Description

Inflammation (infectious or noninfectious) of epididymis resulting in scrotal pain and swelling, induration of the posterior epididymis, and eventual scrotal wall edema, involvement of the adjacent testicle, and hydrocele formation:

• System(s) affected: Reproductive
• Synonym(s): Epididymo-orchitis
• Classification: Infectious (bacterial, viral, fungal, parasitic) versus sterile (chemical, traumatic, autoimmune, idiopathic, industrial, noninfectious, vasoepididymal reflux syndrome, vasal reflux syndrome); chronic versus acute

Epidemiology

• Predominant age: Usually younger, sexually active men or older men with UTIs; in older men, usually secondary to bladder outlet obstruction
• Predominant sex: Male only

Pediatric Considerations
Occurs in prepubertal boys: Epididymitis is found to be the most common cause of acute scrotum—more common than testicular torsion.

• Common (600,000 cases annually in the US) (1)
• 1 in 1,000 males per year

Prevalence
Common

Risk Factors

• UTI, prostatitis
• Indwelling urethral catheter
• Urethral instrumentation or transurethral surgery
• Urethral or meatal stricture
• Transrectal prostate biopsy
• Prostate brachytherapy (seeds) for prostate cancer
• Anal intercourse
• High-risk sexual activity
• Strenuous physical activity
• Prolonged sedentary periods
• Bladder obstruction (benign prostatic hyperplasia, prostate cancer)
• HIV-immunosuppressed patient
• Severe Behçet disease
• Presence of foreskin (2)
• Constipation
• Sterile epididymitis:
  • Increased intra-abdominal pressure (occupation requiring frequent physical strain):
    • Military recruits, especially who begin physically unprepared
    • Laborers; restaurant kitchen workers
    • Full bladder during intense physical exertion

General Prevention

• Vasectomy or vasoligation during transurethral surgery
• Safer sexual practices
• Mumps vaccination
• Antibiotic prophylaxis for urethral manipulation
• Early treatment of prostatitis/benign prostatic hyperplasia (BPH)
• Avoid vigorous rectal exam with acute prostatitis.
• Sterile epididymitis:
  • Emptying the bladder prior to physical exertion
  • Physically conditioning the body prior to engaging in regular intense physical exertion (3)
  • Treat constipation

Pathophysiology

• Infectious epididymitis:
  • Retrograde passage of urine or urinary bacteria from the prostate or urethra to the epididymis via the ejaculatory ducts and the vas deferens; rarely, hematogenous spread
  • Causative organism is identified in 80% of patients, and varies according to patient age.
• Sterile epididymitis:
  • Can develop as a sequlae of strenuous exercise with a full bladder when urine is pushed through internal urethral sphincter (located at proximal end of prostatic urethra).
  • Reflux of urine through orifice of ejaculatory ducts at verumontanum may occur with history of urethritis/prostatitis, as inflammation may produce rigidity in musculature surrounding orifice to ejaculatory ducts, holding them open.
  • Exposure of epididymis to foreign fluid may produce inflammatory reaction within 24 hours.

Etiology

• <35 years and sexually active:
  • Usually Chlamydia trachomatis or Neisseria gonorrhoeae
  • Look for serous urethral discharge (chlamydia) or purulent discharge (gonorrhea).
  • With anal intercourse, likely Escherichia coli or Haemophilus influenzae
• >35 years:
  • Coliform bacteria usually, but sometimes Staphylococcus aureus or S. epidermidis
  • In elderly men, often with distal urinary tract obstruction, BPH, UTI, or catheterization
  • Tuberculosis, if sterile pyuria and nodularity of vas deferens (hematogenous spread)
  • Sterile urine reflux after transurethral prostatectomy
  • Granulomatous reaction following BCG intravesical therapy for bladder cancer
• Prepubertal boys:
  • Usually coliform bacteria
  • Evaluate for underlying congenital abnormalities, such as vesicoureteral reflux, ectopic ureter, or anorectal malformation (rectourethral fistula).
• Amiodarone may cause noninfectious epididymitis; it resolves with decreasing drug dosage.
• Syphilis, blastomycosis, coccidioidomycosis, and cryptococcosis are rare causes, but brucellosis can be a common cause in endemic areas (4).

Commonly Associated Conditions

• Prostatitis/Urethritis/Orchitis
• Hemospermia
• Constipation
• UTI