The use of prophylactic ciprofloxacin-containing regimens for prostate biopsies resulted in significantly fewer infective complications than did regimens containing co-amoxiclav and gentamicin, according to an audit of hospital records of 709 patients at one institution.
Researchers in the United Kingdom found that regimens containing ciprofloxacin resulted in an infective complications rate of 2.4%, compared with 12.9% for co-amoxiclav/gentamicin regimens.
The results of this 20-month audit supports the use of ciprofloxacin as part of a prophylactic regimen for transrectal ultrasound-guided prostate biopsy (TRUSP Bx), wrote Mr. Thomas Madden and his coinvestigators in the British Journal of Urology International (BJU International 2011;108:1597-602 [doi:10.1111/j.1464-410X.2011.10160.x]).
Prior to April 2008, patients undergoing TRUSP biopsy were treated with ciprofloxacin 500 mg orally prior to the procedure; followed by 500 mg ciprofloxacin twice daily for 5 days (regimen 1). After April 2008, patients were treated with ciprofloxacin 500 mg orally prior to procedure; followed by 500 mg ciprofloxacin twice daily for 3 days (regimen 2).
Subsequently various recommendations were made to help the hospital to reduce its incidence of Clostridium difficile infection and remain within national guidelines. This included restricting the use of fluoroquinolones and cephalosporins with substitution of co-amoxiclav. The standard antibiotic prophylaxis regimen for all surgeries, including urologic procedures, was changed in July 2008 to 120 mg intravenous gentamicin given 10 minutes preprocedure; followed by 375 mg co-amoxiclav given orally three times daily for 3 days (regimen 3).
In November 2008, the regimen was changed to 120 mg intravenous gentamicin given 10 minutes preprocedure; followed by 625 mg co-amoxiclav given orally three times daily for 3 days (regimen 4). In March 2009, the regimen was changed back to ciprofloxacin 500 mg given orally preprocedure; followed by ciprofloxacin 500 mg given twice daily for 3 days (regimen 5).
"Ciprofloxacin is well documented to achieve excellent prostatic tissue concentration."
"In view of the limited data supporting the change, it was agreed that postoperative infection rates should be monitored to confirm efficacy. This audit looks at the rates of infective complications before and after the change of antibiotic regimen," they wrote.
The investigators identified all patients undergoing TRUSP biopsy from January 2008 through March 2009 from clinic records. Because the electronic patient records at the Cambridge University Hospitals Trust stores all letters from clinics and any admissions, a search starting with the TRUSP Bx clinic letter was able to confirm the antibiotics chosen for prophylaxis. The audit continued for a further 6 months to assess the effect of returning to the use of quinolones as prophylaxis. Patients were divided into five groups based on the antibiotic regimen used.
The two (ciprofloxacin-based) regimens used before the intensive-support team visit were associated with infective complication rates of 0.8% and 2% with 5-day and 3-day courses of ciprofloxacin, respectively. After regimen 3 with gentamicin and co-amoxiclav 375 mg three times daily was introduced, the complication rate rose to 14.4%, and substituting a higher dosage of co-amoxiclav brought only a marginal drop to 11.4%. The incidence of infective complications fell to 3.8%, only after the protocol was changed back to ciprofloxacin.
Overall only 4 patients out of 454 (0.9%) who received ciprofloxacin were admitted for infective complications. In the combined groups given gentamicin/co-amoxiclav, 12 patients out of 255 (4.7%) were admitted with sepsis – which was a highly significant difference.
"Further analysis between the groups shows no significant difference between the 5-day and 3-day regimens of ciprofloxacin in terms of infective complications and no difference between the low-dose and high-dose regimens of co-amoxiclav and gentamicin," wrote Mr. Madden, a clinical fellow in the urology department of Addenbrooke’s Hospital in Cambridge, and his coinvestigators.
Analysis of patients with infective complications showed that only 47% of mid-stream urine specimens and 36% of blood culture samples grew any organisms. Notably, of those that did, 89% grew organisms that were sensitive to co-amoxiclav. "Ciprofloxacin is well documented to achieve excellent prostatic tissue concentrations and it is likely that this is the reason for its effectiveness as a prophylactic agent," the authors wrote.
"However, there should be some caution exercised when using ciprofloxacin as there is evidence that resistant microorganisms exist in the community. The four ciprofloxacin-resistant isolates in this study were evenly distributed between the groups of patients. This would seem to indicate a small but significant prevalence of resistance rather than increasing rates, although the numbers involved are too small in this study to draw firm conclusions."
Mr. Madden had no significant financial relationships to disclose.