What is the recommended treatment for a 4 x 7 mm stone at the left ureteropelvic junction (UPJ) with mild hydronephrosis and a punctate nonobstructing stone in the inferior right renal calyx?

Treatment of Ureteropelvic Junction Stone and Nonobstructing Renal Calyx Stone

For a 4 x 7 mm stone at the left ureteropelvic junction with mild hydronephrosis, medical expulsive therapy with an alpha-blocker such as tamsulosin should be the initial treatment, while the punctate nonobstructing stone in the inferior right renal calyx can be managed conservatively with observation. 1

Management of the Left UPJ Stone (4 x 7 mm)

Initial Management

• First-line approach: Medical expulsive therapy (MET) with alpha-blockers

  • Tamsulosin is most commonly used and works by relaxing ureteral smooth muscle through alpha-1 receptor blockade 1
  • This therapy increases spontaneous stone passage rates by approximately 29% 1
  • Particularly effective for stones >5mm, which applies to this 7mm stone

• Pain management:

  • NSAIDs should be used as first-line analgesics 1
  • Can be combined with acetaminophen for enhanced pain control
  • Opioids should be considered only if NSAIDs are contraindicated

If Medical Management Fails (after 2-4 weeks)

If the stone does not pass with medical therapy, procedural intervention is indicated:

1. Ureteroscopy (URS) with laser lithotripsy:

   • Higher single-procedure stone-free rate compared to SWL 1
   • Particularly effective for UPJ stones
   • Slightly higher risk of ureteral injury (3-6%)

2. Shock Wave Lithotripsy (SWL):

   • 82% stone-free rate for proximal ureteral stones 1
   • Lower complication rate than URS (1-2%)
   • May require multiple sessions
   • Better for stones <10 mm, making it suitable for this 7mm stone

3. Percutaneous approach:

   • Reserved for cases where both URS and SWL fail
   • PCN (percutaneous nephrostomy) may be used to facilitate stone interventions 2
   • Particularly useful for large stone burden or when endourologic approaches are challenging

Management of Right Renal Calyx Punctate Stone

• Conservative management is appropriate for this nonobstructing punctate stone
• No active intervention is needed as small, nonobstructing stones typically don't cause symptoms or kidney damage
• Regular follow-up imaging (ultrasound) to monitor for growth or development of obstruction

Preventive Measures for Both Stones

• Increase fluid intake to >2L/day to help prevent stone growth and recurrence 1
• Consider metabolic evaluation to identify risk factors for stone formation
• Dietary modifications based on stone composition (if known)

Follow-up Recommendations

• Urological follow-up within 1-2 weeks with imaging (KUB X-ray or ultrasound) to assess stone position and progression 1
• Patient education on warning signs requiring immediate medical attention:
  • Fever (potential sign of infection)
  • Uncontrolled pain
  • Nausea/vomiting
  • Signs of worsening obstruction

Important Considerations

• The risk of systemic inflammatory response syndrome following percutaneous procedures correlates with tract number, blood transfusion, stone size, and presence of pyelocaliectasis 2
• UPJ obstruction left untreated may lead to worsening hydronephrosis, chronic infection, or progressive deterioration of renal function 3
• CT is the gold standard for detecting kidney stones with approximately 97% sensitivity 1

This treatment approach prioritizes medical management first for the symptomatic UPJ stone while appropriately observing the asymptomatic nonobstructing calyceal stone, with clear criteria for when to escalate to procedural interventions.