Effect of formalin-fixed hemophilus influenzae and streptococcus pneumoniae on dye transport by the Chinchilla eustachian tube

An in situ method for measuring the ability of the middle ear and eustachian tube ciliated epithelium to transport dye to the nasopharynx was used to assess the role endotoxin-containing killed bacteria have on the development of otitis media with effusion. In addition, electron microscopy was used to monitor histological changes induced by exposure to these organisms and the ability of the mucosa to recover. The results indicated that exposure to a killed gram-negative but not a gram-positive otitis media pathogen leads to early production of middle ear fluid, evidence of capillary leakage and significant slowing of mucociliary transport. The damage was, however, reversible with the epithelium returning to normal both functionally and histologically within 7 days of exposure.