A urinary tract infection (UTI) is an infection in any part of the urinary system, which includes the kidneys, ureters, bladder, and urethra. Most infections involve the lower urinary tract — the bladder and the urethra. UTIs are caused by bacteria entering the urinary tract, leading to symptoms like frequent urination, a strong urge to urinate, pain or burning sensation during urination, cloudy or strong-smelling urine, and pelvic pain.



