Serum antibody response to pneumococcal otitis media.

Abstract

Total and immunoglobulin class-specific antibody responses to the infecting pneumococcal serotype/group in sera of 114 children, 3 months to 7 years old, who had acute pneumococcal otitis media, were measured by radioimmunoassay and enzyme-linked immunosorbent assay. Of these children 36% showed a twofold or greater increase of antibodies as a response to their infection, but the responsiveness varied from 17 to 83% among different pneumococcal types. The number and intensity of responses increased with the age of the children. In acute sera only IgG and IgM class antibodies were usually detectable. IgG and IgM class antibodies were regularly formed as a response to the infection. IgA class antibodies were frequently seen in the convalescent sera when the total antibody response was strong, and they were the first to start declining.