Reproductive · Male Infertility
The facts most likely to be tested
A varicocele is a dilation of the pampiniform plexus of spermatic veins caused by incompetent valves.
The left testicular vein is most commonly affected because it drains into the left renal vein at a perpendicular angle, increasing hydrostatic pressure.
Physical examination classically reveals a bag of worms sensation in the scrotum that increases with standing or Valsalva maneuver.
A varicocele that fails to decompress when the patient is in the supine position suggests venous obstruction (e.g., renal cell carcinoma or thrombus).
Varicoceles are the most common surgically correctable cause of male infertility due to hyperthermia of the testes.
The gold standard for diagnosis in ambiguous cases is scrotal ultrasound with Doppler, which demonstrates retrograde venous flow.
Initial management for asymptomatic patients is observation, while surgical varicocelectomy or percutaneous embolization is indicated for infertility or testicular atrophy.
Vignette unlocked
A 28-year-old male presents to the clinic for evaluation of infertility after 18 months of unprotected intercourse. On physical examination, the patient has a soft, irregular mass in the left hemiscrotum that feels like a bag of worms. The mass increases in size with Valsalva maneuver and decreases when the patient is supine. Scrotal ultrasound confirms the presence of dilated pampiniform plexus veins with retrograde flow.
What is the most likely pathophysiology underlying this patient's condition?
Incompetent valves in the left testicular vein
The vignette describes a classic varicocele, which is caused by incompetent valves in the pampiniform plexus, most commonly on the left side due to its anatomical drainage into the left renal vein.
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Etiology / Epidemiology
Dilation of the pampiniform plexus; most common cause of male infertility.
Clinical Manifestations
Bag of worms sensation that decreases when supine.
Diagnosis
Scrotal ultrasound is the gold standard; venous diameter >2 mm.
Treatment
Observation for asymptomatic; surgical ligation for infertility or pain.
Prognosis
High association with testicular atrophy and impaired semen parameters.
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Epidemiology & Etiology
Most common in men aged 15–25. Occurs predominantly on the left side due to the perpendicular insertion of the left spermatic vein into the left renal vein. Right-sided varicoceles are rare and warrant investigation for retroperitoneal malignancy.
Pertinent Anatomy
The pampiniform plexus is a network of small veins in the spermatic cord. The left internal spermatic vein drains into the left renal vein, while the right drains directly into the inferior vena cava.
Pathophysiology
Incompetent venous valves lead to retrograde blood flow and venous stasis. This causes local hyperthermia and hypoxia within the testis. Chronic heat stress disrupts spermatogenesis, leading to infertility and potential Leydig cell dysfunction.
Clinical Manifestations
Patients present with a dull, aching scrotal pain or a palpable bag of worms mass. The mass is pathognomonic for increasing in size with the Valsalva maneuver and decreasing when supine. Sudden onset or failure to decompress when supine suggests a mass effect obstructing the renal vein.
Diagnosis
The scrotal ultrasound is the diagnostic test of choice. A venous diameter >2 mm during the Valsalva maneuver confirms the diagnosis. Physical exam should be performed in both standing and supine positions.
Treatment
Asymptomatic patients require only observation. Surgical ligation (varicocelectomy) is indicated for infertility, testicular atrophy, or persistent pain. Embolization is an alternative, but surgical ligation remains the standard for fertility improvement.
Prognosis
Varicoceles are progressive and associated with testicular atrophy in adolescents. Post-surgical improvement in semen parameters is seen in 50-70% of patients. Annual monitoring of testicular size is required in pediatric populations.
Differential Diagnosis
Hydrocele: transilluminates with light
Spermatocele: painless, fluid-filled cyst at the epididymal head
Inguinal hernia: bowel sounds may be auscultated
Testicular tumor: firm, non-tender, does not decompress
Epididymitis: acute pain, fever, and dysuria