What is the most likely cause and appropriate treatment of epididymo‑orchitis with a reactive hydrocele in a 25‑year‑old man?

Epididymo-orchitis with Reactive Hydrocele in a 25-Year-Old

In a 25-year-old man with epididymo-orchitis and reactive hydrocele, the most likely cause is sexually transmitted infection (primarily Chlamydia trachomatis and Neisseria gonorrhoeae), and treatment should be ceftriaxone 1 g intramuscularly as a single dose plus doxycycline 100 mg orally twice daily for 10-14 days. 1, 2

Most Likely Etiology

• Sexually transmitted pathogens are the predominant cause in this age group, specifically C. trachomatis and N. gonorrhoeae. 1, 2, 3
• The presence of reactive hydrocele indicates an inflammatory response to the infection but does not change the underlying sexually transmitted etiology in a sexually active 25-year-old. 4
• Less common causes in this age group include enteric organisms (particularly in men who practice insertive anal intercourse or have urinary tract abnormalities), Mycoplasma genitalium, and rarely mumps in non-immune individuals. 1, 2, 3

Recommended Treatment Regimen

The 2024 European guideline provides the most current treatment approach:

• Ceftriaxone 1 g intramuscularly single dose PLUS doxycycline 100 mg orally twice daily for 10-14 days 1, 2
• The increased ceftriaxone dose (from previous 500 mg recommendations) addresses strains of gonorrhea with reduced susceptibility. 2
• Dual therapy with azithromycin is no longer recommended unless cefixime is being used as an alternative to ceftriaxone. 1

Alternative Regimens

If gonorrhea is considered unlikely (negative microscopy for gram-negative intracellular diplococci AND no risk factors for gonorrhea):

• Doxycycline 100 mg orally twice daily for 10-14 days as monotherapy 2
• OR Ofloxacin 200-400 mg orally twice daily for 10-14 days 2, 3

If enteric pathogens are suspected (recent instrumentation, insertive anal intercourse, urinary tract abnormalities):

• Ceftriaxone 1 g IM single dose PLUS either ofloxacin or levofloxacin 1, 2
• If enteric organisms are the primary concern: Ofloxacin or levofloxacin as monotherapy 1, 2

Critical Management Points

Immediate Actions

• Start empirical treatment immediately upon clinical diagnosis without waiting for culture results. 2, 3
• Obtain testing for gonorrhea and chlamydia using nucleic acid amplification tests (NAATs). 5
• Add analgesics for symptom control. 6

Monitoring for Complications

• Assess clinical response within 48-72 hours—lack of improvement may indicate abscess formation requiring surgical intervention. 6
• The presence of hydrocele at presentation suggests a more advanced stage of infection but does not automatically require surgical drainage unless there is abscess formation. 6, 7
• Risk of testicular loss is approximately 5%, with abscess formation being a significant predictor (P = 0.035). 8

Important Caveats

• Sexual abstinence for 7 days after single-dose therapy or until completion of multi-day regimens and resolution of symptoms. 5
• Partner notification and treatment is mandatory—all sexual partners from the preceding 60 days should be evaluated and treated. 5, 2
• Test for other STIs including syphilis and HIV. 5
• Repeat testing at 3-6 months is recommended due to high reinfection rates in this population. 5

When to Consider Surgery

• Failure to improve clinically within 48-72 hours of appropriate antibiotic therapy 6
• Documented abscess formation on ultrasound 6, 8
• Progressive testicular enlargement or signs of testicular necrosis 6

Special Considerations

• If M. genitalium is identified on testing, treatment should include moxifloxacin. 2
• Readmission rates for recurrent epididymo-orchitis are approximately 14%, emphasizing the importance of partner treatment and patient education. 8