Rising incidence of acute prostatitis following prostate biopsy: fluoroquinolone resistance and exposure is a significant risk factor.

Objective: To evaluate the frequency and potential risk factors for infection-related complications after transrectal prostate biopsy and to propose adjustments in current antimicrobial prophylaxis recommendations.

Methods: During 2008-2010, 107 patients underwent transrectal ultrasound-guided biopsies of the prostate at our institution. Charts were reviewed for infection-related complications within 30 days of the procedure. Potential risk factors were evaluated, including age, diabetes mellitus, chronic constipation/diverticular disease, prior use of quinolones, enema and prostatitis, on the pathology report. For patients with acute prostatitis, urine and blood samples were assessed for bacteriology and antibiotic susceptibility.

Results: Of our 107 patients, acute prostatitis developed in 10 (9.3%). The most significant risk factor was prior use of a fluoroquinolone antimicrobial, with acute prostatitis developing in 7 (17.1%) of 41 patients who had used a fluoroquinolone compared with 3 (4.5%) of 66 patients who had not (P=.042). Patients who received an enema before the procedure were slightly less likely to develop prostatitis (P=.061). Of 8 positive specimens, the organisms isolated were Escherichia coli in 6, Klebsiella pneumoniae in 1, and Staphylococcus epidermidis in one. Isolated Gram-negative organisms were fluoroquinolone-resistant in 85.7% of samples.

Conclusion: Prior fluoroquinolone intake is a significant risk factor behind a rising incidence of acute prostatitis after transrectal prostate biopsy. Identified pathogens are mostly Gram-negative organisms with a high rate of fluoroquinolone resistance. Alternative prophylaxis regimens for the biopsy procedure should be considered in patients with recent quinolone intake.