Secretory IgA and squamous epithelization in adenoids of children with otitis media with effusion

Infection of adenoids has been considered a causative factor of otitis media with effusion (OME). We believe that the deterioration in the mucosal barrier of adenoids makes the adenoids vulnerable to bacterial infections, resulting OME. In this study, we evaluated secretory IgA, secretory component (SC) and reticular and squamous changes of ciliated epithelium in adenoids. Fourteen children with OME (OME(+)) and 6 children without any history of OME (OME(+)) were enrolled in the study. Immunohistological study on the adenoids using anti-IgA and anti-SC revealed no significant difference between two groups in the number of IgA positive cells in the subepithelial layer. However, the proportion of the secretory component-positive area in the epithelium was significantly lower in the OME(+) group (11.4 +/- 13.0%) than in the OME(+) group (20.7 +/- 9.6%) (Mann Whitney U test, p <0.05). Histological study using hematoxylin and eosin staining revealed that the area of squamous epithelization was bigger in the OME(+) group (32%) than in the OME(+) group (16%) (p <0.05). The number of ciliated cells was decreased in the OME(+) group (13%) compared with the OME(+) group (31%). The epithelium was thicker in the OME(+) group (101 mu m) than in the OME(+) than in the OME(+) group (79 mu mm) (p <0.05). These results suggest that the production of the secretory component is lower in the epithelium of adenoids in children with OME. Hyperplasia, squamous epithelization and decreased number of ciliated cells may also hamper mucosal clearance of the adenoids of children with OME. These findings suggest that the adenoids of children with OME are more susceptible to infections than adenoids of children without OME.