What is the recommended evaluation and treatment for epididymo‑orchitis, including age‑specific antibiotic choices and follow‑up?

Epididymo-Orchitis: Evaluation and Treatment

Immediate Diagnostic Priority

First, exclude testicular torsion immediately—this is a surgical emergency that presents with sudden-onset severe pain, absent cremasteric reflex, and occurs most commonly in adolescents and young adults; if torsion cannot be ruled out clinically, obtain emergency Doppler ultrasound or surgical consultation within hours, as testicular viability is lost after 6-8 hours. 1, 2

Clinical Presentation to Confirm

• Gradual onset of unilateral posterior scrotal pain developing over hours to days (not sudden) 1, 2
• Palpable epididymal swelling and tenderness, typically starting at the lower pole and progressing upward 1
• Positive Prehn sign: pain relief with scrotal elevation over the symphysis pubis 1
• Intact cremasteric reflex (distinguishes from torsion) 2
• May have scrotal erythema, warmth, reactive hydrocele, or fever in severe cases 1

Age-Based Diagnostic Workup

For Men <35 Years (Sexually Active)

The most common pathogens are Chlamydia trachomatis and Neisseria gonorrhoeae, which cause urethritis-associated epididymitis that frequently presents without significant pyuria. 1, 2

• Obtain urethral Gram stain (≥5 polymorphonuclear leukocytes per oil immersion field confirms urethritis) 1, 2
• Perform nucleic acid amplification testing (NAAT) for N. gonorrhoeae and C. trachomatis on intraurethral swab or first-void urine 1, 2
• If urethral Gram stain is negative, examine first-void uncentrifuged urine for leukocytes 1, 2
• Critical pitfall: Relying solely on urinalysis misses the majority of STI-related cases in younger men, as these infections originate from urethral pathogens rather than urinary tract bacteria 1
• Offer syphilis serology and HIV testing 2

For Men ≥35 Years

Enteric Gram-negative organisms, especially Escherichia coli, predominate and are often associated with bladder outlet obstruction (benign prostatic hyperplasia) or urinary tract abnormalities. 2, 3

• Obtain urine culture and Gram stain for Gram-negative bacteria 2, 3
• Urinalysis examining first-void urine for pyuria 2, 3
• Consider testing for N. gonorrhoeae and C. trachomatis if sexual history suggests STI risk 2

Age-Based Antibiotic Treatment

Men <35 Years (Sexually Active)

Treat with ceftriaxone 250 mg IM single dose PLUS doxycycline 100 mg orally twice daily for 10 days to cover both N. gonorrhoeae and C. trachomatis. 1, 2, 3

• This regimen is recommended by CDC and European Association of Urology as first-line therapy 1, 2
• Do not use ciprofloxacin as first-line in this age group—it lacks adequate anti-chlamydial activity 2
• For cephalosporin or tetracycline allergy: use levofloxacin 500 mg orally once daily for 10 days OR ofloxacin 300 mg orally twice daily for 10 days 2

Men Who Practice Insertive Anal Intercourse

Use ceftriaxone 250 mg IM single dose PLUS levofloxacin 500 mg orally once daily for 10 days (or ofloxacin 300 mg orally twice daily for 10 days) to cover both STI pathogens and enteric organisms. 4

Men ≥35 Years

Treat with levofloxacin 500 mg orally once daily for 10 days OR ofloxacin 300 mg orally twice daily for 10 days as monotherapy to cover enteric Gram-negative organisms. 2, 3

• Fluoroquinolone monotherapy is sufficient because STIs are less common in this age group 2
• Important caveat: Rising fluoroquinolone resistance in E. coli isolates in Europe and the USA necessitates culture-guided therapy adjustments if no improvement occurs 5
• If STI cannot be excluded or testing is unavailable, use the <35 years regimen (ceftriaxone plus doxycycline) 3

Adjunctive Supportive Measures

• Bed rest, scrotal elevation (using rolled towels or supportive underwear), and analgesics until fever and local inflammation subside 2, 3
• Anti-inflammatory medications for pain control 1

Mandatory Follow-Up and Reassessment

Re-evaluate within 48-72 hours (no later than 3 days) to confirm clinical improvement; lack of improvement mandates immediate reassessment of the diagnosis and consideration of alternative conditions. 1, 2, 3

If No Improvement After 3 Days

• Reconsider the diagnosis: testicular torsion, tumor, abscess, testicular infarction, testicular cancer, tuberculosis, or fungal epididymitis 1, 2
• Obtain scrotal Doppler ultrasound to evaluate for abscess, infarction, or tumor 1
• Consider changing antibiotics based on culture and sensitivity results 1
• Surgical consultation may be required for abscess drainage or organ-sparing surgery 6

If Persistent Symptoms After Completing Antibiotics

• Perform comprehensive evaluation for tumor, abscess, chronic epididymitis, or testicular cancer 1, 2
• Do not attribute persistent pain to neuropathic causes without systematically excluding structural pathology 1

Management of Sexual Partners (STI-Related Cases)

• Refer all sexual partners from the preceding 60 days for evaluation and treatment if epididymitis is confirmed or suspected to be STI-related 2
• Patients must abstain from sexual intercourse until both the patient and all partners have completed therapy and are symptom-free 2

Special Populations

• HIV-positive patients should receive the same treatment regimens as HIV-negative patients for uncomplicated epididymitis 2
• Immunosuppressed patients are more likely to have fungal or mycobacterial epididymitis; consider these pathogens if standard therapy fails 2

Indications for Hospitalization or Urgent Surgical Consultation

• Severe pain suggesting torsion, abscess, or infarction 2
• High fever, rigors, nausea, vomiting (suggests abscess or Fournier's gangrene) 1
• Scrotal skin changes: crepitus, necrosis, or rapidly spreading erythema (necrotizing infection) 1
• Uncertain outpatient compliance 2
• No clinical improvement within 48-72 hours of appropriate antibiotic treatment 1, 6

Common Pitfalls to Avoid

• Failure to exclude testicular torsion can result in testicular loss; maintain high suspicion with sudden onset or severe pain 1, 2
• Inadequate diagnostic testing in men <35 years: urethral swab testing is required, not just urinalysis 1
• Using ciprofloxacin in men <35 years: it lacks adequate anti-chlamydial coverage 2
• Failure to reassess within 3 days: delayed recognition of treatment failure or alternative diagnoses increases morbidity 1, 2
• Not treating sexual partners: untreated partners lead to reinfection and ongoing transmission 2