Gut bacteria adapt to life in bladder

The culprits in recurrent urinary tract infections may be hardy strains of E. coli.

These bacteria have gained the power to hop between the bladder and gut and thrive in the two very different environments a team of scientists reports in the May 8 Science Translational Medicine.

By monitoring levels of microbes in the gut, doctors might be able to catch the bacteria before they travel to the urinary tract, the team suggests.

Scientists knew that gut bacteria that infect the bladder adapt to their new (and usually sterile) environment. Unlike microbes in the gut, bladder-based bacteria use sticky nubs to cling to the organ’s walls and take cover from antibiotics by clumping together and ducking inside individual bladder cells. But researchers thought these lifestyle tweaks would prevent the bacteria from living in the gut.

By analyzing urine and fecal matter from four women with recurrent bouts of urinary tract infections, Jeffrey Gordon of Washington University in St. Louis and colleagues instead found that the same bacteria could survive in both the gut and the bladder. A closer look at one such bug revealed that the strain excelled at finding food in both places and had the equipment to attach to and travel between locations.