Secretory otitis media: Immunologic studies of middle ear secretions

Thirty-one middle ear effusions obtained from children with typical serous otitis media were analyzed for immunoglobulin and secretory piece content. All specimens contained IgG and almost all contained IgA and IgM. IgE was found in 2 aspirates and secretory piece in 19. The secretory piece in middle ear effusions appeared to be immunologically identical with that present in other external secretions. It was also bound to IgA protein. IgG IgA ratios of paired serum and secretions revealed considerable variations. Immunofluorescent studies of middle ear mucosa showed the presence of IgG, IgA, and IgM, and secretory piece. These studies indicate that the effusion in secretory otitis media is due at least in part to a locally active secretory process with local immunoglobulin production.