Presentation Abstract

Abstract Title: Urine is Not Sterile: The Urinary Microbiota of Overactive Bladder Patients
Author Block: E. E. Hilt1, K. McKinley2, E. R. Mueller3, L. Brubaker3, P. C. Schreckenberger2, A. J. Wolfe1;
1Dept. of Microbiol., Loyola Univ. of Chicago, Maywood, IL, 2Dept. of Pathology, Loyola Univ. of Chicago, Maywood, IL, 3Dept. of Obstetrics/Gynecology & Urology, Loyola Univ. of Chicago, Maywood, IL
Keywords: Urinary microbiota,Overactive bladder
Abstract: Background Contrary to dogma that urine is sterile in the absence of a clinical urinary tract infection (UTI); our research team and others have recently shown the existence of a urinary microbiota in individuals with and without lower urinary tract symptoms. With the knowledge that the lower urinary tract possesses its own unique microbiota, we are exploring potential causes for lower urinary tract syndromes, such as overactive bladder syndrome (OAB), a disorder affecting ~15% of adult women. OAB is characterized by symptoms of urinary urgency, often with frequency and urgency incontinence, nocturia and a negative urine culture. ~40-50% of OAB patients do not respond to conventional anti-muscarinic drug treatment. One possible explanation for this lack of treatment response is a dysbiotic urinary microbiota. Materials Following Loyola institutional review board (IRB) approval for all phases of this project, women undergoing OAB treatment and a comparison group of women undergoing benign gynecologic surgery (controls) gave research consent for the collection and analysis of their urine. Urine samples from OAB (42) and control (42) were examined by both standard and expanded quantitative urine culture (EQUC) techniques. Matrix-assisted laser desorption-ionization time-of-flight (MALDI-TOF) mass spectrometry was used to classify bacterial isolates. Results 60 of the 84 urine specimens (71.4%) grew bacteria. However, 90% of these specimens were deemed “No Growth” by the standard urine culture technique, highlighting its limitations. OAB patients had more diverse urinary microbiota than did control patients: a total of 217 bacterial isolates from 77 different genera were isolated from OAB patients, while 66 bacterial isolates from 33 different genera were isolated from control patients. Organisms isolated solely from OAB patient urines included Actinobaculum schaalii, Aerococcus urinae, Arthrobacter cumminsii, and Oligella urethralis; each has been reported to cause UTI. Conclusions Women with OAB have more diverse urinary microbiota than control patients. This diversity and/or the presence of specific organisms could contribute to OAB symptoms.