Acute Epididymitis in Adults

Overview

Acute epididymitis is inflammation of the epididymis—the coiled tubular structure posterior to the testis responsible for sperm maturation and storage. It represents the most common cause of acute scrotal pain in adults, accounting for approximately 600,000 cases annually in the United States. [1] The condition presents a critical diagnostic challenge because it must be differentiated from testicular torsion, a surgical emergency requiring intervention within 6 hours to preserve testicular viability.

The epidemiology and microbiology of epididymitis follow a distinct bimodal age distribution. In sexually active men under 35 years, the condition is predominantly caused by sexually transmitted pathogens—Chlamydia trachomatis (most common) and Neisseria gonorrhoeae. [2] In contrast, men over 35 years or those with urological abnormalities typically harbor enteric Gram-negative organisms such as Escherichia coli, Klebsiella, Proteus, and Pseudomonas aeruginosa, which ascend from urinary tract colonization or infection. [3]

Clinical presentation is characterized by gradual onset unilateral scrotal pain and swelling developing over hours to days, often accompanied by dysuria, urethral discharge (in STI-related cases), or systemic features including fever. The key to management lies in three pillars: (1) urgent exclusion of testicular torsion using Doppler ultrasonography; (2) age- and risk-stratified empiric antibiotic therapy targeting likely pathogens; and (3) public health measures including partner notification and treatment for sexually transmitted cases. [4]

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Epidemiology

Incidence and Prevalence

Epididymitis is the most common cause of intrascrotal inflammation in adult men, with an estimated incidence of 25-65 cases per 10,000 males annually in industrialized nations. [5] Peak incidence follows a bimodal distribution correlating with different etiological patterns:

Approximately 80-90% of cases are unilateral at presentation, with bilateral involvement suggesting systemic infection, viral etiology (e.g., mumps), or non-infectious causes. [6]

Demographic Patterns

Race and Ethnicity: Chlamydial epididymitis shows higher incidence in African American and Hispanic populations in the United States, paralleling general STI prevalence disparities. [7]

Geographic Variation: Higher rates of epididymitis are observed in regions with elevated STI prevalence and limited access to screening programs.

Temporal Trends: Incidence has remained stable over the past two decades, though the proportion attributable to C. trachomatis has increased relative to gonococcal cases due to improved detection of asymptomatic chlamydial urethritis. [8]

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Aetiology and Risk Factors

Infectious Causes

The microbiology of epididymitis is age-dependent and reflects the route of infection:

Sexually Transmitted Pathogens (predominantly less than 35 years):

1. Chlamydia trachomatis (serovars D-K): Most common cause in young sexually active men, accounting for 50-60% of cases in this demographic. Often asymptomatic or associated with mild urethritis. [9]

2. Neisseria gonorrhoeae: Second most common STI cause. May present with purulent urethral discharge. Co-infection with C. trachomatis occurs in 20-40% of cases. [10]

3. Less common STI pathogens: Mycoplasma genitalium, Ureaplasma urealyticum, Trichomonas vaginalis. [11]

Enteric Organisms (predominantly > 35 years or with risk factors):

1. Escherichia coli: Most common enteric pathogen, accounting for 70-80% of cases in older men. [12]

2. Other Gram-negative rods: Pseudomonas aeruginosa (especially post-instrumentation), Klebsiella pneumoniae, Proteus mirabilis, Enterobacter species.

3. Gram-positive cocci: Enterococcus faecalis (associated with chronic bacteriuria, catheters).

Special Populations:

• MSM with insertive anal intercourse: Enteric organisms (E. coli, Haemophilus influenzae) ± concurrent STI pathogens. [13]
• Post-vasectomy: Congestive epididymitis (sterile inflammation) or secondary infection.
• Immunocompromised: Opportunistic organisms including fungi (Candida, Aspergillus), atypical mycobacteria.
• Endemic areas: Tuberculosis (insidious chronic epididymitis with "sterile pyuria"). [14]

Non-Infectious Causes

Chemical Epididymitis: Sterile inflammation caused by retrograde urine reflux through the vas deferens during increased intra-abdominal pressure (heavy lifting, straining). Typically self-limited.

Medication-Induced: Amiodarone is the classic culprit, causing dose-dependent epididymitis in 3-11% of patients on chronic therapy. Mechanism involves drug accumulation in epididymal tissue. [15]

Systemic Inflammatory Conditions: Behçet's disease, sarcoidosis, Henoch-Schönlein purpura.

Traumatic: Direct scrotal trauma with secondary inflammation.

Risk Factors

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Pathophysiology

Anatomical Considerations

The epididymis is a single, highly coiled 6-7 meter tubule condensed into a 4-5 cm structure divided into three regions:

1. Head (caput): Receives sperm from efferent ductules of the testis. Site of initial inflammation in most cases.
2. Body (corpus): Site of sperm maturation. Often involved in progressive disease.
3. Tail (cauda): Sperm storage reservoir; continuous with vas deferens. Can harbor chronic infection.

Blood supply derives from the testicular artery (deferential artery branch) and artery of the vas deferens, with venous drainage via the pampiniform plexus. This vascular arrangement allows hematogenous spread of infection, though ascending infection is far more common.

Mechanisms of Infection

Ascending Retrograde Infection (90-95% of cases):

1. Urethral colonization: Pathogens establish infection in the urethra (STI organisms) or colonize from bladder (enteric organisms).

2. Ascent via vas deferens: Bacteria ascend through the ejaculatory duct and vas deferens, facilitated by:

   • Reflux of infected urine during micturition or straining
   • Sexual activity (orgasm-associated ejaculatory duct pressures)
   • Loss of normal unidirectional flow

3. Epididymal invasion: Organisms proliferate in the tail, then progress to the body and head.

4. Inflammatory cascade: Bacterial invasion triggers:

   • Polymorphonuclear leukocyte infiltration
   • Cytokine release (IL-1β, IL-6, TNF-α)
   • Vascular dilation and increased permeability
   • Tissue edema and pain

5. Extension to testis: In 20-40% of cases, inflammation spreads to adjacent testicular tissue (epididymo-orchitis). [16]

Hematogenous Spread (less than 5% of cases):

Occurs in systemic infections (e.g., tuberculosis, brucellosis, viral infections such as mumps). Bloodborne organisms seed the epididymis via arterial supply.

