What is the appropriate workup for a patient presenting with testicular pain?

Workup for Testicular Pain

The appropriate workup for testicular pain should begin with Duplex Doppler ultrasound of the scrotum, which is the imaging modality of choice for evaluating acute scrotal pain as it can rapidly diagnose testicular torsion and other etiologies with high sensitivity and specificity. 1, 2

Initial Assessment

• Determine timing and onset of pain - testicular torsion typically presents with abrupt scrotal pain, while epididymitis has a more gradual pain onset 2
• Assess for high-risk features of testicular torsion:
  • Sudden onset of severe unilateral pain 3
  • Testicular swelling (2 points in TWIST score) 4
  • Hard testis (2 points in TWIST score) 4
  • Absent cremasteric reflex (1 point in TWIST score) 4
  • Nausea/vomiting (1 point in TWIST score) 4
  • High riding testis (1 point in TWIST score) 4
• Note that testicular torsion can occasionally present with minimal pain, which can lead to diagnostic delays 5, 6
• Consider age of patient - torsion has a bimodal distribution with peaks in neonates and postpubertal boys, while epididymitis is more common in adults over 25 years 2, 3

Diagnostic Algorithm

High Clinical Suspicion for Testicular Torsion (TWIST score ≥6)

• Immediate urological consultation without delay for imaging 3, 4
• Surgical exploration is indicated as testicular viability may be compromised if not treated within 6-8 hours of symptom onset 3, 7

Intermediate Clinical Suspicion (TWIST score 1-5)

• Urgent Duplex Doppler ultrasound of the scrotum 2, 4
• Ultrasound should include:
  • Grayscale examination to assess testicular homogeneity and identify "whirlpool sign" of twisted spermatic cord (96% sensitivity) 2
  • Color Doppler assessment of testicular perfusion (96-100% sensitivity) 2
  • Power Doppler (especially useful for prepubertal testes with slow flow) 2

Low Clinical Suspicion (TWIST score 0)

• Duplex Doppler ultrasound to evaluate for other causes of testicular pain 2, 4
• Consider urinalysis to evaluate for epididymitis, though normal urinalysis does not exclude this diagnosis 2

Differential Diagnosis to Consider

• Testicular torsion - surgical emergency requiring intervention within 6-8 hours 1, 3
• Epididymitis/epididymo-orchitis - most common cause in adults 2
• Torsion of testicular appendage - most common cause in prepubertal boys 1, 2
• Other causes: hydrocele, varicocele, tumor, trauma, inguinal hernia 1, 7
• Chronic orchialgia (pain >3 months) - may require specialized evaluation 8

Important Caveats

• Do not delay urological consultation if testicular torsion is suspected, even if ultrasound is pending 3, 7
• A normal ultrasound examination cannot completely exclude the diagnosis of testicular torsion 7
• The "blue dot sign" is pathognomonic for appendage torsion but is only seen in 21% of cases 1
• Patients with high TWIST scores (≥6) have a positive predictive value of 93.5% for testicular torsion and may proceed directly to surgery without imaging 4
• Patients with low TWIST scores (0) have a negative predictive value of 100% for ruling out torsion 4