Introduction: Eosinophilic otitis media (EOM) is an intractable otitis media characterized by the presence of a highly viscous yellow effusion containing eosinophils. It mainly occurs in patients with bronchial asthma and is resistant to conventional treatments for otitis media.
Methods: We reviewed 138 patients with EOM and 134 age-matched patients with common type of otitis media to analyze their clinical characteristics and to make diagnostic criteria of EOM.
Results: EOM predominantly affects females and occurs most often in patients in their 50s. EOM is often complicated by rhinosinusitis and nasal polyposis, which is called eosinophilic rhinosinusitis. High tone loss is more frequently found and more severe in EOM patients than in COM control patients. According to the clinical data, we proposed the diagnostic criteria of EOM. Major criterion is that otitis media with effusion or chronic otitis media with eosinophil dominant effusion. It is necessary to prove the accumulation of eosinophils in the effusion histologically or cytologically. Minor criteria are as follows; 1) highly viscous middle ear effusion, 2) resistance to conventional treatment for otitis media, 3) association with bronchial asthma, 4) association with nasal polyposis. The definite case is defined as positive for major and two or more minor criteria. However, eosinophilic granulomatous polyangitis (Churg-Strauss syndrome) and hypereosinophilic syndrome are excluded.
Discussion and conclusion: Our basic treatment for EOM is the intratympanic instillation of triamcinolone. Most of the patients have been well-controlled by this treatment. We further discussed the risk factors of severity and inner ear damage in patients with EOM. Patients with ear symptoms should have the proper diagnosis of EOM using the proposed diagnostic criteria, and then can receive adequate treatment, resulting in prevention of deterioration of hearing and quality of life.