ISSUES IN PEDIATRIC UROLOGY
From the Southern California Permanente Medical Group 2006 Urology Symposium
| DYSFUNCTIONAL ELIMINATION, UTI, AND VUR: NEW CONCEPTS AND APPROACHES —Steven J. Skoog,
MD, Professor of Surgery and Pediatrics, Oregon Health and Science University, and Director of Pediatric Urology, Doernbecher
Children’s Hospital, Portland, OR
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| Epidemiology: overall incidence of urinary tract infections (UTIs) 3% in girls, 1% in boys
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| Diagnosis of UTIs: difficult to do clinically, especially in pediatric patients; bag specimens have been relied on universally
(but sensitivity and specificity low); caveat—if bag specimen tests positive, must obtain catheterized urine specimen to
confirm results; gold standard is quantitative urinary culture
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| Bacteria: important (end result of the inflammatory process); P fimbriae—adhesive factors that provide increased virulence
to bacteria; also account for increased incidence of UTIs in uncircumcised neonates
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| Comments: definition of “elimination” is to expel from the living body; majority of patients in pediatric urology present
with voiding problems, UTI, or vesicoureteral reflux (VUR); need to consider all 3 together when examining patient with
any of these problems, as they do interact
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| Eliminology: normal—on average, patients 3-12 yr of age void 5-6 times/day, have 6.8 +/- 2.5 bowel movements/wk;
18% have diurnal enuresis, 10% have nocturnal enuresis; observations—parents not aware of children’s elimination
habits; children not reliable historians; older children deny knowledge of elimination habits; documentation/categorization
of problem—elimination diary key; successful toilet training—requires increased bladder capacity, voluntary
control over external urethral sphincter, and ability to initiate/inhibit detrusor contraction voluntarily; abnormality in control
of external sphincter (dysfunctional elimination) leads to functional urinary obstruction and, in turn, to development
of UTI, enuresis, or VUR
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| Dysfunctional elimination: syndromes include urge incontinence, diurnal enuresis, frequent voiding, constipation, detrusor
instability, and Vincent’s Curtsey maneuver
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| Dysfunctional evacuation: constipation defined as straining >25% of the time, hard stools, <3 bowel movements/wk, palpable
mass, and painful bowel movements; functional bowel obstruction or dysfunctional evacuation due to holding results in
clinical symptoms of constipation and encoporesis; amount of stool can deform base of bladder, resulting in bladder instability
and enuresis (this can increase postvoid residual and lead to UTIs and hydronephrosis); treatment—many patients
with voiding dysfunction (especially those with associated VUR) require both polyethylene glycol (Miralax) and nitrofurantoin
macrocrystals (Macrodantin); managing constipation can be extremely effective in decreasing urinary symptoms
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| Association of dysfunctional elimination/VUR/UTI: retrospective review of patients with primary VUR found 33% also
had problems with dysfunctional elimination; this group was in turn responsible for 82% of breakthrough UTIs and majority
of reimplantations and surgical failures; therefore, if treatment of patient with VUR does not include management of
dysfunctional elimination, consequences of VUR will be worse
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| Imaging children with UTIs: pediatric urologist’s concern is to make sure patients do not have associated problems with
obstruction or VUR; traditional method of evaluating children for VUR after first UTI is renal bladder ultrasonography
and voiding cystourethrography (VCUG); results determine further radiologic studies and treatment; in reality, persistent
obstructive problems only seen in 1% of children who present with acute UTI (VUR still a concern, as it remains the most
important risk factor for renal damage and renal scarring; present in 35% children with UTI at time of initial evaluation)
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| Dimercaptosuccinic acid (DMSA) renal scan: excellent method of evaluating damage to kidneys due to UTI; unfortunately,
scan cannot predict or rule out development of renal scarring in patients who present with acute pyelonephritis
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| Reconsideration of imaging protocol: study by Hoberman et al reviewed results of imaging in 302 febrile children who
presented with a first UTI; 61% of patients had normal VCUG (of those who had VUR, >80% had low-grade [I-III] reflux,
which is associated with much lower risk for scarring than dilating [grades IV-V] VUR); in addition, 88% of renal
ultrasonography tests were normal; only 3% of cases would have required urologic intervention; results such as these
have lead to questioning value of present imaging protocol for children with UTIs, and suggestion of different approach
(first doing DMSA renal scan to identify patients who would require VCUG)
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| Treatment of VUR: options include antibiotic therapy, open surgery, and endoscopic injections; treatment principles (VUR
often resolves spontaneously; sterile reflux does not damage kidney; prophylactic antibiotics effective in treating UTIs);
resolution related to grade of VUR, age at presentation, bilaterality, and sex; resolution rate for grade III VUR 15% to
20% per year; no studies have been able to predict which patients with, eg, grade III VUR, resolve spontaneously; currently,
no consensus on how to manage low-grade VUR after period of prophylactic antibiotics
