#1255

Antibiotic Prophylaxis in Endoscopic Stone Surgery for Patients with Bacteriuria: A Risk-Based Approach

V. Malkhasyan¹, N. Gadzhiev², S. Sukhikh¹, E. Maltsev¹, D. Pushkar³

¹Botkin State Clinical Hospital, Moscow, Russia
²High Medical Technologies Clinic named after N.I. Pirogov, St. Petersburg, Russia
³Russian University of Medicine, Russia

Introduction:

Infectious complications remain a major concern in endoscopic stone surgery, particularly in patients presenting with bacteriuria. Postoperative infections, including febrile urinary tract infections and urosepsis, significantly contribute to patient morbidity, prolong hospital stay, and increase healthcare costs. While prophylactic antibiotic use is well established in cases with sterile urine, there is a lack of consensus regarding optimal timing and duration of antibiotic therapy in patients with asymptomatic or clinically significant bacteriuria. This study aimed to assess the impact of preoperative bacteriuria on postoperative infectious outcomes and to evaluate the effectiveness of a tiered antibiotic prophylaxis protocol based on urine culture and bacterial load.

Material and methods:

A retrospective cohort analysis included 211 patients who underwent endoscopic treatment of upper urinary tract stones between January and July 2023. Patients were stratified based on preoperative urine culture into three groups: sterile urine, low-titer bacteriuria (<10⁵ CFU/mL), and high-titer bacteriuria (≥10⁵ CFU/mL). Antibiotic prophylaxis was administered accordingly: a single preoperative dose for sterile urine, a 3-day course for low-titer bacteriuria, and a 7-day course for high-titer bacteriuria, followed by repeated urine culture prior to surgery. The primary endpoint was the incidence of postoperative hyperthermia, used as a clinical marker of infection.

Results:

Sterile urine cultures were confirmed in 152 patients (72%), while 59 patients (28%) had preoperative bacteriuria. Among these, 31 patients (14.7%) had low-titer and 28 (13.3%) had high-titer bacteriuria. After extended antibiotic therapy, sterility was achieved in 22 of 28 patients (78.6%) with high-titer bacteriuria. Ultimately, 37 patients with residual bacteriuria underwent surgery. Postoperative hyperthermia was observed in 17 cases (8.1%), more frequently among patients with bacteriuria (16.2%) than those with sterile urine (6.3%, p = 0.087). Multivariate logistic regression identified bacteriuria as a significant independent predictor of postoperative hyperthermia (OR = 4.75, 95% CI [1.222; 18.803], p = 0.023). Other parameters, including sex, age, BMI, diabetes, stone volume, and surgical time, were not statistically associated with infection risk (p > 0.05).