A 7-DAY-OLD infant was noted to have bluish discoloration of the scrotal, inguinal, and perineal areas, bilaterally (Figure 1). The testes were palpable, nontender, and seemed to have normal consistency. The infant was born after 40 weeks' gestation to a gravida 2, para 2 woman. He was delivered vaginally with the aid of vacuum extraction and weighed 3800 g, with Apgar scores of 9 and 10 at 1 and 5 minutes, respectively. Other than mild swelling of the scrotum noted soon after birth, findings from physical examination were unremarkable. The neonatal course was complicated by decreasing appetite and jaundice. Findings from ultrasonographic scan of the abdomen obtained on day 7 showed masses with mixed echogenic patterns above both kidneys (Figure 2). Findings from repeated ultrasonographic scan 4 days later showed cystic changes in the masses (Figure 3).