Orchitis (or-KIE-tis) is an inflammation of one or both testicles, most commonly associated with the virus that causes mumps. At least one-third of males who contract mumps after puberty develop orchitis.

Other causes of orchitis usually are bacterial, including sexually transmitted infections (STIs), such as gonorrhea or chlamydia. Bacterial orchitis often results from epididymitis, an inflammation of the coiled tube (epididymis) at the back of the testicle that stores and carries sperm. In that case, it's called epididymo-orchitis.

Swelling and pain are the most common signs and symptoms of orchitis.

Oct. 07, 2011

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