What are the causes and treatment options for right-sided testicle pain?

Right-Sided Testicle Pain: Causes and Management

Immediate duplex Doppler ultrasound of the scrotum is the essential first step for any acute testicular pain to rule out testicular torsion, which requires surgical intervention within 6-8 hours to prevent permanent testicular loss. 1, 2

Immediate Triage: Rule Out Surgical Emergency

The most critical distinction is identifying testicular torsion, which is a surgical emergency with a narrow window for salvage:

• Testicular torsion presents with sudden, severe unilateral testicular pain, often without preceding trauma or infection 1, 2
• More common in adolescents and young men (bimodal distribution: neonates and postpubertal boys) 2
• If clinical suspicion is high (sudden severe pain, negative Prehn sign), proceed directly to emergency urological consultation without waiting for imaging 2, 3
• Duplex Doppler ultrasound shows decreased/absent blood flow and the pathognomonic "whirlpool sign" of twisted spermatic cord (96-100% sensitivity) 1, 2
• Surgical detorsion must occur within 6-8 hours of symptom onset to prevent permanent ischemic damage 2

Critical Pitfall

False-negative Doppler can occur with partial torsion or intermittent torsion (torsion-detorsion), so if clinical suspicion remains high despite normal imaging, still consult urology emergently 1, 2

Most Common Cause: Epididymitis/Epididymo-orchitis

In adults and adolescents, epididymitis is the most common cause of acute testicular pain (approximately 600,000 cases annually in the US) 1:

Clinical Features

• Gradual onset of unilateral testicular pain and tenderness 1, 2
• Palpable swelling of epididymis, hydrocele often present 1
• May have abnormal urinalysis (though normal urinalysis does not exclude diagnosis) 2
• Ultrasound shows enlarged epididymis with increased color Doppler flow 1

Diagnostic Workup

Before initiating empiric antibiotics, obtain: 1

• Gram stain of urethral exudate (>5 PMNs per oil immersion field indicates urethritis)
• Nucleic acid amplification test or culture for N. gonorrhoeae and C. trachomatis
• First-void urine for leukocytes if urethral Gram stain negative
• Syphilis serology and HIV testing

Treatment Algorithm

For men <35 years or sexually active men (likely STI-related): 1, 3

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

For men >35 years, enteric organisms suspected, or antibiotic allergies: 1, 3

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

Adjunctive therapy for all patients: 1

• Bed rest, scrotal elevation, and analgesics until fever and inflammation subside

Follow-Up Requirements

• If no improvement within 3 days, reevaluate both diagnosis and therapy 1
• If swelling/tenderness persists after completing antibiotics, comprehensive evaluation needed for: tumor, abscess, infarction, testicular cancer, TB, or fungal epididymitis 1
• Sex partners within 60 days of symptom onset require evaluation and treatment 1

Other Important Differential Diagnoses

Torsion of Testicular Appendage

• Most common cause of testicular pain in prepubertal boys 2
• "Blue dot sign" is pathognomonic but only present in 21% of cases 2
• Ultrasound shows normal testicular perfusion with small avascular appendage 1

Segmental Testicular Infarction

• Uncommon in adults (median age 37-38 years) 1
• Classic wedge-shaped avascular area on ultrasound 2
• MRI helpful if ultrasound equivocal 1

Acute Idiopathic Scrotal Edema

• Rare, self-limiting, usually painless 1, 2
• Marked scrotal wall thickening with heterogeneous striated appearance on ultrasound 1
• Testes and epididymis appear normal with no increased vascularity 1
• Diagnosis of exclusion 2

Varicocele

• Dull, aching, or throbbing pain (rarely acute/sharp) 4
• Palpable "bag of worms" on physical examination
• Conservative management first; varicocelectomy resolves pain in 80% of carefully selected cases 4

Rare but Critical: Perforated Appendicitis

• Extremely rare presentation via patent processus vaginalis 5
• Consider if vague lower abdominal pain, vomiting, diarrhea, fever, and elevated inflammatory markers present 5
• Requires both appendectomy and scrotal drainage 5

Imaging Algorithm

Duplex Doppler ultrasound is the first-line imaging modality for all acute testicular pain 1, 2:

• Grayscale examination for testicular homogeneity and "whirlpool sign"
• Color Doppler for testicular perfusion assessment (96-100% sensitivity for torsion)
• Power Doppler more sensitive for slow flow, especially in prepubertal testes 1
• Use contralateral asymptomatic testicle as internal control 2

MRI with dynamic contrast enhancement is reserved for equivocal ultrasound cases, showing decreased/absent perfusion in torsion with high sensitivity 1

Key Clinical Pitfalls to Avoid

• Never delay urological consultation if torsion suspected clinically, even with normal imaging 2
• Normal urinalysis does not exclude either torsion or epididymitis 2
• Significant overlap exists in clinical presentations between different causes 2
• Intermittent torsion can present with recurrent brief episodes of pain (1-5 minutes) with transverse testicular orientation 6
• Always consider bilateral pathology or contralateral prophylactic fixation in torsion cases 6