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| Endoscopic therapy: available since 2001; patient receives injections of dextranomer/hyaluronic acid (Deflux); easily delivered
(can be done by cystoscope); minimally invasive (outpatient procedure); substance can be injected underneath ureter,
raising up mound, creating new flat-valve mechanism to treat VUR; summary of experience at speaker’s institution over last
5 yr; worth considering prior to open surgery or prolonged antibiotic therapy in patients who require correction of reflux
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| CONSTIPATION AS IT RELATES TO VOIDING DYSFUNCTION —Frederick D. Watanabe, MD, Associate Clinical
Professor, David Geffen School of Medicine at the University of California, Los Angeles, and Pediatric Gastroenterologist,
Southern California Permanente Medical Group, Los Angeles
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| Introductory remarks: important to distinguish what is functional from what is physical; while majority of pediatric gastroenterologists
and probably all pediatricians still frame constipation as “functional” problem, where child’s behavior
needs to be modified, there is increasing evidence of physical problems (eg, inability to appreciate stool bolus; inability
to defecate or to push out stool bolus) that form nidus for creating behavioral issues; since no medications exist to manage
these mitigating factors, therapy still favors behavioral changes; successful constipation management requires parental
“buy-in” and cooperation as well as child’s compliance
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| Incidence of constipation in children: defecation difficulties most common problem seen by pediatric gatroenterologists;
>51% of speaker’s practice at current institution for constipation specifically; another 31% of patients seen for abdominal
pain and end up having constipation; national average much lower (about 30%-40%); age of patients varies, but majority
2-10 yr
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| Comorbidity with urinary problems: approximately 30% to 35% incidence of constipation or constipation-related complications
in children with urinary tract problems (either urinary retention or UTIs); constipation not only associated with
disease process and clinical presentation, but also modifies tests required for patient evaluation
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| Definition of constipation: many academic definitions of constipation; speaker suggests “more pragmatic definition” of
constipation as stool uncomfortable to pass; constipation not necessarily time-dependent and not necessarily volume-dependent;
however, child who has firm, uncomfortable stools definitely has constipation; when patient reports discomfort,
important to determine whether secondary to retained stools or pain resulting from discoordination of defecation mechanism
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| Other definitions: fecal retention; overflow stools; encoporesis
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| Normal stool passage: in adults, 3 bowel movements/day to 3/wk considered relatively normal; range in children and infants
can be quite broad (eg, in breast-fed infants, defecating after every feeding considered normal; formula-fed babies
tend to defecate less frequently (3-5 times/day); as children transition to solid foods, stools become less frequent and
more mature in terms of frequency (normal range same as in adults); teenagers should follow adult norms; again, frequency
does not equal retention
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| Talking to parents about fecal retention: speaker frames it as behavioral vs biologic issue; tries quickly to assess parents’
frame of mind (some quite receptive to idea that retention is behavioral/neurodevelopmental problem; others are not); in
talking to them, speaker explains retention as biologic problem; by giving them graphic description, most parents able to
understand problem and buy in to concept that they need to keep child’s colon as empty as possible
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| Constipation in infants: differential diagnosis needs to include high suspicion for anatomic malformations, eg, anteriorally
displaced anus (essentially variation of imperforate anus)
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| Retention management: clinicians can be more aggressive in giving polyethylene glycol; management for these patients
simple, and will work if parents follow instructions (again, lead-up discussion before management important); management
includes scheduled toilet time; many different laxatives can be used (eg, mineral oil; milk of magnesia); dietary
changes not that important; teach patient and family to be persistent in dealing with problem; speaker has adopted use of
“bowel clean-outs” to get stool moving (reduces size of colon and improves function); unfortunately, recidivism rate high
(about 60%-70% in most series)
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| Key for children going to bathroom: assume correct position; comfortable setting; hips flexed, and knees elevated; going
to bathroom should not be punishment (patient needs to understand the purpose is to defecate; stay for minimum amount
of time, eg, not >10 min; otherwise, bathroom becomes a prison); speaker likes to use incentive systems
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| Polyethylene glycol: safe when used in small doses (when used in high doses, tends to leach electrolytes from colon);
nearly tasteless; can be mixed with any fluid; inert substance; does not cause gas; speaker starts with 1 g/kg per day and
goes up to 1.5 g/kg per day (although does not recommend this, will go even higher if necessary, on temporary basis, to
get child to go on regular basis)
