Stone Management

Treatment Considerations

The American Urological Association recommends the use of the holmium laser, ultrasonic and pneumatic devices during URS to fragment cystine stones, as they can readily break down these stones 1
Percutaneous antegrade removal may be considered for very large (>15mm) impacted stones in the proximal ureter, according to the American Urological Association 1
Both SWL and URS are effective in pediatric patients, but children appear to pass stone fragments after SWL more readily than adults, as reported by the American Urological Association 1
For stones ≤20 mm (non-lower pole), ureteroscopy (URS) or Shock Wave Lithotripsy (SWL) are recommended, with URS preferred due to higher single-procedure stone-free rates and lower likelihood of repeat procedures, according to the American Urological Association 2
For stones >20 mm, Percutaneous Nephrolithotomy (PCNL) is recommended as first-line therapy, and SWL should NOT be offered as first-line therapy, as per the American Urological Association 2
For stones larger than 10 mm in the lower pole, Ureteroscopy (URS) is preferred over Shockwave Lithotripsy (SWL) due to higher stone-free rates 2
Cystine stones respond poorly to SWL, and URS or PCNL are recommended, according to the American Urological Association 3

The European Association of Urology recommends completing a 7-14 day course of antibiotics based on culture results for urinary tract infections (UTIs) 4
For complicated UTIs with systemic symptoms, the European Association of Urology recommends using Amoxicillin plus an aminoglycoside, OR a second-generation cephalosporin plus an aminoglycoside, OR an intravenous third-generation cephalosporin 4
Fluoroquinolones, such as levofloxacin, should be used only if local resistance is <10% and the patient has not used fluoroquinolones in the last 6 months 4
Broad-spectrum antibiotic coverage is needed until culture results are available for patients presenting with systemic symptoms, as recommended by the European Association of Urology 4

Urgent drainage of the collecting system with a ureteral stent or percutaneous nephrostomy tube is mandatory in patients with obstructing kidney stones and suspected infection to prevent urosepsis and significant morbidity or mortality, as per the American Urological Association 2
Immediate drainage of the collecting system is recommended, with delay of definitive stone treatment until infection is controlled, according to the American Urological Association 2
Alpha-blockers and anti-muscarinic therapy may be offered to reduce stent discomfort, as per the American Urological Association 2

CT urogram with 10-minute delayed images is the gold standard for evaluating suspected ureteral obstruction, with a sensitivity of 97%, as recommended by the American College of Radiology 5

The following imaging modalities have varying sensitivities and specificities:

Modality	Sensitivity	Specificity	Best For
CT	97%	High	Detecting kidney stones
Ultrasound	75% (overall), 38% (ureteral stones)	Moderate	Monitoring stone position and size
KUB radiography	Moderate	Low	Monitoring stone position and size

Increase fluid intake to achieve urine volume of at least 2.5 liters daily to help prevent recurrence, as suggested by the AUA 6, 1, 7
Limit sodium intake and consume 1,000-1,200 mg of dietary calcium per day for calcium stone formers to reduce recurrence risk 6
Evaluation for predisposing factors should include checking for congenital urological abnormalities, neurogenic bladder, metabolic disorders, and recurrent urinary tract infections, as recommended by the AUA 8
Metabolic evaluation should be considered to prevent recurrence, as recommended by the AUA 6, 7, 1
Consider medical expulsive therapy (alpha blockers) to facilitate stone passage, especially for stones ≤10 mm, as recommended by the AUA 1
Follow-up with imaging (KUB X-ray or ultrasound) to assess stone position is recommended within 1-2 weeks of treatment, as recommended by the AUA 1, 9, 10

Normal saline irrigation must be used for PCNL and URS procedures to avoid electrolyte abnormalities, as recommended by the AUA 2
Flexible nephroscopy should be a routine part of standard PCNL, according to the AUA 2
Tubeless PCNL is an option for uncomplicated cases, as per AUA guidelines 2
Retrograde ureteral stenting is recommended as a first-line approach to relieve obstruction, as suggested by the American College of Radiology 11
Percutaneous nephrostomy (PCN) is suggested as an alternative approach if retrograde stenting fails or is contraindicated, as recommended by the American College of Radiology 11

The following treatment options have varying stone-free rates and complication risks:

Treatment	Stone-Free Rate	Complications	Best For
URS	Higher (single procedure)	Slightly higher rates of ureteral injury (3-6%)	Most stone locations, especially >10 mm
SWL	Lower (may need multiple sessions)	Lower rates of ureteral injury (1-2%)	Proximal stones <10 mm