Serous or mucoid effusion in the course of secretory otitis media: influence of ion transport modulation

Objective: Secretory otitis media is defined by a chronic effusion in the middle ear cavities, behind an intact tympanic membrane without acute infection. In the course of secretory otitis media, the effusion is sometimes thick (or mucoid) and other times thin (or serous). For several authors, these differences might be related to different inflammatory levels rather than to distinct pathophysiological mechanisms. The purpose of this study was to determine whether the modulation of ion transport by inflammation could account for the differences observed in the aspect of ME effusion. Methods: Hydrogen peroxide (H2O2), used as an inflammation model was tested on a middle ear cell line (MESV) in culture. Results: Results show that low and high concentrations of H2O2 have opposite effects on ion (and then water) absorption by the middle ear epithelium. Conclusion: the modulation of ion and water absorption by inflammation could modify the mucins concentration in the effusion, and explain observed viscosity differences in the course of secretory otitis media.