Molecular Pathophysiology

Exam Detail: Chlamydial Epididymitis: C. trachomatis is an obligate intracellular bacterium that infects columnar epithelial cells. Following urethral infection, the organism ascends to the epididymis where it:

• Enters epididymal epithelial cells via endocytosis
• Replicates within membrane-bound vacuoles (inclusions)
• Triggers a predominantly lymphocytic inflammatory response
• Causes chronic inflammation via persistent infection and immune-mediated tissue damage
• Results in potential long-term sequelae including tubular fibrosis and obstruction

Host Immune Response: The severity of epididymitis depends on the balance between bacterial virulence factors and host defense:

• Innate immunity: Toll-like receptor (TLR) activation → NF-κB pathway → pro-inflammatory cytokine production
• Adaptive immunity: CD4+ T-cell responses are critical for bacterial clearance but may also mediate chronic inflammation and fibrosis
• Immunopathology: Persistent immune activation can lead to autoimmune orchitis in severe cases

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Clinical Presentation

Symptoms

The classical presentation of acute epididymitis features gradual onset of symptoms developing over hours to days, contrasting sharply with the sudden onset seen in testicular torsion:

Temporal Evolution:

• Hours 0-12: Mild, dull ache in hemiscrotum; patient may ignore initially
• Hours 12-24: Progressive pain and tenderness; difficulty walking
• Days 1-3: Peak pain and swelling; scrotal skin changes appear
• Days 3-7: Gradual improvement with appropriate antibiotics; persistence suggests complications

Clinical History: Key Questions

A focused history should address:

Pain Characteristics:

• "When did the pain start, and how quickly did it come on?" (Sudden = torsion; gradual = epididymitis)
• "Where exactly in the scrotum is the pain?" (Posterior = epididymis; central = testis)
• "Does the pain get better or worse with any position?" (Elevation traditionally taught to help, but unreliable)

Genitourinary Symptoms:

• "Any burning when you urinate or discharge from the penis?" (STI screening)
• "Difficulty passing urine or weak stream?" (BPH, obstruction)
• "Blood in urine or semen?" (Severity indicator)

Sexual and STI History:

• "Are you sexually active? New partner in the past 60 days?" (STI risk)
• "What methods do you use for contraception/STI prevention?" (Condom use)
• "Any history of STIs or current symptoms in your partner?" (Index case)
• "Do you have sex with men, women, or both?" (MSM = different pathogen risk)

Medical and Surgical History:

• "Any recent procedures on your bladder or prostate?" (Instrumentation)
• "Do you have a urinary catheter?" (Enteric organism risk)
• "Any history of prostate problems or urinary retention?" (Obstruction)
• "Previous episodes of epididymitis or testicular problems?" (Recurrence, anatomy)
• "Are you taking any medications?" (Amiodarone)

Trauma:

• "Any recent injury to the scrotum or groin?" (Traumatic epididymitis)

Physical Examination

General Inspection:

• Fever (temperature > 38°C suggests severe infection)
• Gait disturbance (antalgic, "waddling" due to scrotal pain)
• Positioning (reluctance to move, protective posturing)

Genital Examination (patient supine and standing):

1. External Inspection:

   • Scrotal skin: erythema, warmth, edema (inflammatory signs)
   • Asymmetry: affected side enlarged
   • Position: normal lie (unlike high-riding testis in torsion)
   • Urethral meatus: discharge (obtain swab before micturition)

2. Palpation (examine normal side first):

   • Epididymis: Posterolateral to testis
     • Normal: soft, non-tender, smooth
     • Epididymitis: indurated, exquisitely tender, enlarged (may feel like "bag of worms")
     • Document which part affected: head, body, tail, or diffuse
   • Testis:
     • Normal: smooth, ovoid, firm but not hard, non-tender
     • Epididymo-orchitis: enlarged, tender, loss of normal contour
   • Spermatic cord: tenderness suggests ascending inflammation
   • Reactive hydrocele: fluctuant swelling; may obscure palpation of testis/epididymis

3. Special Tests:

   • Cremasteric reflex: Stroke inner thigh → testis should elevate. Present in epididymitis, often absent in torsion. Sensitivity 80-90% for torsion detection. [17]
   • Prehn's sign: Manual elevation of affected testis → pain relief suggests epididymitis; no relief suggests torsion. CRITICAL: This sign has poor sensitivity (50-60%) and specificity (40-50%) and should NOT be used to rule out torsion. [18]
   • Blue dot sign: Transillumination shows blue nodule = torsion of appendix testis (pediatric, rarely seen in adults)

4. Digital Rectal Examination (in older men):

   • Prostatic tenderness, bogginess → concurrent prostatitis
   • Prostatic enlargement → BPH as predisposing factor

Abdominal Examination:

• Suprapubic tenderness (concurrent cystitis)
• Palpable bladder (urinary retention)
• Surgical scars (previous genitourinary surgery)

Key Clinical Differentiators: Epididymitis vs Testicular Torsion

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Red Flags and Emergent Considerations

Absolute Indications for Urgent Doppler Ultrasound

Complications Requiring Admission or Intervention

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Differential Diagnosis

The acute scrotum has a limited differential, but distinguishing between causes is critical due to vastly different management:

Surgical Emergencies (Do Not Miss)

1. Testicular Torsion

   • Features: Sudden severe pain, nausea/vomiting, high-riding testis, absent cremasteric reflex, decreased/absent Doppler flow
   • Age: Peak 12-18 years; can occur at any age
   • Management: Surgical detorsion within 6 hours (90% salvage rate); > 24 hours results in near-certain infarction
   • Discriminators: Onset timing, age, Doppler findings

2. Fournier's Gangrene

   • Features: Necrotizing fasciitis of perineum/scrotum, crepitus, rapidly spreading erythema, systemic toxicity
   • Risk factors: Diabetes, immunosuppression, perianal infection
   • Management: Immediate surgical debridement, broad-spectrum IV antibiotics
   • Discriminators: Skin findings, crepitus, rapid progression, systemic illness

3. Incarcerated/Strangulated Inguinal Hernia

   • Features: Inguinoscrotal mass, bowel sounds on auscultation, inability to reduce
   • Signs: Overlying skin erythema if strangulated, associated bowel obstruction symptoms
   • Management: Urgent surgical reduction/repair
   • Discriminators: Mass extends to inguinal canal, reducibility, imaging shows bowel

Inflammatory Conditions

4. Torsion of Testicular/Epididymal Appendix

   • Features: Gradual onset, localized upper pole tenderness, "blue dot sign" on transillumination
   • Age: Prepubertal > adults
   • Management: Conservative (NSAIDs, scrotal support); symptoms resolve in 3-10 days
   • Discriminators: Focal tenderness, less severe pain, self-limited course

