THE PRESENCE OF EOSINOPHIL CATIONIC PROTEIN IN MIDDLE-EAR EFFUSION

Eosinophil cationic protein (ECP) is probably responsible for the unde rlying inflammatory mechanisms seen in asthma. It can be modulated in vivo by immunotherapy or steroids, with an appropriate reduction in sy mptoms of respiratory tract diseases. ECP is an identifiable mediator in additional target organs involved in allergic reactions, making it of potential interest in the study of otitis media with effusion. A qu alitative prospective study was designed to discover the relationship of ECP and serum IgE in patients with middle ear effusion and allergy, as demonstrated by RAST and skin testing. The concentrations of ECP i n the middle ear fluid from 23 consecutive patients with otitis media with effusion undergoing the placement of tympanostomy tubes ranged fr om 2 to 1248 mug (normal serum ECP, 5 to 15 mug), with 87% being abnor mally elevated. There was no correlation between an individual's ear a nd serum levels of ECP (r = 0.1672; p = 0.6232), suggesting a more loc alized process. There was no relation between effusion ECP and serum I gE (p = 0.0040). ECP from middle ear effusion did correlate with a pat ient's having allergy, as confirmed by RAST and skin testing (p = 0.00 95). Mechanisms involving immune mediated disease in the middle ear, o f which the eosinophil may be one participant, are resented,