Alana M. Murphy, MD
BASICS
DESCRIPTION
Neurogenic bladder (NGB) is a general term used to describe dysfunction of the urinary bladder due to disease of the central nervous system (CNS) or peripheral nerves involved in the control of urine storage and micturition
EPIDEMIOLOGY
Incidence
Difficult to determine incidence due to multiple etiologies
Prevalence
• Prevalence of voiding dysfunction by specific conditions:
– Cerebrovascular accident: 20–50%
– Parkinson disease: 35–70%
– Multiple sclerosis: 50–90%
– Diabetes mellitus: 5–60%
RISK FACTORS
• Neurologic disease, injury, or congenital malformation
• Diabetes mellitus
• Radical pelvic surgery
Genetics
Genetic diseases that may be associated with NGB include muscular dystrophy, hereditary spastic paraplegia, neurofibromatosis, and familial dysautonomia
PATHOPHYSIOLOGY
• CNS lesions (1):
– Suprapontine:
Function: Inhibits sacral micturition center
Detrusor overactivity (DO) due to loss of inhibition of sacral micturition center
– Pontine micturition center:
Function: Coordinates sphincter relaxation during bladder contraction
Lesions between pontine and sacral micturition centers are associated with DO and detrusor sphincter dyssynergia (DSD)
– Sacral micturition center:
Function: Mediates reflex and voluntary bladder contraction
Detrusor underactivity or acontractility
• Peripheral lesions (1): Variable voiding dysfunction
– Detrusor underactivity
– Impaired bladder sensation
– Impaired sphincteric function
ASSOCIATED CONDITIONS
• CNS diseases:
– Cerebrovascular accident
– Multiple sclerosis
– Normal-pressure hydrocephalus
– Parkinson disease
– Spinal cord injury
– Transverse myelitis
• Peripheral nerve disease:
– Following radical pelvic surgery:
Abdominoperineal resection
Radical hysterectomy
– Diabetes mellitus
– Intervertebral disk disease
– Spinal stenosis
– Guillain–Barré syndrome
• Neural tube defects
• Cerebral palsy
GENERAL PREVENTION
• Tight glycemic control with diabetes mellitus
• Prevention aimed at preventing secondary complications
– Infections
– Incontinence
– Skin breakdown
– Urolithiasis
DIAGNOSIS
HISTORY
• Neurologic disease: Onset, duration
• Diabetes mellitus
• Congenital disorders:
– Neural tube defects
– Cerebral palsy
• History of radical pelvic surgery
• Voiding symptoms
• Storage symptoms
– Urinary frequency
– Incontinence
• Method of urinary management:
– Volitional or reflex voiding
– Condom catheter urinary collection
– Intermittent self-catheterization
– Indwelling urethral or suprapubic catheter
– Credé or Valsalva voiding
• UTI:
– Severity of infection: Febrile, hospitalization, IV antibiotics required
– Frequency of recurrence
• Urolithiasis episodes, surgical intervention, calculus composition
• Autonomic dysreflexia (AD): Associated with spinal cord lesion at or above T6
– Occurs with manipulation of the urinary or gastrointestinal tract
PHYSICAL EXAM
• Flank tenderness: Ureteral obstruction, pyelonephritis
• Abdominal mass: Distended bladder, urinary retention
• Incontinence of urine:
• Testicular exam:
– Epididymo-orchitis/epididymitis; secondary abscess
• Digital rectal exam:
– Prostate size: BPH may coexist with NGB
– See neurologic exam
• Evaluate for sacral abnormalities:
– Sacral dimple, skin tag, discoloration or tuft of hair may suggest occult spinal dysraphism
– Sacral agenesis
• Focused neurologic exam:
– Sacral root
– Perianal sensation
– Anal tone, sphincter control
DIAGNOSTIC TESTS & INTERPRETATION
Lab
• Blood studies:
– Serum chemistry: Renal function, creatinine
– CBC: Elevated WBC, secondary anemia due to decreased renal function or chronic infection
• Urinalysis:
– Proteinuria: Renal dysfunction
– Pyuria, nitrite, leukocyte esterase: Acute or chronic infection
– Hematuria: Infection or urolithiasis
Imaging
• Imaging is most important in patients with risk factors for upper tract compromise:
– DSD (especially males who void reflexively)
– Impaired bladder compliance
• Renal ultrasound (US): To screen for calculus, hydronephrosis, or mass
• Excretory urography:
– Delayed excretion of contrast with high urinary storage pressures
– Hydroureteronephrosis:
Marked elevation of intravesical pressure or calculi
• Nuclear medicine renal scan:
– Assess for obstruction
– Sequential studies detect deterioration of renal function
Diagnostic Procedures/Surgery
• Urodynamics (UDS): Necessary to determine effective urologic management for all patients with neurogenic lower urinary tract dysfunction
• Neurogenic DO (NDO):
– Loss of CNS inhibition
• DSD (abnormal reflexive sphincter contraction during involuntary or voluntary detrusor contraction):
– Functional bladder outflow obstruction with elevated intravesical pressure
– Secondary damage: Pressure, infection, urolithiasis
– 10–20% of patients have internal (bladder neck) sphincter dyssynergia with external sphincter dyssynergia.
– Elevated intravesical pressure >40 cm H2O responsible for sequelae of NDO–DSD
• Detrusor underactivity or acontractility:
– Interruption of sacral reflex arc; no detrusor contraction
– Typically low-pressure storage
– Adrenergic overgrowth: May result in decreased bladder compliance, elevated storage pressure
Pathologic Findings
Bladder wall thickening with fibrosis and trabeculation
DIFFERENTIAL DIAGNOSIS
• Idiopathic overactive bladder
• Dysfunctional voiding
TREATMENT
GENERAL MEASURES (2)
• UDS is essential to determine lower urinary tract function/dysfunction and to plan urologic management.
