Transperineal ultrasound-guided prostate biopsy (TPUSPB) is proven to be superior to the traditional transrectal approach due to its lower infection rate1. This reduced infection rate has also been seen in patients who have undergone TPUSPB without antibiotic prophylaxis2. Many institutions have yet to embrace withholding pre-procedure antibiotics in this population. We examined infectious outcomes in patients undergoing TPUSPB at two institutions with different antibiotic practices to determine if differences exist. Four hundred and fifty-two patients from Fox Chase Cancer Center (FCCC) and Vanderbilt University Medical Center (VUMC) were examined. We evaluated outcomes between those who had received antibiotic prophylaxis and those who did not. Outcomes included urinary tract infection (UTI), fever and sepsis within 30 days post-procedure.;;We calculated differences in these outcomes via 2-sided Fisher-exact tests. In our cohort, 217 received no antibiotics and 235 received antibiotics prior to biopsy. We found patient's receiving antibiotics were significantly more likely to have had their biopsy performed at Vanderbilt, Caucasian, Non-Hispanic/Latino and undergone biopsy in a surgery center (Table 1). Among patients without antibiotic prophylaxis, 2 patients (1%) developed a urinary tract infection, versus 1 patient (0.4%) in the antibiotic group (p;= 0.6). Fever (1 (0.4%) vs. 1 (0.4%),;p;= 1.0) and sepsis (1 (0.4%) vs. 1 (0.4%),;p;= 1.0) were equally prevalent between the antibiotic and no antibiotic groups. Four (1.8%) patients without antibiotic exposure developed an infectious complication (including UTI, fever, and sepsis together) versus 3 (1.3%) for those who received antibiotics (p;= 0.7). ;Between these two institutions, we found no difference in infection rates regardless of prophylaxis antibiotic utilization. We did however find significant differences in our two institution antibiotic practices and thus patient populations who were more likely to receive antibiotics due to the demographic differences between these institutions. Omitting antibiotics prior to TPUSPB is safe and further advances the goal of antibiotic stewardship within the field of Urology. [ABSTRACT FROM AUTHOR]