The testicles are the pair of organs that sit in the sac below a man's penis. The epididymis is the coiled tube on top of each testicle where sperm are moved from the testicle and stored. Doctors use the term "itis" to mean that an organ is inflamed. For example, orchitis means inflammation of the testicle.
Epididymitis and epididymo-orchitis are usually caused by a bacterial infection. The infection can be caused by:
A urinary catheter (a soft rubber tube that the doctor puts through your penis and into the bladder to let the urine out)
Sometimes, a sexually transmitted disease
Sometimes, you can get epididymitis or epididymo-orchitis without having an infection. Doctors think this may be caused by some urine flowing backward and causing irritation.
The symptoms of epididymitis and epididymo-orchitis are:
Pain from epididymitis usually comes on gradually. Pain from epididymo-orchitis usually comes on more rapidly.
If you have a sexually transmitted disease (STD), you may also have other symptoms, such as a discharge (clear, yellow, or green fluid coming out of your penis).
Epididymitis and epididymo-orchitis usually get better fast with treatment. But sometimes inflammation can happen again or last several weeks (chronic epididymitis).
Doctors suspect epididymitis or epididymo-orchitis based on a physical examination. They'll usually also do:
A urine test to look for infection
Sometimes, ultrasound, to be sure that you don't have a twisted testicle (testicular torsion)