Urinary Tract Infection Urinary tract infections, often called UTIs, are common - especially in women - but they should not be ignored. A UTI happens when bacteria enter the urinary tract and cause infection. The infection most often involves the bladder, but it can sometimes spread to the kidneys if not treated appropriately. Common UTI Symptoms A UTI may cause: Burning, pain, or discomfort when urinating Urinating more often than usual Feeling an urgent need to urinate Lowe