Neurogenic lower urinary tract dysfunction (NLUTD), previously termed neurogenic bladder dysfunction, is a common secondary complication of spinal cord injury (SCI). It is associated with significant morbidity, reduced quality of life, increased health care costs, and mortality. Primary care providers (PCPs) play an important role in optimizing urohealth over the life span. This article will review NLUTD in SCI, its complication, surveillance, and management. PCPs should be aware of SCI-related NLUTD, its complications, management, and surveillance recommendations, and when to refer to a specialist.
Regularly review patient’s bladder care/program (at least annually)
Annual creatinine to assess renal function
Renal ultrasound to assess upper tracts every 1–2 years
Urodynamics at baseline and when change in function (urinary tract infections, incontinence, difficulty catheterizing, autonomic dysreflexia, stones)
Consider cystoscopy in patients with long-term indwelling catheters due to increased prevalence of bladder cancer
Asymptomatic bacteriuria is very common. To avoid overtreatment and antibiotic resistance, do not perform routine urinalysis and culture in those without symptoms.
Symptoms of UTI may be atypical in people with SCI (autonomic dysreflexia, increased spasticity, change in frequency/incontinence, fever, abdominal discomfort, malaise).
Presence of signs and symptoms of UTI with urine culture findings (leukocyturia and positive urine culture) is the gold standard for guiding management in symptomatic UTI.
Paul is a 24-year-old with a T8 American Spinal Injury Association Impairment Scale (AIS) A spinal cord injury (SCI) sustained 5 years ago. He presents to his primary care provider (PCP) “feeling unwell,” with cloudy urine and increased spasticity. He reports that when he has these symptoms he has a urinary tract infection (UTI) and needs antibiotics. He tells you that he has received antibiotics three times in the past 9 months. He performs clean intermittent self-catheterization every 6 hours. He sometimes has incontinence between catheterizations. His blood pressure is 106/70 mm Hg (normal for him), heart rate 74 beats per minute, and temperature 37.0°C. He is not in distress.
PCPs and other health providers face uncertainty about neurogenic lower urinary tract dysfunction (NLUTD) in SCI and its complications such as UTI due to the complexity of the condition and lack of clear evidence-based guidelines.1,2 The goal of this article is to provide insight into SCI-related NLUTD and its management.
For individuals with SCI, NLUTD and UTI are common secondary complications that result in significant morbidity and can greatly affect quality of life.1,3 They are also associated with significant health care system costs due to preventable emergency department visits and hospitalizations.2,4,5 The vast majority of individuals with SCI experience bladder dysfunction.6–8 Even those who are ambulatory with incomplete SCI may have abnormalities in bladder function.8
Prevention of upper urinary tract deterioration (eg, hydroureter/hydronephrosis, renal failure)
Maintenance of continence
Preservation of quality of life
Prevention or early recognition and management of symptomatic UTI and secondary complications
During normal volitional voiding, the neurologically intact bladder, specifically the detrusor muscle, contracts and the external sphincter simultaneously relaxes allowing urine to pass. In NLUTD, the control and coordination of this normal process can be interrupted. There can, however, be great variance in presentation of the bladder dysfunction across patients.1,9,10
There are two main types of dysfunction associated with a neurogenic bladder after SCI: (1) a failure to store urine, and (2) a failure to empty the bladder of urine.10 Neurogenic detrusor overactivity (NDO), also referred to as hyperreflexic or spastic bladder, is a failure to store urine. NDO occurs with a spinal lesion at L1 or above. Increased storage pressure caused by uncoordinated contractions and relaxation of the detrusor and external sphincter can result in detrusor sphincter dysynergia (DSD). This can cause excessively increased intravesicular pressure. Complications can include incontinence, incomplete emptying, bladder thickening, renal stones, UTIs, hydroureter/nephrosis, and renal failure.
Areflexic bladder or flaccid bladder is a failure to empty the bladder and is caused by detrusor underactivity. It can occur with spinal lesions below L1, including a portion of those with cauda equina injuries. The loss of contractility in the detrusor and normal or decreased external sphincter tone can result in bladder overdistension and incontinence.
