Endotoxin and Tumor Necrosis Factor-α in Middle Ear Effusions in Relation to Upper Airway Infection

Objectives/Hypothesis: This study was performed to elucidate the role of endotoxin and tumor necrosis factor‐α (TNF‐α) in the middle ear effusions (MEEs) of children with otitis media with effusion (OME) in relation to the chronicity of the disease and the presence of upper respiratory tract infection (URTI). Study Design: In a retrospective study 140 MEEs were collected from 101 children between 2 and 12 years of age, and evaluated for the cytokine TNF‐α and the lipopolysaccharide endotoxin. The amounts were quantified and correlated with the type of MEE, OME duration, and the presence of URTI. Methods: Endotoxin levels were measured using a limulus amebocyte lysate assay and TNF‐α levels were measured with an enzyme‐linked immunosorbent assay (ELISA). Means of the different variables were compared using the one‐way ANOVA least significance difference test with P < .05 Results: In MEEs classified as mucopurulent (22.8%) both endotoxin and TNF‐α levels (11.9 ± 3 ng/mg total protein and 61.1 ± 21 pg/mg total protein, respectively) were significantly higher compared with serous‐ (23.6%) or mucoid‐ (53.6%) type effusions. Fifty‐five percent of the children who were classified as having chronic OME also had significantly higher amounts of endotoxin and TNF‐α. The majority of the children (61%) had no URTI, although children with URTI (36%) did also have significantly higher levels of endotoxin and TNF‐α in their middle ears. Conclusions: These results indicate that there is a strong correlation between the endotoxin and the TNF‐α concentration in the middle ear and the type of MEE, the presence of URTI, and the chronicity of the disease.