A usually painless scrotal swelling, called a varicocele, is a collection of abnormally enlarged spermatic cord veins most commonly found on routine examination of asymptomatic boys ages 10 to 15 years Most varicoceles occur on the left, representing spermatic vein incompetence caused by the left spermatic vein draining into the renal vein at a sharp angle, whereas the right spermatic vein drains into the inferior vena cava On occasion, a varicocele can present with mild pain or discomfort The hemiscrotum appears full but overlying skin is normal The testis and epididymis should be palpated to be normal A mass of varicose veins described as “a bag of worms” can be appreciated above the testicle, which is more prominent when examined while standing Doppler ultrasound demonstrates both normal flow to the testis and the collection of tortuous veins Most varicoceles are asymptomatic and benign and just observed Patients determined to have a varicocele, especially when they present with discomfort, should be referred for urologic follow-up Some large varicoceles may require internal spermatic vein ligation or testicular vein embolization and may effect testicular size and fertility Inferior vena cava obstruction should be considered when the patient is prepubertal or if the varicocele is acute in onset, right sided, or remains unchanged in the supine position Spermatocele Located above and posterior to the testicle in postpubertal boys, spermatoceles are sperm-containing cysts of the rete testes, ductuli efferentes, or epididymis Multiple and bilateral spermatoceles may occur On examination a small, nontender mass that transilluminates may be appreciated distinct from and posterior to the testicle These masses must be differentiated from a hydrocele or tumor Sonography may confirm the location and help distinguish a spermatocele from tumor Referral to a urologist is indicated for the excision of large uncomfortable spermatoceles or for aspiration to differentiate a hydrocele from a spermatocele Otherwise, no specific treatment is needed (see Chapter 119 Genitourinary Emergencies ) Idiopathic Scrotal Edema Idiopathic scrotal edema is a rare entity that represents only 2% to 5% of acute scrotal swellings in otherwise normal children Typically, a prepubertal child presents with the rapid onset of painless edema of the scrotal wall that may be bilateral and may extend up onto the abdomen The skin of the scrotum may be erythematous The child is usually afebrile, and urinalysis is negative Through the edematous scrotum, the testes can be felt to be normal in size and nontender