ANTIBIOTIC SELECTION FOR PROSTATE BIOPSY PROPHYLAXIS USING RECTAL SWAB CULTURES REFLECTS LOCAL ANTIBIOGRAM
In the recent manuscript &[Prime]An Update of the AUA White Paper on the More Common Complications of Prostate Biopsy&[Prime], an emphasis was placed on utilization of an antibiogram to determine the community risk of resistant post biopsy infections. However, if an antibiotic augmentation strategy is utilized, there are no current recommendations regarding which antibiotic is preferred within individual communities. Herein, we evaluate the susceptibility profiles of ciprofloxacin resistant E.coli (CRE) identified from rectal swab cultures compared to our local antibiogram to determine if the antibiogram could accurately be utilized in the selection of antibiotic augmentation prior to transrectal prostate biopsy (TRPB).
Pre-TRPB rectal swabs were initiated in January 2016 and data was collected through September 2017 at the South Texas Veterans Health Care System (STVHCS). Culture results and antibiotic resistance profiles were recorded and compared to the proportion of antibiotic resistance in the STVHCS 2016 antibiogram. Fisher Exact test was used for comparisons of proportions in a univariate analysis.
We identified 611 patients who underwent pre-PNB rectal culture, of which 98 were CRE isolates. Our cohort demonstrated an 80% sensitivity to ciprofloxacin as compared to the STVHCS antibiogram sensitivity of 65% (p<0.001). Gentamicin, a commonly used antibiotic augment, demonstrated similar sensitivities between the antibiogram and cohort (90% and 88% respectively). There were no statistically significant differences between the STVHCS antibiogram and the sensitivity profiles of our rectal swab cohort as demonstrated in figure 1, except for Ampicillin/Sulbactam, which was 57% in the antibiogram and 32% in our cohort (p=0.019). Of the CRE identified, 4% (4/98) were considered extended spectrum betalactamase producers (ESBL).</p>
Overall, resistance patterns in CRE isolates from our study population are consistent with the STVHCS antibiogram therefore; a local antibiogram may be utilized in an implementation strategy for targeted antibiotics or augmentation of FQ prophylaxis for PNB.
Funding: Roger L. And Laura D. Zeller Charitable Foundation