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| Tegaserod maleate (Zelnorm): speaker does not use because there is essentially no safety data in pediatric patients, and no
published pediatric dosing data
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| Mechanical management: first thing speaker does when patient presents is perform examination to determine whether patient
can squeeze anus; if there is no control of anus, patient will not have continence; only option then is to keep colon as
empty as possible; starts with stool softener (higher dose); follows with retrograde enemas (advantage of retrograde enemas
is avoidance of surgery; disadvantage is enemas have large psychologic impact); antegrade cecal enemas used primarily
for those who fail retrograde enemas (response rate high; excellent as monotherapy; disadvantage is requirement
of surgical conduit into cecum for delivery)
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| VUR: ARGUMENTS FOR MEDICAL MANAGEMENT —Richard S. Hurwitz, MD, Pediatric Urologist, Kaiser Permanente,
Los Angeles
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| Introductory remarks: overall incidence of VUR in children 1%; however, incidence in children who present with febrile
UTIs about 30% to 50%; primary reflux related to anatomic abnormality at uretovesical junction; secondary reflux usually
due to voiding dysfunction or some form of anatomic obstruction; spontaneous resolution of VUR can occur, especially
in lower and middle grades; reflux harmless in absence of infection or obstruction; main concern is that reflux
allows infected urine to reach kidney and cause pyelonephritis; other complications associated with VUR, ie, hypertension,
end-stage renal disease, pregnancy complications, relatively rare
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| Medical management: based on rationale that sterile VUR is harmless, and that there is chance for spontaneous resolution;
daily therapy program consists of low-dose antibiotics, treatment of voiding dysfunction, and treatment of constipation;
followed by yearly imaging studies (usually VCUG, ultrasonography, and, sometimes, follow-up DMSA renal scan)
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| Comments: “classic” indications for surgical correction of VUR high-grade, persistent VUR, breakthrough febrile infections,
failure of medical management, and parental desire to end medical therapy; there has been a tremendous altering
and widening of options, with endoscopic treatment overlapping medical treatment, and also leading to much earlier correction
in virtually all grades of VUR (attractive option, as it can eliminate repeat VCUGs, antibiotic therapy, and prolonged
follow up, but not always needed)
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| Negative aspects of treatment options: medical therapy—need for antibiotics; breakthrough infections can occur; uncertain
resolution time; children hate VCUGs; endoscopic therapy—anesthetic complications can occur; failure rate 20%-
30%; durability has been questioned; surgical correction—children do well, but major procedure that involves hospitalization,
discomfort, and recovery from incision
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| Speaker’s position: let children outgrow VUR, “as long as they have a reasonable chance”; initial approach is medical
management for grades I-IV; happy to follow children with grades I and II long term, as long as they continue to do well;
in children with grade III or IV VUR, discusses correction (endoscopic therapy vs open surgery) if there is no resolution
after several years
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| Success rate with endoscopic therapy: significant learning curve (requires considerable experience to reach even 80% correction;
takes “great deal of skill” to achieve 90% correction); at speaker’s institution, overall success rate 78% (most
cases grade III VUR); cure rate 74% with unilateral endoscopic therapy, 61% with bilateral endoscopic correction; question
of open surgery for failed endoscopic treatment (different if Deflux injected outside or inside ureter)
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| Conclusions: aim of VUR treatment to prevent development and progression of renal scarring; task to identify children at
risk for developing renal damage (also to identify children who will remain at low risk if left untreated); period of medical
management important to help sort this out; recommends resisting correction of VUR initially, particularly in low-risk patients
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Educational Objectives
| The goal of this activity is to provide listeners with a better understanding of some of the challenges of pediatric urology,
with a focus on new concepts and approaches in the management of dysfunctional elimination, urinary tract infection
(UTI), and vesicoureteral reflux (VUR); the treatment of constipation as it relates to voiding dysfunction; and a consideration
of the medical management of VUR. After hearing and assimilating this program, the clinician will be better able to:
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 | 1. Establish a clinical diagnosis of UTI in infants and children.
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| 2. Explain the interaction of dysfunctional elimination problems, UTIs and VUR, and the importance of treating voiding
dysfunction in patients who present with UTI or VUR.
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| 3. Cite the advantages and efficacy of endoscopic injection, and consider its use in the treatment of VUR.
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| 4. Discuss pediatric constipation with parents and enlist them in the effective management of their child’s fecal retention
problem.
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| 5. Describe the rationale and possible indications for medical management of VUR.
