Lysozyme Levels in Middle Ear Effusion and Serum in Otitis Media

Abstract

Lysozyme concentrations in middle ear effusion and serum were determined in patients with otitis media with effusion. Lysozyme concentrations in middle ear effusion were significantly higher than in serum. Children with mucoid otitis media showed significantly higher levels of lysozyme in middle ear effusion than children with serous otitis media and adults with otitis media with effusion. Higher levels of lysozyme were observed in the group of children younger than 5 years old compared with the age group of 6- to 10-year-olds. Lysozyme concentrations of middle ear effusion in adults were significantly lower than those of mucoid otitis media in children. These results indicate that lysozyme plays an important role in the disease process of otitis media.

Compositional Difference in Middle Ear Effusion: Mucous Versus Serous

“…Middle ear mucosa, a part of airway epithelium, also produces these two components, and hypersecretion of these components is considered to be an important pathogenic factor in OME. 2–4 …”

“…Chemical analysis of middle ear effusion has shown a large quantity of mucin 2 and higher levels of serous secretions, such as lysozyme 3 and secretory immunoglobulin A (sIgA), 4 than in the serum. These results indicate that middle ear effusions are composed not only of transudate but also of an exudate that is actively secreted from the middle ear mucosa.…”

The Role of Inflammatory Mediators in the Pathogenesis of Otitis Media and Sequelae

“…There are differences in the inflammatory mediators involved in child and adult OME. Higher levels of lysozyme, a nonspecific defense lysosomal enzyme against bacterial infection, were found in the effusions of children compared to adults (179). The early response cytokines IL-1β and TNF-α were present in higher percentages of effusions from children than adults (85% of children vs. 12% of adults for IL-1β and 85% of children vs. 8% of adults for TNF-α), suggesting that adult OM is associated with lower expression of the early response cytokines (46).…”

The Role of Gastric Pepsin in the Inflammatory Cascade of Pediatric Otitis Media

“…[25][26][27][28] In addition, if infection occurs in the middle ear mucosa, the effusion undergoes a purulent phase. If eustachian tube dysfunction resolves during the acute episode, it is possible that the effusion may clear and the middle ear will become dry [29][30][31] ; however, when underlying causes are not identified, the resolution sometimes fails and the inflammation becomes chronic or recurrent otitis me-dia. We hypothesized that the presence of pepsin A in the middle ear cleft might be responsible for or aggravate middle ear inflammation, thus preventing resolution of an acute episode.…”