Nonuse of antimicrobial prophylaxis in clean surgeries for adrenal and renal tumors: Results of the risk-based strategy in 1362 consecutive patients

OBJECTIVES To evaluate the incidence of perioperative infections without antimicrobial prophylaxis in patients undergoing clean surgeries for adrenal and renal tumors. METHODS We prospectively enrolled 1362 consecutive patients who underwent minimally invasive adrenalectomy (n = 303), radical nephrectomy (n = 499), and partial nephrectomy (n = 560) using the gasless laparoendoscopic single-port surgery technique between 2005 and 2019. In 1059 patients, antimicrobial prophylaxis was not administered. The remaining 303 patients were considered at high risk for infection and received single-dose antimicrobial prophylaxis. The endpoint was the incidence of perioperative infections within 1 month from the surgery date. Perioperative infections were classified into surgical site infections, urinary tract infections, and remote infections. RESULTS Seventy-four patients whose collecting systems were opened during partial nephrectomy were excluded, and the remaining 1013 patients with nonuse of antimicrobial prophylaxis and 275 patients with single-dose antimicrobial prophylaxis were retrospectively analyzed. The incidence of superficial surgical site infections, deep/organ-space surgical site infections, urinary tract infections, and remote infections was 1.6%, 0.7%, 2.8%, and 1.3%, respectively, in patients with nonuse of antimicrobial prophylaxis and 0.4%, 1.8%, 1.5%, and 1.5%, respectively, in patients with single-dose antimicrobial prophylaxis. All patients who developed perioperative infections were successfully treated. No clinical or surgical variables were significantly associated with the incidence of surgical site infections. One limitation of the present study was its nonrandomized and noncontrolled design. CONCLUSIONS In minimally invasive clean surgeries for adrenal and renal tumors, antimicrobial prophylaxis is not necessary when individual risk of infection is considered low.