What is the recommended treatment for a 1.6cm pelvic lithiasis (kidney stone)?

Treatment of 1.6cm Pelvic Lithiasis (Kidney Stone)

For a 1.6cm kidney stone in the renal pelvis, flexible ureteroscopy (fURS) or percutaneous nephrolithotomy (PCNL) should be offered as first-line treatment options, with PCNL providing higher stone-free rates. 1

Diagnostic Evaluation

• Non-contrast CT is the standard imaging modality for accurate assessment of stone location, burden, density, and surrounding anatomy 1
• Low-dose CT maintains high diagnostic accuracy (93.1% sensitivity, 96.6% specificity) while reducing radiation exposure 1
• Biochemical evaluation including urinalysis, creatinine, uric acid, ionized calcium, sodium, potassium, blood cell count, and C-reactive protein is recommended 1

Treatment Options Based on Stone Size and Location

For 1.6cm Renal Pelvic Stone:

• First-line options:

  • Flexible ureteroscopy (fURS) - recommended for stones between 10-20mm in the renal pelvis 1
  • Percutaneous nephrolithotomy (PCNL) - also recommended for stones between 10-20mm 1

• Second-line option:

  • Extracorporeal shock wave lithotripsy (ESWL) - less effective for stones >15mm 1

Procedural Considerations

For Flexible Ureteroscopy (fURS):

• Laser lithotripsy is the preferred method for stone fragmentation 1
• Complete stone removal should be the goal rather than "dust and go" approach 1
• Routine stenting before fURS is not required but may improve outcomes for renal stones 1
• Post-procedure stenting is not necessary after uncomplicated procedures 1

For Percutaneous Nephrolithotomy (PCNL):

• Higher stone-free rates compared to fURS for stones approaching 2cm 2
• Perioperative antibiotic prophylaxis is strongly recommended 1, 2
• Preoperative urine culture should be obtained to exclude or treat urinary tract infection 2

For Extracorporeal Shock Wave Lithotripsy (ESWL):

• Less effective for stones >15mm 1
• Contraindicated in pregnancy, bleeding disorders, uncontrolled UTI, severe obesity, skeletal malformations, or arterial aneurysm near the stone 1
• Decreasing frequency (from 120 to 60-90/min) improves stone-free rates and reduces tissue damage 1

Special Considerations

• If infection is suspected with an obstructing stone, urgent decompression via percutaneous nephrostomy or ureteral stenting is strongly recommended before definitive treatment 1, 2
• Medical expulsive therapy (alpha-blockers) after lithotripsy aids stone passage and reduces colic 1
• For patients on antithrombotic therapy, fURS is classified as a procedure with low risk of bleeding, while ESWL and PCNL carry higher bleeding risks 1

Post-Procedure Management

• Stone analysis should be performed to guide prevention strategies 1, 2
• Medical management should be implemented after stone removal to prevent recurrence 2
• Increased fluid intake to achieve at least 2L of urine output per day is recommended 2
• Regular follow-up imaging is necessary to ensure complete stone clearance 2

Potential Complications

• PCNL carries risks including bleeding, infection, and injury to surrounding structures 2
• ESWL complications include steinstrasse (4%), macroscopic hematuria (17.2%), pain (12.1%), and rarely sepsis (0.15%) 1
• Stent discomfort can be managed with alpha-blockers 1, 2

In conclusion, for a 1.6cm pelvic kidney stone, both fURS and PCNL are appropriate first-line treatments, with PCNL offering higher stone-free rates but potentially more complications. The choice between these options should consider stone characteristics, patient factors, and surgical expertise.