The role of bacterial adherence in otitis media with effusion.

Adherence of nontypable Haemophilus influenzae and Streptococcus pneumoniae to nasopharyngeal epithelial cells was investigated in vitro. Both strains had higher affinity to the epithelial cells of children than to those of adults. In children, the adherence was significantly greater in patients with otitis media with effusion than in normal subjects. Secretory IgA in nasopharyngeal secretions was found to have antibody activity against the bacteria. Adherence of both bacteria was significantly smaller in the group having secretory IgA antibody activity than in the group having no activity. These results suggest that bacterial adherence to the nasopharynx may play an important role in the pathogenesis of otitis media with effusion in children, and that secretory IgA in nasopharyngeal secretions may be related to the decrease of adherence.