Atypical exanthema in a patient with infectious mononucleosis.

A 19-year-old male with a sore throat developed numerous, indistinct, erythematous, maculopapular lesions on the trunk. The eruptions, which mimicked secondary syphilis, continued for seven weeks and faded away without pigmentation or scarring. The laboratory examinations revealed lymphocytosis with atypical lymphocytes, seroconversion of Epstein-Barr virus titers, and elevation of transaminase in liver function.