Perioperative antibiotic prophylaxis, prostate size and transperineal prostate biopsy

Transperineal prostate biopsy (TPPB) is increasingly used for prostate cancer diagnosis due to low postoperative infection rates. However, the necessity of perioperative antibiotics remains debated. Although infectious complications such as urinary tract infections (UTIs) are uncommon, acute urinary retention (AUR) is a recognized complication. This study compared infection rates between patients undergoing TPPB with versus without perioperative antibiotics and evaluated rates of AUR and its association with prostate size.

We conducted a multi-institutional retrospective review of patients who underwent TPPB from 2012 to 2025. Patients were stratified by receipt of perioperative antibiotics (second- or third-generation cephalosporin) versus no antibiotics. Infection was defined as fever ≥38.3°C with or without UTI symptoms or a positive urine culture (>10⁵ CFU) within 96 h of biopsy. AUR was defined as inability to void within 72 h requiring catheterization. Outcomes were compared based on antibiotic use and development of AUR.

A total of 904 patients were included (771 antibiotics and 133 no antibiotics). Eighteen patients (2.0%) developed infection, with no significant difference based on antibiotic usage (p > 0.05). Patients who developed infection were older than those without infection (71.1 vs. 66.4 years; p < 0.01; confidence intervals [CIs] -8.3, -1.2). AUR occurred in 44 patients (4.9%). Mean prostate volume was significantly greater among patients with AUR compared to those without (77.1 vs. 52.4 ml; p < 0.01; CI -40.6, -8.8). A prostate volume threshold of 79 ml was associated with increased risk of AUR.

Perioperative antibiotics did not reduce infection rates following TPPB. Larger prostate volume is associated with an increased risk of AUR after TPPB.