What is epididymitis?

Epididymitis is inflammation (swelling and irritation) of the epididymis, a tube at the back of the testicle that carries sperm. This swelling can cause intense pain in the testicle. It can occur in men of any age, though it happens most often in men between the ages of 14 and 35. There are an estimated 600,000 cases of epididymitis in the United States each year.

What causes epididymitis?

Most cases of epididymitis are caused by an infection, usually by the bacteria Mycoplasma or Chlamydia. These infections often come by way of sexually transmitted diseases. The bacterium E. coli can also cause the condition. Other infections, including with the mumps virus and, rarely, tuberculosis, can also cause epididymitis.

Sometimes epididymitis occurs when urine flows backward into the epididymis. This can happen as a result of heavy lifting. Other causes of epididymitis include:

  • Blockage in the urethra (the tube that carries urine from the body)
  • An enlarged or infected prostate gland (a muscular, walnut-sized gland that surrounds part of the urethra)
  • Use of a catheter (a tube that drains the bladder)
  • Traumatic groin injury

What are the symptoms of epididymitis?

Symptoms of epididymitis include:

  • Pain in the scrotum, sometimes moving to the rest of the groin
  • Swelling and redness in the testicle
  • Blood in the semen
  • Fever and chills
  • Pain when urinating

Last reviewed by a Cleveland Clinic medical professional on 02/07/2018.


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