ABSTRACT
The diagnosis of chronic otitis media (COM) implies a permanent abnormality of the pars tensa or flaccida, most likely a result of earlier acute otitis media, negative middle ear pressure or otitis media with effusion. It is widely believed that COM often starts with episodes of acute otitis media (AOM) or otitis media with effusion (OME) in childhood. OME may lead to thinning of the tympanic membrane, hearing loss and delayed speech development, and it can impact on the child's educational development. Eosinophilic otitis media is a relatively new subgroup of OM/COM which was first described in Japan. It occurs mainly in patients with bronchial asthma who have T–helper type 2 dominant predisposition, and a patulous Eustachian tube which allows entry of antigenic material into the middle ear resulting in an eosinophilic dominant inflammatory infiltrate. Labyrinthine fistula can be caused by active mucosal COM or cholesteatoma.
