What is the treatment for a ureteropelvic junction (UPJ) stone?

Treatment of Ureteropelvic Junction (UPJ) Stones

Ureteroscopy (URS) or shock wave lithotripsy (SWL) should be offered as first-line therapy for ureteropelvic junction stones, with URS generally preferred due to higher stone-free rates, especially for stones >10mm. 1

Initial Assessment and Management

• Stone characteristics to evaluate:

  • Size (stones >10mm have lower success rates with both URS and SWL)
  • Location (UPJ stones may be more difficult to visualize with ultrasound-based lithotriptors)
  • Density (harder stones may respond less well to SWL)

• Patient factors to consider:

  • Bleeding diatheses or anticoagulation therapy (favors URS) 1
  • Pregnancy status (requires coordination with obstetrician) 1
  • Pediatric patients (both URS and SWL are effective) 1
  • Anatomical abnormalities (may influence approach)

Treatment Algorithm

First-Line Options:

1. Ureteroscopy (URS):

   • Higher stone-free rates (95% for stones <10mm, 78% for stones >10mm) 1
   • Preferred for:
     • Larger stones (>10mm)
     • Patients on anticoagulation therapy
     • When immediate stone clearance is needed
     • Pregnant patients who fail conservative management
   • Technical considerations:
     • Safety guidewire should be used 1
     • Antimicrobial prophylaxis required 1
     • Thulium fiber laser offers higher ablation rates and superior dusting capability 2

2. Shock Wave Lithotripsy (SWL):

   • Good stone-free rates (87% for stones <10mm, 73% for stones >10mm) 1
   • May be preferred for:
     • Small stones (<10mm)
     • Pediatric patients with difficult ureteroscopic access
     • Patients with severe scoliosis or history of ureteral reimplantation 1
   • Limitations:
     • Poor visualization of mid-ureter with ultrasound-based lithotriptors 1
     • Lower success rates for harder stones

Special Populations:

Pediatric Patients:

• For ureteral stones ≤10mm: Initial observation with or without medical expulsive therapy (α-blockers) 1
• For stones unlikely to pass: URS or SWL, with high success rates for both (87-95% for stones <10mm) 1
• Pre-stenting not routinely necessary before URS 1
• Low-dose CT scan recommended prior to percutaneous procedures 1

Pregnant Patients:

• First-line: Observation if symptoms are well-controlled 1
• If intervention needed: URS preferred (holmium laser has minimal tissue penetration) 2
• Coordinate all interventions with obstetrician 1

Patients with Bleeding Disorders:

• URS is first-line therapy for patients with uncorrected bleeding diatheses or on continuous anticoagulation 1

Complications and Management

• If purulent urine is encountered during endoscopic intervention:

  • Abort procedure
  • Establish drainage (stent or nephrostomy)
  • Continue antibiotics
  • Obtain urine culture 1

• Potential complications of URS with laser treatment:

  • UTIs (2-6%)
  • Ureteral injury (3-6%)
  • Ureteral stricture formation (1-5%)
  • Higher complication rates for proximal ureteral stones 2

If Initial Treatment Fails:

• If SWL fails, endoscopic therapy (URS) should be offered next 1
• Re-evaluate stone characteristics that may have contributed to failure
• Success rates for URS as secondary procedure after failed SWL: 62-100% 1

Rare Scenarios:

• Open/laparoscopic/robotic surgery should not be offered as first-line therapy except in rare cases with:

  • Anatomic abnormalities
  • Very large or complex stones
  • Need for concomitant reconstruction (e.g., UPJ obstruction repair) 1

• Percutaneous antegrade approach may be considered for very large (>15mm) impacted stones in the proximal ureter, with stone-free rates of 85-100% 1

By following this evidence-based approach to UPJ stones, clinicians can optimize outcomes while minimizing complications and ensuring appropriate patient-specific care.