Epidemiology
Etiology
- Acute epididymitis: an inflammation of the epididymis, usually as a result of an infection
- Urinary tract infections
- Most common cause among older men and children
- Pathogens: E. coli (most common), Pseudomonas (common), Proteus mirabilis, Klebsiella pneumoniae
- Sexually transmitted infections
- Most common cause among young males (usually < 35 years of age)
- Pathogens: Chlamydia trachomatis (common), Neisseria gonorrhoeae (common)
- Urinary tract infections
Pathophysiology
Clinical features
- Unilateral scrotal pain and swelling, which develops over several days and radiates to the ipsilateral flank
- Tenderness along the posterior testis
- Positive Prehn sign: reduced pain when the affected hemiscrotum is elevated
- Scrotal skin overlying the epididymis may appear red, shiny, and edematous
- Low-grade fever (especially among children)
- Symptoms of lower urinary tract infection (e.g., dysuria, frequency, urgency), including urethritis (urethral discharge)
Tip
- Testicular torsion: negative Prehn sign, negative cremasteric reflex
- Epididymitis: positive Prehn sign, positive cremasteric reflex