Urinary Tract Infections

What Is It?

A urinary tract infection (UTI) is an infection of the urinary system. This type of infection can affect the urethra (urethritis), the kidneys (pyelonephritis) or the bladder (cystitis).

Urine normally contains no bacteria (germs). Urine is a byproduct of the kidneys' filtration system. It forms when the kidneys remove waste products and excess water from the blood. Normally, urine moves through the urinary system without causing any infection. However, bacteria can enter the urinary system from outside the body and cause problems such as infection and inflammation. This is a urinary tract infection.