How do you differentiate between epididymitis and varicocele on a physical exam?

Differentiating Epididymitis from Varicocele on Physical Examination

Epididymitis and varicocele have distinctly different physical examination findings: epididymitis presents with unilateral testicular pain, a swollen and tender epididymis with the testis in normal anatomic position, while varicocele presents as a painless "bag of worms" mass in the scrotum that increases with Valsalva and decreases when supine.

Key Physical Examination Findings

Epididymitis

• Gradual onset of posterior scrotal pain that may be accompanied by urinary symptoms such as dysuria and urinary frequency 1
• Unilateral testicular pain and tenderness with the epididymis palpably swollen 2, 3
• Hydrocele and palpable swelling of the epididymis are usually present 2, 3
• Testis remains in anatomically normal position (not high-riding), which helps distinguish it from testicular torsion 1
• Positive Prehn sign (pain relief with testicular elevation) may be present, though this is not consistently reliable 4
• Fever may be present in more severe cases 2

Varicocele

• Painless palpable mass described as a "bag of worms" sensation in the scrotum, typically on the left side 5, 6
• Increases in size with Valsalva maneuver or standing position 6, 7
• Decreases or disappears when patient is supine, as venous drainage improves with position change 6, 7
• No acute tenderness unless complicated by thrombosis or associated pathology 5
• Abnormal dilation of the pampiniform plexus of veins within the scrotum that can be easily diagnosed by physical examination when clinically significant 5, 6

Critical Distinguishing Features

Pain Characteristics

• Epididymitis: Acute to subacute onset of pain over hours to days, often with associated urinary symptoms 4, 1
• Varicocele: Typically painless; when painful, presents as dull aching discomfort rather than acute pain 5

Palpation Findings

• Epididymitis: Firm, tender, swollen epididymis posterior to the testis; testis itself may be normal or involved (epididymo-orchitis occurs in up to 20% of cases) 8
• Varicocele: Soft, compressible, tortuous veins superior and posterior to the testis; testis may be smaller on affected side with chronic varicocele 5, 7

Associated Findings

• Epididymitis: Often accompanied by urethritis (which is frequently asymptomatic), urethral discharge may be present in sexually transmitted cases 2, 3
• Varicocele: May be associated with testicular hypotrophy in long-standing cases 6

Age-Based Considerations

Younger Men (<35 years)

• Epididymitis in this age group is most often caused by C. trachomatis or N. gonorrhoeae, and sexually transmitted epididymitis is usually accompanied by urethritis 2, 3
• Varicocele is highly prevalent in this age group and can be easily diagnosed by physical examination when clinically significant 5, 6

Older Men (>35 years)

• Epididymitis occurs more frequently and is associated with urinary tract infections caused by Gram-negative enteric organisms, often related to bladder outlet obstruction, recent urinary tract instrumentation, or anatomical abnormalities 2, 3, 1
• Varicocele remains a common finding but is less likely to be the cause of acute symptoms 5

Common Pitfalls to Avoid

• Do not confuse epididymitis with testicular torsion: Torsion presents with sudden severe pain, high-riding testis, absent cremasteric reflex, and negative Prehn sign (pain NOT relieved by elevation) 4, 8
• Subclinical varicoceles may not be palpable on physical examination and require ultrasound for detection 6, 7
• Chronic epididymitis may present with less dramatic findings and can coexist with varicocele, complicating the clinical picture 9
• Always consider testicular torsion first in any acute scrotal pain presentation, as it is a surgical emergency requiring intervention within 6-8 hours 4, 8

When to Use Imaging

• Epididymitis: Doppler ultrasound shows enlarged epididymis with increased blood flow (hyperemia), scrotal wall thickening, and possible hydrocele 8
• Varicocele: Ultrasound with Valsalva maneuver demonstrates venous dilation >3mm and flow reversal in the pampiniform plexus 7
• Urgent imaging is indicated when testicular torsion cannot be excluded clinically, as physical examination alone has limitations 4, 8