AUA 2017: Risk factor assessment for fluoroquinolone resistant E. coli (FRE) in bowel flora is not sufficiently discriminatory: the case for a pre-biopsy rectal swab in all patients

Boston, MA ( Dr. Michael Holmes and colleagues report that there has been a significant rise in infectious complications from transrectal ultrasound guided (TRUS) biopsies due to fluoroquinolone resistant E. coli (FRE) in the bowel flora. The authors sought to discover potential high risk patient factors that may increase the incidence of FRE or sepsis, post biopsy and sought to answer the question: Can we identify a high risk group for FRE and disregard the rest?

In this single unit study, FRE screening has been undertaken since late 2012. Potential risk factors were assessed at the time of biopsy including patients age, number of previous prostate biopsies, international travel within the last 6 months, diarrhea while traveling, antibiotic use in the last 6months, inflammatory bowel disease and diabetes requiring medication. A transrectal swab, screening for FRE, was taken prior to biopsy. Antibiotic prophylaxis was 1 gram p.o. of ciprofloxacin prior to and 500mg after biopsy. Targeted antibiotics were used if a FRE was identified.

Rectal swabs were performed in 1135 of 1216 prostate biopsies. FRE was detected in 95 (8.4%) of which 16 were extended spectrum beta lactamase (ESBL) E.coli. The prevalence of patient risk factors are shown in Table 1. Travel to a developing country within 6 months, ever, and diarrhea while away were associated with FRE carriage (p<0.05). 327 patients had travelled to a developing country of whom 53 carried FRE. A naive classifier based on this would mean screening 30% to detect 50% of FRE carriers. Using leave-one-out the best classifier meant 80% of FRE was detected if 87% of patients were screened.

Dr. Holmes concluded: Travel to a developing country was associated with an increased risk of carrying FRE. However no model could be constructed that would allow screening of a small enough high risk group that was sufficiently useful. Based on this, all patients should be screened for FRE prior to a TRUS prostate biopsy. In a conversation with Dr. Holmes after his presentation, he stated that because of the very low cost, every patient should undergo a rectal swab to determine susceptibility or resistance to Cipro (fluoroquinolone). If resistant, a single dose of ertapenem should be given.


Presentation Authors: Michael Holmes*, Ray Littler, Megan Lyons, Lisa Smit, Glen Devcich, Adam Davies, John leyland, Chris Mansell, Hamilton, New Zealand

Source Of Funding: Waikato Urology Research Limited

Written By: Henry Oat, Patient Coordinator at Desert Medical Imaging, Prostate Cancer Support Group Leader, Patient-Advocate and John Fortin, Retired Healthcare Actuary, Fellow in the Society of Actuaries, and Patient-Advocate. Both John and Henry are prostate cancer survivors.

at the 2017 AUA Annual Meeting - May 12 - 16, 2017 – Boston, Massachusetts, USA