5. Isolated Orchitis

   • Features: Testicular swelling and tenderness WITHOUT epididymal involvement
   • Causes: Viral (mumps, coxsackievirus, CMV, EBV), rarely bacterial without epididymitis
   • Management: Supportive care; antibiotics not indicated unless bacterial suspected
   • Discriminators: Systemic viral illness, bilateral in 30% (mumps), spares epididymis on exam/ultrasound

6. Epididymo-orchitis

   • Features: Combined epididymal and testicular involvement (20-40% of epididymitis cases progress to this)
   • Management: Same as isolated epididymitis
   • Discriminators: Exam and imaging show both structures involved

Benign Structural Abnormalities

7. Hydrocele

   • Features: Painless scrotal swelling, transilluminates, testis palpable within fluid
   • Types: Communicating (pediatric), non-communicating (adult), reactive (secondary to inflammation)
   • Management: Observation if asymptomatic; surgical repair if large/symptomatic
   • Discriminators: Painless, fluctuant, transilluminates, chronic course

8. Varicocele

   • Features: "Bag of worms" feeling in scrotum, worse when standing, decompresses when supine
   • Side: 90% left-sided (due to left testicular vein draining to renal vein at right angle)
   • Management: Observation unless infertility, pain, or testicular atrophy
   • Discriminators: Positional variation, painless, chronic, characteristic feel

9. Spermatocele

   • Features: Cystic swelling separate from and superior to testis, painless, transilluminates
   • Management: Observation unless symptomatic
   • Discriminators: Painless, cystic, distinct from testis, stable size

Malignancy

10. Testicular Cancer
    • Features: Painless, firm, non-transilluminating testicular mass; may present with dull ache
    • Age: Peak 15-35 years (seminoma, non-seminomatous germ cell tumors)
    • Red flag: Any firm testicular mass until proven otherwise
    • Management: Urgent urology referral, tumor markers (AFP, β-hCG, LDH), scrotal ultrasound (do NOT biopsy)
    • Discriminators: Painless hard mass intrinsic to testis, elevated tumor markers, suspicious ultrasound features

Other Causes

11. Trauma

    • History: Preceding blunt injury
    • Features: Ecchymosis, hematoma, testicular rupture (severe cases)
    • Management: Ice, analgesia; surgical exploration if rupture suspected
    • Discriminators: Clear trauma history, ecchymosis

12. Henoch-Schönlein Purpura (IgA Vasculitis)

    • Features: Palpable purpura on lower extremities, abdominal pain, arthritis, scrotal swelling (10-35% of boys)
    • Age: Predominantly pediatric
    • Management: Supportive; scrotal involvement may mimic torsion
    • Discriminators: Characteristic purpuric rash, systemic features

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Diagnostic Approach

Clinical Diagnosis

Diagnosis of epididymitis is primarily clinical, supported by laboratory and imaging studies. The 2021 CDC STI Treatment Guidelines define epididymitis by the presence of: [19]

1. Unilateral testicular/epididymal pain and tenderness
2. Palpable swelling of the epididymis
3. Duration > 1 day

Probable epididymitis requires at least one of the following additional findings:

• Urethral discharge or urethritis on examination
• Positive leukocyte esterase test or pyuria (≥10 WBC/hpf on urinalysis)
• Gram stain of urethral secretions showing WBCs

Laboratory Investigations

Testing Algorithm by Age/Risk:

• Age less than 35, sexually active: Urine NAAT (CT/GC), urinalysis, urethral swab if discharge, HIV/syphilis serology
• Age > 35 or risk factors: Urinalysis, urine culture, urine NAAT if sexually active, consider post-void residual
• MSM with insertive anal intercourse: Urine culture AND urine NAAT (CT/GC)
• All patients: If torsion not excluded clinically → Doppler ultrasound BEFORE laboratory workup delays care

Imaging

Scrotal Doppler Ultrasound: Gold standard imaging modality

Indications:

• Cannot clinically exclude testicular torsion
• Age less than 25 years (higher torsion risk)
• Diagnostic uncertainty
• Suspected complications (abscess, testicular infarction)
• Failure to improve on appropriate antibiotics after 48-72 hours
• Palpable mass (exclude malignancy)

Technique: High-frequency linear transducer (7.5-15 MHz); grayscale followed by color and spectral Doppler

Ultrasound Findings:

Sensitivity/Specificity:

• Epididymitis diagnosis: Sensitivity 70-88%, Specificity 88-90% [20]
• Torsion detection (absent flow): Sensitivity 86-100%, Specificity 97-100% [21]

Pitfalls:

• Early torsion (less than 4 hours): May have residual flow
• Intermittent torsion: Normal flow when detorsed
• Small testis: Technical difficulty assessing flow
• Epididymo-orchitis with severe inflammation: Rarely can cause venous congestion and appear as decreased arterial flow

When to Use MRI: Rarely indicated; reserve for:

• Indeterminate ultrasound findings
• Suspected testicular tumor with concurrent inflammation
• Assessment of scrotal wall involvement (Fournier's gangrene extent)

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Management

General Principles

1. Rule out testicular torsion first: If any clinical doubt, obtain immediate Doppler ultrasound. Do NOT delay imaging for laboratory results.

2. Empiric antibiotics: Initiate based on age, sexual history, and risk factors. Do not wait for culture results in acute cases.

3. Targeted therapy: Modify antibiotics once culture and NAAT results available.

4. Supportive care: Scrotal elevation, ice, NSAIDs form the foundation of symptomatic management.

5. Partner management: Essential for STI-related cases to prevent reinfection and ongoing transmission.

6. Follow-up: Ensure clinical improvement within 48-72 hours; persistent symptoms require re-evaluation.

Empiric Antibiotic Therapy

Selection is based on age-stratified and risk-stratified assessment of likely pathogens:

Regimen 1: Sexually Active Men less than 35 Years (STI Likely)

First-Line:

Ceftriaxone 500 mg IM as single dose
PLUS
Doxycycline 100 mg PO twice daily for 10-14 days

Rationale:

• Ceftriaxone provides coverage for N. gonorrhoeae including fluoroquinolone-resistant strains
• Doxycycline covers C. trachomatis (requires 7-day minimum, 10-14 days preferred for epididymitis to ensure tissue penetration)
• Covers co-infection (present in 20-40% of gonococcal urethritis cases)

