Snapshot A 60-year-old man with a history of benign prostatic hyperplasia presents with one-sided testicular pain and urinary frequency. He also reports pain with urination. Physical exam reveals a swollen right testicle with substantial induration. Urinalysis reveals positive leukocyte esterase and 20 wbc/hpf. He is prescribed antibiotics for epididymitis. Introduction Clinical definition inflammation of epididymis with symptoms of < 6 weeks Epidemiology Incidence 25 per 100,000 persons Demographics men 18-35 years old Risk factors sexual activity bladder outlet obstruction Etiology Pathogens from sexually transmitted infections in men less than 35 years of age Neisseria gonorrhoeae Chlamydia trachomatis Urinary tract pathogens in men greater than 35 years of age Escherichia coli Pseudomonas aeruginosa Pathogenesis consequence of sexually transmitted disease or urinary tract infection retrograde ascent of pathogen bladder outlet obstruction bacteriuria and subsequent retrograde ascent of pathogen Presentation Symptoms testicular pain and often unilateral lower abdominal pain urinary frequency or urgency urinary dysuria Physical exam fever testicular erythema, tenderness, and induration cremasteric reflex intact Prehn's sign decrease in pain with scrotal elevation Imaging Ultrasound indications to rule out testicular torsion findings enlarged and thick epididymis increased blood flow may also find reactive hydrocele Studies Labs urethral swab Gram stain or methylene blue stain showing white blood cells urine positive leukocyte esterase 10 or more wbc/hpf nucleic amplification testing for Chlamydia and Neisseria Differential Testicular torsion absent cremasteric reflex Treatment Medical antibiotics guided by sexual and urologic history drugs ceftriaxone and doxycycline for sexually transmitted diseases fluroquinolones for enteric pathogen ceftriaxone + fluroquinolones for penetrative anal intercourse Complications Sepsis Testicular atrophy Prognosis Resolves with antibiotics