Campbell-Walsh Urology, 11th Edition

PART XV

Pediatric Urology

SECTION D

Lower Urinary Tract Conditions

142

Neuromuscular Dysfunction of the Lower Urinary Tract in Children

Dawn Lee MacLellan; Stuart B. Bauer

Questions

1. Which of the following is an acquired form of neuromuscular dysfunction of the lower urinary tract?
2. Myelomeningocele
3. Cerebral palsy
4. Lipomeningocele
5. Sacral agenesis
6. Anorectal malformation
7. What is the primary goal in management of neuromuscular dysfunction of the lower urinary tract?
8. Achievement of urinary continence
9. Achievement of fecal continence
10. Preservation of renal function
11. Facilitation of sexual function
12. Avoidance of urinary tract infection
13. The International Children's Continence Society (ICCS) recommends more frequent evaluation of children during periods of high rates of somatic growth when spinal cord tethering is more likely. These two development periods are:
14. Newborn to toddler AND toddler to adolescent
15. Newborn to toddler AND adolescent to adult
16. Newborn to toddler AND adulthood
17. Toddler to adolescent AND adolescent to adult
18. Toddler to adolescent AND adulthood
19. The International Children's Continence Society's indications for repeat investigations before the routinely scheduled follow-up for neuromuscular dysfunction of the lower urinary tract do NOT include:
20. urinary tract infections.
21. development or worsening of hydronephrosis.
22. worsening continence.
23. change in lower extremity function.
24. improved continence.
25. Which of the following may compromise bladder emptying in neuromuscular dysfunction of the lower urinary tract?
26. Low capacity
27. Low compliance
28. Detrusor overactivity
29. Detrusor sphincter dyssynergia
30. Low outlet resistance
31. Initial minimally invasive treatment options to address inadequate bladder storage in neuromuscular dysfunction in children usually involve:
32. overnight indwelling catheter drainage.
33. antimuscarinics and clean intermittent catheterization.
34. percutaneous cystostomy tube.
35. endoscopic injection of botulinum toxin.
36. robotic assisted augmentation cystoplasty.
37. The use of antimuscarinics for the treatment of detrusor overactivity in children does NOT result in the following:
38. increased bladder capacity.
39. decreased number of bladder contractions.
40. decreased number of incontinence episodes.
41. decreased number of catheterizations.
42. decreased volume to first bladder contraction.
43. A possible predictor of poor clinical response to intravesical injection of botulinum toxin injection is preexisting:
44. low maximum cystometric capacity.
45. detrusor overactivity.
46. more than five episodes of incontinence per day.
47. poor detrusor compliance.
48. previous botulinum toxin injections.
49. Which of the following increases the risk of developing lower urinary tract stones in children with bladder augmentation?
50. Use of the ileal segment
51. Routine bladder irrigation with water or saline
52. Use of an antimuscarinic
53. Catheterization of the urethra, rather than an abdominal stoma
54. A mobile patient
55. The presentation of bladder malignancy in those with a history of bladder augmentation does NOT include:
56. Presenting with advanced disease.
57. Presenting at an older age than is typical for bladder malignancies.
58. Presenting with atypical symptoms, such as vague abdominal pain, urosepsis or increased frequency of urinary tract infection (UTI), difficult catheterization, and renal failure.
59. Presenting with a time lag of a minimum of 10 years after a bladder augmentation.
60. Presenting with atypical signs, such as new hydronephrosis and bladder wall thickening.
61. Which of the following is the preferred approach to increase bladder capacity in children with neuromuscular dysfunction of the lower urinary tract?
62. Autoaugmentation
63. Enteric augmentation with a gastric segment
64. Tissue-engineered bladder substitute
65. Enteric augmentation with an ileal segment
66. Enteric augmentation with an ileal-cecal segment
67. Worsening of bladder function after isolated bladder neck procedures including implantation of an artificial urinary sphincter or bladder neck fascial sling is more common in those with:
68. preexisting detrusor overactivity and poor compliance.
69. preexisting low maximum cystometric capacity.
70. surgery in the postpubertal period.
71. detrusor sphincter dyssynergia.