Alternative (if ceftriaxone not available):

Cefixime 400 mg PO as single dose
PLUS
Doxycycline 100 mg PO twice daily for 10-14 days

If tetracycline allergy:

Ceftriaxone 500 mg IM single dose
PLUS
Levofloxacin 500 mg PO daily for 10 days (check local GC resistance patterns)

Regimen 2: Men > 35 Years or Enteric Organism Likely

Risk factors: BPH, urinary retention, recent instrumentation, catheterization, anatomical abnormalities

First-Line (fluoroquinolone):

Levofloxacin 500 mg PO once daily for 10-14 days

OR

Ofloxacin 300 mg PO twice daily for 10-14 days

Rationale:

• Excellent tissue penetration into epididymis and prostate
• Broad Gram-negative coverage including E. coli, Klebsiella, Proteus, Pseudomonas
• Also covers atypical organisms (Chlamydia, Mycoplasma)

Alternative (if fluoroquinolone contraindication or allergy):

Trimethoprim-sulfamethoxazole DS (160/800 mg) PO twice daily for 10-14 days

(Avoid if local E. coli resistance > 20%)

OR

Co-amoxiclav 875/125 mg PO twice daily for 10-14 days

(Less reliable for Gram-negatives; consider adding gentamicin 5 mg/kg IV once daily for first 3 days if severe)

Regimen 3: Men Who Have Sex with Men (MSM) with Insertive Anal Intercourse

Dual pathogen coverage:

Ceftriaxone 500 mg IM as single dose
PLUS
Levofloxacin 500 mg PO once daily for 10 days

Rationale: Covers both STI organisms and enteric pathogens (E. coli, H. influenzae) acquired via anal-genital contact

Special Situations

Suspected Pseudomonas (post-instrumentation, hospital-acquired, catheter-associated):

Ciprofloxacin 500 mg PO twice daily for 10-14 days

OR

Levofloxacin 750 mg PO once daily for 10-14 days

Suspected TB epididymitis (endemic area, chronic presentation, sterile pyuria, immunocompromised):

Refer to infectious disease for multidrug anti-TB therapy
Standard regimen: Rifampicin, isoniazid, pyrazinamide, ethambutol for 2 months, then rifampicin/isoniazid for 4 months

Severe infection requiring admission:

Ceftriaxone 1-2 g IV once daily
PLUS
Doxycycline 100 mg PO/IV twice daily

OR (if enteric organisms)

Piperacillin-tazobactam 4.5 g IV every 6 hours
OR
Ceftriaxone 2 g IV once daily + metronidazole 500 mg IV every 8 hours (if Fournier's suspected)

Supportive Care

Surgical Interventions

Indications for Urological Consultation:

1. Scrotal abscess: Requires incision and drainage (I&D) ± placement of drain
2. Pyocele: Aspiration or surgical drainage
3. Testicular infarction: May require orchiectomy if necrotic
4. Fournier's gangrene: Immediate wide debridement, may require multiple operations
5. Recurrent epididymitis: Consider epididymectomy (last resort after medical optimization)
6. Chronic epididymitis (> 6 weeks): Refractory to antibiotics; epididymectomy provides relief in 50-80%
7. Underlying anatomical abnormality: Vesicoureteral reflux, ectopic ureter (more common in pediatrics)

Partner Notification and Management

For STI-Related Epididymitis (critical public health measure):

1. Identify contacts: All sexual partners within 60 days of symptom onset

2. Partner notification:

   • Patient can notify partners directly (patient referral)
   • Provider-assisted referral (contact tracing)
   • Expedited partner therapy (EPT) where legal: Provide prescription/medication for partner without examination

3. Partner treatment:

   • Treat presumptively for gonorrhea and chlamydia (same regimen as index case)
   • Test partners for HIV, syphilis, other STIs
   • Advise abstinence until both partners complete treatment and are symptom-free

4. Documentation: Record partner notification in medical record

Follow-Up and Monitoring

Initial Follow-Up (48-72 hours):

• Phone contact or in-person if not improving
• Expected: Gradual pain reduction, decreased swelling
• Red flags: Worsening pain, fever, spreading erythema → re-evaluate for abscess or alternative diagnosis

Routine Follow-Up (1-2 weeks):

For STI-related cases:

• Test of cure NOT routinely recommended for chlamydia (if doxycycline used)
• Test of cure for gonorrhea: Urine NAAT 7 days after completion of therapy (documents eradication)
• Repeat HIV/syphilis testing at 3 months if initial negative
• Re-test for chlamydia/gonorrhea at 3 months (high reinfection rate: 10-15%)

For enteric organism cases:

• Urology referral if:
  • Recurrent episodes (≥2 in 12 months)
  • Incomplete response to antibiotics
  • Structural abnormality suspected (post-void residual > 100 mL, hydronephrosis)
  • Age > 50 with first episode (consider malignancy, obstruction)

Long-Term:

• Educate on recognition of recurrence
• STI prevention counseling (condom use, screening)
• Monitor for chronic epididymitis (persistent pain > 3-6 months)

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Disposition

Discharge Criteria (Outpatient Management)

Most patients (> 90%) can be managed as outpatients if ALL of the following:

✓ Testicular torsion excluded (clinically or by imaging) ✓ Hemodynamically stable, afebrile or low-grade fever (less than 38.5°C) ✓ Able to tolerate oral intake and medications ✓ Pain controlled with oral analgesics ✓ No signs of abscess or necrotizing infection ✓ Reliable patient with access to follow-up ✓ Safe home environment ✓ Understanding of warning signs

Discharge Instructions:

1. Complete full antibiotic course (critical even if symptoms improve)
2. Supportive care measures (elevation, ice, scrotal support)
3. Analgesics as prescribed
4. Sexual abstinence until treatment complete
5. Partner notification (if STI)
6. Return precautions (see below)
7. Follow-up appointment in 48-72 hours

Admission Criteria (Inpatient Management)

Admit if ANY of the following:

Return Precautions

Instruct patient to return immediately or call emergency services if:

⚠️ Worsening pain despite medications ⚠️ Fever > 38.5°C or chills/rigors ⚠️ Rapidly spreading redness or skin discoloration (black/purple) ⚠️ Skin blistering, crepitus (crackling sensation), foul odor ⚠️ Inability to urinate or severe urinary retention ⚠️ Scrotal swelling that continues to enlarge rapidly ⚠️ Systemic symptoms: confusion, severe weakness, shortness of breath ⚠️ No improvement in pain within 48-72 hours of antibiotics

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Special Populations

Prepubertal Children

Epidemiology: Epididymitis is uncommon in prepubertal boys (less than 5% of acute scrotum cases in this age group).

