This edema of the scrotal wall is of unknown origin, although it is believed to represent a form of angioneurotic edema Other etiologies include insect bites, allergic reactions, cellulitis, and contact dermatitis No specific therapy for idiopathic scrotal edema has been demonstrated to be effective Bed rest and scrotal elevation may help Children spontaneously begin to improve within 48 hours, regardless of treatment Cellulitis, allergic reactions, and contact dermatitis should be appropriately treated Occasionally, scrotal edema is seen secondary to diseases that cause generalized edema and/or ascites, such as nephrosis and cirrhosis Kawasaki Disease Another vasculitis that can produce scrotal swelling and mild pain is Kawasaki disease, which has characteristic features, including fever, adenopathy, rash, conjunctivitis, and irritability Although discussed in detail elsewhere (see Chapter 101 Rheumatologic Emergencies ), it is important to note the association of scrotal swelling with this systemic disease to avoid unnecessary surgical explorations or delay in diagnosis of the underlying vasculitis Testis Tumor Testicular or paratesticular tumors are rare in young children However, in young males of ages 15 to 35 years, it is the most common solid tumor and represents 20% of cancers diagnosed in males Testicular cancer usually presents as painless, unilateral, and firm to hard scrotal swellings discovered by the patient or physician on physical examination Some patients report an achy feeling, and in rapid-growing tumors associated with hemorrhage or infarction, acute scrotal pain may be reported Leukemic infiltration of the testis may present bilaterally The mass does not transilluminate, but an associated reactive hydrocele may so In children younger than years of age, the tumor usually is a yolk sac carcinoma, or teratoma, and after puberty, germinal cell tumors are seen Evaluation involves an initial testicular ultrasound examination usually followed by surgical exploration and a possible radical inguinal orchiectomy Antenatal Torsion Testis (Newborn) A newborn boy may present with a painless, smooth, testicular enlargement that is usually dark in color with minimal or no edema of the scrotum This presentation occurs in 70% of newborn cases of torsion, represents prenatal, extravaginal torsion, whereby the entire testis and the tunica vaginalis twist together around the spermatic cord The remaining cases of neonatal torsion occur postnatally during the first month of life, before fixation occurs Salvage of the