Reduction in Hospital Admission Rates Due to Post-Prostate Biopsy Infections After Augmenting Standard Antibiotic Prophylaxis

Purpose: We evaluated the incidence of infectious complications requiring hospitalization after transrectal ultrasound guided prostate biopsy, comparing an augmented regimen of antibiotic prophylaxis to the standard regimen, and established cost-effectiveness at our center. Materials and Methods: Our standard antibiotic prophylaxis regimen consisted of 3 days of ciprofloxacin or Bactrim (TM) DS in the perioperative period. An increase in hospital admissions related to infection after transrectal ultrasound guided biopsy from January 2010 through December 2010 led us to initiate an augmented regimen of 3 days of ciprofloxacin or Bactrim DS in addition to 1 dose of intramuscular gentamicin before biopsy from January 2011 to December 2011. Urine and blood cultures along with bacterial susceptibilities were obtained at admission and compared between the 2 groups. Cost analysis was done to determine the cost-effectiveness of standard and augmented regimens. Results: The rate of hospitalization due to post-biopsy infections was 3.8% (11 patients among 290 biopsies) in 2010, which decreased to 0.6% (2 patients among 310 biopsies) in 2011 (p <0.001). Of the admitted patients who received standard prophylaxis, 73% had fluoroquinolone resistant Escherichia coli urinary infection and/or bacteremia and only 9% had strains resistant to gentamicin. Multivariate analysis showed that the standard regimen was significantly associated with hospital admission due to post-biopsy infection (HR 2.078 +/- 0.84, p = 0.013). The augmented regimen resulted in a cost savings of $15,700 per 100 patients compared to the standard regimen. Conclusions: The addition of gentamicin to current prophylactic regimens significantly reduced the rate of hospitalization for post-biopsy infectious complications and was shown to be cost-effective.