• Maintaining low intravesical pressure protects upper urinary tracts
• Urinary drainage: Intermittent catheterization or external collection appliance
• Indwelling catheterization:
– Associated with recurrent UTIs, urethral erosion, urolithiasis
• Intermittent self-catheterization: Most effective treatment; requires low storage pressure
• Surgical intervention is indicated when other therapies fail to protect the upper urinary tract or provide continence.
MEDICATION
First Line
• Antimuscarinics aimed at decreasing urinary storage pressure and reducing NDO. Most common side effects include dry mouth and constipation
– Fesoterodine 4–8 mg QD
– Hyoscyamine extended release 0.375 mg BID
– Oxybutynin 5 mg BID-TID
– Oxybutynin transdermal patch 3.9 mg/d
– Oxybutynin XL 10–15 mg/d
– Oxybutynin, topical gel 10% apply 1 sachet QD to dry skin
– Solifenacin 5–10 mg/d
– Tolterodine LA 1–2 mg BID
– Tolterodine LA 2–4 mg/d
– Trospium XR 60 mg/d
• β 3-agonist: Most common side effects include an increase in blood pressure and palpitations
– Mirabegron 25 mg/d increase to 50 mg/d after 8 wk PRN
• α-Adrenergic blockers: Decrease internal sphincter resistance, lower voiding pressure; ineffective for DSD.
– Alfuzosin 10 mg/d
– Doxazosin start 1 mg/d to max 8 mg
– Silodosin 8 mg/d
– Tamsulosin start 0.4 mg to max 0.8 mg
– Terazosin start 1 mg/d to max 20 mg
Second Line
• Botulinum toxin type A (onabotulinumtoxinA) injection into the external sphincter for DSD
– Short-lived; requires repeat injections
• Botulinum toxin injection into the detrusor for NDO
– Duration of action is 3–9 mo
– Requires repeated injections
SURGERY/OTHER PROCEDURES
• Endoscopic sphincter ablation or stenting:
– Only males with DSD; requires condom catheter
• Augmentation cystoplasty using an intestinal segment to enlarge the bladder
– Goal is to increase bladder volume and decrease bladder pressure
– Intermittent catheterization for urinary drainage
– Limited dexterity mandates construction of a continent catheterizable stoma for the urinary reservoir, especially in females
• Ileovesicostomy
– Useful for those unable to perform self-catheterization (ie, quadriplegia)
• Cystectomy with continent urinary reservoir
– Ileal or colon pouch; continent catheterizable stoma (appendix or tapered ileum)
• Cystectomy with ileal conduit
ADDITIONAL TREATMENT
Radiation Therapy
N/A
Additional Therapies
Neuromodulation, sacral nerve stimulation and posterior tibial nerve stimulation are not FDA approved for the treatment of NDO but may have some benefit.
Complementary & Alternative Therapies
Acupuncture has been reported to improve symptoms of neurogenic bladder.
ONGOING CARE
PROGNOSIS
Proper urologic management greatly improves quality of life in patients with NGB dysfunction.
COMPLICATIONS
• Recurrent UTIs
• Urinary retention
• Hydroureteronephrosis
• Neoplastic transformation: Associated with chronic catheter
• Urethral erosion
FOLLOW-UP
Patient Monitoring
• Annual evaluation in high-risk patients may include (3):
– UDS
– Imaging: Typically renal US
– Serum creatinine
Patient Resources
• http://www.nationalmssociety.org
• http://www.spinalcord.org/
• http://www.parkinson.org/
REFERENCES
1. Fowler CJ, Dalton C, Panicker JN. Review of neurologic diseases for the urologist. Urol Clin North Am. 2010;37(4):517–526.
2. Abrams P, Agarwal M, Drake M, et al. A proposed guideline for the urological management of patients with spinal cord injury. BJU Int. 2008;101(8):989–994.
3. Ginsberg D, Gousse A, Keppenne V, et al. Phase 3 efficacy and tolerability study of onabotulinumtoxinA for urinary incontinence from neurogenic detrusor overactivity. J Urol. 2012;187(6):2131–2139.
ADDITIONAL READING
Tapia CI, Khalaf K, Berenson K, et al. Health-related quality of life and economic impact of urinary incontinence due to detrusor overactivity associated with a neurologic condition: a systematic review. Health Qual Life Outcomes.2013;11:13–28.
See Also (Topic, Algorithm, Media)
• Bladder Areflexia (Detrusor Areflexia)
• Detrusor Overactivity
• Detrusor Sphincter Dyssynergia (DSD)
• Incontinence, Urinary, Adult Female
• Incontinence, Urinary, Adult Male
• Incontinence, Urinary, Pediatric
• Neurogenic Detrusor Overactivity (NDO)
• Overactive Bladder
• Spinal Cord Injury, Urologic Considerations
• Stroke (CVA), Urologic Considerations
CODES
ICD9
• 596.51 Hypertonicity of bladder
• 596.54 Neurogenic bladder NOS
• 596.59 Other functional disorder of bladder
ICD10
• N31.8 Other neuromuscular dysfunction of bladder
• N31.9 Neuromuscular dysfunction of bladder, unspecified
• N32.81 Overactive bladder
CLINICAL/SURGICAL PEARLS
Adequate management of lower urinary tract function is essential to avoid upper urinary tract compromise and preservation of renal function.