Infectious complications following flexible ureteroscopy of the renal collecting system is common and pose significant morbidity to the patients. Various modifications and precautions have been adopted to reduce the incidence of infections. Our study aims to investigate the use of antibiotic irrigation during laser lithotripsy in retrograde intrarenal surgery (RIRS) and assess its reliability in reducing infectious complications.

This prospective study included 150 patients who underwent RIRS between January 2024 and January 2025. The patients were grouped into two as those who received antibiotic irrigation (n:75) and standard irrigation (n:75). In the antibiotic irrigation group, 80 mg of gentamicin was dissolved in normal saline in a 2 L irrigation pouch to obtain a 40 mg/L concentration. In the standard irrigation group, normal saline was used. Preoperative information, including age, sex, body mass index (BMI), ASA score, stone side, stone size, urine culture. The groups were compared with respect to postoperative fever (> 38 °C), systemic inflammatory response syndrome (SIRS), hospital length stay, sepsis, and stone-free rate.A p value of < 0.05 was considered significant.

Demographic criteria across the treatment groups were comparable. Mean age was 53.65 years (SD10.65),Mean stone size was 15.34mm (SD 3.65),mean operative time was 70.10mins(SD31.65).Statistically significant differences were determined between the groups with respect to postoperative fever (p = 0.05), SIRS (p = 0.05), and hospital length of stay (p = 0.05). Sepsis was observed in 5 patients in the standard irrigation group and in one of the antibiotic irrigation group.

Sterilizing the renal collecting system using antibiotic irrigation during RIRS is reliable and efficacious in reducing infectious complications. Larger cohorts are required to draw definitive conclusions and for its application as routine practice.