What is the best course of action for a 3-year-old male (YOM) with penis swelling and pain, especially with pain upon palpation, but no pain with voiding?

Immediate Evaluation for Testicular Torsion

This 3-year-old requires immediate urological consultation and urgent Doppler ultrasound to rule out testicular torsion, as this is a surgical emergency that can result in testicular loss if not treated within 6-8 hours of symptom onset. 1

Critical Differential Diagnosis by Age

In a 3-year-old boy with acute penile/scrotal pain and swelling, the three most urgent conditions to consider are:

• Torsion of testicular appendage: Most common cause of testicular pain in prepubertal boys like this patient 1, 2
• Testicular torsion: Surgical emergency with bimodal distribution including neonates and postpubertal boys, though can occur at any age 1, 2
• Epididymitis/epididymo-orchitis: Less common in this age group but still possible 1

Immediate Clinical Assessment

Key Physical Examination Findings to Assess:

• Location of pain and swelling: Determine if this involves the testicle itself versus isolated penile shaft 1
• Testicular position and consistency: Torsion presents with firm, tender testicle; appendage torsion may show "blue dot sign" (visible in only 21% of cases) 1, 2
• Cremasteric reflex: Absent in testicular torsion 1
• Prehn sign: Pain relief with testicular elevation suggests epididymitis; no relief (negative Prehn sign) suggests torsion 1, 2

Critical History Elements:

• Onset timing: Abrupt onset suggests torsion; gradual onset suggests infection 1, 2
• Duration of symptoms: Since symptoms started around 1900 (7 PM), calculate exact time elapsed—every hour matters 1
• Trauma history: Can be misleading as trauma may coincide with torsion; progressive worsening pain with firm, tender testicle suggests torsion rather than simple injury 2

Diagnostic Imaging

Urgent Duplex Doppler ultrasound of the scrotum is the first-line imaging modality and should be performed immediately 3, 1, 2:

• Grayscale examination: Assess for "whirlpool sign" of twisted spermatic cord (96% sensitivity) 1
• Color Doppler assessment: Evaluate testicular perfusion (96-100% sensitivity); decreased or absent blood flow indicates torsion 1
• Power Doppler: Particularly useful in prepubertal testes with slow flow 1
• Contralateral testicle: Use as internal control during evaluation 1

Ultrasound Findings by Diagnosis:

• Testicular torsion: Decreased/absent blood flow, enlarged heterogeneous testis, "whirlpool sign," ipsilateral hydrocele 1
• Appendage torsion: Normal testicular blood flow, small avascular appendage 1
• Epididymitis: Enlarged epididymis with increased blood flow 2

Critical Management Algorithm

If Testicular Torsion Suspected Clinically:

Do NOT delay surgical consultation for imaging if clinical suspicion is high—this risks testicular loss 2:

1. Immediate urological consultation regardless of imaging availability 1, 2
2. Surgical exploration and detorsion within 6-8 hours of symptom onset to prevent permanent ischemic damage 1
3. Testicular viability may be compromised after 6-8 hours; surgical outcomes are better when surgery occurs within 12 hours 1

If Appendage Torsion Confirmed:

• Conservative management with analgesics and scrotal support 1
• Self-limiting condition that does not require surgery 1

If Epididymitis Confirmed:

• Appropriate antibiotics based on age and likely pathogens 2
• Scrotal elevation and analgesics 1

Common Pitfalls to Avoid

• Assuming trauma history excludes torsion: Trauma can be coincidental; progressive worsening pain points to torsion 2
• Waiting for imaging when clinical suspicion is high: Delaying surgical consultation risks testicular loss 2
• Starting antibiotics empirically: This delays correct diagnosis if torsion is present 2
• Relying solely on normal urinalysis: Normal urinalysis does not exclude testicular torsion 1
• False-negative Doppler: Can occur with partial torsion or spontaneous detorsion; clinical judgment remains paramount 1

Additional Considerations for Isolated Penile Swelling:

If examination confirms swelling is truly isolated to penile shaft without testicular involvement, consider:

• Penile cellulitis: Requires antibiotics; Group B streptococci are usual organisms 4
• Penile trauma/hematoma: May require surgical evaluation if severe 5, 6
• Smegma retention cyst: Benign finding in young boys from physiologic foreskin separation 7

However, given the pain with palpation and acute onset, testicular pathology must be definitively excluded first 1, 2.