Risk factors for acute prostatitis after transrectal biopsy of the prostate

To investigate the incidence, clinical features, pathogenic bacteria, and risk factors associated with acute prostatitis after transrectal prostate biopsy.

We retrospectively reviewed the medical records of 923 transrectal ultrasound-guided needle biopsies of the prostate in 878 patients performed at our institution from June 2004 to May 2009. The indications for biopsy were generally serum prostate-specific antigen (PSA) elevation, abnormal findings on a digital rectal examination, or both. All biopsies were performed with the patient hospitalized except for 10 patients who refused to be hospitalized, and ciprofloxacin was administered as an antibiotic prophylaxis. The incidence, clinical features, pathogenic bacteria, and potential risk factors associated with acute prostatitis after prostate biopsy were evaluated.

Acute prostatitis developed in 18 (2.0%) cases after prostate biopsy. Among them, 9 (1.0%) had bacteremia and 2 (0.2%) showed clinical features of sepsis. Of the total 50 urine or blood specimens sent for culture study, 27 (54.0%) specimens showed positive cultures, including E. coli in 25. Among the 27 culture-positive specimens, 26 (96.3%) were resistant to ciprofloxacin. Among the potential risk factors for acute prostatitis after prostate biopsy, biopsy performed as an outpatient procedure without a cleansing enema (p=0.001) and past history of cerebrovascular accident (p=0.048) were statistically significant.

Fluoroquinolone is effective as an antibiotic prophylaxis for transrectal prostate biopsy in most cases. The incidence of acute prostatitis after transrectal prostate biopsy was 2.0%, and almost all cases were caused by fluoroquinolone-resistant E. coli. A cleansing enema is recommended before transrectal prostate biopsy.