Urine Isn't Sterile: Bacteria and Overactive Bladder

Overactive bladder may be associated with bacteria found in urine

(RxWiki News) Researchers appear to have debunked the long-held notion that urine is sterile. And the bacteria in urine may have implications for people with overactive bladder.

These researchers found differing bacterial organisms in urine samples of women with and without OAB. Certain bacteria identified only in those with OAB have been reported to cause urinary tract infections (UTI).

According to the researchers, some of these bacteria may contribute to symptoms of OAB.

"Tell your doctor if you're having sudden, uncontrollable urges to urinate."

It has long been thought that human urine is sterile, absent of any bacterial content. However, this recent study of healthy women and those diagnosed with OAB has suggested otherwise.

The researchers, led by Evann Hilt, a second-year master's student at Loyola University Chicago, recently presented their research revealing that live bacteria were found not only in the bladders of women with OAB, but also in healthy women.

"The presence of certain bacteria in women with overactive bladder appear associated with OAB symptoms," Hilt said in a press statement.

Overactive bladder, often referred to as urinary incontinence, is marked by sudden, uncontrollable and frequent urges to urinate, as well as urine leakage. Previous research on OAB has shown that about 15 percent of women have various symptoms of OAB, and 40 to 50 percent of female patients who seek care for OAB do not respond to traditional treatments. 

“If we determine that certain bacteria cause OAB symptoms, we may be able to better identify those at risk for this condition, and prevent or more effectively treat affected patients,” Hilt said.

For this study, the investigators assessed urine specimens from 90 women using a newer technique called the expanded quantitative urine culture (EQUC) method. EQUC uses modern, DNA-based methods of detection to identify specific bacteria in urine that were not previously known or went undetected in basic urine cultures. 

The results revealed that the bacteria identified in healthy women differed greatly from the bacteria in those diagnosed with OAB. However, according to Hilt, "Further research is needed to determine if these bacterial differences are clinically relevant for the millions of women with OAB and the doctors who treat them."

“Doctors have been trained to believe that urine is germ-free. These findings challenge this notion, so this research opens doors to exciting new possibilities for patient treatment,” said Linda Brubaker, MD, MS, dean of Loyola University Chicago’s Stritch School of Medicine and co-investigator for this research, in a press statement.

The researchers further stated that they are quickly beginning to work on ways to determine how the bacterial content found in patient bladders is helpful or harmful to a human body, in hopes of finding a way to help treat OAB.

This research was presented on May 18 at the annual meeting of the American Society for Microbiology. Research presented at conference should be considered preliminary until published in a peer-reviewed journal.

The research was funded by Astellas Pharma US, Inc., and no conflicts of interest were identified.

Review Date: 
May 19, 2014