Epididymitis

A 23 year-old university student presents to your office with complaints of pain in his right testicle. The pain has been present for a few days and has been getting worse. He denies and history of trauma, or any urethral discharge, but does confess that he is "quite sexually active", and that he uses condoms "sometimes".

Given this history, which of the following diagnoses do you think is most likely?

1. Torsion of the testicle
2. Acute epididymitis
3. Cancer of the testicle

All three of these conditions must be considered in the differential diagnosis of this case.

There is commonly held misconception that testicular cancers are by and large painless. In fact, testicular pain is a presenting feature of 18% to 46% of patients with germ cell tumors. Acute pain can be associated with torsion of the neoplasm, infarction or bleeding in the tumor, or epididymitis. Signs and symptoms indistinguishable from acute epididymitis have been observed in up to one fourth of patients with testicular neoplasms.

Torsion of the testicle tends to occur more commonly in males under 20 years of age, but can occur in older men. It tends to have a more acute onset of pain and patients tend to seek medical advice soon after the onset of the pain. In this circumstance, acute epididymitis is the most likely diagnosis.

Epididymitis can be defined as inflammation of the epididymis, manifested by a relative acute onset of unilateral testicular pain and swelling, often with tenderness of the epididymis and vas deferens and occasionally with erythema and edema of the overlying skin. The term epididymo-orchitis is used primarily when inflammation occurs in both the epididymis and the testes together.

Epididymitis is primarily an infective condition. In men under 35 years of age, sexually transmitted infection (STI) accounts for 2/3 of epididymitis (47% Chlamydia trachomatis and 20% Neisseria gonorrhoeae). In men over 35 years of age, 75% of cases can be attributed to coliforms or pseudomonas.

The determination of the possible etiologic agent should always be based on the evaluation of the risk of the individual having acquired a sexually transmitted agent.

Accurate data on acute epididymitis are lacking. Therefore, the incidence of this condition in the general population is unknown. In a large retrospective study, 49% of cases were in those 20-29 years old, with 70% of cases in those aged 20-39 years. In adolescents with epididymitis, sexual behaviour should be ascertained, as the cause may be an STI.

Coliforms may be a frequent cause of acute epididymitis in sexually active men in all age groups who practice unprotected insertive anal intercourse.

Patients with acute epididymitis usually present with unilateral testicular pain and tenderness and the onset of pain is generally gradual. In sexually transmitted epididymitis, symptoms of urethritis or a urethral discharge may be present. However, urethritis is often asymptomatic.

Signs of acute epididymitis may include any of the following:

• Tenderness to palpation on the affected side
• Palpable swelling of the epididymitis
• Urethral discharge
• Hydrocele
• Erythema and/or edema of the scrotum on the affected side
• Fever

Evaluation for epididymitis should include the following:

• Urethral swab for Gram stain
• Collection of specimens for identification of N gonorrhoeae and C trachomatis (intraurethral exudate or urine according to available laboratory techniques)
• Microscopy and culture of midstream urine
• If it can be arranged without delay, a Doppler ultrasound may be useful to help
• differentiate epididymitis from testicular torsion
• There is no role for epididymal aspiration in routine clinical practice. It may be useful in recurrent infection that fails to respond to therapy or in patients with suspected abscess formation.

Epididymitis most likely caused by chlamydial or gonococcal infections should be treated with a course of Doxycycline 100 mg PO bid for 10-14 days

PLUS

Ceftriaxone 250 mg IM in a single dose

OR

Ciprofloxacin 500 mg PO in a single dose (unless not recommended due to quinolone resistance). Fluorquilolone resistance is becoming an issue in several parts of the world. It is important to ascertain if the patient has been traveling recently, and it is also helpful to know the fluorquinolone resistance status in your community. This information can be obtained from the Public Health Agency of Canada website.

Epididymitis most likely caused by enteric organisms are best treated with Ofloxacin 200 mg PO bid for 14 days.

Consideration for testing for other STIs, including HIV, should be given according to the patient's sexual history and the presence of risk factors for specific infections. This is also an opportunity to discuss "safe sex" practices. Patients are often more receptive to the concept once they have been infected.

Epididymitis caused by an STI is a reportable disease, and the local public health authority should be notified. In many jurisdictions, positive cultures will automatically go from the lab to the Public Health Department.

When treatment is indicated for the index case, and he is presumed to have sexually acquired epididymitis, all sexual partners from 60 days prior to symptom onset (or the date of diagnosis where asymptomatic) should be clinically evaluated and treated with an appropriate regimen. Public health officials may be helpful in tracking down contacts.

Follow-up should be arranged to evaluate response to treatment. If a recommended regimen has been given and correctly taken, symptoms and signs have disappeared and there is no re-exposure to an untreated sexual partner, repeat diagnostic testing for N gonorrhoeae and C trachomatis is not routinely recommended.

- John Hickey

References:

Abeloff: Clinical Oncology, 3rd ed. (Level 5 evidence)

Canadian Guidelines on Sexually Transmitted Infections 2006 Edition (Level 4 evidence)

You can search for abstracts of the above references by following this link: PubMed