The prevalence of prostatitis symptoms could be compared in five studies surveying 10 617 men.

Overall, participants met various criteria for prostatitis with prevalence ranging from 2.2 to 9.7%.

Men reporting a history of prostatitis symptoms had a substantially increased rate of benign prostatic hyperplasia, lower urinary tract symptoms and prostate cancer.

Two studies suggest that about one-third of men reporting prostatitis symptoms had resolution after 1 year.

Patients with previous episodes and more severe symptoms are at higher risk for chronic pelvic pain.

In this condition, a bacterial infection causes swelling and inflammation of the prostate. Doctors can definitively make this diagnosis if bacteria and white blood cells are found in the urine. White blood cells are present when there is inflammation that may or may not be related to an actual infection. True chronic bacterial infection accounts for a small percentage of cases of chronic prostatitis. Sometimes doctors suspect a lingering bacterial infection even though no bacteria are identified.

Doctors make this diagnosis when patients have typical symptoms of chronic prostatitis, but no bacteria are found in a urine sample. The cause of most cases of non-bacterial prostatitis is not well understood. The urine often contains white blood cells. Some patients may have a persistent low-grade infection that cannot be detected in a routine urine sample. However, most patients with non-bacterial prostatitis have no evidence of infection, even when sophisticated tests are done.

This term is used when symptoms of prostatitis are present, but there is no evidence of prostate infection or inflammation. Doctors understand very little about why some people — often young, otherwise healthy men — develop this problem. Theories to explain prostadynia include an abnormal buildup of pressure in the urinary tract, irritation resulting from an autoimmune or chemical process, or pain generated in the nerves and muscles within the pelvis.