Should antibiotics be started routinely for uncomplicated kidney stones without signs of infection?

Antibiotics for Uncomplicated Kidney Stones

Do not routinely start antibiotics for uncomplicated kidney stones without signs of infection. Antibiotics are only indicated when there is evidence of urinary tract infection, sepsis, or when performing surgical stone intervention.

When Antibiotics Are NOT Indicated

• Uncomplicated, non-infected kidney stones do not require antibiotics 1
• Extracorporeal shock wave lithotripsy (ESWL) does not require antimicrobial prophylaxis in the absence of UTI 1
• Asymptomatic bacteriuria discovered incidentally should not be treated 2
• Surveillance urine testing should be omitted in asymptomatic patients 2

When Antibiotics ARE Indicated

Emergency Situations Requiring Immediate Antibiotics

If sepsis and/or anuria in an obstructed kidney: 1

• Give antibiotics immediately (strong recommendation)
• Perform urgent decompression via percutaneous nephrostomy or ureteral stenting
• Collect urine for culture before and after decompression
• Re-evaluate antibiotic regimen based on antibiogram results
• Delay definitive stone treatment until sepsis resolves

Surgical Intervention Prophylaxis

Antimicrobial prophylaxis is required for: 1

• Ureteroscopic stone removal
• Percutaneous nephrolithotomy (PCNL)
• Open and laparoscopic/robotic stone surgery

Prophylaxis protocol: 1

• Administer within 60 minutes of the procedure
• Base selection on prior urine culture results and local antibiogram
• Single oral or IV dose covering gram-positive and gram-negative uropathogens is recommended
• Re-dose during procedure if case length necessitates

For patients with chronic bacteriuria undergoing ureteroscopy: 1

• A 5-day course of treatment before URS is recommended

Intraoperative Infection Discovery

If purulent urine is encountered during endoscopic intervention: 1

• Abort the stone removal procedure immediately (strong recommendation)
• Establish appropriate drainage (ureteral stent or nephrostomy tube)
• Continue broad-spectrum antibiotic therapy
• Obtain urine culture
• Defer procedure until infection is appropriately treated

Pre-Procedure Evaluation

Before any stone treatment: 1

• Obtain urine microscopy and culture results to exclude or treat UTI (strong recommendation)
• Treat any identified infection before stone removal

Common Clinical Pitfalls

• Do not assume all kidney stones need antibiotics - this promotes antimicrobial resistance and provides no benefit for uncomplicated stones 1
• Do not delay urgent decompression in obstructed, infected systems while waiting for culture results - start empiric broad-spectrum antibiotics immediately 1
• Do not proceed with elective stone surgery if purulent urine is encountered - this can lead to life-threatening sepsis 1
• Do not use prophylactic antibiotics for ESWL in patients without UTI - it is unnecessary 1

Special Considerations for Infection Stones

Struvite/infection stones require: 3, 4

• Complete stone removal as the mainstay of treatment
• Long-term antibiotic therapy is advised after stone removal
• These stones form due to urease-producing bacteria and are inherently infected

Risk Factors for Infectious Complications

Higher risk patients who warrant closer monitoring include: 3

• Immunocompromised patients
• Patients with anatomical anomalies
• Diabetic patients
• History of recurrent urinary tract infections
• Presence of infection stones