Increasing Risk of Infectious Complications After Transrectal Ultrasound–Guided Prostate Biopsies: Time to Reassess Antimicrobial Prophylaxis?

BackgroundAn increasing risk of infectious complications following transrectal ultrasound–guided prostate needle biopsy (PNB) has been observed recently in some centers.ObjectiveTo delineate the risk factors associated with post-PNB bacteremia and/or urinary tract infection (UTI) and determine why this risk has risen over time.Design, setting, and participantsA case–control study in a Canadian tertiary-care center. Cases were all patients who developed bacteremia and/or UTIs after PNB between 2002 and 2011; controls were randomly selected among patients who underwent a PNB without such complications.Outcome measurements and statistical analysisCrude and adjusted odds ratios and their 95% confidence intervals were calculated using logistic regression.Results and limitationsA total of 5798 PNBs were performed during the study period, following which there were 48 cases of urinary sepsis (42% with bacteremia). The incidence increased from 0.52 infections per 100 biopsies in 2002–2009 to 2.15 infections per 100 biopsies in 2010–2011 (p < 0.001). Escherichia coli was the predominant pathogen (75% of cases). Among 42 patients whose post-PNB infection was caused by aerobic or facultative Gram-negative rods, 22 patients (52%) were infected by pathogens resistant to ciprofloxacin. Independent risk factors for post-PNB infection were diabetes, hospitalization during the preceding month, chronic obstructive pulmonary disease, and performance of the biopsy in 2010–2011. In 2010–2011, the minimal inhibitory concentrations for ciprofloxacin increased compared with 2002–2009 (p < 0.03). The major limitation of the study was its retrospective hospital-based nature, which hampered data collection on outpatient antibiotic prescriptions.ConclusionsIn the past 2 yr, ciprofloxacin resistance contributed to the increasing incidence of post-PNB infections in our center. Novel antibacterial prophylaxis approaches need to be evaluated.