BACKGROUND: Fluoroquinolones are extensively used as prophylaxis for transrectal ultrasound-guided biopsy of the prostate (TRUBP). Emerging fluoroquinolone resistance and selection of multiresistant organisms warrant new prophylactic strategies. Pivmecillinam and amoxicillin/clavulanic acid have mutual synergistic activity and the combination of these agents has a broad coverage of the majority of microorganisms causing infectious complications after TRUBP and may be a valuable future prophylactic regimen.

PATIENTS AND METHODS: This was a retrospective cohort study of 2624 men that underwent TRUBP at a Danish university hospital. The patients were divided into three groups. Group 1 (n = 1220) received ciprofloxacin before TRUBP, Group 2 (n = 240) received a combination of pivmecillinam and amoxicillin/clavulanic acid before TRUBP and Group 3 (n = 1161) received an extended prophylaxis with pivmecillinam and amoxicillin/clavulanic acid before and for 2 days after TRUBP.

RESULTS: One hundred and ten out of 148 (74.3%) post-TRUBP infections were caused by Escherichia coli, Klebsiella pneumoniae or Enterococcus faecalis. Group 3 with the extended prophylaxis with pivmecillinam and amoxicillin/clavulanic acid had a significantly lower rate of bacteraemia (0.9%) as compared with Group 1 (1.8%) and Group 2 (3.7%). A significant fall in the proportion of ESBL-producing Enterobacteriaceae was observed from the period when ciprofloxacin was used as prophylaxis (8.1%) compared with the subsequent period when pivmecillinam and amoxicillin/clavulanic acid was used (5.9%).

CONCLUSIONS: The combination of pivmecillinam and amoxicillin/clavulanic acid is an attractive prophylaxis for TRUBP from a clinical, bacteriological and ecological point of view as compared with ciprofloxacin.