Inflammation of the urinary bladder (seeurinary system). Infections with bacteria, viruses, fungi, or parasites usually spread from nearby sites. Symptoms include burning pain during and right after urination, unusually urgent or frequent urination, and lower back pain. Women, with a shorter urethra than men, are more susceptible to cystitis, most cases resulting from E. coli bacteria from the rectum. Acute cystitis, usually bacterial, causes swelling, bleeding, small ulcers and cysts, and sometimes abscesses. Recurrent or persistent infection can lead to chronic cystitis, with bladder-wall thickening. Diagnosis is made by finding bacteria or other organisms in the (normally sterile) urine. It is treated with drugs or surgery.