Severe acute inflammatory responses to initial UTI lead to bladder damage and allow infection to persist, causing chronic flare-ups, according to a US study.

Researchers said the findings may lead to development of a human vaccine to help prevent recurrent infection.

The team from the Washington University School of Medicine in Missouri assessed the impact of initial UTI on bladder damage in mice. They then repeated the experiment using immuno-deficient mice.

Mice that had a history of chronic bladder infection, despite treatment with antibiotics to clear up the infection, went on to develop persistent immune cell infiltrations within the bladder wall. Researchers found these mice were also susceptible to further UTI.

In addition, mice that lacked the typical acute inflammatory responses were protected from chronic bladder infection.

Writing in PLoS Pathogens, lead author Dr Thomas Hannan said: ‘We found markers in the mice that may one day help us identify patients vulnerable to recurrent infection and refine our treatment strategies.

‘There were infection-fighting elements in the responses of some mice that we might, for example, be able to promote through vaccines for these patients.’

The team will now collaborate with researchers at the University of Washington and Duke University to see if the mouse results can lead them to markers of vulnerability to recurrent infection in humans.

Click here for the full research on PLoS Pathogens 2010 online