Allergic otitis media with gelatinous mucoid fluid containing eosinophils

Eosinophilic otitis media: a new middle ear disease entity

Eosinophilic otitis media (EOM) is intractable otitis media characterized by the presence of a highly viscous yellow effusion containing eosinophils. It occurs mainly in patients with bronchial asthma and is resistant to conventional treatments for otitis media. Here we discuss the clinical features, pathogenesis, and management of EOM. EOM predominantly affects women and presents most often in patients in their 50s. The clinical features of the middle ear in EOM are roughly divided into the otitis media with effusion type and chronic otitis media type. The latter is further divided into two subtypes: simple perforation and granulation tissue formation. EOM is often complicated by rhinosinusitis (eosinophilic sinusitis). High-tone loss is more frequently found and more severe in EOM patients than in chronic otitis media control patients, and EOM patients sometimes become deaf suddenly. Systemic or topical steroid administration is the most effective treatment for patients with EOM. The instillation of triamcinolone acetonide, a suspension of steroids, into the middle ear is very effective for controlling eosinophilic inflammation. It is very important to explain to patients with EOM that the disease may last for a long period and that progressive and sudden hearing loss may occur.

Successful treatment of eosinophilic otitis media using ramatroban: Report of two cases

OBJECTIVE

The pathogenesis of eosinophilic otitis media is not yet fully understood. The purpose of this paper is to describe the clinical course of our two patients with eosinophilic otitis media and to discuss the pathogenesis and treatment of this intractable condition.

METHODS

Two cases of eosinophilic otitis media were treated with ramatroban.

RESULTS

The middle ear effusion has been well controlled in both patients for more than 1 year with minimal corticosteroid therapy.

CONCLUSIONS

Our experience suggests that the pathogenesis of eosinophilic otitis media is related to the pharmaceutical effects of ramatroban, i.e., inhibition of the thromboxane A2 receptor (TP) and the chemoattractant receptor-homologous molecule expressed on Th2 cells (CRTH2).

Eosinophil chemoattractants in the middle ear of patients with eosinophilic otitis media

BACKGROUND

Patients with intractable otitis media associated with bronchial asthma have an extensive accumulation of eosinophils in the effusion and mucosa of the middle ear; this condition is called eosinophilic otitis media (EOM). It remained to be determined how eosinophils accumulate in the middle ear.

OBJECTIVES

To clarify the pathogenesis of middle ear diseases, we measured the concentration of eosinophil chemoattractants in middle ear effusion (MEE), and carried out immunohistochemical studies of middle ear mucosa specimens to demonstrate the expression of eosinophil chemoattractants.

METHODS

Middle ear effusion samples were obtained from 15 EOM patients with bronchial asthma and from six controls for the measurement of eosinophil cationic protein (ECP), IL-5, eotaxin and regulated on activation, normal T expressed and secreted concentrations. Middle ear mucosa samples were also taken from 14 EOM patients and 16 controls for immunohistochemical study. In 10 EOM patients, the numbers of immunoreactive cells as well as apoptotic cells were determined before and after the topical application of triamcinolone acetonide into the middle ear.

RESULTS

In EOM, significantly higher ECP and IL-5 concentrations were detected in MEE than in serum, and ECP, IL-5 and eotaxin concentrations in MEE were higher in the EOM patients than in the controls. ECP concentration positively correlated with that of IL-5. Immunohistochemically, the numbers of cells positive for EG2 and ecalectin were significantly higher in the EOM patients than in the controls. After the topical application of triamcinolone acetonide, the numbers of infiltrating cells and immunoreactive cells distinctly decreased, whereas the number of apoptotic cells significantly increased.

CONCLUSION

In EOM, locally produced IL-5 may play a crucial role in the accumulation of eosinophils in the middle ear. Chemokines such as ecalectin and eotaxin are also produced in the middle ear, and help activate and enhance the survival of eosinophils to induce the intractable condition in the middle ear. The topical application of triamcinolone acetonide induces the apoptosis of not only eosinophils but also eosinophil chemoattractant-producing cells, thereby improving the middle ear condition.

IL-5 and eotaxin levels in middle ear effusion and blood from asthmatics with otitis media with effusion

OBJECTIVE

The purpose of this study was to evaluate eosinophil infiltration as well as IL-5 and eotaxin levels in middle ear effusion (MEE) and blood from otitis media with effusion (OME) patients with asthma and to compare the findings with those from OME patients without asthma (control group).

