A bladder infection, also called cystitis, is a bacterial infection within the bladder. Some people call a bladder infection a urinary tract infection (UTI) or cystitis. This refers to a bacterial infection anywhere in the urinary tract, such as the bladder, kidneys, ureters, or the urethra.
While most cases of bladder infection occur suddenly (acute), others may recur over the long-term (chronic). Early treatment is key to preventing the spread of the infection.