Orchitis

Background

Scrotal anatomy

Adult testicle with epididymis (left is posterior): A. Head of epididymis, B. Body of epididymis, C. Tail of epididymis, and D. Vas deferens.

• Inflammation of testis - can be infectious (usually) or non-infectious
• Infectious
  • Viral - most common etiology is mumps (orchitis seen in 20-30% of mumps patients)
    • Epididymis typically not involved
  • Bacterial - typically due to hematogenous spread from epididymis: "epididymo-orchitis"
    • (bacterial infections rarely involve only the testis)
    • bacterial pathogens: N. gonorrhea, C. trachomatis, E. Coli, Klebsiella, P. aeruginosa

Clinical Features

• Testicular tenderness, edema
• May see erythema of overlying scrotum
• Viral orchitis
  • Abrupt onset of scrotal pain/swelling 4-7 days after onset of parotitis
  • Usually unilateral
• Fever, tachycardia
• Inguinal lymphadenopathy
• Patient uncomfortable while seated

Differential Diagnosis

Testicular Diagnoses

• Scrotal cellulitis
• Epididymitis
• Fournier gangrene
• Hematocele
• Hydrocele
  • Hydrocele (peds)
• Indirect inguinal hernia
• Inguinal lymph node (Lymphadenitis)
• Orchitis
• Scrotal abscess
• Spermatocele
• Tinea cruris
• Testicular rupture
• Testicular torsion
• Testicular trauma
• Testicular tumor
• Torsion of testicular appendage
• Varicocele
• Pyocele
• Testicular malignancy
• Scrotal wall hematoma

Evaluation

Doppler ultrasound of epididymitis, seen as a substantial increase in blood flow in the left epididymis (top image), while it is normal in the right (bottom image). The thickness of the epididymis (between yellow crosses) is only slightly increased.

Work-Up

• Testicular ultrasound
• Urinalysis and urine culture
• May also consider GC, Chlamydia cultures

Evaluation

• Combination of clinical features and results of imaging/UA
• Ultrasound may show inflammation, epididymitis, and rules out active torsion
• Urinalysis positive for infection in epididymo-orchitis

Management

• Viral orchitis (mumps): supportive care, cold packs, scrotal elevation, analgesia.
• Bacterial orchitis (epididymo-orchitis):
  • <35yo (assume sexually transmitted):
    • Ceftriaxone 250mg IM x1 AND
    • Doxycycline 100mg PO BID x14 days OR Azithromycin 1gm x1
    • Also treat sexual partner
  • >35yo, NO history of anal intercourse and NOT sexually active:
    • Ofloxacin 300mg PO BID x14 days OR levofloxacin 500mg QD x10 days OR ciprofloxacin 500mg PO BID x14 days
    • IV: piperacillin/tazobactam 3.375g IV q6 or ampicillin/sulbactam 3g IV q6

Disposition

• Generally may be discharged home

See Also

• Testicular Diagnoses