<i>E. coli</i> on Bladder (IMAGE) Washington University School of Medicine Caption White blood cells (small circles) attack infected bladder cells (large circles) in this scanning electron micrograph of a mouse bladder with a bacterial infection. Researchers at Washington University School of Medicine in St. Louis have discovered that an initial urinary tract infection (UTI) triggers changes to immune and other cells in the bladder that can prime the bladder to overreact to bacteria, worsening subsequent UTIs. Credit Valerie O'Brien Usage Restrictions This image is to be used in accordance with the mission, policies and guidelines of Washington University in St. Louis. Visit https://wustl.edu/about/compliance-policies/media-policies/photo-use/ for more information. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.