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Dear Editor, We recently read with great interest the article entitled “FANS-UAS under local anesthesia for urinary stones with high risk postoperative urosepsis” by Zhang et al in your prestigious journal[1]. In this study, nephrolithiasis accompanied by asymptomatic bacteriuria (ASB) or asymptomatic pyuria (ASP) are considered urinary stones associated with a high risk of postoperative urosepsis (HR-POU). They found that retrograde intrarenal surgery (RIRS) assisted by flexible and navigable suction ureteral access sheath (FANS-UAS) under local anesthesia (LA) is feasible and safe for these HR-POU patients, and preliminary results indicate it may reduce the incidence of postoperative fever. These findings provide an attractive new option for stones with HR-POU. However, several issues merit further discussion. This study is compliant with the TITAN Guidelines 2025 – governing declaration and use of AI[2]. For patients with stone obstruction complicated by pyonephrosis or perinephric abscess, clinical priority is given to drainage methods such as ureteral stent placement or percutaneous nephrostomy[3]. Stone management is deferred to a second-stage procedure once the local infection has improved. However, this study performed first-stage FANS-UAS assisted RIRS on all 28 patients with kidney stones complicated by pyonephrosis without any discussion. Given the potential increased risk of infection following first-stage surgery, preoperative risk assessment and personalized treatment are particularly critical for these patients when opting for a primary surgery treatment plan. Based on the above, we recommend conducting a detailed analysis and discussion of the preoperative assessment and postoperative outcomes for patients with renal calculi complicated by pyonephrosis in this study. In most studies, general anesthesia (GA) is the preferred anesthetic type for RIRS[4]. The advantages of GA in kidney stone surgery include high patient compliance, controlled duration of anesthesia, and control over patient respiratory movements[5]. However, there are few studies evaluating the efficacy of LA during RIRS. This study found no significant differences between the two types of anesthesia in terms of surgical success rate, intraoperative bleeding, and operating time; however, patients in the LA group had a lower risk of postoperative fever. Furthermore, through comparative analysis of postoperative blood immune cells, the authors speculate that the cause may be attributed to the lack of significant impairment in immune function. It is our view that analyzing postoperative immune cells alone cannot fully elucidate the impact of primary surgical treatment under different anesthetic modalities on the immune function of patients with kidney stones. Instead, preoperative immune status should serve as the baseline, and different anesthetic techniques should be evaluated by comparing the degree of change in immune function before and after surgery between the two patient groups. During procedures performed under non-general anesthesia, unstable spontaneous breathing, uncontrollable coughing and sneezing reflexes, or patient movement that cannot be prevented during surgery due to inadequate analgesia may all negatively impact the successful completion of the surgical procedure. According to a study by Sahan et al, mucosal tears and hemorrhage occurred in 4.4% and 2.2% of patients in the regional anesthesia group, respectively[4]. In this study, three cases (0.8%) of patients undergoing LA experienced ureteral perforation. It is conceivable that the surgeon’s comfort level during procedures under local anesthesia would also be significantly reduced. Therefore, the safety and efficacy of RIRS assisted by FANS-UAS under LA require further discussion. In conclusion, this study pioneers an attractive new treatment option for patients with HR-POU kidney stones, but further prospective randomized controlled trials are needed to evaluate its safety and efficacy.