M. Mycyk, E-medicine
Background: Orchitis is an acute inflammatory reaction of
the testis secondary to infection. Most cases are associated with a viral mumps
infection; however, other viruses and bacteria can cause orchitis.
Pathophysiology: Hippocrates first reported the syndrome in
the 5th century BC. While the more common epididymo-orchitis is bacterial in
origin, isolated orchitis usually has a viral etiology.
- In the US: Approximately 20% of prepubertal patients with
mumps develop orchitis. This condition rarely occurs in postpubertal males
with mumps. Bacterial orchitis is even more rare, and it usually is
associated with a concurrent epididymitis.
- Unilateral testicular atrophy occurs in 60% of patients with orchitis.
- Sterility is rarely a consequence of unilateral orchitis.
- Despite some anecdotal reports, there is little evidence supporting an
increased likelihood of developing a testicular tumor after an episode of orchitis.
- In mumps orchitis, 4 out of 5 cases occur in prepubertal males (under 10
- In bacterial orchitis, most cases are associated with epididymitis
(epididymo-orchitis), and they occur in sexually active males over 15 y or
in men over 50 y with benign prostatic hypertrophy (BPH).
- Orchitis is characterized by testicular pain and swelling.
- The course is variable and ranges from mild discomfort to severe pain.
- Associated systemic symptoms:
- Mumps orchitis follows the development of parotitis by 4-7 d.
- A sexual history should be obtained, when appropriate.
- Erythematous scrotal skin
- Enlarged epididymis associated with epididymo-orchitis
- Soft boggy prostate (prostatitis) often associated with
- Most commonly, mumps causes isolated orchitis.
- The onset of scrotal pain and edema is acute.
- As mumps orchitis is responsible for most cases of isolated orchitis,
diagnosis in the ED usually is based on a reported history of a recent
mumps infection or parotitis with a presentation of testicular edema.
- Mumps orchitis presents unilaterally in 70% of cases.
- In 30% of cases, contralateral testicular involvement follows by 1-9 d.
- Other rare viral etiologies include Coxsackie virus, infectious
mononucleosis, varicella, and echovirus.
- Some case reports have described mumps orchitis following immunization
with the MMR (mumps, measles, and rubella) vaccine.
- Bacterial causes, usually spread from an associated epididymitis in
sexually active men or men with BPH, include Neisseria gonorrhoeae, Chlamydia
trachomatis, Escherichia coli, Klebsiella pneumoniae, Pseudomonas
aeruginosa, and Staphylococcus and Streptococcus species.
- Bacterial orchitis rarely occurs without an associated epididymitis.
- Patients are usually sexually active and present with a gradual onset of
pain and edema.
- Unilateral testicular edema occurs in 90% of cases.
- No medications are indicated for the treatment of viral orchitis.
- Bacterial orchitis or epididymo-orchitis requires appropriate antibiotic
coverage for suspected infectious agents. In patients with a bacterial etiology
who are under 35 y and sexually active, antibiotic coverage for sexually
transmitted pathogens (particularly gonorrhea and chlamydia) with
ceftriaxone and either doxycycline or azithromycin is appropriate. Patients
over 35 y with a bacterial etiology require additional coverage for other
gram-negative bacteria with a fluoroquinolone or TMP-SMX. Other appropriate
medications include analgesics or anti-emetics, as needed.