Etiology:

• Viral infection (mumps, enteroviruses)
• Bacterial UTI with ascending infection (often with anatomical abnormality)
• Trauma
• Idiopathic

Key Difference: HIGH index of suspicion for testicular torsion (accounts for 40-50% of acute scrotum in prepuberty). Always image if any diagnostic uncertainty.

Workup:

• Urinalysis and urine culture (all cases)
• Renal/bladder ultrasound to assess for vesicoureteral reflux, posterior urethral valves, ectopic ureter
• Voiding cystourethrogram (VCUG) if recurrent UTIs or structural abnormality suspected

Management:

• Antibiotics as for enteric organisms (adjust for weight)
• Mandatory urology and/or pediatric nephrology referral for anatomical evaluation

Elderly Men (> 65 Years)

Epidemiology: Increasing incidence due to:

• High prevalence of BPH (50% at age 60, 90% at age 85)
• Instrumentation (cystoscopy, catheterization)
• Immunosenescence

Pathogens: Predominantly enteric; consider atypical organisms in immunocompromised

Complications: Higher risk of:

• Abscess formation (10-15% vs 5-10% in younger men)
• Concurrent prostatitis
• Urosepsis

Management Considerations:

• Lower threshold for admission (comorbidities, polypharmacy)
• Renal dose adjustment of fluoroquinolones if eGFR less than 50 mL/min
• Assess for urinary retention (post-void residual)
• Urology referral for:
  • Investigation of obstruction (BPH, stricture, malignancy)
  • Consideration of transurethral resection of prostate (TURP) if recurrent
• Avoid fluoroquinolones if:
  • History of aortic aneurysm (increased rupture risk, FDA black box warning)
  • Severe tendinopathy risk
  • QTc prolongation

Immunocompromised Patients

Risk Groups: HIV/AIDS (CD4 less than 200), chemotherapy, solid organ transplant, chronic corticosteroids, biologics

Atypical Pathogens:

• Fungi: Candida, Aspergillus, Cryptococcus
• Mycobacteria: Mycobacterium tuberculosis, M. avium complex
• Parasites: Toxoplasma gondii (rare)

Workup:

• Broader microbiological investigation: AFB culture, fungal culture
• Consider early imaging (abscess risk higher)
• Blood cultures (fungemia, mycobacteremia)

Management:

• Broader empiric coverage; consider adding antifungal (fluconazole 400 mg loading, then 200 mg daily) if high risk
• Earlier surgical consultation (abscess formation more common)
• Infectious disease consultation for complex cases
• Higher threshold for admission

Amiodarone-Induced Epididymitis

Epidemiology: Occurs in 3-11% of men on chronic amiodarone therapy; dose-dependent.

Pathophysiology: Amiodarone accumulates in epididymal tissue → chemical inflammation → sterile epididymitis

Clinical Features:

• Bilateral in up to 50% (vs less than 10% in infectious epididymitis)
• Gradual onset, chronic course
• Afebrile, non-toxic
• Urinalysis normal (no pyuria)
• Negative cultures

Diagnosis: Clinical (exposure + bilateral involvement + sterile workup) + ultrasound showing epididymal enlargement without abscess

Management:

• Do NOT treat with antibiotics (ineffective and contributes to resistance)
• Supportive care (NSAIDs, scrotal support)
• Consider dose reduction or alternative antiarrhythmic (discuss with cardiology)
• Symptoms may take weeks to months to resolve after drug cessation
• Rarely, epididymectomy needed for refractory cases

Tuberculous Epididymitis

Epidemiology: More common in endemic areas (sub-Saharan Africa, South Asia); often seen in HIV co-infection

Clinical Features:

• Insidious onset (weeks to months)
• Painless or dull ache
• "Sterile pyuria" on urinalysis (WBCs present but standard bacterial cultures negative)
• Indurated, beaded epididymis on palpation
• May have draining sinus tracts in advanced cases

Associated Findings:

• Pulmonary TB (40-50% of cases)
• Genitourinary TB (kidney, bladder, prostate) in 80%

Workup:

• Three early-morning urine samples for AFB culture and PCR (GeneXpert MTB/RIF)
• Chest X-ray (pulmonary TB)
• HIV testing
• Urological imaging (CT urography) to assess kidney/ureter involvement
• Rarely, epididymal biopsy showing caseating granulomas

Management:

• Multidrug anti-TB therapy for 6 months:
  • "Intensive phase (2 months): Rifampicin, isoniazid, pyrazinamide, ethambutol"
  • "Continuation phase (4 months): Rifampicin, isoniazid"
• Longer duration (9-12 months) if extensive disease or HIV co-infection
• Monitor for treatment response (clinical improvement, negative cultures)
• Surgical intervention rarely needed (epididymectomy for residual mass/pain)

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Complications and Long-Term Outcomes

Acute Complications

Chronic Complications

Chronic Epididymitis (5-10% of cases):

• Definition: Persistent scrotal pain > 6 weeks despite appropriate antibiotic therapy
• Pathophysiology: Chronic inflammation, fibrosis, possible autoimmune component
• Clinical features: Dull ache, worse with activity; exam shows indurated, mildly tender epididymis
• Management:
  • Rule out persistent/recurrent infection (repeat cultures)
  • Prolonged course of antibiotics (4-6 weeks) if culture-positive
  • NSAIDs, neuropathic pain medications (gabapentin, amitriptyline)
  • Spermatic cord block (local anesthetic ± corticosteroid)
  • Epididymectomy as last resort (success rate 50-80%)

Male Infertility:

• Incidence: Unilateral epididymitis rarely causes infertility (less than 5%); bilateral or severe cases carry higher risk
• Mechanism: Tubular obstruction from fibrosis, immune-mediated damage to spermatogenesis, antisperm antibodies
• Prevention: Prompt treatment, complete antibiotic course, partner treatment (avoid reinfection)
• Evaluation: Semen analysis if fertility concerns; consider urology/reproductive endocrinology referral

Testicular Atrophy:

• Incidence: Rare (less than 2%) with isolated epididymitis; more common with severe epididymo-orchitis
• Mechanism: Vascular compromise, chronic inflammation
• Monitoring: Serial scrotal ultrasounds if severe initial presentation

