Atypical measles syndrome: pathologic and serologic findings.

The clinical course of measles occurring in 17 adolescents who had previously received killed measles vaccine is described. All adolescents had a peripheral dermatitis. Fifteen had characteristic pulmonary infiltrates. Serologic study in six adolescents using immunoprecipitation of 35S-methionine-labeled measles virus antigens revealed that 5/6 acute sera lacked antibody to the hemolysin antigen whereas 5/6 sera contained antibody to hemagglutinin antigen. Skin biopsies, obtained from three patients, demonstrate a combination of an Arthus reaction and delayed hypersensitivity. The typical measles histologic complex was absent. Measles virions were seen in the deep dermal blood vessels. The serologic and histopathologic presentation of this disease indicates that killed vaccine does not adequately induce antibody to the hemolysin (F) which is necessary to prevent cell-to-cell spread of paramyxoviruses. Killed vaccine does, however, produce hemagglutinin antibody and simultaneously incites later hypersensitivity to wild virus infection, producing the unusual dermatopathologic reaction seen.