title: Rectal swab culture-directed antimicrobial prophylaxis for prostate biopsy and risk of postprocedure infection: a cohort study.
abstract: OBJECTIVE
  To examine the effect of rectal swab culture-directed prophylaxis on the incidence of prostate biopsy-associated infections. Secondary objectives were to determine the rate of fluoroquinolone resistance and extended-spectrum beta-lactamase production in local rectal flora.
  
  
  METHODS
  All men receiving prostate biopsies from February 2013 to February 2014 were included in a retrospective institutional review board-approved study. All received either a preprocedural rectal swab and culture-directed antimicrobial prophylaxis or routine fluoroquinolone antibiotics. Clinical information was collected on infectious complications treated within 30 days of biopsy. Chi-square test, Fisher exact test, and Welch t test were used for statistical analysis. Confounding variables were included in a multivariate logistic regression model.
  
  
  RESULTS
  Of 487 total patients, 314 received preprocedure rectal cultures and 173 did not. Average ages were 62.7 and 64.1 years, respectively (P = .07). There was no difference in mean prostate-specific antigen value (P = .9), Charlson comorbidity score (P = .8), or ethnicity (P = .1). The rectal swab group was more likely to receive supplemental gentamicin (P < .001) and had fewer infectious complications (1.9% vs 2.9%; P = .5). On multivariate analysis, decreased odds of infection was associated with culture-directed antibiotics (odds ratio, 0.70; 95% confidence interval, 0.20-2.50; P = .6). However, the study was only powered to detect a 97% reduction in infections. The incidence of fluoroquinolone resistance and extended-spectrum beta-lactamase production was 12.1% and 0.64%, respectively.
  
  
  CONCLUSIONS
  Our study was underpowered but suggests that there are lower odds of infection with rectal swab-directed antimicrobial prophylaxis. The local incidence of fluoroquinolone resistance is high. A prospective, randomized, controlled trial is warranted to further evaluate this intervention.
authors.affiliation: Department of Urology, University of Washington, Seattle, WA.
authors.forename: Jessica
authors.initials: J
authors.lastname: Dai
authors.affiliation: Warren Alpert Medical School, Division of Urology, Rhode Island Hospital, Providence, RI.
authors.forename: Andrew
authors.initials: A
authors.lastname: Leone
authors.affiliation: Warren Alpert Medical School, Department of Epidemiology and Infection Control, Rhode Island Hospital, Providence, RI.
authors.forename: Leonard
authors.initials: L
authors.lastname: Mermel
authors.affiliation: Warren Alpert Medical School, Division of Urology, Rhode Island Hospital, Providence, RI.
authors.forename: Kathleen
authors.initials: K
authors.lastname: Hwang
authors.affiliation: Warren Alpert Medical School, Division of Urology, Rhode Island Hospital, Providence, RI.
authors.forename: Gyan
authors.initials: G
authors.lastname: Pareek
authors.affiliation: Warren Alpert Medical School, Division of Urology, Rhode Island Hospital, Providence, RI.
authors.forename: Stephen
authors.initials: S
authors.lastname: Schiff
authors.affiliation: Warren Alpert Medical School, Division of Urology, Rhode Island Hospital, Providence, RI.
authors.forename: Dragan
authors.initials: D
authors.lastname: Golijanin
authors.affiliation: Warren Alpert Medical School, Division of Urology, Rhode Island Hospital, Providence, RI. Electronic address: jrenzulli@lifespan.org.
authors.forename: Joseph F
authors.initials: JF
authors.lastname: Renzulli
mesh_terms: D019072:Antibiotic Prophylaxis / Q000379:methods*; D001424:Bacterial Infections / Q000453:epidemiology / Q000517:prevention & control*; D015331:Cohort Studies; D024881:Drug Resistance, Bacterial; D024841:Fluoroquinolones / Q000494:pharmacology; D006090:Gram-Negative Bacteria / Q000187:drug effects / Q000201:enzymology; D006801:Humans; D061705:Image-Guided Biopsy; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology / Q000382:microbiology* / Q000517:prevention & control*; D011467:Prostate / Q000473:pathology*; D012007:Rectum / Q000382:microbiology*; D012189:Retrospective Studies; D018570:Risk Assessment; D001618:beta-Lactamases / Q000096:biosynthesis
chemical_list: D024841:Fluoroquinolones; D001618:beta-Lactamases