Highly effective prophylaxis with ertapenem for transrectal ultrasound-guided prostate biopsy: effects on overall antibiotic use and inpatient hospital exposure.

Summary Background Ertapenem prophylaxis for transrectal ultrasound-guided prostate biopsy (TRUS-PB) has proven highly effective at our institution. A subsequent study showed no selection for carbapenem-resistance, but antimicrobial stewardship (AMS) concerns remained. Aim To assess the effects of this prophylaxis on overall antibiotic consumption and exposure to the hospital environment. Methods All men undergoing TRUS-PB from November 2006-July 2019 were included. Hospital records of men presenting within 30-days of biopsy were searched to determine if post-biopsy infection (PBI) occurred, antibiotic usage, and duration of hospitalisation. Prophylaxis during the pre-ertapenem period (Period 1: 2006-2012) was oral ciprofloxacin for three-days, with oral amoxicillin-clavulanate added in 2009. During the subsequent period (Period 2: 2012-2019) a single intramuscular dose of ertapenem was used. Findings From Periods 1 and 2 1663 and 2357 men, respectively, were included. Median age was 65-years for both groups. Between Periods 1 and 2 PBI incidence decreased from 2.65% to 0.34% (RR 0.13, 95%-CI 0.06-0.27), and PBI-related bacteraemia from 1.14% to 0.04% (RR 0.04, 95% CI-0.01-0.22), with a single bacteraemia during Period 2. PBI-treatment antibiotic consumption decreased from 57.6 to 4.3 Defined Daily Doses (DDDs) per 100-biopsies (difference -53.3, 95%-CI -73.1 to -33.5) and overall consumption (treatment plus prophylaxis) reduced from 580.8 to 104.3 DDDs per 100-biopsies (difference -476.5). PBI-related hospitalised bed-days per 100-biopsies decreased from 9.44 to 0.89 (difference -8.55, 95%-CI -12.31 to -4.79). Conclusion Ertapenem prophylaxis was highly effective and resulted in marked reductions in overall antibiotic consumption and inpatient bed-days. Effective prophylaxis has advantages from an AMS perspective.