Methods of Managing NLUTD
Clean intermittent catheterization
Clean intermittent catheterization (CIC) involves periodic catheterization by the individual or another party usually four to six times per day. CIC is often considered the preferred method as it may have the lowest risk of symptomatic UTIs and long-term complications.1,3,10–12 Successful CIC requires appropriate hand dexterity.10,11 Furthermore, the cost of catheters can be a barrier that may lead many individuals to re-use catheters.10 In those performing intermittent catheterization, there is some evidence that hydrophilic-coated (a polymer coating that reduces friction and inflammation) catheters may reduce UTIs compared to noncoated catheters.1,2,12
Indwelling catheterization includes urethral and suprapubic catheters. These may be chosen if CIC cannot be consistently and reliably performed by the patient or caregiver.8 Suprapubic catheters, unlike urethral catheters, bypass the issues of catheter-related urethral damage and disruptions to sexual activity.10,11 Indwelling catheters are associated with higher rates of complications (eg, UTIs, calculi).3,10–12 There are inconclusive data regarding recommended frequency of catheter replacement; typically most are changed every 2 to 4 weeks.2
Condom catheters/external catheters can be used in select patients who rely on spontaneous detrusor contractility for “reflex voiding.” Urodynamic testing should ensure that bladder pressures are not dangerously high prior to use. Complications can include the condom falling off, skin irritation, incomplete emptying, and UTIs.10
Assisted bladder emptying
Assisted bladder emptying involves techniques such as Credé maneuvers, Valsalva maneuver, or triggered reflex voiding using suprapubic pressure to assist voiding. These strategies are generally discouraged as they can induce high bladder pressures, affect the pelvic floor musculature, and cause UTIs.3,10
Common pharmacologic methods to assist bladder function include the use of anticholinergic agents to promote detrusor relaxation, increase the capacity of a hyperactive detrusor muscle, and promote improved urine storage (Table 1 ).13,14 They are used in both intermittent and indwelling catheter users.3,8,15 Botulinum toxin A injections into the detrusor muscle can be recommended when anticholinergic agents are insufficient or cause intractable side effects.3,10
Alpha-adrenergic antagonists, or alpha-blockers, may be used when there is a need to decrease outlet resistance and aid in bladder emptying.3,8,10 Botulinum toxin injections into the external sphincter can also improve voiding.2,10 It should be noted that botulinum toxin has a temporary effect of approximately 3 to 4 months, and repeated treatments are often necessary. It is important to consider the possible side effects with each class of medications and how they might affect other aspects of care such as bowel function.3 These medications should be prescribed by clinicians experienced in their use and familiar with their potential side effects in SCI.
Urohealth Monitoring in NLUTD
Complications of NLUTD such as UTI, renal and bladder calculi, upper tract dysfunction (hydroureter/hydronephrosis), renal failure, bladder distension or thickening, strictures, and urethral trauma cause significant morbidity and mortality.1,3,10 The literature suggests an increased risk of bladder cancer in SCI patients with long-term catheters, however there is recent debate about this risk.1,17
The rate of mortality due to renal failure has decreased with regular surveillance, however there is no consensus to optimal frequency of urological testing.1,3,7,16,18 Commonly used screening tests include urodynamics, renal imaging, and blood tests. They are used to assess risk factors associated with the aforementioned complications. Recommendations for urohealth screening are detailed in Table 2 . In some regions (Veterans Health Administration in the United States), an annual comprehensive physical examination is offered to all individuals with SCI.19
A urology referral should be considered in all patients with neurogenic bladder.1 Absolute indications for urology referral include:
three or more UTIs per year,
upper tract dysfunction or presence of chronic kidney disease,
urethral trauma, and
ineffective current bladder management.
Urinary Tract Infection
UTIs, as defined by a presence of signs and/or symptoms of UTI with laboratory findings of a UTI (bacteriuria, leukocyturia, and positive urine culture), are a common complication associated with NLUTD.1,3,8,10,12,20 They are important to identify and treat as they are a risk for autonomic dysreflexia, renal complications, unnecessary hospital visits, and mortality.1,3,4 However, there is no clear consensus regarding the diagnosis of UTI in persons with NLUTD.1–3,12 Furthermore, asymptomatic bacteriuria is very common in SCI-related NLUTD, and avoidance of overtesting and treating asymptomatic bacteriuria is critical to avoid antibiotic resistance.1–3,10,21–23 Identifying symptomatic UTIs is challenging for most clinicians in the setting of NLUTD.
