Reducing Post-Prostatic Biopsy Infection Rates

Introduction

Infectious complications resulting from the over 1 million transrectal biopsies performed each year in the United States are on the rise. With the advent of transrectal ultrasound and the Bard biopsy gun, transrectal biopsy, usually for the diagnosis of prostate cancer, has become a standard office procedure. It is relatively painless for the patients and performed under local anesthesia. It is easily learned and has relatively few complications. Those reported include hematuria, rarely with clot retention; hematospermia, urinary retention, urinary tract infection, and occasional but significant sepsis requiring hospitalization. The 30-day hospitalization rate for infectious complications, however, was 6.9% in a recent review of the SEER-Medicare database. The increase in both urinary tract infection and sepsis has been attributed to the increase in fluoroquinolone resistance in Escherichia coli found in stool, urine, and bloodstream isolates.

Targeted Antimicrobial Prophylaxis Using Rectal Swab Cultures in Men Undergoing Transrectal Ultrasound Guided Prostate Biopsy Is Associated With Reduced Incidence of Postoperative Infectious Complications and Cost of Care

Taylor AK, Zembower TR, Nadler RB, et al 
J Urol. 2012;187:1275-1279

Rectal Cultures Before Transrectal Ultrasound-Guided Prostate Biopsy Reduce Post-Prostatic Biopsy Infection Rates

Duplessis CA, Bavaro M, Simons MP, et al
Urology. 2012;79:556-561

Study Summary

A new approach is suggested in the studies by Taylor and colleagues and Duplessis and colleagues. In both papers, patients selected for transrectal prostatic biopsy had rectal culture performed before the biopsy. Antibiotic coverage was targeted according to bacterial sensitivities. Investigators compared the occurrence of infection from these patients with that in patients who received the standard treatment of a Fleet enema and fluoroquinolone. In the 2 studies, the occurrence of fluoroquinolone-resistant E coli was similar: 19.6% in Taylor's study vs 14% in Duplessis'. Remarkably, there were no infectious complications in both studies when targeted antimicrobial therapy was given.

Patients at higher risk include those with a previous biopsy and those who had recent fluoroquinolone therapy for other infections. The obvious drawbacks to the approach are that there is a 1-week delay in obtaining culture results, which requires an additional office visit. In a limited cost analysis, Taylor and colleagues showed that tailored therapy yielded a significant cost savings by avoiding infectious complications, especially the costs of hospitalization associated with sepsis.

Viewpoint

Urologists should consider tailored therapy, especially in men at higher risk for infectious complications. In addition, we need to remember the increasing number of patients with quinolone-resistant E coli urinary tract infections. In a recent review of over 40,000 E coli isolates, 14.2% of the pooled samples were resistant to quinolones, but in the urology samples, 28.6% were resistant. Of note, in the urology samples, 60% were resistant to ampicillin and 35.5% to trimethoprim. Only 5.8% were resistant to nitrofurantoin. A long-standing approach, poorly studied, in patients with resistant E coli has been nitrofurantoin plus urinary acidification.