Epididymo-orchitis

Question 1

What is it?

Answer 1

Epididymitis is inflammation of the epididymis. Orchitis is inflammation of the testicle. Epididymo-orchitis is usually the result of infection in the epididymis and testicle on one side.

Question 2

What is the epididymis for?

Answer 2

At the back of each testicle is the epididymis. Sperm are released from the testicle, into the head of the epididymis, connected at the top of the testicle. The sperm travel through the head, then body, then tail of the epididymis. Sperm mature and are stored in the epididymis. The epididymis drains into the vas deferens.

Question 3

Causes?

Answer 3

Escherichia coli (E. coli)
Chlamydia trachomatis
Neisseria gonorrhoea
Mumps

Question 4

Presentation

Answer 4

Epididymo-orchitis typically presents with a gradual onset, over minutes to hours, with unilateral:

Testicular pain
Dragging or heavy sensation
Swelling of testicle and epididymis
Tenderness on palpation, particularly over epididymis
Urethral discharge (should make you think of chlamydia or gonorrhoea)
Systemic symptoms such as fever and potentially sepsis

The key differential diagnosis for epididymo-orchitis is testicular torsion. Testicular torsion is a urological emergency that requires rapid treatment to avoid the testicle dying. Both present similarly, with acute onset of pain in one testicle. If there is any doubt, treat it as testicular torsion until proven otherwise.

Question 5

Diagnosis

Answer 5

Investigations are typically guided by the age of the patient
in younger adults assess for sexually transmitted infections (STI)
in older adults with a low-risk sexual history send a mid-stream urine (MSU) for microscopy and culture

Question 6

Management

Answer 6

if an STI is the most likely cause advise urgent referral to a local specialist sexual health clinic CKS
if the organism is unknown BASHH recommend: ceftriaxone 500mg intramuscularly single dose, plus doxycycline 100mg by mouth twice daily for 10-14 days
if enteric organisms are the most likely cause CKS
send an MSU as above
treating empirically with an oral quinolone for 2 weeks (e.g. ofloxacin)
further investigations following treatment may be recommended to exclude any underlying structural abnormalities

Question 7

Complications

Answer 7

Epididymo-orchitis can lead to:

Chronic pain
Chronic epididymitis
Testicular atrophy
Sub-fertility or infertility
Scrotal abscess