II. Definitions
- Epididymitis
- Inflammation of the epididymis, typically due to Bacterial Infection (esp. Gonorrhea, Chlamydia)
- Much more common than Orchitis
-
Orchitis
- Inflammation of the Testicle, typically due to Viral Infection (esp. mumps)
- Epididymo-orchitis
- Inflammation of both the epididymis and the Testicle
III. Epidemiology
- Incidence (U.S.): 1 per 1000
- Boys (up to age 13 years old)
- Prepubertal Epididymitis is much less common than Testicular Torsion in this age group
- Accounts for one-third of Scrotal Pain in prepubertal boys
- Mean age of onset 11 years old
- Five year recurrence rate: 25%
- Men: Acute Epididymitis
- Ages 20-39 years old (43% of cases, especially STD for those under age 35 years old)
- Ages 40-59 years old (29%)
- Men: Chronic Epididymitis
- Mean age: 49 years old
IV. Pathophysiology
- Ascending infection via vas deferens from prostatic Urethra
V. Causes: Cohort
- Age <14 years
- Idiopathic
- Anatomic abnormalities (e.g. urine reflux into the ejaculatory ducts)
- Bacterial Urinary Tract Infection (typically Escherichia coli)
- Post-infectious (Mycoplasma pneumoniae, Adenovirus, Enterovirus) or active Viral Infections
- Henoch-Schonlein Purpura (bilateral vasculitic Epididymitis, ages 2 to 11 years old)
- Age 14 to 35 years old (sexually active)
- Neisseria gonorrhoeae
- Chlamydia trachomatis
- Enterobacteriaciae (uncommon)
- Age >35 years
- Bacterial Urinary Tract Infection (typically Escherichia coli)
- Bladder outlet obstruction (BPH related)
- Men who practice insertive anal intercourse
- Enteric Bacteria
-
Human Immunodeficiency Virus
- Cytomegalovirus
- Salmonella
- Toxoplasmosis
- Ureaplasma Urealyticum
- Corynebacterium
- Mycoplasma
- Mycobacterium tuberculosis
- See Fungal organisms below
VI. Causes: Infectious
- See Orchitis
- Common - Sexually Transmitted Infection (esp. ages 14 to 35 years)
- Common - Non-Sexually Transmitted (esp. over age 35 years)
- Uncommon
- Ureaplasma Urealyticum
- Proteus mirabilis
- KlebsiellaPneumoniae
- Pseudomonas aeruginosa
- Rare
- Mycobacterium tuberculosis
- Cytomegalovirus (HIV Infection)
- Brucella
- Burkholderia pseudomallei (Pseudomonas pseudomallei)
- Tropical and subtropical asia (Thailand, Northern Australia)
- Fungal organisms (HIV Infection or other immunosuppressed condition)
- Histoplasmosis
- Coccidiodes
VII. Causes: Inflammatory conditions
- Post-infectious inflammation (more common in prepubescent boys with 0.1% Incidence)
- Mycoplasma pneumoniae
- Enterovirus infection
- Adenovirus infection
- Mumps Virus (see Orchitis)
- Other inflammatory Epididymitis causes
- Medication induced (e.g. Amiodarone, BCG vaccine)
- Immunoglobulin A Vasculitis (Henoch-Schonlein Purpura)
- Sarcoidosis
- Behcet Syndrome
VIII. Risk Factors
-
General risks
- Sexual activity (esp. history of Sexually Transmitted Infection)
- Strenuous Exercise
- Bicycle or motorcycle riding
- Prolonged sitting
- Trauma
- Additional risks in prepubescent males and those over age 35 years
- Urinary tract procedures
- Prostatic obstruction (older men) or other Bladder outlet obstruction
- Meatal stenosis
- Posterior Urethral valves (boys)
- Amiodarone
IX. Differential Diagnosis
-
Testicular Torsion
- Critical to differentiate (uncommon outside ages 8 to 35 years and newborns)
-
Torsion of Testicular Appendage
- Uncommon outside ages 7 to 20 years old
- Blue dot sign (blue discoloration of Scrotum over the torsed appendage)
-
Orchitis
- Concurrent with Epididymitis in 58% of cases
-
Inguinal Hernia
- Swollen, tender Scrotum
- Testicular Cancer
X. Symptoms
- Gradual onset of unilateral Scrotal Pain
- Pain localizes to posterior Testicle
- Pain may radiate to opposite Testicle or into lower Abdomen
- Contrast with Testicular Torsion where pain is sudden and unilateral
- Testicular Torsion pain may recur if torsion is intermittent (rare in Epididymitis)
- Orchitis may also present with sudden unilateral Testicular Pain and often comorbid with Epididymitis
- Symptoms of Urinary Tract Infection may be present (rare in Testicular Torsion)
- Fever
- Urethral discharge
- Urinary Frequency
- Urinary urgency
- Dysuria
- Hematuria
XI. Signs
- Epididymis inflammation
- Tenderness to palpation at the epididymis, superior and posterolateral to Testicle
- Epididymis is enlarged and indurated
- Adjacent scrotal and testicular inflammation may occur with Testicular Torsion or infection
- Orchitis and Testicular Torsion both cause Testicular Swelling, scrotal erythema, reactive Hydrocele
-
Cremasteric Reflex present in both Orchitis and Epididymitis
- Stroking inner thigh, retracts Testicle
- Absent in Testicular Torsion
-
Prehn's Sign Positive
- Elevation of Scrotum relieves pain of Epididymitis
