TABLE 61.2 COMMON CAUSES OF ACUTE SCROTAL SWELLING Infancy Hydrocele Hernia Childhood Hernia Torsion of the appendix testes Torsion of the testes Trauma Adolescence Epididymitis Torsion of the appendix testes Torsion of the testes Trauma In the immediate neonatal period, prenatal torsion may cause painless scrotal enlargement In infancy, the most common causes of painless scrotal swelling ( Table 61.2 ) are hernias and hydroceles; a hernia is often reducible Beyond infancy, the physician must consider hernia, tumor, spermatocele, and varicocele when evaluating painless scrotal swelling determined to be within the scrotum Kawasaki disease, HSP, and idiopathic scrotal edema involve the scrotal sac and cause swelling that is either painless or mildly painful Painful swelling may follow a well-documented injury, in which case the likely diagnoses are hematocele, hematoma, testicular rupture, and traumatic epididymitis The physician should bear in mind that boys with testicular torsion often give a history of having had an incidental minor injury Nontraumatic scrotal pain raises the suspicion of a testicular torsion, if the testis is tender Unless the diagnosis of a systemic disorder (HSP, Kawasaki disease) is obvious, another structure such as an appendage is reliably determined to be the source of pain within the scrotum, the patient is an adolescent with the classic signs of epididymitis, or an incarcerated hernia is reduced, imaging via Doppler ultrasound is usually indicated All patients in whom torsion is suspected require a surgical consultation History