ObjectivesTo assess whether rectal preparation before transrectal ultrasound (TRUS)-guided prostate biopsy could decrease the rate of infectious complications and to find any possible risk factors affecting the development of complications. MethodsThis retrospective study included 879 cases of TRUS-guided prostate biopsy. All patients received antibiotic prophylaxis with levofloxacin or cefixime orally before biopsy and continually for 7 days after. A total of 456 patients received bisacodyl rectal preparation the night before or on the morning of the biopsy, and 423 did not. Major complications were defined as serious side effects requiring additional treatment. Infectious complications were classified as sepsis, fever (greater than 38°C) without sepsis, and other clinical infection. We evaluated whether rectal preparation before biopsy could decrease infectious complications. Other potential risk factors were also investigated. ResultsMajor complications developed in 47 cases (5.3%), including 1 vasovagal episode, 10 cases of urinary retention, and 46 infectious complications, of which 19 were sepsis and 11 fever without sepsis. Among the potential risk factors, the number of biopsy cores and use of a rectal preparation were statistically significant risk factors influencing the development of infectious complications in multiple logistic regression analysis (P = 0.038 and P = 0.000, respectively). ConclusionsThe number of biopsy cores and prebiopsy rectal preparation use were statistically significant risk factors for infectious complications after prostate biopsy in our study. Thus, we recommend a rectal preparation before prostate biopsy to minimize the risk of infectious complications.