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Prognosis

Treated Cases

Acute Resolution:

• Symptom improvement: Expected within 48-72 hours of appropriate antibiotics; full resolution typically 1-2 weeks
• Physical examination: Epididymal tenderness and swelling may persist for 2-4 weeks even with successful treatment
• Return to normal activity: Gradual increase; full activity including sexual intercourse after complete resolution (2-4 weeks)

Cure Rates:

• STI-related with appropriate therapy: > 95% cure with ceftriaxone + doxycycline [22]
• Enteric organism-related: > 90% cure with fluoroquinolones
• Failure to improve suggests:
  • Antibiotic resistance (repeat cultures)
  • Abscess formation (reimaging)
  • Alternative diagnosis (reconsider torsion, tumor, TB)
  • Non-adherence to treatment

Untreated or Inadequately Treated Cases

Complications:

• Abscess formation: 15-20% (vs 5-10% with treatment)
• Chronic epididymitis: 20-30% (vs 5-10% with treatment)
• Testicular infarction: Increased risk
• Infertility: Particularly with bilateral involvement or C. trachomatis (can cause silent scarring)

Recurrence

Recurrence Rates:

• Overall: 10-20% within 1 year
• STI-related: 15-25% (mostly due to reinfection from untreated partners)
• Enteric: 10-15% (underlying urological pathology often present)

Prevention of Recurrence:

• STI cases: Partner treatment, barrier contraception, regular STI screening
• Enteric cases: Investigate and treat underlying causes (BPH, chronic prostatitis, anatomical abnormalities)

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Prevention and Public Health

Primary Prevention

STI Prevention:

• Consistent and correct condom use (reduces gonorrhea/chlamydia transmission by 80-90%)
• Mutual monogamy with uninfected partner
• Regular STI screening for sexually active individuals:
  • Annual chlamydia/gonorrhea screening for sexually active men less than 25 years (CDC recommendation)
  • More frequent screening (every 3-6 months) for MSM or those with multiple partners

Urological Health:

• Prompt treatment of UTIs
• Avoid unnecessary urinary catheterization
• Proper catheter care if indwelling catheter required
• Management of BPH to prevent urinary retention
• Pre-procedural antibiotic prophylaxis for genitourinary instrumentation in high-risk patients

Secondary Prevention

Early Detection and Treatment:

• Low threshold for evaluation of scrotal pain
• Rapid access to STI testing for at-risk populations
• Partner notification and expedited partner therapy to interrupt transmission chains

Screening Programs:

• Targeted chlamydia screening in high-prevalence populations reduces epididymitis incidence by estimated 20-30%

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Key Guidelines and Recommendations

CDC Sexually Transmitted Infections Treatment Guidelines (2021)

Epididymitis Most Likely Caused by STI (less than 35 years, sexually active): [19]

• Ceftriaxone 500 mg IM × 1 PLUS doxycycline 100 mg PO BID × 10 days

Epididymitis Most Likely Caused by Enteric Organisms (> 35 years or risk factors):

• Levofloxacin 500 mg PO daily × 10 days OR ofloxacin 300 mg PO BID × 10 days

MSM with Insertive Anal Intercourse:

• Ceftriaxone 500 mg IM × 1 PLUS levofloxacin 500 mg PO daily × 10 days

European Association of Urology (EAU) Guidelines on Urological Infections (2023)

Diagnostic Recommendations:

• Doppler ultrasound if torsion cannot be excluded clinically (Strong recommendation)
• Urine culture in all cases (Strong recommendation)
• STI testing (NAAT for CT/GC) based on sexual history and age (Strong recommendation)

Treatment Recommendations:

• Empiric antibiotic therapy initiated promptly after specimen collection
• Duration: Minimum 10 days, up to 14 days for severe cases
• Follow-up assessment at 2-3 days to ensure improvement

American Urological Association (AUA) Best Practice Statement

Key Points:

• Epididymitis is a clinical diagnosis supported by laboratory and imaging
• Testicular torsion must be excluded in all cases of acute scrotum
• Age-based empiric antibiotic selection is appropriate
• Partner notification is mandatory for STI-related cases
• Recurrent epididymitis warrants urological investigation

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Exam-Focused Content

Common Viva Questions and Model Answers

Q1: "A 23-year-old man presents with 2 days of left scrotal pain and swelling. How would you approach this patient?"

Model Answer: "This is acute scrotal pain in a young man, so my primary concern is to exclude testicular torsion, which is a urological emergency. I would take a focused history asking about the onset—sudden versus gradual—any urinary symptoms, sexual history, and previous episodes. On examination, I would assess testicular lie, presence of cremasteric reflex, and whether the epididymis or testis is predominantly tender. If I cannot confidently exclude torsion clinically, I would arrange urgent Doppler ultrasound before any other investigations.

Assuming epididymitis is the working diagnosis, in a 23-year-old sexually active male, the most likely pathogens are Chlamydia trachomatis and Neisseria gonorrhoeae. I would send first-void urine for NAAT testing for both organisms, perform urinalysis to look for pyuria, and if there's urethral discharge, obtain a swab for Gram stain and culture.

For empiric treatment, following CDC 2021 guidelines, I would give ceftriaxone 500 mg intramuscularly as a single dose plus doxycycline 100 mg twice daily for 10 days. I would also provide supportive care with scrotal elevation, ice, and NSAIDs, counsel on sexual abstinence until treatment completion, and arrange partner notification and treatment. Follow-up in 48-72 hours is essential to ensure improvement."

Q2: "What are the key differences between epididymitis and testicular torsion?"

Model Answer: "The critical differences are:

Onset: Epididymitis has gradual onset over hours to days, while torsion is sudden, often waking the patient from sleep.

Age: Epididymitis peaks in sexually active young adults and older men, while torsion is most common in adolescents aged 12-18 years.

Associated symptoms: Epididymitis often has urinary symptoms like dysuria or discharge, while torsion typically has nausea and vomiting.

Examination: In epididymitis, the cremasteric reflex is usually present, the testis has normal lie, and tenderness is maximal posteriorly over the epididymis. In torsion, the cremasteric reflex is absent in 90%, the testis is high-riding with horizontal lie, and there's diffuse testicular tenderness.

Doppler ultrasound: This is the definitive test—epididymitis shows increased blood flow with epididymal hyperemia, while torsion shows absent or markedly decreased testicular blood flow.

The key is that if there's any diagnostic uncertainty, you must obtain urgent imaging because the window for testicular salvage in torsion is only 6 hours, and outcomes are time-dependent."

