Sir.—Kawasaki disease (KD) is an acute febrile mucocutaneous vasculitis of unknown cause occurring in infants and children.1 Diagnostic criteria for KD have been defined by the Centers for Disease Control2 and are shown in Table 1. In the last decade, cases of atypical KD (AKD) have been reported that do not meet these criteria, but that have a very high coronary artery complication rate and mortality.3-13 These coronary complications can safely be pre
vented with intravenous immunoglobulin if administered within 10 days of the beginning of illness.14-16 In AKD, diagnosis is often delayed, preventing this effective early therapy.3-13 We report five cases of KD (the first three of which are atypical cases) with development of a hydrocele by 10 days after illness began. To our knowledge, this is the first report of hydrocele with KD, and these findings may aid in early diagnosis and