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Inflammatory mediators in chronic otitis media with effusion
D P Skoner1, P K Stillwagon, M L Casselbrandt
1Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine.
Insights
Inflammatory mediators like histamine are significantly higher in middle ear effusions (MEE) of children with otitis media with effusion (OME) compared to their plasma. These elevated levels suggest a role in the development of OME.
Area of Science:
- Pediatric Otolaryngology
- Inflammatory Mediators
- Middle Ear Disease
Background:
- Otitis media with effusion (OME) is a prevalent inflammatory condition in children.
- Understanding the inflammatory processes involved in OME pathogenesis is crucial for effective treatment.
Purpose of the Study:
- To quantify and compare the concentrations of histamine, prostaglandin F2 alpha metabolite, and neutrophil chemotactic factor in middle ear effusions (MEE) and plasma of children with OME.
- To investigate the relationship between mediator levels and effusion characteristics or pathogens.
Main Methods:
- Analysis of MEE and plasma samples from 102 children with persistent OME undergoing tympanostomy tube insertion.
- Assay of histamine (radioisotopic), prostaglandin F2 alpha metabolite (radioimmunoassay), and neutrophil chemotactic factor (modified Boyden chamber).
Main Results:
- Significantly higher concentrations of all three mediators were found in MEE compared to corresponding plasma.
- Histamine levels were highest in mucoid effusions and in effusions positive for Haemophilus influenzae.
- Elevated mediator levels in MEE suggest a role in OME pathogenesis.
Conclusions:
- The study demonstrates markedly elevated inflammatory mediator concentrations in the middle ear effusions of children with OME.
- These findings support the hypothesis that these mediators contribute to the inflammatory process and pathogenesis of OME.
Abstract:
Otitis media with effusion (OME) is a common middle ear inflammatory disease in the pediatric population. This article determines concentrations of three functionally and metabolically distinct inflammatory mediators in middle ear effusions (MEE) and corresponding plasma of children with OME. One hundred two patients (mean age, 4.9 years) with persistent OME were studied. Middle ear effusions were collected from all subjects and plasma from a subset at the time of tympanostomy tube insertion. Histamine was assayed radioisotopically, 13,14-dihydro-15-keto-prostaglandin F2 alpha (stable PGF2 alpha metabolite) by radioimmunoassay, and neutrophil chemotactic factor of anaphylaxis by modified Boyden chamber. Mean MEE levels of the mediators (39 +/- 13 ng/mL, 462 +/- 179 pg/mL, and 264% +/- 57% positive control, respectively) were markedly higher than those of corresponding plasma (0.5 +/- 0.1 ng/mL, 285 +/- 127 pg/mL, and 47% +/- 5% positive control, respectively). The mean histamine content of mucoid effusions (43.2 +/- 56.9 ng/mL) was significantly higher than that of purulent (22.5 +/- 10.5 ng/mL) and serous (17.9 +/- 16.8 ng/mL) effusions. Higher histamine levels were observed in effusions positive for Haemophilus influenzae when compared with those with other pathogenic isolates. The high concentrations of these mediators in MEE and their potential for inducing or sustaining the inflammatory process supports a role in the pathogenesis of OME.