72. history of prior bladder neck outlet procedures.
73. Which of the following is NOT an acceptable method of managing high-grade vesicoureteral reflux in children with neuromuscular dysfunction of the lower urinary tract?
74. Clean intermittent catheterization
75. Antimuscarinics
76. Antibiotic prophylaxis
77. Ureteral re-implantation
78. Bladder emptying by the Credé maneuver
79. Prenatal surgery for children with myelomeningocele compared with standard postnatal closure has been noted to result in:
80. an increased risk of fetal death and need for cerebrospinal fluid shunting.
81. worsening of mental development and motor function at 30 months.
82. fewer pregnancy complications.
83. a lower risk of preterm labor.
84. no improvement in bladder function.
85. Indications for the initiation of clean intermittent catheterization in the newborn with myelomeningocele do NOT include:
86. postvoid residual urine measurement of 3 mL after the Credé maneuver.
87. postvoid residual urine measurement of 10 mL after spontaneous voiding.
88. the presence of detrusor sphincter dyssynergia on urodynamic studies.
89. the presence of hydronephrosis and high-grade vesicoureteral reflux with poor bladder emptying.
90. poor bladder compliance with bladder filling pressures greater than 40 cm H₂O.
91. The highest risk for the development of urinary tract deterioration in children with myelodysplasia is in those with initial urodynamic findings of:
92. detrusor sphincter synergy.
93. detrusor sphincter dyssynergy.
94. complete denervation.
95. low maximum cystometric capacity.
96. detrusor overactivity.
97. The gold standard for measuring renal function in children with myelodysplasia is:
98. serum creatinine.
99. glomerular filtration rate as estimated by the Schwarz formula.
100. glomerular filtration rate as estimated by the Modification of Diet in Renal Disease (MDRD) equation.
101. serum cystatin C.
102. nuclear renography.
103. Sexual function and satisfaction in men with myelomeningocele is better with the following condition:
104. living with their parents.
105. severe incontinence.
106. a sacral-level lesion of the neural tube defect.
107. a thoracic-level lesion of the neural tube defect.
108. the presence of hydrocephalus.
109. The most common finding associated with an occult neural tube defect is:
110. a cutaneous abnormality overlying the lower spine.
111. high-arched feet.
112. claw or hammer toes.
113. abnormal gait.
114. absent perineal sensation.
115. In a 1-year-old child, definitive diagnosis of an occult neural tube defect is best made by:
116. Spinal ultrasound.
117. Urodynamic studies demonstrating findings consistent with neurogenic bladder dysfunction.
118. Magnetic resonance imaging of the spine.
119. Documentation of resolution of abnormal urodynamic findings after a detethering procedure.
120. Abnormal electromyography of the external urinary sphincter.
121. Which of the following is UNLIKELY to be noted in a child with neuromuscular dysfunction of the lower urinary tract secondary to sacral agenesis?
122. Urinary incontinence
123. A maternal history of diabetes mellitus or gestational diabetes
124. Flattened buttocks and a short, low gluteal cleft
125. Absent perineal sensation
126. Vesicoureteral reflux and recurrent urinary tract infections
127. Urodynamic studies of children with an anorectal malformation should be performed in all of the following circumstances EXCEPT:
128. a bony malformation of the spine or a spinal cord defect.
129. hydronephrosis.
130. vesicoureteral reflux.
131. urinary or fecal incontinence.
132. a low insertion of the fistulous site.
133. Which of the following statements concerning bladder function in children with cerebral palsy is TRUE?
134. They achieve nighttime urinary continence first.
135. They achieve urinary continence at the same age as their age-adjusted peers.
136. Lower urinary tract symptoms are more common in younger children.
137. The most common urinary tract symptom is monosymptomatic nocturnal enuresis.
138. Clinical symptoms of recurrent UTI and detrusor sphincter dyssynergia (retention, interrupted stream, and hesitancy) are associated with upper urinary tract deterioration.
139. The most common presenting urinary symptom in children with transverse myelitis is:
140. urinary incontinence.
141. urinary tract infection.
142. urinary retention.
143. urinary frequency.
144. urinary urgency.

