Levels of eosinophil cationic protein and myeloperoxidase from chronic middle ear effusion in patients with allergy and/or acute infection.

BACKGROUND AND OBJECTIVE: Allergy may play a role in the middle ear inflammation that leads to otitis media with effusion. The purpose of this study was to determine whether an elevated mediator correlated with the patient's disease and thus could be used to differentiate allergy vs. infection as the cause of the middle ear inflammation. METHODS: We evaluated 57 individuals with otitis media with effusion, 32 with persistent effusion but no recent acute infection, 14 with recent infection and purulent otitis media with effusion, and II healthy subjects. The mediator activity of eosinophils and neutrophils in effusion was studied in patients characterized as having allergy by positive intradermal skin test results and positive radioallergosorbent test results, Eosinophils were characterized by measurement of eosinophil cationic protein in the effusion. Neutrophils were characterized by measurement of myeloperoxidase in the effusion. The levels of eosinophil cationic protein and myeloperoxidase in patients with and without allergy were correlated to patient history. RESULTS: Significantly elevated levels of both eosinophil cationic protein and myeloperoxidase indicated that inflammation in the ear of patients with otitis media with effusion was characterized by a pronounced involvement of both eosinophils and neutrophils, Eighty-nine percent of all patients with disease had allergy. A higher ratio of myeloperoxidase to eosinophil cationic protein in patients with purulent otitis media with effusion indicated that in patients with a superimposed acute infection, neutrophil activity was increased even further. The level of eosinophil cationic protein was elevated only during the effusion of patients with allergies as compared with controls (p < 0.01). Among 29 cases of nonpurulent otitis media with effusion, 96.5% had allergic immune-mediated disease proved by skin testing, which was related clinically to their ear disease. Eighty-nine percent (89.6%) of these patients had eosinophil cationic protein levels greater than 10 mu g/L. CONCLUSION: Middle ear eosinophil cationic protein may be used as a marker of related allergy.