Is Urine Sterile? | News | Loyola Medicine
Monday, March 30, 2015

Study debunks common misconception that urine is sterile

Findings will help to explore role of bacteria in health and disease

MAYWOOD, Ill. – Bacteria have been discovered in the bladders of healthy women, discrediting the common belief that normal urine is sterile. This finding and its implications were addressed in an editorial published by researchers from Loyola University Chicago Stritch School of Medicine (SSOM) in the latest issue of European Urology.

“Clinicians previously equated the presence of bacteria in urine to infections. The discovery of bacteria in the urine of healthy females provides an opportunity to advance our understanding of bladder health and disease,” said Alan Wolfe, PhD, lead author and professor in the Department of Microbiology & Immunology, SSOM. “Physicians and researchers must reassess their assumptions surrounding the cause of lower urinary tract disorders and consider new approaches to prevent and treat these debilitating health issues.”

Stritch researchers evaluated urine specimens collected directly from the bladder through an aspiration or a catheter to avoid contamination. These specimens were analyzed using an expanded quantitative urine culture (EQUC) technique that identifies bacteria not detectable by the standard urine culture techniques typically used to diagnose urinary tract syndromes. This study also used 16S rDNA sequencing to classify bacterial DNA.

“While traditional urine cultures have been the gold standard to identify urine disorders in the past, they do not detect most bacteria and have limited utility as a result,” Dr. Wolfe said. “They are not as comprehensive as the testing techniques used in this study.”

Through their analysis, Loyola researchers found that certain bacteria in the female bladder may contribute to symptoms of urinary incontinence. They also revealed that some bacteria are more common in women with urgency urinary incontinence than in healthy women.

“If we can determine that select bacteria cause various lower urinary tract symptoms, we may be able to better identify those women at risk and more effectively treat them,” said Linda Brubaker, MD, MS, co-author, dean and chief diversity officer, SSOM.

Loyola researchers will further explore the role of urinary bacteria in health and disease to learn more about common lower urinary tract disorders such as urinary tract infections, overactive bladder, urinary incontinence and painful bladder syndromes.

About Loyola Medicine and Trinity Health

Loyola Medicine, a member of Trinity Health, is a quaternary care system based in the western suburbs of Chicago that includes Loyola University Medical Center (LUMC), Gottlieb Memorial Hospital, MacNeal Hospital and convenient locations offering primary and specialty care services from 1,877 physicians throughout Cook, Will and DuPage counties. LUMC is a 547-licensed-bed hospital in Maywood that includes the William G. and Mary A. Ryan Center for Heart & Vascular Medicine, the Cardinal Bernardin Cancer Center, a Level 1 trauma center, Illinois's largest burn center, a certified comprehensive stroke center and a children’s hospital. Having delivered compassionate care for over 50 years, Loyola also trains the next generation of caregivers through its teaching affiliation with Loyola University Chicago’s Stritch School of Medicine and Marcella Niehoff School of Nursing. Gottlieb is a 247-licensed-bed community hospital in Melrose Park with 150 physician offices, an adult day care program, the Gottlieb Center for Fitness, the Loyola Center for Metabolic Surgery and Bariatric Care and the Loyola Cancer Care & Research at the Marjorie G. Weinberg Cancer Center at Melrose Park. MacNeal Hospital is a 374-bed teaching hospital in Berwyn with advanced inpatient and outpatient medical, surgical and psychiatric services, advanced diagnostics and treatments. MacNeal has a 12-bed acute rehabilitation unit, a 25-bed inpatient skilled nursing facility, and a 68-bed behavioral health program and community clinics. MacNeal has provided quality, patient-centered care to the near west suburbs since 1919.

Trinity Health is one of the largest multi-institutional Catholic healthcare systems in the nation, serving diverse communities that include more than 30 million people across 22 states. Trinity Health includes 94 hospitals, as well as 109 continuing care locations that include PACE programs, senior living facilities and home care and hospice services. Its continuing care programs provide nearly 2.5 million visits annually. Based in Livonia, Mich., and with annual operating revenues of $18.3 billion and assets of $26.2 billion, the organization returns $1.1 billion to its communities annually in the form of charity care and other community benefit programs. Trinity employs about 133,000 colleagues, including 7,800 employed physicians and clinicians. Committed to those who are poor and underserved in its communities, Trinity is known for its focus on the country's aging population. As a single, unified ministry, the organization is the innovator of Senior Emergency Departments, the largest not-for-profit provider of home health care services—ranked by number of visits—in the nation, as well as the nation’s leading provider of PACE (Program of All Inclusive Care for the Elderly) based on the number of available programs.