Epididymo-orchitis

What is epididymo-orchitis?

Epididymo-orchitis occurs when the testicle (or testis) and epididymis (the coiled tube that lies above and behind the testicle and stores and carries sperm) become infected. Bacteria are usually to blame although the infection may be due to a virus or rarely a parasite such as schistosomiasis, or a fungus.

When infection develops, these two structures become inflamed and swollen, the scrotum feels tender and is red on the side affected. The symptoms usually start after a few hours, and when severe can cause fever and great pain.

Causes and risk factors

The bacteria that cause epididymo-orchitis may get to the testis and epididymis in different ways. In younger men, the bacteria have usually travelled from the penis, having been passed on during sex.

In older men, prostatitis (infection of the prostate gland) or urinary infection is usually to blame. Epididymo-orchitis can also follow any medical procedure involving the urinary tract, such as catheterisation of the bladder or a cystoscopy.

Rarely, the infection arrives from the bloodstream, such as when the micro-organism responsible is tuberculosis (TB) which travels from a source of infection elsewhere in the body. Years ago, before the introduction of immunisation, infection with the mumps virus was a common cause of epididymo-orchitis.

Treatment and recovery

Urine and swab tests are usually performed to confirm the diagnosis and establish the exact cause. If bacteria are identified, the appropriate course of antibiotics is given.

Painkillers and anti-inflammatory drugs can help to relieve the pain and inflammation. Using an ice pack and a scrotal support may help, too and the condition usually settles in just a few days. It’s important, if the infection could have been picked up through sexual contact, to test and treat the partner too.

Although complications are unusual, chronic inflammation may sometimes occur and there may also be reduced fertility, with a lower sperm count from the affected testis especially if the infection was caused by the mumps virus.