Acute epididymitis is an infection of the epididymis.


  • Pain in the scrotum usually develops quite quickly
  • The patient may notice a rapid swelling of the affected hemiscrotum
  • Irritative voiding symptoms and fever may also be present

On exam the hemiscrotum is usually visibly enlarged and the overlying skin reddened. The affected epididymis is quite tender. At first the indurated epididymis may be distinguishable from the testicle but as the inflammatory process continues the epididymis and testicle become one inflammatory mass. A reactive hydrocoele may also develop.

Rectal exam should be done to rule out prostatitis as the source of infection.


  • Urine for C&S
  • Urethral swab
  • ±FBC (±↑WCC)


The diagnosis is often difficult to make because of the similar presentation of testicular torsion. If there is any possibility that torsion exists then a urologist should be consulted. A Doppler ultrasound or testicular flow scan can sometimes be helpful in distinguishing the two conditions but imaging studies should not be done if they will delay surgical treatment.

In a young man a sexual transmitted organism is the most likely cause.

Content by Dr Íomhar O' Sullivan. Last review Dr ÍOS 24/10/22.