What is the appropriate history, physical examination, and initial workup for a man presenting with acute testicular pain?

Evaluation of Acute Testicular Pain

Any man presenting with acute testicular pain must be evaluated immediately as a potential surgical emergency until testicular torsion is definitively excluded, as testicular viability is compromised if surgical intervention does not occur within 6-8 hours of symptom onset. 1

Critical History Elements

Timing and onset of pain:

• Abrupt, severe onset strongly suggests testicular torsion 1
• Gradual onset over hours to days more consistent with epididymitis 1
• Document exact time of pain onset, as this determines the critical window for intervention 1

Associated symptoms:

• Nausea and vomiting are common with torsion 2, 3
• Previous similar episodes occur in up to 50% of torsion cases 4
• Dysuria, urethral discharge, or fever suggest infectious etiology 1

Age-specific considerations:

• Torsion has bimodal distribution: neonates and postpubertal boys (peak incidence) 1, 5
• Torsion is rare over age 35 1
• Epididymitis is the most common cause in adults over 25 (approximately 600,000 cases annually in the US) 1
• Torsion of testicular appendage is most common in prepubertal boys 1

Physical Examination Findings

Key distinguishing features for torsion:

• Absent cremasteric reflex is the most accurate sign of testicular torsion 6
• High-riding testicle with abnormal lie 4, 3
• Testicular retraction strongly associated with torsion 7
• Firm, swollen, exquisitely tender testicle 4
• Negative Prehn sign (pain NOT relieved by testicular elevation) 1
• Red, swollen scrotum; markedly enlarged scrotum with bluish hue indicates vascular compromise and possible hemorrhagic necrosis 1, 2

Features suggesting epididymitis:

• Positive Prehn sign (pain relieved by elevation) 1
• Gradual onset of tenderness 1
• Palpable, tender, enlarged epididymis 1
• Scrotal wall erythema and warmth 1

Special findings:

• "Blue dot sign" (tender nodule with blue discoloration on upper pole) is pathognomonic for appendage torsion, but only present in 21% of cases 1, 6

Initial Workup

Laboratory studies:

• Urinalysis with microscopy 1
• Normal urinalysis does NOT exclude testicular torsion 1
• Abnormal urinalysis may suggest epididymitis but normal results do not exclude it 1
• Consider urethral swab for gonorrhea/chlamydia if sexually active and infectious etiology suspected 1

Imaging - Duplex Doppler Ultrasound:

When to order imaging:

• If clinical suspicion for torsion is HIGH (based on absent cremasteric reflex, high-riding testis, abrupt severe pain), proceed IMMEDIATELY to surgical exploration without imaging 3
• For intermediate clinical suspicion, urgent Duplex Doppler ultrasound is indicated 1
• Never delay surgical exploration to obtain imaging when clinical suspicion is high 3

Ultrasound protocol must include: 1

• Grayscale examination assessing testicular size, homogeneity, and the "whirlpool sign" of twisted spermatic cord (96% sensitivity) 1, 8
• Color Doppler comparing blood flow to contralateral testis (sensitivity 96-100%) 1, 8
• Power Doppler (particularly useful in prepubertal boys with normally reduced flow) 1, 8
• Spectral Doppler analysis of upper, mid, and lower poles 1
• Always use contralateral asymptomatic testicle as internal control 1

Ultrasound findings in torsion: 1

• Decreased or absent testicular blood flow compared to contralateral side
• "Whirlpool sign" (most specific finding) 1, 5
• Enlarged heterogeneous testis appearing hypoechoic
• Ipsilateral hydrocele
• Scrotal skin thickening

Ultrasound findings in epididymitis: 1

• Enlarged epididymis with INCREASED blood flow on color Doppler
• Scrotal wall thickening
• Hydrocele
• Up to 20% have concomitant orchitis

Critical Diagnostic Pitfalls

Ultrasound limitations:

• Sensitivity ranges from 69-96.8%, meaning false-negative evaluations occur in up to 30% of cases 1, 8
• Partial torsion (<450 degrees) may show persistent arterial flow because venous obstruction occurs first 1
• Spontaneous detorsion can cause false-negative results 1
• Prepubertal boys normally have reduced intratesticular flow, potentially causing false-positive results 1, 8
• When clinical suspicion remains high despite normal Doppler, proceed immediately to surgical exploration 1

Clinical overlap:

• Significant overlap exists in presentation between different causes of acute scrotal pain 1
• Do not rely solely on imaging when clinical findings strongly suggest torsion 3

Management Algorithm Based on Clinical Suspicion

HIGH clinical suspicion (absent cremasteric reflex + high-riding testis + abrupt severe pain):

• Immediate urological consultation and surgical exploration WITHOUT imaging 1, 3
• Do not delay for ultrasound 3

INTERMEDIATE suspicion:

• Urgent Duplex Doppler ultrasound 1
• If ultrasound confirms torsion: immediate surgical exploration 1
• If ultrasound equivocal but clinical suspicion persists: proceed to surgical exploration 1

LOW suspicion with imaging confirming alternative diagnosis (epididymitis):

• Bed rest, scrotal elevation, analgesics 1
• Appropriate antibiotics based on age and risk factors 1

Time-critical nature:

• Surgical detorsion must occur within 6-8 hours of symptom onset to prevent permanent ischemic damage 1, 5, 3, 6
• Testicular salvage rates decline significantly after 6 hours 3, 6
• Maximum window is 12 hours, but outcomes are significantly worse 8