A prospective randomized comparative study of targeted versus empirical prophylactic antibiotics in the prevention of infective complications following transrectal ultrasound-guided prostate biopsy.

Background: It is established that antibiotic prophylaxis prevents infection following transrectal ultrasound-guided prostate biopsy. This study compares the infective complications in transrectal prostate biopsy (TRPB) in empirical versus targeted prophylactic antibiotics. Patients and Methods: Urine and rectal swabs were obtained prior to TRPB. They were randomized into targeted antibiotic (TA) and empirical antibiotic (EA) groups. TA had prophylactic antibiotics according to rectal swab culture, whereas EA had the standard parenteral ciprofloxacin. They were followed up weekly for 4 weeks. Chi-square or Fisher's exact tests were used to compare categorical variables, Student's "t"-test was used to compare means of numerical variables, and P < 0.05 was considered statistically significant. Results: One hundred patients were studied, fifty in each group. The mean age was 66 years, with men aged 60-69 years accounting for 50% of the study population. Providencia stuartii, Escherichia coli, and Citrobacter freundii were the most predominant bacteria identified in the prebiopsy rectal swab culture, with resistance to ciprofloxacin (57%) being much more common than that to levofloxacin (21%). Postbiopsy infection occurred in one (2%) patient in the TA group and five (10%) patients in the EA group. Difference in the infection rate between the two groups was statistically significant (P = 0.042). Three of the patients with postbiopsy infection in the EA group had urosepsis and required hospitalization. Fluoroquinolone-resistant bacteria were responsible for infection in all the six patients. TA reduced the risk of postbiopsy infection by 5.6 folds. Conclusion: TA was associated with a decreased risk of infection in TRPB.