Funding issue

The purpose of the study is to investigate whether the use of gentamicin-based irrigation fluid during ureteroscopy decreases the risk of UTIs and other post-operative infections after surgery.

The primary objective of this study is to determine whether the utilization of gentamicin-based irrigation fluid during ureteroscopy decreases the rate of 30-day post-operative symptomatic urinary tract infections in patients at higher risk of urinary tract infection undergoing stone surgery for urolithiasis.

The secondary objectives of this study are to determine whether the utilization of gentamicin-based irrigation fluid during ureteroscopy affects the 30-day post-operative rates of patient-initiated telephone calls, readmission rates, urosepsis rates based on SIRS criteria, and overall post-operative oral/intravenous antibiotic administration.

In this prospective study, 120 mg of gentamicin prepared in 3 liters of normal saline will be used as irrigation during ureteroscopic surgery for urolithiasis. At this concentration, 40 μg/mL, the MBC would be achieved for pathogenic urogenital bacteria. Due to the concerns of nephrotoxicity and ototoxicity at higher doses of gentamicin, in the unlikely event of complete pyelo-venous backflow, the intravenous circulation of 120 mg of gentamicin would be less than the surgical prophylaxis intravenous dosing for patients weighing more than 60 kg. For the single intravenous dose for surgical prophylaxis, post-operative monitoring of renal function, and gentamicin peak and trough levels are not routinely obtained.

Inclusion Criteria:

• Provision of signed and dated informed consent form
• Stated willingness to comply with all study procedures and availability for the duration of the study
• Diagnosed with urolithiasis (obstructing ureteral stone, large non-obstructing renal stones) warranting surgical intervention in line with American Urological Association guidelines for urolithiasis
• At a higher risk for infectious complications following ureteroscopy based on a history of atleast one of the below:
• 3 more urinary tract infections over 12 month period not on suppressive antibiotic therapy
• Prior infectious complication following ureteroscopy
• Placement of ureteral stent in the setting of obstructing ureteral stone with concern for superimposed urinary tract infection
• Positive pre-operative urine culture treated with culture-appropriate antimicrobial therapy
• Planned for cystoscopy, ureteroscopy with possible laser lithotripsy, and ureteral stent placement
• For females of reproductive potential: use of highly effective contraception for at least 1 month prior to screening and agreement to use such a method during study participation and for an additional 8 weeks after the end of gentamicin administration. Female patients of reproductive potential will have pregnancy screen prior to surgery per standard operating room protocol.
• For males of reproductive potential: use of condoms or other methods to ensure effective contraception with partner

Exclusion Criteria:

• Estimated Glomerular Filtration Rate less than 60 mL/min
• History of sensorineural hearing loss, vertigo, idiopathic dizziness
• Active pregnancy or currently lactating
• Known allergic reactions to components of gentamicin
• Administration of intravenous gentamicin as part of surgical antibiotic prophylaxis