The inflammation of the epididymis (the tube that carries the sperm from the testes) and testicles is called epididymo-orchitis. It is usually caused by a spread of infection, most commonly Gonorrhoea and Chlamydia in young men.

If it is not treated, it can lead to testicular abscess (pus in the testicle), chronic pain and occasionally infertility (difficulty getting pregnant).

The infections that cause epididymo-orchitis, such as Gonorrhoea and Chlamydia are passed from one person to another during unprotected sex. This includes vaginal, anal and oral sex.

A urine infection can also cause epididymo-orchitis, although this is not sexually transmitted.

Testicular pain and swelling are the most common symptoms of epididymo-orchitis. Some might also notice a discharge (liquid) from the tip of the penis, experience pain when passing urine and rarely, you may have a fever.

Epididymo-orchitis is usually diagnosed by an examination of the testicles at the sexual health clinic. In some circumstances, testicular ultrasound might also help. All patients are also offered a test for Gonorrhoea and Chlamydia.

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Treatment is with antibiotics (tablets taken by mouth) for two weeks. If you are treated for epididymo-orchitis, it is really important that your partner also gets treated before you have sex again to prevent reinfection. Once you have been treated and you take all the tablets, the epididymo-orchitis should not come back unless you have unprotected sex with someone who has an infection.