Q3: "How does age influence the microbiology and treatment of epididymitis?"

Model Answer: "Age is the primary determinant of likely pathogens and therefore guides empiric antibiotic selection.

Under 35 years and sexually active: The predominant organisms are sexually transmitted—Chlamydia trachomatis is most common, followed by Neisseria gonorrhoeae. Treatment is ceftriaxone 500 mg IM once plus doxycycline 100 mg twice daily for 10 days. This regimen covers both organisms and accounts for the high rate of co-infection.

Over 35 years or those with urological risk factors like BPH, catheterization, or recent instrumentation: Enteric Gram-negative organisms predominate, especially E. coli. Treatment is with fluoroquinolones—either levofloxacin 500 mg daily or ofloxacin 300 mg twice daily for 10 days—which have excellent tissue penetration and Gram-negative coverage.

Special case—MSM with insertive anal intercourse: These patients can have both STI organisms and enteric pathogens from anal-genital contact, so they require dual coverage with ceftriaxone plus levofloxacin.

The key is that this age-based approach allows effective empiric therapy while awaiting culture and NAAT results, which can take 2-3 days."

High-Yield Facts for Examinations

Viva Point: Opening Statement: "Acute epididymitis is inflammation of the epididymis, the most common cause of acute scrotal pain in adults, characterized by gradual onset unilateral pain and swelling. The critical first step is to exclude testicular torsion using clinical assessment and Doppler ultrasound if needed. Microbiology is age-dependent: sexually transmitted organisms (C. trachomatis, N. gonorrhoeae) in men under 35, and enteric Gram-negatives (E. coli) in older men or those with urological abnormalities."

Key Statistics to Quote:

• Incidence: 600,000 cases/year in US; 25-65 per 10,000 males
• C. trachomatis: 50-60% of cases in sexually active men less than 35 years
• E. coli: 70-80% of cases in men > 35 years
• Testicular salvage in torsion: 90% if detorsion within 6 hours; less than 10% if > 24 hours
• Doppler ultrasound sensitivity for torsion: 86-100%
• Chronic epididymitis rate: 5-10% with treatment vs 20-30% without

Key Treatment Principles:

1. Rule out torsion (clinical exam + Doppler if doubt)
2. Empiric antibiotics based on age (less than 35: ceftriaxone + doxycycline; > 35: levofloxacin)
3. Supportive care (elevation, ice, NSAIDs, rest)
4. Partner notification for STI cases
5. Follow-up at 48-72 hours

Classifications:

• By etiology: STI-related vs enteric vs non-infectious (chemical, drug-induced)
• By duration: Acute (less than 6 weeks) vs chronic (> 6 weeks)
• By extent: Isolated epididymitis vs epididymo-orchitis

Common Pitfalls and Mistakes

❌ Mistake 1: Relying on Prehn's sign to rule out torsion ✅ Correct: Prehn's sign has poor sensitivity/specificity; always use Doppler ultrasound if torsion cannot be confidently excluded clinically

❌ Mistake 2: Treating all patients with the same antibiotic regimen ✅ Correct: Use age-stratified and risk-stratified approach: STI coverage for less than 35y sexually active; enteric coverage for > 35y or risk factors

❌ Mistake 3: Treating amiodarone-induced epididymitis with antibiotics ✅ Correct: This is chemical/sterile inflammation; antibiotics are ineffective. Supportive care ± amiodarone dose reduction

❌ Mistake 4: Failing to provide partner notification for STI cases ✅ Correct: Partner treatment is essential to prevent reinfection and ongoing transmission; all partners in past 60 days should be treated

❌ Mistake 5: Inadequate antibiotic duration ✅ Correct: Minimum 10 days required for epididymitis (longer than uncomplicated urethritis) to ensure adequate tissue penetration and bacterial eradication

❌ Mistake 6: Discharging without clear return precautions ✅ Correct: Educate on warning signs (worsening pain, fever, spreading erythema, no improvement in 48-72h) that require immediate re-evaluation

❌ Mistake 7: Missing Fournier's gangrene in early stages ✅ Correct: High suspicion in diabetic or immunocompromised patients with scrotal pain; look for crepitus, skin discoloration, systemic toxicity

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Patient Education and Shared Decision-Making

Explaining the Diagnosis

Lay Explanation: "You have an infection and inflammation of the epididymis, which is the coiled tube at the back of your testicle that stores and carries sperm. This is the most common cause of testicular pain in adult men. In your case, based on your age and sexual history [or: medical history], the infection is most likely caused by [sexually transmitted bacteria / bacteria from your urinary tract]. This is treated with antibiotics and usually gets better within a few days to a couple of weeks."

Addressing Common Concerns:

• "Is this testicular torsion?": "We've ruled out torsion, which is a surgical emergency, through your examination and ultrasound. Torsion has different features—it comes on very suddenly, and the blood flow to the testicle is cut off. Your ultrasound shows increased blood flow, which is consistent with inflammation from infection, not torsion."

• "Will this affect my fertility?": "Isolated one-sided epididymitis rarely causes infertility. The risk is higher if the infection is severe, involves both sides, or if it's not treated properly. That's why it's very important to complete the full course of antibiotics and have your partner treated if this is sexually transmitted, to avoid reinfection."

• "How did I get this?": Age-appropriate explanation based on likely etiology (STI vs enteric)

Self-Care Instructions

Written Discharge Instructions:

1. Medications:

   • Take ALL antibiotics as prescribed, even if you feel better (typical course: 10-14 days)
   • Pain relievers: [Ibuprofen 400-600 mg every 6-8 hours with food] AND/OR [Acetaminophen 650-1000 mg every 6 hours]
   • Do not stop antibiotics early—this can lead to recurrence or antibiotic resistance

2. Supportive Care:

   • Wear supportive underwear (athletic supporter or snug briefs) at all times
   • When lying down, elevate your scrotum on a rolled towel
   • Apply ice packs wrapped in a towel for 20 minutes, 3-4 times daily (do not apply ice directly to skin)
   • Rest for the first 2-3 days; avoid heavy lifting, strenuous exercise, and prolonged standing for 1-2 weeks

3. Activity Restrictions:

   • No sexual activity until you complete treatment and your symptoms are fully resolved
   • Gradual return to normal activities as pain allows
   • Avoid sports and heavy exercise for at least 1-2 weeks

