In 2014, our translational research team (the Loyola Urinary Education and Research Collaboration (LUEREC) developed an expanded quantitative urine culture (EQUC) protocol that isolates many bacteria that the standard urine culture (SUC) does not detect . In fact, EQUC was able to detect bacteria in more than 90% of urine samples that showed no growth by SUC . Others have obtained similar results [2,5]. IN 2016, We then demonstrated the clinical relevance of this observation by showing that SUC misses 50% of pathogenic, or UTI-causing, bacteria in women with severe UTI symptoms . Not surprisingly, over a third of these women with missed pathogens reported no symptom resolution after treatment based on SUC results . This is likely due to biases within the assay, particularly towards detection of Gram-negative bacteria, most often E. coli, but is also a result of a failure to treat pathogens at colony counts below certain thresholds.
The 2016 Price et al. study  highlights the clear inadequacies surrounding our current, dichotomous concept of UTIs. Although, all aspects of the path forward are not yet clear, it is very clear that antibiotic use should be used cautiously with a specific, targeted therapeutic goal and heightened awareness of the significant collateral effects.
The bladder should be no different than other body sites, where clinicians now recognize the added complexity of the human microbiota and its role on patient wellbeing. How emerging knowledge about the urinary microbiota will ultimately change our definition and clinical care of UTI remains to be seen; we are optimistic that patients can experience improved UTI care with fewer collateral effects.
Price TK1, Hilt EE1, Dune TJ2, Mueller ER3, Wolfe AJ1, Brubaker L4,5
1. Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University Chicago, Maywood, IL, USA.
2. Department of Urology, Center for Female Pelvic Health, Weill Cornell Medicine, New York, NY, USA.
3. Departments of Obstetrics & Gynecology and Urology, Loyola University Medical Center, Maywood, IL, USA.
4. Department of Reproductive Medicine, Division of Female Pelvic Medicine and Reconstructive Surgery, University of California San Diego, San Diego, CA, USA.
5. Division of Female Pelvic Medicine and Reconstructive Surgery, Department of Reproductive Medicine, University of California San Diego, La Jolla, CA, USA
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