MATERIAL AND METHODS

Levels of IL-5 and eotaxin in MEE and blood were measured by means of enzyme-linked immunosorbent assay.

RESULTS

5 levels in MEE were significantly higher than those in blood in both groups of patients and in OME patients with asthma than in the control group. In addition, in OME patients with asthma, there was a significant correlation between the percentage of eosinophils and IL-5 levels in MEE. Eotaxin levels in blood were significantly higher than those in MEE in both groups of patients and in OME patients with asthma than in the control group. In addition, in OME patients with asthma, the percentage of eosinophils and eotaxin levels in blood tended to correlate, but did not reach statistical significance.

CONCLUSION

These data suggest that, in OME patients with asthma, eosinophilia in MEE depends more on IL-5 than on eotaxin, and that eotaxin may play an important role in the mobilization of eosinophils from the bone marrow into the blood.

Clinical characteristics of so called eosinophilic otitis media

OBJECTIVE

Although "eosinophilic otitis media" is not as uncommon a condition as was previously believed, its cause and pathogenesis are not yet fully understood. The purpose of this study was to describe the clinical characteristics in patients with "eosinophilic otitis media" to clarify its pathogenesis.

METHODS

Seven adult patients with persistent and intractable otitis media with viscous middle ear effusion containing many eosinophils, who were also under treatment for bronchial asthma, were studied. The following examinations were conducted: nasopharyngeal endoscopy, pure-tone audiometry, eustachian tube function test, temporal bone CT scan, blood analysis, bacterial and fungal culture of middle ear effusion, histological study of the middle ear and nasal specimens, and measurement of eosinophilic cationic protein (ECP) in middle ear effusion.

RESULTS

Some patients had persistent perforation with papillomatous granulation tissue arising from the mesotympanic mucosa, and all the patients had nasal polyposis. The pure-tone audiometry showed the mixed-type of hearing loss in all the patients, and the hearing level deteriorated progressively during the course in some patients. The eustachian tube function was not always poor but was patulous in some cases. The most severely diseased areas were in the eustachian tube and mesotympanum by temporal bone CT images. All the seven patients had the high levels of total serum IgE, but the RAST scores were negative in three patients and low grade in three patients. The accumulation of eosinophils was observed in middle ear effusion, middle ear mucosa and nasal polyps, and the eosinophils were highly activated with degranulation. High level of ECP was also recovered from middle ear effusion.

CONCLUSIONS

Active eosinophilic inflammation occurs in the entire respiratory tract, including the middle ear in these patients. From our present investigation, we propose the criteria and clinical characteristics of "eosinophilic otitis media".

Eosinophils are activated in middle ear mucosa and middle ear effusion of patients with intractable otitis media associated with bronchial asthma

BACKGROUND

Although patients with intractable otitis media associated with bronchial asthma have extensive accumulation of eosinophils in the middle ear mucosa and middle ear effusion, systematic histological and immunohistochemical studies have not been performed.

OBJECTIVES

To clarify the pathogenesis of middle ear diseases, we carried out immunohistochemical studies on middle ear specimens, particularly focusing on the characteristics of accumulated eosinophils.

METHODS

Middle ear specimens obtained from eight adult patients and from 17 controls were immunohistochemically stained using monoclonal antibodies against EG1, EG2, mast cell tryptase, IgA and IgE. The concentration of eosinophil cationic protein (ECP) in middle ear effusion samples was also measured.

RESULTS

In the asthmatic patients, severe round-cell infiltration was observed in the submucosa and most of the EG1-positive cells were also EG2-positive. In the control patients, the mucosa showed a fibrotic change with a few inflammatory cells, and EG1- or EG2-positive cells were quite few. The expression of IgE was found not only on the surface of mast cells but also within the plasma cells in the asthmatic patients, and the number of IgE-positive cells was about twice as high as that of mast cells. A significantly higher concentration of ECP was noted in middle ear effusion obtained from the asthmatic patients than that from the control patients.

CONCLUSION

Most of the eosinophils in the middle ear mucosa and middle ear effusion were activated, resulting in degranulation and release of ECP, and local IgE production occurs in the middle ear mucosa, indicating that the intractable inflammation is closely associated with IgE-mediated late phase response with eosinophil accumulation.