Antiseptic Preparation of the Rectum Prior to Transrectal Prostate Biopsy

1. Purpose This research aims to determine the efficacy and safety of cleaning the rectal mucosa with antiseptic solution (Povidone-iodine) prior to transrectal prostate biopsy.
2. Hypothesis We hypothesize that prophylactic cleaning of the rectal mucosa with antiseptic solution prior to transrectal prostate biopsy will decrease the rate of infectious complications after biopsy. We believe that this can be achieved without any significant complications related to the antiseptic solution.
3. Justification Prostate cancer is the most common cancer in men. Since the diagnosis of prostate cancer requires a transrectal prostate biopsy, this procedure is performed frequently. More than 6000 biopsies are performed in British Columbia each year, and more than 1000 are performed at Vancouver General and UBC Hospitals (combined numbers). In these hospitals, the biopsy is performed by the radiologists using transrectal guidance. Subjects receive antibiotic prophylaxis in the form of ciprofloxacin for three days starting one day before the biopsy. They also instill an enema into the rectum a few hours before the biopsy to empty the rectum. Local anesthetic is injected through the rectal mucosa into the periprostatic space prior to the biopsy. Depending on the size of the prostate, between 8 and 12 cores of tissue are remove from the prostate by repetitive passes of the 18 gauge biopsy needle through the anterior rectal wall. Cleaning the rectum with an antiseptic solution prior to biopsy is not routinely practiced and is not considered a current standard of care.

Despite routine antibiotic prophylaxis, prostate biopsies are associated with a considerable rate of infectious complications. Sepsis after biopsy is described in the literature with an incidence 0.1 to 2.0 %.

Rate of sepsis has been determined in a retrospective but contemporary study of approximately 4500 biopsies at VGH/UBC to occur with a rate of 0.55% (Lange et al., submitted to Journal of Urology). Less severe but more common adverse events include urinary tract infection and fever, which both occur in approximately 10% of men undergoing biopsy.

Cleaning the rectum prior to biopsy offers a potential method to decrease the risk of these infectious complications, and we propose the use of Povidone-iodine for this purpose. Surgical site disinfection is standard in most surgical procedures, and Povidone-iodine is a safe antiseptic utilized routinely for the surgical preparation of the body surface as well as mucosal surfaces, including the vagina, mouth and bowel. Park et al. reported that the mean number of colony-forming units decreased 99.9% after Povidone-iodine cleansing of the rectum. Hay et al. reported similar results with Povidone-Iodine enema administration when combined with metronidazole. Povidone-iodine has been shown to significantly reduce bacterial concentrations in the mucosa of the colon and rectum. Brown et al. reported that a Povidone-iodine enema provided a safe and effective means for preventing bacteremia and bacteruria after transrectal prostate biopsy. Furthermore, severe allergic reaction to Povidone-iodine is rare. 4. Objectives

The objectives of this study are: