Skin rash in a 2-week-old infant.

We presented a case of a male infant with annular patchy rash on his torso since 2 weeks of age. This was initially diagnosed as tinea corporis but did not respond to oral antifungal treatment. Because of the appearance of the rash and a history of a certain disease in a maternal aunt, we suspected the most probable cause of the rash and the diagnosis was confirmed by laboratory testing. Furthermore, laboratory screening of the mother, who was asymptomatic, revealed that she was seropositive for the disease and was counseled on the importance of follow-up. The infant's rash gradually improved and completely disappeared, without any sequalae by 8 months of age.