What is Epididymitis and Orchitis (epididymo-orchitis)?

Epididymitis and Orchitis is a condition affecting the testis and epididymus (a long structure on the posterior surface of the testes, that stores and matures sperm before if is expelled through the ductus deferens). The condition normally results from ascending infection of the urinary tract, which tracks from the bladder to the male gonads.


The occurrence of these conditions in isolation is rare, with epididymitis and orchitis normally occurring together. In the US, it is estimated that there are 600,000 cases of this condition each year, occurring most commonly in the 19-35 year old age group. The exact incidence in Australia is not known.

Risk Factors

The most common association with this disease is unprotected sexual intercourse and a promiscuous sexual lifestyle. As the bacteria that cause these diseases are primarily sexually-transmitted, patients who maintain such a lifestyle are at increased rick of developing an infection. The condition is also more common among those patients with a history of urethral stricture (narrowing of the urethra) which allows easier access of bacteria to infect the urinary tract. Other predisposing factors include the use of long term urinary catheters, being an uncircumcised male and recent major infections. However, in many cases the cause cannot be identified.


The patient will normally develop symptoms of the condition following a urinary tract infection, unprotected sexual intercouse or urological surgery requiring catheter insertion. The patient will develop unilateral (one-sided) scrotal pain, in associated with testicular swelling, fever, discharge from the penis, pain with urination and pain with sexual intercourse. When adequately treated, the outcome of this disease is good. Without treatment, patients may develop complications such as abscess formation and infertility. However, as the condition is suddenly painful rapid identification and treatment will commonly occur.

How is it Diagnosed

The patient with a suddenly painful testicle must be assessed carefully to exclude certain surgical emergencies such as testicular torsion (twisting of the spermatic cord which can cut off the blood supply and drainage of the testis). Blood tests and urinary samples will be taken to investigate general signs of infection.


With appropriate antibiotic and supportive therapy, this disease will normally resolve without complication. In some severe cases sexual function can be affected and some patients can become sterile. Recurrence is common.


This condition is normally caused by bacterial infection which responds well to antibiotic therapy. The type of antibiotic used will depend on the type of bacteria most common to the area, and the results of urine and blood investigations. An effort should be made to trace the sexual contacts of the patient to contain the infection source. Other support measures include bed rest, pain killers and scrotal elevation to assist the patient through recovery.


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  4. Therapeutic Guidelines: Antibiotic Version 12. Therapeutic Guidelines Limited, 2003.
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