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Discussed on This Program
Dextranomer/hyaluronic acid [Deflux]
Milk of magnesia [Concentrated Phillips’ Milk of Magnesia, Phillips’ Chewable, Phillips’ Milk of Magnesia] 1/5/07
Mineral oil [Kondremul Plain, Milkinol]
Nitrofurantoin macrocrystals [Macrobid, Macrodantin]
Polyethylene glycol solution [MiraLax]
Prunes
Psyllium [Fiberall, Genfiber, Hydrocil Instant, Konsyl, Konsyl-D, Konsyl Easy Mix Formula, Konsyl-Orange, Metamucil,
Modane Bulk, Natural Fiber Laxative, Perdiem Fiber Therapy, Reguloid, Serutan, Syllact]
Tegaserod maleate [Zelnorm]
Suggested Reading
Benninga MA et al: New treatment options in childhood constipation? J Pediatr Gastroenterol Nutr 41 Suppl 1:S56,
2005; Biggs WS, Dery WH: Evaluation and treatment of constipation in infants and children. Am Fam Physician 73:469,
2006; Bower WF et al: Dysfunctional elimination symptoms in childhood and adulthood. J Urol 174:1623, 2005; Canning
DA: Deflux for vesicoureteral reflux: pro--the case for endoscopic correction. Urology 68:239, 2006; Chen JJ et al: A
multivariate analysis of dysfunctional elimination syndrome, and its relationships with gender, urinary tract infection and
vesicoureteral reflux in children. J Urol 171:1907, 2004; Elder JS et al: Pediatric Vesicoureteral Reflux Guidelines Panel
summary report on the management of primary vesicoureteral reflux in children. J Urol 157:1846, 1997; Erickson BA et
al: Polyethylene glycol 3350 for constipation in children with dysfunctional elimination. J Urol 170:1518, 2003; Feldman
AS, Bauer SB: Diagnosis and management of dysfunctional voiding. Curr Opin Pediatr 18:139, 2006; Greenbaum LA,
Mesrobian HG: Vesicoureteral reflux. Pediatr Clin North Am 53:413, 2006; Hoberman A et al: Imaging studies after a
first febrile urinary tract infection in young children. N Engl J Med 348:195, 2003; Koff SA et al: The relationship among
dysfunctional elimination syndromes, primary vesicoureteral reflux and urinary tract infections in children. J Urol
160:1019, 1998; Lavelle MT, Conlin MJ, Skoog SJ: Subureteral injection of Deflux for correction of reflux: analysis of
factors predicting success. Urology 65:564, 2005; Loening-Baucke V, Pashankar DS: A randomized, prospective, comparison
study of polyethylene glycol 3350 without electrolytes and milk of magnesia for children with constipation and fecal
incontinence. Pediatrics 118:528, 2006; Maringhini S et al: Controversies in the antimicrobial treatment of urinary
tract infections. J Chemother 3:16-20, 2006; McCollough M, Sharieff GQ: Abdominal pain in children. Pediatr Clin
North Am 53:107, 2006; Mingin GC et al: Children with a febrile urinary tract infection and a negative radiologic workup:
factors predictive of recurrence. Urology 63:562, 2004; Pakarinen MP et al: Functional fecal soiling without constipation,
organic cause or neuropsychiatric disorders? J Pediatr Gastroenterol Nutr 43:206, 2006; Piccoli GB et al: Antibiotic
treatment for acute 'uncomplicated' or 'primary' pyelonephritis: a systematic, 'semantic revision'. Int J Antimicrob Agents
Suppl 1:S49, 2006; Reid H, Bahar RJ: Treatment of encopresis and chronic constipation in young children: clinical results
from interactive parent-child guidance. Clin Pediatr (Phila) 45:157, 2006; Rubin G, Dale A: Chronic constipation in children.
BMJ 333:1051, 2006; Setty R, Wershil BK: In brief: fecal overflow incontinence. Pediatr Rev 27:e54, 2006; Shaikh
N et al: Dysfunctional elimination syndrome: is it related to urinary tract infection or vesicoureteral reflux diagnosed early
in life? Pediatrics 112:1134, 2003; Silva JM et al: Clinical course of 735 children and adolescents with primary vesicoureteral
reflux. Pediatr Nephrol 21:981, 2006; Silva JM et al: Predictive factors of resolution of primary vesico-ureteric
reflux: a multivariate analysis. BJU Int 97:1063, 2006; Voskuijl WP et al: New insight into rectal function in pediatric defecation
disorders: disturbed rectal compliance is an essential mechanism in pediatric constipation. J Pediatr 148:62, 2006.
Faculty Disclosure
In adherence to ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant financial
relationship with the manufacturer or provider of any commercial product or service discussed. The following has been disclosed:
Dr. Hurwitz is a member of the Medical Advisory Board of Q-Med Scandinavia, Inc.
Drs. Skoog, Watanabe, and Hurwitz were recorded at the Southern California Permanente Medical Group 2006 Urology
Symposium, held September 15-17, 2006, in Los Angeles. The Audio-Digest Foundation thanks the speakers and the
Southern California Permanente Medical Group for their cooperation in the production of this program.
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