Do Mixed-Flora Preoperative Urine Cultures Matter?

Journal Article (Journal Article)

OBJECTIVES: To determine whether mixed-flora preoperative urine cultures, as compared with no-growth preoperative urine cultures, are associated with a higher prevalence of postoperative urinary tract infections (UTIs). METHODS: This was a retrospective cohort study. Women who underwent urogynecologic surgery were included if their preoperative clean-catch urine culture result was mixed flora or no growth. Women were excluded if they received postoperative antibiotics for reasons other than treatment of a UTI. Women were divided into two cohorts based on preoperative urine culture results-mixed flora or no growth; the prevalence of postoperative UTI was compared between cohorts. Baseline characteristics were compared using χ2 or Student t tests. A logistic regression analysis then was performed. RESULTS: We included 282 women who were predominantly postmenopausal, white, and overweight. There were many concomitant procedures; 46% underwent a midurethral sling procedure and 68% underwent pelvic organ prolapse surgery. Preoperative urine cultures resulted as mixed flora in 192 (68%) and no growth in 90 (32%) patients. Overall, 14% were treated for a UTI postoperatively. There was no difference in the proportion of patients treated for a postoperative UTI between the two cohorts (25 mixed flora vs 13 no growth, P = 0.77). These results remained when controlling for potentially confounding variables in a logistic regression model (adjusted odds ratio 0.92, 95% confidence interval 0.43-1.96). CONCLUSIONS: In women with mixed-flora compared with no-growth preoperative urine cultures, there were no differences in the prevalence of postoperative UTI. The clinical practice of interpreting mixed-flora cultures as negative is appropriate.

Full Text

Duke Authors

Cited Authors

  • Polin, MR; Kawasaki, A; Amundsen, CL; Weidner, AC; Siddiqui, NY

Published Date

  • June 2017

Published In

Volume / Issue

  • 110 / 6

Start / End Page

  • 426 - 429

PubMed ID

  • 28575903

Electronic International Standard Serial Number (EISSN)

  • 1541-8243

Digital Object Identifier (DOI)

  • 10.14423/SMJ.0000000000000659


  • eng

Conference Location

  • United States