How should acute orchitis presenting with scrotal pain, swelling, and possible fever be evaluated and managed?

Evaluation and Management of Acute Orchitis

Acute orchitis presenting with scrotal pain, swelling, and fever should be evaluated urgently with scrotal ultrasound to exclude testicular torsion, followed by targeted antimicrobial therapy based on age and risk factors, with most cases in adults caused by bacterial epididymo-orchitis requiring empiric antibiotics while viral orchitis (primarily mumps) is managed supportively. 1, 2

Immediate Diagnostic Priorities

The first critical step is to exclude testicular torsion, which requires surgical intervention within 6-8 hours to prevent testicular loss. 2, 3

Key Clinical Distinguishing Features

• Orchitis typically presents with gradual onset of pain over hours to days, whereas torsion presents with abrupt, severe pain 1, 4
• Fever is common in orchitis (often >38.5°C) but less typical in torsion 5
• Pain relief with testicular elevation (positive Prehn sign) suggests epididymo-orchitis rather than torsion 2
• The cremasteric reflex is typically intact in orchitis but absent in torsion 4

Mandatory Imaging

Perform urgent Duplex Doppler ultrasound with grayscale, color Doppler, and power Doppler if clinical suspicion for torsion cannot be excluded. 1, 2

• In orchitis, ultrasound shows increased testicular vascularity on color Doppler, whereas torsion shows decreased or absent flow 1, 6
• Look for enlarged epididymis with increased blood flow, present in up to 90% of bacterial cases 1, 4
• Scrotal wall thickening and hydrocele are common findings in inflammatory conditions 1, 6
• Up to 20% of epididymitis cases have concomitant orchitis 1

Microbiological Evaluation

The diagnostic approach differs dramatically by age, as pathogens vary significantly between younger and older men. 1

For Men <35 Years of Age

Sexually transmitted pathogens (Chlamydia trachomatis and Neisseria gonorrhoeae) are the primary causes. 1, 4

• Obtain urethral swab or first-void urine for NAAT testing for C. trachomatis and N. gonorrhoeae, as these are the most sensitive diagnostic tests 1
• Urethral Gram stain can provide rapid diagnosis of gonococcal urethritis 1, 4
• Urinalysis and urine culture should be obtained but may be normal 4

For Men >35 Years of Age

Coliform bacteria (E. coli, Pseudomonas, Enterococcus) similar to urinary tract pathogens are the primary causes. 1, 4

• Obtain midstream urine for culture and sensitivity 1
• Blood cultures if systemically unwell with high fever or signs of sepsis 7

Special Considerations for Viral Orchitis

Mumps orchitis should be considered in any unvaccinated or incompletely vaccinated male presenting 4-11 days after parotitis, though parotitis may be absent in up to 18% of cases. 8, 5

• Obtain mumps IgM serology or acute and convalescent IgG titers for diagnosis 1
• Other viral causes include Coxsackie virus, EBV, VZV, and rubella, though these are uncommon 1

Empiric Antimicrobial Therapy

Treatment should be initiated immediately after diagnostic specimens are obtained, targeting the most likely pathogens based on age and risk factors. 1, 4

For Suspected Sexually Transmitted Infection (<35 Years)

Administer ceftriaxone 1000 mg IM/IV single dose PLUS doxycycline 100 mg orally twice daily for 7 days. 1, 2

• This regimen covers both N. gonorrhoeae and C. trachomatis 1
• Alternative for C. trachomatis: azithromycin 1.0-1.5 g orally as single dose, though doxycycline is preferred 1
• For persistent symptoms after doxycycline, consider azithromycin 500 mg on day 1, then 250 mg daily for 4 days to cover Mycoplasma genitalium 1

For Suspected Enteric Pathogens (>35 Years)

Administer fluoroquinolone therapy: levofloxacin 500 mg orally once daily for 10 days OR ofloxacin 200 mg orally twice daily for 10 days. 1, 4

• Alternative: cephalosporin or trimethoprim-sulfamethoxazole based on local resistance patterns 4

Adjunctive Supportive Care

All patients require supportive measures regardless of etiology. 4, 5

• Bed rest with scrotal support and elevation 4, 5
• NSAIDs for pain and inflammation (e.g., ibuprofen or naproxen) 5
• Local cooling with ice packs may provide symptomatic relief 5

Indications for Surgical Intervention

Surgery is required when conservative management fails or complications develop. 7

Staging System for Surgical Decision-Making

Stage 1 (No surgery needed): Palpable differentiation between epididymis and testis, no hydrocele, no abscess—treat with antibiotics alone 7

Stage 2 (Surgery in 14.6% of cases): Palpable differentiation between epididymis and testis, hydrocele present, small abscesses—attempt conservative therapy for 48-72 hours, then operate if no improvement 7

Stage 3 (Surgery in majority): No palpable differentiation between epididymis and testis, with or without malacia, hydrocele present, abscesses of any size—proceed to surgery if no clinical improvement within 48-72 hours 7

Specific Surgical Indications

• Lack of clinical improvement after 48-72 hours of appropriate antibiotics 7
• Suspected testicular abscess or pyocele 6, 7
• Testicular infarction 1, 6
• Inability to exclude torsion clinically or radiographically 2, 3

Management of Viral (Mumps) Orchitis

Mumps orchitis is managed supportively, as no specific antiviral therapy exists. 8, 5

• Hospitalization is often required for severe cases with high fever and marked swelling 5
• NSAIDs, scrotal support, and local cooling are the mainstays of treatment 5
• Empiric antibiotics are often given initially because bacterial orchitis cannot be excluded at presentation 5
• Fever typically resolves within 3-6 days of supportive care 5
• Testicular atrophy occurs in up to 40% of cases, threatening future fertility 8

Critical Pitfalls to Avoid

Do not delay imaging or surgical consultation when torsion cannot be excluded clinically, as the 6-8 hour window for testicular salvage is absolute 2, 3

Do not assume normal urinalysis excludes epididymo-orchitis, as urinalysis may be normal in sexually transmitted cases 4

Do not forget to consider mumps in unvaccinated patients, even without parotitis, as orchitis may be the presenting manifestation 8, 5

Do not fail to obtain tissue culture if surgery is performed, as fungal (Blastomyces, Histoplasma, Coccidioides) and mycobacterial causes require specific media and prolonged incubation 1

Do not discharge patients without clear return precautions, as complications including abscess formation, testicular infarction, and chronic pain can develop 6, 7

Follow-Up and Monitoring

Arrange follow-up within 48-72 hours to assess clinical response to therapy. 4, 7

• Repeat ultrasound at 2-4 months post-treatment to assess for complications including testicular atrophy, chronic hydrocele, or calcifications 6
• Complete resolution occurs in approximately 50% of cases, while the remainder develop post-inflammatory sequelae 6
• Counsel patients about potential fertility implications, particularly after mumps orchitis 8