What is the treatment for detrusor (detrusor muscle) sphincter dyssynergia?

Treatment of Detrusor Sphincter Dyssynergia

The primary treatment for detrusor sphincter dyssynergia is clean intermittent catheterization (CIC) combined with anticholinergic medications to relax the detrusor and protect the upper urinary tracts; for patients unable or unwilling to perform CIC, sphincterotomy with condom catheter drainage is the alternative, though it is irreversible. 1

First-Line Management: CIC + Anticholinergics

The cornerstone of DSD treatment prioritizes renal preservation by reducing high-pressure bladder storage:

• Clean intermittent catheterization should be initiated early (ideally before age 1 year in pediatric cases) to prevent renal cortical loss and upper tract deterioration 1
• Anticholinergic medications (antimuscarinics) are added to suppress involuntary detrusor contractions, ensuring continence between catheterizations and reducing storage pressures 1
• This combination addresses the fundamental problem: the detrusor contracts against a closed sphincter, creating dangerously high intravesical pressures that damage kidneys 1

Critical pitfall: Late initiation of CIC (after age 1 year) is an independent risk factor for renal scarring, even more so than hydronephrosis or urodynamic findings alone 1

Second-Line: Alpha-Blockers

When CIC with anticholinergics proves insufficient:

• Selective α-1 adrenergic antagonists (alpha-blockers) can be added to reduce bladder outlet resistance by relaxing smooth muscle at the bladder neck and urethra 1
• These facilitate bladder emptying by decreasing sphincter tone during voiding attempts 1
• Use remains off-label in children but shows encouraging results in adults and pediatric populations with incomplete emptying 1

Third-Line: Botulinum Toxin Injections

For patients refractory to oral medications:

• OnabotulinumtoxinA injection into the external urethral sphincter can reduce sphincter activity and lower detrusor pressures 1
• This approach is particularly useful in children when behavioral therapy and alpha-blockers have failed 1
• Major caveat: Urinary retention occurs in 20.49% of patients, necessitating discussion about potential need for CIC before treatment 1
• Patients who already perform CIC are ideal candidates since retention risk is already mitigated 1

Surgical Option: Sphincterotomy

External urethral sphincterotomy is reserved for male patients who cannot or refuse to perform CIC:

• This irreversible procedure facilitates bladder emptying, decreases UTIs, and preserves upper tract function 1
• Appropriate candidates include those with reflex voiding, poor hand function, or unwillingness to catheterize who can manage incontinence with condom catheters 1
• Counsel patients about high failure rates and potential need for additional surgery 1
• Post-sphincterotomy urodynamics should be performed to confirm reduction in storage pressures 1

Monitoring Requirements

Regular surveillance is essential to prevent renal deterioration:

• Perform urodynamic studies at appropriate intervals to assess treatment effectiveness and ensure storage pressures remain safe 1
• Monitor for upper tract changes with imaging, as 80% of expectantly managed DSD patients develop hydronephrosis 1
• Check post-void residuals and uroflowmetry to ensure adequate emptying 1

Treatment Algorithm Summary

1. Start with CIC + anticholinergics for all patients capable of catheterization 1
2. Add alpha-blockers if emptying remains inadequate despite CIC 1
3. Consider botulinum toxin for refractory cases, especially if already performing CIC 1
4. Reserve sphincterotomy for males unable/unwilling to perform CIC who accept permanent incontinence managed with external collection 1

The overarching goal is preventing renal damage from sustained high-pressure voiding, which occurs in over 50% of untreated DSD patients within 5 years 2. Every treatment decision must prioritize upper tract protection over continence or convenience.