Incidence and Predictors of Infection after Robot-Assisted Radical Prostatectomy: The Role of Peri-Operative Urine Culture

BACKGROUND: Robot-assisted radical prostatectomy (RARP) is a widely used minimally invasive procedure for the treatment of localized prostate cancer. Although pre-operative bacteriuria has been associated with post-operative infections after open prostatectomy, evidence in the RARP era remains limited. The clinical significance of post-operative bacteriuria also remains unclear. PATIENTS AND METHODS: We retrospectively reviewed the records of patients who underwent RARP at our institution between 2019 and 2025. Urinalysis and urine cultures were routinely performed pre-operatively and on post-operative day 4. Infectious complications, including surgical site and urinary tract infections, were assessed within 30 days of operation. We analyzed the association between peri-operative urinary findings and post-operative infections. RESULTS: Among 257 patients, post-operative infections occurred in 11 cases (4.3%). Pre-operative pyuria was significantly more common in the infection group than in the non-infection group (18.2% vs. 3.7%, p = 0.049), whereas pre-operative bacteriuria was not. Post-operative bacteriuria was observed in 45.5% of infected cases compared with 3.3% of non-infected cases (p < 0.001), whereas post-operative pyuria did not differ significantly between the groups. However, severe post-operative pyuria (>50 white blood cells per high-power field) was more frequent in the bacteriuria-positive group than in the bacteriuria-negative group (46.2% vs. 4.1%, p < 0.001). CONCLUSIONS: Pre-operative bacteriuria was not associated with post-operative infections following RARP. In contrast, post-operative bacteriuria was strongly associated with infectious complications. These findings suggest that routine pre-operative urine cultures may be unnecessary in patients without symptoms. However, post-operative bacteriuria may indicate an increased risk of infection, and urine cultures should be considered, particularly in cases with severe pyuria.