Answers

1. b. Cerebral palsy.Cerebral palsy is the only acquired disease process in the list. The remainder are congenital.
2. c. Preservation of renal function. Although the other listed goals have important clinical and social implications, preservation of renal function is the primary goal of treatment.Achievement of urinary/fecal continence, sexual function, and avoidance of urinary tract infection are secondary goals of treatment.
3. b. Newborn to toddler AND adolescent to adult.The correct combination of growth periods in which the rate of somatic growth is highest is in the newborn to toddler and adolescent to adult age group. This recommendation is due to the fact that the highest rate of spinal cord tethering, and thus change in bladder/bowel function, is during periods of highest somatic growth.
4. e. Improved continence.Urinary tract infections, hydronephrosis, worsening continence, and a change in lower extremity function are more likely to indicate a significant change in bladder function than improved continence.
5. d. Detrusor sphincter dyssynergia.Detrusor sphincter dyssynergia is the only entity listed that may compromise bladder emptying. All other listed options would facilitate or encourage early bladder emptying.
6. b. Antimuscarinics and clean intermittent catheterization.The beneficial effects of early initiation of antimuscarinics and clean intermittent catheterization are well established. The other listed options would be considered to be more invasive or less established methods of intervention.
7. e. Decreased volume to first bladder contraction. Antimuscarinics in children result in increased bladder capacity, fewer bladder contractions, less incontinence, and fewer catheterizations.The question is worded negatively, so answer e is correct, because antimuscarinics would be expected to increase the volume to first bladder contraction, rather than decrease it.
8. d.Poor detrusor compliance. Kask et al (2013)* demonstrated that preexisting poor detrusor compliance predicts a poor clinical response to intravesical injection of botulinum toxin. One could postulate that the histologic changes that are present after the development of poor detrusor compliance are not amenable to the effects of botulinum toxin.
9. a. Use of the ileal segment.The use of an ileal segment has been shown to increase the risk of lower urinary tract stones. Catheterization through the urethra, rather than via an abdominal stoma, is associated with fewer lower urinary tract stones, presumably because of better drainage. A mobile patient and routine bladder irrigation decrease the risk of stones. The use of an antimuscarinic should not affect stone formation.
10. b. Presenting at an older age than is typical for bladder malignancies. Those with bladder augmentation present at a younger age, with atypical symptoms and advanced disease, usually with a minimum 10-year lag time between augmentation and presentation of bladder malignancy.
11. d. Enteric augmentation with an ileal segment. Lack of improvement in urodynamic and clinical symptoms, along with a high failure rate, makes autoaugmentation an undesirable option. Gastric segments are associated with more symptomatic side effects (such as hematuria dysuria syndrome) and metabolic complications than ileal segments. It is recommended to avoid the ileal-cecal segment in children with neural tube defects because it may aggravate bowel dysfunction.Phase II studies of tissue-engineered bladder revealed no improvement in urodynamic parameters and serious adverse events. Thus, the ileal segment is the most desirable for enteric augmentation.
12. a. Preexisting detrusor overactivity and poor compliance.Isolated bladder neck procedures, such as artificial urinary sphincter and bladder neck repairs, have been noted to lead to worsening of bladder function in as many as 30% of patients, especially those with preexisting detrusor overactivity and poor compliance. The remaining answers have not been associated with worsening of bladder function after isolated bladder neck procedures.
