Urine Is Not So Sterile After All, Bacteria Found In Urine Of Women With Overactive Bladder

Brett Smith for redOrbit.com – Your Universe Online

Although urine has long-been thought to be sterile, a new study has found that not only can bacteria survive in urine – they are relatively prolific in women with overactive bladder (OAB).

“Doctors have been trained to believe that urine is germ-free,” said Linda Brubaker, dean of Loyola University Chicago’s Stritch School of Medicine (SSOM) and an investigator in the new study, which was presented on Sunday as part of the 2014 General Meeting of the American Society for Microbiology being held in Boston.

“These findings challenge this notion, so this research opens the door to exciting new possibilities for patient treatment,” Brubaker added.

In their presentation, the study team said the presence of bacteria had gone undetected because normal bacteria assays aren’t calibrated properly to analyze urine. Co-investigator Evann Hilt said, quite frankly, that researchers in the past weren’t looking to find latent bacteria in urine.

“For all these years, (analyses looked at) whether or not a person had an infection and with that there was a certain threshold that they used to determine whether or not a person was suffering from an infection,” said Hilt, a graduate student at Loyola. “All the bacteria that we see present are below that threshold.”

To detect these bacteria, the researchers assessed urine specimens of 90 women with and without OAB utilizing a new technique known as expanded quantitative urine culture (EQUC). EQUC was capable of finding bacteria that were not discovered by the typical urine culture means normally used to identify urinary tract syndromes.

The team found that the bacteria in the bladders of healthy women vary considerably from those in women suffering from OAB, indicating that particular bladder bacteria are likely involved in OAB. Around 15 percent of women have OAB and about 40 to 50 percent of impacted women do not benefit from typical treatments. One possible reason behind the insufficient therapy response could be the bacteria within the bladder of these women.

“The presence of certain bacteria in women with overactive bladder may contribute to OAB symptoms,” Hilt said. “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.”

“If we can determine that certain bacteria cause OAB symptoms, we may be able to better identify those at risk for this condition and more effectively treat them,” said co-investigator Alan Wolfe, professor of Microbiology and Immunology at SSOM.

“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,” added Paul Schreckenberger, director of the clinical microbiology laboratory in the Loyola University Health System. “They are not as comprehensive as the EQUC protocol used in this study.”

The study team said they now plan to find out which bacteria in the bladder are beneficial and which are hazardous. They said they will also investigate how these bacteria communicate with each other and interact with their host.