What is the recommended treatment for scrotal pain with a negative ultrasound?

Management of Scrotal Pain with Negative Ultrasound

When ultrasound is negative in a patient with scrotal pain, the management depends critically on clinical suspicion for testicular torsion and the specific clinical presentation—if torsion remains suspected despite negative imaging, immediate surgical exploration is mandatory, while other etiologies can be managed conservatively with close follow-up. 1, 2

Understanding the Diagnostic Limitations

The negative ultrasound does not definitively exclude testicular torsion, which is the most critical consideration:

• Color Doppler ultrasound has imperfect sensitivity (69-96.8%) and can miss up to 30% of cases, particularly with partial torsion or spontaneous detorsion 1, 2
• False-negative evaluations occur most commonly with partial torsion where arterial flow persists because venous obstruction occurs first, and in early presentations within the first few hours when the testis may appear normal 1, 2
• The presence of blood flow on Doppler does not exclude torsion—reperfusion after early ischemia from torsion/detorsion can create reactive hyperemia that mimics epididymitis 1

Clinical Decision Algorithm

High Clinical Suspicion for Torsion (Despite Negative Ultrasound)

Proceed immediately to surgical exploration without delay 2:

• Abrupt onset of severe scrotal pain 2
• Young patient (adolescent or young adult with bimodal peak in neonates and postpubertal boys) 2
• History of similar episodes that spontaneously resolved (suggesting intermittent torsion) 3
• Negative Prehn sign (pain not relieved with testicular elevation) 2
• Normal urinalysis (does not exclude torsion) 2

Surgical exploration must occur within 6-8 hours of symptom onset to prevent permanent ischemic damage and testicular loss 2

Low Clinical Suspicion with Negative Ultrasound

Consider alternative diagnoses and manage accordingly:

Mild Epididymitis

• This is an underrecognized cause of scrotal pain with normal imaging 4
• Characterized by mild to moderate epididymal tenderness without epididymal enlargement on examination or ultrasound 4
• Treat empirically with oral antibiotics, activity restriction, scrotal elevation, and analgesics 4
• All patients in one series fully recovered with this approach 4

Segmental Testicular Infarction

• May not be apparent on initial ultrasound and requires repeat imaging if pain persists 5
• Classic finding is wedge-shaped avascular area, though can present as round lesions with variable Doppler flow 2
• Management is typically conservative, though some require surgical intervention 5
• Consider MRI if ultrasound findings are equivocal 6

Acute Idiopathic Scrotal Edema

• Rare, self-limiting condition primarily affecting prepubertal boys but can occur in adults 2
• Usually painless or minimally painful with marked scrotal wall thickening 2
• Diagnosis of exclusion 2

Age-Specific Considerations

Adults over 35 years:

• Testicular torsion is rare in this age group 2, 6
• Epididymitis is overwhelmingly the most common cause (approximately 600,000 cases annually in the US) 2
• Gradual onset pain with possible abnormal urinalysis supports epididymitis 2

Adolescents and young adults:

• Testicular torsion remains a critical consideration even with negative imaging 2
• Epididymitis is still common in this age group 2
• Lower threshold for surgical exploration given higher torsion risk 2

Critical Pitfalls to Avoid

• Never rely solely on imaging when clinical suspicion for torsion is high—ultrasound sensitivity is imperfect and surgical outcomes depend on rapid intervention 1, 2
• Do not assume normal urinalysis excludes torsion 2
• Recognize that fever, waxing and waning pain, and laboratory markers for infection help distinguish epididymitis from torsion/detorsion with reactive hyperemia 1
• Consider repeat ultrasound if pain persists and initial imaging was negative, as segmental infarction may not be apparent initially 5

Follow-Up Strategy

For patients managed conservatively with negative ultrasound:

• Close clinical follow-up within 24-48 hours to reassess symptoms 5
• Clear return precautions for worsening pain, which should prompt immediate re-evaluation 5
• Consider repeat imaging if symptoms persist or worsen 5
• Empiric antibiotic trial for suspected mild epididymitis with activity restriction and supportive measures 4