13. e. Bladder emptying by the Credé maneuver.Children with a reactive external urinary sphincter will have a reflex response of increased external urethral tone in response to the Credé maneuver, which can aggravate reflux and thus is contraindicated in this group. The other listed options are all reasonable methods of managing vesicoureteral reflux in those with neuromuscular dysfunction of the lower urinary tract.
14. e. No improvement in bladder function. Prenatal surgery for children with myelomeningocele compared with standard postnatal closure has been noted to decrease the need for cerebrospinal fluid shunting, improve neuromotor function, and increase pregnancy complications and the risk for preterm labor.The correct answer is there is no improvement in lower urinary tract function with prenatal versus postnatal closure.
15. a. Postvoid residual urine measurement of 3 mL after the Credé maneuver.A postvoid residual urine measurement of 3 mL after the Credé maneuver is within normal limits and does not require the initiation of clean intermittent catheterization (CIC). All other possible answers are indications for the initiation of CIC.
16. b. Detrusor sphincter dyssynergy. Within the first 3 years of life, more than 70% of children with detrusor sphincter dyssynergy will have urinary tract deterioration, whereas less than one quarter of those with synergy or complete denervation will have deterioration.Low maximum cystometric capacity and detrusor overactivity have not been associated with upper tract deterioration.
17. e. Nuclear renography.Although all possible answers are means of measuring renal function in children with myelodysplasia, nuclear renography is considered to be the gold standard.
18. c. A sacral-level lesion of the neural tube defect.Lesions above the sacral spinal cord, hydrocephalus, incontinence, and living with parents are associated with less sexual function and satisfaction compared with men with a sacral-level lesion.
19. a. A cutaneous abnormality overlying the lower spine. A cutaneous abnormality overlying the spine, such as a skin dimple, tuft of hair, skin tag, lipoma, vascular malformation, or asymmetric gluteal cleft, is noted in 90% of those with occult neural tube defect.The other listed answers are also noted in this entity, but their occurrence is much less frequent.
20. c. Magnetic resonance imaging of the spine.Spinal ultrasound may be used before ossification of vertebral bones (3 months of age). After this time, magnetic resonance imaging of the spine is required for definitive diagnosis of an occult neural tube defect.
21. d. Absent perineal sensation.Children with sacral agenesis have normal perineal sensation, thus d is incorrect. The remaining answers may be found in patients with sacral agenesis.
22. e. A low insertion of the fistulous site.Urodynamic evaluation in those with anorectal malformation is indicated if there is suggestion of possible spinal cord tethering (bony malformation of the spine or spinal cord defect) or signs and/or symptoms that might indicate a neurogenic defect such as hydronephrosis, vesicoureteral reflux, or urinary/fecal incontinence. Although spinal cord defects may be present in as many as a third of those with a low insertion of the fistula site, a low insertion site itself is not an indication for urodynamic study.
23. e. Clinical symptoms of recurrent UTI and detrusor sphincter dyssynergia (retention, interrupted stream, and hesitancy) are associated with upper urinary tract deterioration. Children with cerebral palsy usually achieve daytime dryness first, at an older age than their age-adjusted peers. Lower urinary tract symptoms become more prevalent in children with cerebral palsy while they age. The most common symptom in these children is incontinence.Clinical symptoms of recurrent UTI and detrusor sphincter dyssynergia are associated with upper urinary tract deterioration and may warrant investigation with renal/bladder ultrasound and urodynamic studies.
24. c. Urinary retention.The most common presenting urinary symptom of transverse myelitis is urinary retention. Ninety-five percent of children in the acute phase of the disease will have urinary retention.