- In contrast, with Testicular Torsion, does not offer relief, and may exacerbate pain
- Unreliable as a single test in distinguishing Epididymitis from Testicular Torsion
-
Testes assume normal position in Epididymitis (and Orchitis)
- Contrast with Testicular Torsion where the Testicle is high-riding with transverse orientation
XII. Labs
-
Urinalysis and Urine Culture (first void urine samples are preferred)
- Often normal despite Epididymitis
- Pyuria (Urethritis) may be present in Epididymitis and absent in Testicular Torsion
- Leukocyte esterase positive
- Urine White Blood Cells present on microscopy (>10 cells per hpf)
- Urethral secretions (Gram Stain, gentian violet or methylene blue) with >2 wbc/hpf
-
C-Reactive Protein (CRP)
- Increased in Epididymitis and Orchitis >24 mg/L in most cases
- C-RP is typically normal in Testicular Torsion
- C-RP processing time may preclude use to triage Ultrasound
- Test Sensitivity (96%)
- Test Specificity (92%)
- Doehn (2001) Eur Urol 39:215-21 [PubMed]
- Increased in Epididymitis and Orchitis >24 mg/L in most cases
- Sexually Transmitted Disease testing (PCR Urethral swab or first-void urine)
XIII. Imaging: Color doppler Scrotal Ultrasound
- Indications
- Consider in all cases where Testicular Torsion cannot otherwise be excluded
- Differentiates Epididymitis and Orchitis (increased Blood Flow) from Testicular Torsion (absent Blood Flow)
- Epididymitis
- Epididymis with increased Blood Flow, hyperemia and swelling
-
Testicular Torsion
- Decreased or absent testicular Blood Flow
- Torsion of appendix Testis
- Appendage spherical and >5mm
- Increased periappendiceal Blood Flow
-
Testicular Cancer
- Distinct Testicular Mass
XIV. Management: General measures
- Relative rest
- Scrotal elevation/support
- Local Ice Therapy
- NSAIDs
XV. Management: Antibiotics (same management for Immunocompromised patients)
- Background
- Ciprofloxacin alone is not considered adequate coverage for Epididymitis (Chlamydia resistance)
- Children 2-14 yo should typically only be treated with Antibiotics if positive Urinalysis or Urine Culture
-
Gonorrhea and Chlamydia Treatment (empirically treat those between ages 14 and 35 years)
- Also treat all sexual contacts within last 60 days (see below)
- Gonorrhea management
- Ceftriaxone 500 mg IM/IV for 1 dose (1 gram IM/IV if weight > 150 kg, dose increased in 2020) OR
- Gentamicin 240 mg IM and Azithromycin 2 g orally for one dose OR
- Cefixime 800 mg orally once (an alternative but NOT recommended due to Antibiotic Resistance)
- Chlamydia management
- Doxycycline 100 mg twice daily for 10 days (preferred as of 2020) OR
- Azithromycin 1 g orally for 1 dose (NOT recommended) OR
- Levofloxacin 500 mg orally twice daily for 10 days
- Indicated for insertive anal intercourse (Chlamydia and enteric bacteric coverage)
- References
- Urinary tract source treatment (those not sexually active, or outside the 14-35 age range)
- First-line agents
- Ofloxacin 300 mg orally twice daily for 10 days OR
- Levofloxacin 500 mg orally once daily for 10 days
- Alternative agents
- Amoxicillin-Clavulanate (Augmentin) 875/125 orally twice daily OR
- Trimethoprim-Sulfamethoxazole (Septra, Bactrim) DS 1 orally twice daily for 10 days
- Avoid if local resistance >20%
- Refractory, severe cases
- Piperacillin-Tazobactam (Zosyn) 4.5 g IV every 6 hours OR
- Ceftriaxone 2 g IV every 24 hours
- First-line agents
- Combined risks of STD and urinary tract source (anal intercourse with either gender)
- Ceftriaxone 500 mg IM for 1 dose AND
- Ofloxacin or Levofloxacin at doses above
XVI. Management: Idiopathic Chronic Epididymitis
- Assumes negative evaluation as above and trial of empiric Antibiotics
- Initial trial for 2 weeks
- Failed general measures
- Tricyclic Antidepressants (e.g. Amitriptyline)
- Gabapentin (Neurontin)
- Consider Chronic Pain Management referral
- Consider referred pain
XVII. Management: Follow-up
- Child (ages <14 years old) with Epididymitis
- Structural or functional urinary abnormality in 39%
- Pediatric urology Consultation recommended
- Adult >50 years old with non-STD Epididymitis
- Evaluate for Benign Prostatic Hyperplasia (Bladder outlet obstruction)
-
Sexually Transmitted Infection
- Treat all sexual contacts within last 60 days (see Expedited Partner Treatment)
- Repeat screening for new STD in 3 months
XVIII. Prognosis
- Symptoms improve over first 2-3 days
- Inflammation and pain resolve over 2-4 weeks
XIX. Complications
XX. References
- (2019) Sanford Guide, accessed on IOS 9/27/2019
- Langan (2022) Am Fam Physician 106(2): 184-9 [PubMed]
- Luzzi (2001) BJU Int 87(8): 747-55 [PubMed]
- McConaghy (2016) Am Fam Physician 94(9): 723-6 [PubMed]
- Tojian (2009) Am Fam Physician 79:583-7 [PubMed]