The immune systems response to urinary tract infection may have a bearing on the risk of recurrence – an overactive immune response appears to increase the risk, say researchers at Washington University School of Medicine in St. Louis. Their study is published in the medical journal PLOS Pathogens.

The scientists used a mouse model to demonstrate that severe inflammatory responses to initial urinary tract infection (UTI) may cause damage to the bladder, resulting in longer-lasting infection. They also found that immunodeficient mice – mice with weak immune systems – that did not have these severe inflammatory responses were much less likely to suffer from chronic (long-term, recurring) bladder infection.

They also demonstrated that mice with a history of chronic bladder infection that was subsequently cured with antibiotic treatment develop persistent immune cell infiltrations within the bladder wall, and these mice are highly susceptible to further UTI.