Chapter review

1. During urodynamics, bladder filling should occur at a rate of the calculated bladder capacity divided by 10 per minute.
2. Normal voiding pressure in boys is 55 to 80 cm H₂O, and in girls it is 30 to 65 cm H₂O.
3. In the myelomeningocele patient, the bony vertebral level provides little or no clue as to the neurologic level.
4. Upper motor neuron lesions result in an overactive detrusor, exaggerated sacral reflexes, detrusor sphincter dyssynergia, a thickened bladder wall, and a closed bladder neck.
5. Lower motor neuron lesions result in a noncontractile detrusor, denervation of the external sphincter, diminished or absent sacral reflexes, and a small smooth-walled bladder with an open bladder neck.
6. Assessment of the neonate with myelomeningocele involves renal ultrasonography and measurement of the postvoid residual urine.
7. Resting bladder pressure should be maintained below 30 cm H₂O. Resting pressures above 40 cm H₂O result in upper tract deterioration.
8. The neurologic lesion in myelodysplasia is a dynamic process and changes throughout childhood.
9. Bowel incontinence is frequently unpredictable and not associated with the attainment of urinary continence in myelodysplasia patients.
10. Sacral agenesis may result in bladder dysfunction not detected at birth and is usually brought to the physician's attention when the child fails at toilet training.
11. Sacral agenesis may manifest as either an upper or lower motor neuron lesion.
12. In patients with cerebral palsy, the presence of incontinence is usually related to the physical impairment.
13. In traumatic injuries of the spine, patients with upper thoracic and cervical lesions are likely to exhibit autonomic dysreflexia.
14. Women with low levels of folic acid or impairment of folic acid–mediated pathways are at increased risk for having a child with a neural tube defect.
15. Findings on initial urodynamic assessment warranting further investigation with a voiding cystourethrogram include detrusor overactivity, poor compliance, disorders of sex development, and elevated voiding pressure; moreover, reflux in myelodysplastic children is invariably associated with one of these abnormalities.
16. There are three categories of findings on urodynamics in myelodysplastic children: synergy, dyssynergia, and complete denervation.
17. Serum creatinine in myelodysplastic children is a poor predictor of renal function; serum cystatin C may be a better predictor.
18. In patients with neural tube defects, early intervention with CIC and antimuscarinics decreases UTIs, vesicoureteral reflux, upper tract deterioration, and the incidence of end-stage renal disease.
19. Puberty occurs as much as 2 years earlier in girls with myelodysplasia.
20. Indications for augmentation cystoplasty in patients with neural tube defects include poor bladder compliance, small capacity, and overactive detrusor.
21. Autoaugmentation is not effective in patients with myelodysplasia.
22. Occult spinal dysraphism in the newborn period may be suggested by a sacral defect or a cutaneous abnormality over the sacrum such as a skin dimple, tuft of hair, skin tag, lipoma, vascular malformation, or asymmetric gluteal cleft. Early detection and intervention addressing bladder dysfunction markedly improves renal and bladder outcomes.
23. Children of diabetic mothers are at increased risk for sacral agenesis.
24. In patients with anorectal malformations, a neurogenic bladder is usually associated with a spinal cord abnormality.
25. Children with cerebral palsy often achieve continence, although at a later date than their age matched peers.
26. The highest rate of spinal cord tethering, and thus a change in bladder/bowel function, is during periods of highest somatic growth.
27. Gastric segments used for augmentation cystoplasty are associated with more symptomatic side effects (such as hematuria dysuria syndrome) and metabolic complications than ileal segments. It is recommended to avoid the ileal-cecal segment in children with neural tube defects because it may aggravate bowel dysfunction.
28. Prenatal surgery for children with myelomeningocele compared with standard postnatal closure has been noted to decrease the need for cerebrospinal fluid shunting, improve neuromotor function, and increase pregnancy complications and the risk for preterm labor.
29. Within the first 3 years of life, more than 70% of children with detrusor sphincter dyssynergy will have urinary tract deterioration, whereas less than one quarter of those with synergy or complete denervation will have deterioration.

^* Sources referenced can be found in Campbell-Walsh Urology, 11th Edition, on the Expert Consult website.