What are the treatment options for a 7mm Pelvic Ureteric Junction (PUJ) stone?

Management of 7mm PUJ Stone

For a 7mm pelvic ureteric junction (PUJ) stone, both shock wave lithotripsy (SWL) and ureteroscopy (URS) are appropriate first-line treatment options, with URS offering higher stone-free rates and lower likelihood of requiring repeat procedures. 1

Initial Treatment Options

Medical Expulsive Therapy (MET)

• Alpha blockers (such as tamsulosin 0.4mg daily) can be used as initial management for stones ≤10mm 2
• Maximum observation period with MET should be 4-6 weeks to avoid irreversible kidney damage 2
• MET works by relaxing ureteral smooth muscle, potentially facilitating stone passage

Procedural Interventions

1. Shock Wave Lithotripsy (SWL)

   • Appropriate for 7mm PUJ stones (within the ≤20mm category) 1
   • Less invasive than URS
   • Stone-free rates of approximately 87% for stones <10mm 2
   • May require multiple sessions

2. Ureteroscopy with Laser Lithotripsy (URS)

   • Also appropriate for 7mm PUJ stones 1
   • Higher stone-free rates compared to SWL (evidence shows URS has a lower risk of requiring additional procedures) 1
   • Stone-free rates of 85-95% 2
   • More invasive than SWL but typically requires only one procedure

3. Percutaneous Nephrolithotripsy (PCNL)

   • Not first-line for 7mm stones (reserved for stones >20mm) 1
   • Would be considered only if SWL and URS fail or are contraindicated 1

Decision Algorithm

1. If patient is asymptomatic or mildly symptomatic:

   • Consider initial trial of MET with alpha blockers for up to 4-6 weeks 2
   • Monitor with follow-up imaging

2. If patient is symptomatic or MET fails:

   • Choose between SWL and URS based on:
     • Patient preference
     • Stone characteristics (density, location)
     • Patient factors (body habitus, bleeding disorders)
     • Facility availability

3. Special considerations:

   • If infection is suspected with obstruction: urgent drainage with stent or nephrostomy tube is required before definitive stone treatment 1, 2
   • For patients on anticoagulation: URS may be preferred over SWL 2

Comparative Outcomes

For a 7mm PUJ stone:

• URS offers higher stone-free rates than SWL (evidence shows URS has a 71% lower risk of residual fragments compared to SWL) 1
• URS typically requires fewer procedures to achieve stone-free status 1
• SWL is less invasive but may require multiple sessions 1
• For stones <1cm, ESWL showed excellent results with 95% stone clearance at 3 months in one study 3

Important Caveats

• If there are signs of infection with obstruction, urgent drainage of the collecting system is mandatory before attempting stone removal 1, 2
• Imaging with low-dose CT is recommended for initial evaluation 2
• Post-treatment follow-up should include imaging to confirm stone clearance
• Stone analysis and metabolic evaluation should be considered to prevent recurrence 2
• Electrohydraulic lithotripsy (EHL) should not be used as first-line for intra-ureteral lithotripsy due to risk of ureteral damage 1