4. Partner Management (if STI-related):

   • Notify all sexual partners in the past 60 days—they need testing and treatment
   • Your partners should be treated even if they have no symptoms
   • Use condoms consistently in the future to prevent STIs
   • Get tested for other STIs including HIV and syphilis

5. Follow-Up:

   • Call or return in 48-72 hours if your symptoms are not improving
   • Routine follow-up appointment in 1-2 weeks [scheduled date/time]

Warning Signs to Return Immediately

"Go to the emergency department or call 911 if you develop":

⚠️ Worsening pain that doesn't improve with pain medications ⚠️ Fever above 101°F (38.5°C) or shaking chills ⚠️ Rapidly spreading redness, skin discoloration (purple/black), or foul smell ⚠️ Skin blistering or crackling sensation (crepitus) in the scrotum ⚠️ Unable to urinate or severe difficulty urinating ⚠️ Swelling that rapidly worsens or spreads to your abdomen/thigh ⚠️ Feeling very unwell, confused, dizzy, or extremely weak ⚠️ No improvement in pain or swelling after 3 days of antibiotics

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References

1. Trojian TH, Lishnak TS, Heiman D. Epididymitis and orchitis: an overview. Am Fam Physician. 2009;79(7):583-587.

2. Workowski KA, Bachmann LH, Chan PA, et al. Sexually Transmitted Infections Treatment Guidelines, 2021. MMWR Recomm Rep. 2021;70(4):1-187. doi:10.15585/mmwr.rr7004a1

3. Tracy CR, Steers WD, Costabile R. Diagnosis and management of epididymitis. Urol Clin North Am. 2008;35(1):101-108. doi:10.1016/j.ucl.2007.09.013

4. Pilatz A, Altinkilic B, Köhler E, et al. Color Doppler ultrasound imaging in acute scrotal pain. Urol Int. 2013;90(3):270-275. doi:10.1159/000343423

5. Nickel JC, Siemens DR, Nickel KR, Downey J. The patient with chronic epididymitis: characterization of an enigmatic syndrome. J Urol. 2002;167(4):1701-1704.

6. McConaghy JR, Panchal B. Epididymitis: an overview. Am Fam Physician. 2016;94(9):723-726.

7. Centers for Disease Control and Prevention. Sexually Transmitted Disease Surveillance 2020. Atlanta: U.S. Department of Health and Human Services; 2021.

8. Miller WC, Ford CA, Morris M, et al. Prevalence of chlamydial and gonococcal infections among young adults in the United States. JAMA. 2004;291(18):2229-2236. doi:10.1001/jama.291.18.2229

9. Horner P, Blee K, O'Mahony C, et al. 2015 UK National Guideline on the management of non-gonococcal urethritis. Int J STD AIDS. 2016;27(2):85-96. doi:10.1177/0956462415586675

10. Rietmeijer CA, Mettenbrink CJ. Recalibrating the Gram stain diagnosis of male urethritis in the era of nucleic acid amplification testing. Sex Transm Dis. 2012;39(1):18-20. doi:10.1097/OLQ.0b013e3182354da3

11. Manhart LE, Broad JM, Golden MR. Mycoplasma genitalium: should we treat and how? Clin Infect Dis. 2011;53 Suppl 3:S129-S142. doi:10.1093/cid/cir702

12. Lipsky BA, Byren I, Hoey CT. Treatment of bacterial prostatitis. Clin Infect Dis. 2010;50(12):1641-1652. doi:10.1086/652861

13. Luzzi GA, O'Brien TS. Acute epididymitis. BJU Int. 2001;87(8):747-755. doi:10.1046/j.1464-410x.2001.02192.x

14. Figueiredo AA, Lucon AM, Srougi M. Urogenital tuberculosis. Microbiol Spectr. 2017;5(1). doi:10.1128/microbiolspec.TNMI7-0015-2016

15. Chua ME, Escusa KG, Luna S, et al. Revisiting overt and subclinical epididymal involvement in mumps. Andrologia. 2017;49(5). doi:10.1111/and.12644

16. Schuppe HC, Pilatz A, Hossain H, et al. Urogenital infection as a risk factor for male infertility. Dtsch Arztebl Int. 2017;114(19):339-346. doi:10.3238/arztebl.2017.0339

17. Nelson CP, Williams JF, Bloom DA. The cremasteric reflex: a useful but imperfect sign in testicular torsion. J Pediatr Surg. 2003;38(8):1248-1249. doi:10.1016/s0022-3468(03)00280-x

18. Mellick LB, Sinex JE, Gibson RW, Mears K. A systematic review of testicle survival time after a torsion event. Pediatr Emerg Care. 2019;35(12):821-825. doi:10.1097/PEC.0000000000001287

19. Centers for Disease Control and Prevention. Epididymitis. In: 2021 STI Treatment Guidelines. https://www.cdc.gov/std/treatment-guidelines/epididymitis.htm. Published 2021.

20. Dogra VS, Gottlieb RH, Oka M, Rubens DJ. Sonography of the scrotum. Radiology. 2003;227(1):18-36. doi:10.1148/radiol.2271001744

21. Kalfa N, Veyrac C, Lopez M, et al. Multicenter assessment of ultrasound of the spermatic cord in children with acute scrotum. J Urol. 2007;177(1):297-301. doi:10.1016/j.juro.2006.08.128

22. Geisler WM, Uniyal A, Lee JY, et al. Azithromycin versus doxycycline for urogenital Chlamydia trachomatis infection. N Engl J Med. 2015;373(26):2512-2521. doi:10.1056/NEJMoa1502599

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Summary: Quick Clinical Decision Tool

Step 1: Exclude Testicular Torsion

• Sudden onset, absent cremasteric reflex, high-riding testis → Urgent Doppler US + Urology
• Any diagnostic uncertainty → Doppler US

Step 2: Determine Likely Pathogen (Age-Based)

• less than 35 years, sexually active → STI (CT/GC) → Ceftriaxone 500mg IM + Doxycycline 100mg BID × 10d
• > 35 years OR urological risk → Enteric (E. coli) → Levofloxacin 500mg daily × 10d
• MSM, insertive anal sex → Both → Ceftriaxone 500mg IM + Levofloxacin 500mg daily × 10d

Step 3: Supportive Care + Follow-Up

• Scrotal elevation, ice, NSAIDs, rest
• Partner notification if STI
• Review at 48-72h; re-evaluate if not improving

Step 4: Admit If

• Abscess, Fournier's, sepsis, intractable pain, unable to take PO, uncertain diagnosis