNE, the practice of daytime urinary retention (“bladder stretching”) may at best add unnecessary stress or at worst may exacerbate an already present problem of high-pressure bladder conditions, bladder trabeculation, or ureteral reflux. Reflux is difficult to diagnosis without imaging techniques. Reflux raises the risk of hydronephrosis or kidney infection if bacterial growth is present in the bladder.
Medication
Medication is used as a first-line treatment by as many as 52% of physicians (Vogel, Young, & Primack, 1996). This practice belies the evidence that sustained outcome after stopping medication is dismal and that side effects are troublesome. Ever since Maclean (1960) found that imipramine, a drug developed to treat depressive illness, had antidiuretic properties in the elderly, its use has been widely applied to treat children with PNE. Imipramine is an anticholinergic agent and a noradrenergic stimulant. It was thought to effect bladder contractility by increasing the threshold capacity. More recently, imipramine has been linked to changing arousal thresholds. Efficacy rates of 60% response while on the drug and 70% recurrence when off the drug are disappointing for a definitive first-line treatment.
Oxybutynin provides an anticholinergic action on the detrusor muscle, which may temporarily result in a reduction of bladder spasms and a secondary gain in bladder capacity in the child with diurnal enuresis with urinary frequency problems. Oxybutynin has not proven efficacious in any form of PNE.
More recently, work in Scandinavia has focused on the hormonal pathways controlling the kidney production of urine. Norgaard and colleagues (1985) were among the first researchers to propose that treatment-resistant children showed a hormonal deficiency. Their research focused on a deficiency in the production of plasma arginine vasopressin. This antidiuretic hormone is secreted by normal children and results in reducing urine output to the bladder as the sleep cycle progresses into the night. Introduction of an artificial form of the antidiuretic hormone (DDAVP) showed great promise in abating symptoms during active drug treatment. However, the problem with DDAVP is recurrence of symptoms when the drug is discontinued. Medication can provide an immediate form of relief of bedwetting, but it is not a permanent solution for PNE. Some parents may want to consider medication for temporary solutions like vacations, sleep-overs, or summer camp. As with all medications, the risk of side effects must be considered carefully by parents.
Incontinence Comorbidity
The problem of FEN may coexist with enuresis (O’Regan, Yzback, Hamberger, & Schick, 1986) or may occur alone. In either case, primary treatment should involve methods of behavior modification. Behavior modification can help in establishing a differential diagnosis of a nonorganic functional disorder if the child responds well to the intervention. Behavior modification can also provide an active, effective treatment for maladaptive bowel habits in the same way that applications to bladder training are efficacious.
When a diagnosis of encopresis with overflow fecal incontinence is established with children approaching school age (chronologic age of at least 4 years), the problem of relieving fecal impaction is the first order of business. Some gastrointestinal specialists advise mild laxatives, such as senna (Senokot), or pediatric enemas, such as children’s Fleet, to remove the large collection of fecal material in the lower bowel.
A slower but equally effective approach to treating mild impaction may be taken by immediately initiating dietary changes assisted by a behavior modification program of bowel movement attempts. This program requires at least two bowel movement attempts daily, which are monitored and reinforced by parents (Reimeres, 1996). Stark et al. (1997) found that 59 children with retentive encopresis showed soiling decreases of 85% with a combined dietary and behavioral management program. The dietary program aims to increase the quantity of fiber in the child’s diet by adding foods including fruits, fresh vegetables, and salads. A small daily quantity (1 teaspoon) of unprocessed wheat or oat bran is also very effective with younger children. It can be made palatable by mixing with applesauce or a favorite cereal. It can also be used as a cooking additive with muffins, breads, and soups.
The provider should reinforce the importance of avoiding repeated use of laxatives. Laxatives pose a risk of dependency and preclude self-controlled learning of normal full bowel sensations and volitional defecating. If lubricants such as mineral oil are used on a routine basis, they are more likely to exacerbate the problem because of increased leakage around entrapped stool formations.
Rectal biofeedback therapy has been reported as unsuccessful in controlled studies in treating anismus as defined by dyssynergic external anal sphincter contraction during attempted defecation (Nolan, Catto-Smith, Coffey, & Wells, 1998; Loening-Baucke, 1996; van der Plas, Benninga, Redekop, Taminiau, & Buller, 1996). Poor results with this method may be attributed to neglect of dietary adjustment and generalization of rectal sphincter training to the home setting. On the other hand, successful biofeedback interventions have been reported in one case of a postsurgically corrected imperforate anus (Griffiths & Livingstone, 1998).
What to Tell Parents
Setting up a behavioral program is most effective when all adult members who share parenting functions attend at least one meeting, usually the first treatment planning visit. Parents who understand and accept the treatment rationale and who are willing to provide closely monitored toileting prompts, instructions, and rewards for appropriate behavior will have the most efficacious and immediate results. The primary care provider may need to refer inaccessible or discordant families to a mental health or family therapy specialist.
COMMUNITY RESOURCES
National Kidney Foundation (NKF)
30 East 33rd Street, Suite 1100
New York, NY 10016
Telephone: For PNE: (888) WAKEDRY
For other problems: (800) 622-9010 or (212) 889-2210
Fax: (212) 889-9261
Internet address: http://www.kidney.org
A brochure is available, as well as referral to providers who have indicated a willingness to treat bedwetting. This foundation provides information for parents and professionals regarding kidney and urinary tract diseases and referral services to pediatric nephrologists who specialize in kidney and bladder dysfunction.
American Urological Association
1120 North Charles Street
Baltimore, MD 21201
Telephone: (410) 727-1100
Fax: (410) 223-4370
Internet address: http://www.auanet.org
This is an important resource for parents and primary care providers in locating a qualified pediatric urologist.
American Psychiatric Association
1400 K Street, N.W.
Washington, DC 20005
Telephone: (202) 682-6000
Fax: (202) 682-6850
Internet address: http://www.psych.org
This group is helpful for parents or referring primary care providers in locating qualified child or adolescent psychiatrists if coexisting mental health problems, including ADHD, post-traumatic
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stress disorder, child abuse, or neglect, are known or suspected. Psychotropic medication prescribed by a child psychiatrist may be very helpful in assisting behavioral enuresis and encopresis treatment programs.
American Psychological Association
750 First Street, N.E.
Washington, DC 20002
Telephone: (202) 336-5500
Internet address: http://www.apa.org
This association helps parents and referring primary care providers to locate qualified child or adolescent behavioral or family psychologists to provide behavioral bladder or bowel retraining or to provide treatment of coexisting mental health problems (such as problems with compliance, self-esteem, and intellectual and emotional disturbances), which often accompany secondary enuresis and encopresis.
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