Acute cystitis is inflammation of the bladder. It is usually caused by an infection. There are two types are of acute cystitis:

  • Uncomplicated—Premenopausal, nonpregnant women, and in people with no other underlying conditions
  • Complicated—Underlying conditions are present.

The Urinary Tract
The Urinary Tract
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Acute cystitis is most often caused by bacteria. Bacteria enter the urethra and travel into the bladder. The urethra is a tube that allows urine to pass from the bladder to the outside. Bacteria may come from the lower intestines, the rectal area, or skin. Occasionally acute cystitic can be the result of medications or trauma.