Figure 1 defines significant bacteriuria and outlines an office approach to diagnosis and management of symptomatic UTI. However, several factors challenge the ability to distinguish clinically significant UTI from asymptomatic bacteriuria in the context of SCI. Many individuals after SCI will have altered sensation and thus have atypical signs and symptoms.1,3,13,24 As mentioned, bacteriuria is common and impacts the interpretation of results as individuals will commonly have positive urine cultures.1–3,10,25 PCPs face pressure to treat UTIs given the inability of individuals with SCI to accurately predict when they have a UTI, challenges in obtaining a timely urine sample and culture, and fear of a serious infection.10,12,25 Clinicians and patients have a shared responsibility to avoid overtesting and overtreating asymptomatic bacteriuria. Studies in catheter-associated UTIs from asymptomatic bacteriuria within non-SCI populations may be useful in developing improved diagnostic approaches and algorithms for managing UTIs among individuals with SCI.26–28
Obtaining a urine sample for culture and antibiotic sensitivity is the gold standard in an individual who presents with signs and symptoms that may reflect a UTI.1–3,8,10,11,24 A urine sample can be refrigerated for up to 24 hours without affecting the result, thereby assisting in the challenge of obtaining a timely culture.10 The use of urine dipstick testing is controversial but can be useful to exclude a UTI if both nitrites and leukocytes are negative.10,24
UTIs that occur in NLUTD are considered complicated UTIs, and antibiotic treatment of 7 to 14 days is often recommended.1–3,12,16 Treatment should be based on culture and sensitivities; however, if prompt treatment is required, then individual and local antibiotic resistance characteristics should be considered.3
Prevention of UTI
A recent study by Kennelly et al12 has described a risk factor model for UTIs in individuals with NLUTD performing IC, identifying four areas that increase risk: general conditions (eg, high intravesical pressures and impaired bladder compliance, host deficiencies, or bowel dysfunction), local urinary tract conditions (eg. bacterial virulence, previous UTIs), user compliance/adherence (eg, non-hygienic practices, frequency, or fluids), and intermittent catheters (eg, catheterization introduces pathogens, catheter-associated trauma, or postvoid residual). Managing these risk factors may help reduce UTIs.
There is lack of evidence for interventions such as cranberry juice in UTI prevention.1–3,10 Long-term antibiotic prophylaxis is generally not successful and is discouraged to avoid antibiotic resistance.12,25 It should only be considered on an individual basis by a specialist.2,3 Since the presence of an indwelling catheter increases risk, the Infectious Disease Society of America (ISDA) suggests that indwelling catheters should be used only when indicated.2 Generally, indwelling catheters are not recommended for bladder voiding in individuals with SCI unless self-catheterization is unachievable. Such scenarios may present for individuals with high-level tetraplegia or for individuals with structural urethral abnormalities.29
Further assessment indicates that Paul may be constipated, and you wonder if this may be related to his feeling of malaise and reported spasticity. You advise changes to his bowel program. You advise that you will collect a urine sample but will not treat unless it shows an infection and symptoms do not improve. On his follow-up visit, Paul’s urine culture is nonconclusive showing “mixed growth,” and Paul reports he is feeling better since improving his constipation. You review his voiding program and discuss the approach to diagnosing UTIs and avoiding overtreatment. You give him an ultrasound requisition, bloodwork for creatinine, and referral to a urologist for further assessment as these have not been repeated since Paul sustained his injury.
NLUTD affects quality of life and can cause many preventable secondary complications. PCPs should have an understanding of the prevention, management, and treatment of NLUTD and its complications after SCI.
Key Take Home Points
Goals of neurogenic lower urinary tract dysfunction management are prevention of upper urinary tract deterioration (hydroureter/hydronephrosis, renal failure), maintenance of continence, preservation of quality of life, prevention or early recognition of symptomatic urinary tract infection and secondary complications.
Dr. Kennelly reports consulting with Allergan, Astellas, Boston Scientific, Bard, and Cogentix and receiving study grants from Allergan, Amphora, Cook Myosite, and Ipsen outside the submitted work. The other authors report no conflicts of interest.