Alternative Names

Epididymo-orchitis; Testis infection

Definition of Orchitis

Orchitis is swelling (inflammation) of one or both of the testicles.

Causes, incidence, and risk factors

Orchitis may be caused by an infection from many different types of bacteria and viruses.

Signs and tests

A physical examination may show:


Treatments may include:

Expectations (prognosis)

Getting the right diagnosis and treatment for orchitis caused by bacteria can usually preserve the normal testicle function.


Linda J. Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington School of Medicine; and Scott Miller, MD, Urologist in private practice in Atlanta, Georgia. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc. – 9/3/2010

Male reproductive anatomy
Male reproductive system

ADAM Medical Encyclopedia

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