Urinary tract infections (UTIs) can range from relatively minor bladder infections to more-serious kidney infections. UTIs are caused when bacteria gets into the urethra and moves to the bladder or kidney. UTI symptoms include painful urination, a frequent need to urinate, abdominal pain near the bladder and blood in the urine. Usually, a bladder infection is treated with antibiotics. A kidney infection requires immediate medical attention and is treated with antibiotics. Women are more prone to UTIs.