What are the possible causes and recommended evaluation and management for a constant dull bilateral testicular ache in an adult male?

Bilateral Testicular Dull Ache: Evaluation and Management

Most Likely Diagnosis

Bilateral epididymitis/epididymo-orchitis is the leading cause of constant bilateral testicular pain in adults, particularly in sexually active men under 35 years, and should be your primary working diagnosis. 1

Immediate Diagnostic Workup

Clinical Assessment Priority

• Determine onset pattern: Gradual onset over hours to days strongly favors epididymitis, while sudden severe pain suggests torsion (though bilateral torsion is rare at 2% of cases) 2, 1
• Age matters critically: In men over 25 years, epididymitis accounts for approximately 600,000 cases annually in the US and is overwhelmingly the most common cause 2
• Sexual history is essential: In men under 35 years, Chlamydia trachomatis or Neisseria gonorrhoeae are the primary pathogens; men practicing receptive anal intercourse may have enteric organisms 1

Required Laboratory Testing

• Urethral Gram stain: Look for >5 polymorphonuclear leukocytes per oil immersion field to confirm urethritis 1
• Nucleic acid amplification test (NAAT): For N. gonorrhoeae and C. trachomatis 1
• Urinalysis: Though normal urinalysis does not exclude epididymitis 2

Imaging Protocol

Order duplex Doppler ultrasound of bilateral scrotum immediately - this is the first-line imaging with 96-100% sensitivity for detecting torsion and will show characteristic findings for epididymitis 1, 3

The ultrasound must include:

• Grayscale examination: Assess for enlarged epididymis, testicular homogeneity, scrotal wall thickening, and hydrocele 2, 3
• Color Doppler: Epididymitis shows enlarged epididymis with increased blood flow (sensitivity near 100% for inflammation), while torsion shows decreased or absent flow 2, 3
• Power Doppler: More sensitive for slow-flow states, particularly useful as an adjunct 3

Management Based on Diagnosis

If Epididymitis is Confirmed (Most Likely)

For sexually active men under 35 years:

• Ceftriaxone 250 mg IM once PLUS Doxycycline 100 mg orally twice daily for 10 days 1

For men over 35 years or suspected enteric organisms:

• Ofloxacin 300 mg orally twice daily for 10 days OR Levofloxacin 500 mg orally once daily for 10 days 1

Adjunctive measures:

• Bed rest, scrotal elevation, and analgesics until inflammation subsides 2
• NSAIDs combined with antibiotics may provide additional benefit 4

Critical Red Flags Requiring Urgent Urological Consultation

Proceed directly to emergency urological evaluation if:

• Sudden onset of severe pain (even if bilateral) - bilateral torsion occurs in 2% of cases and requires surgical intervention within 6-8 hours 1
• Absent testicular blood flow on Doppler - this is testicular torsion until proven otherwise 2
• High clinical suspicion for torsion despite imaging - do not let imaging delay surgical exploration 1

Important Differential Diagnoses to Exclude

Testicular Tumors

• Must be excluded if swelling and tenderness persist after completing antimicrobial therapy 1
• Testicular cancer is most common in men 20-35 years and presents as painless mass in 99% of cases, though can cause dull ache 5
• If mass is palpated or ultrasound shows intratesticular mass, refer to urology for orchiectomy 5

Viral Orchitis

• Consider mumps orchitis if bilateral involvement occurs in context of systemic viral illness 1
• Usually presents with fever and parotid swelling 1

Chronic Testicular Pain Syndrome

• If pain persists >3 months despite treatment, consider chronic testicular pain syndrome 6
• May require multidisciplinary pain management, though 86.2% of patients experience ≥50% pain reduction with microsurgical denervation of spermatic cord 6

Common Pitfalls to Avoid

• Do not assume bilateral pain excludes torsion - bilateral or sequential torsion occurs in 2% of cases and is a surgical emergency 1
• Do not rely solely on normal urinalysis - it does not exclude either epididymitis or torsion 2
• Do not delay imaging in older patients - while torsion is rare over age 35, epididymitis can progress to testicular infarction if untreated 2, 3
• Do not miss the 6-8 hour window - if torsion is suspected, testicular viability is compromised beyond this timeframe 2, 1

Follow-Up Requirements

• Reassess in 48-72 hours to ensure clinical improvement on antibiotics 1
• Re-examine after completing antimicrobial therapy to exclude testicular tumor if swelling persists 1
• Consider repeat ultrasound in 6-8 weeks if any indeterminate findings were noted initially 2