External auditory canal microbiology and hearing aid use

ObjectiveThe aim of this study was to determine the presence and nature of bacterial flora on hearing aids and the ears of this population. We wonder if the microbiology of the ears with hearing aid wearing differs from the other ear.SettingTertiary referral center.DesignA prospective, clinical study.Subjects and methodsThree samples were taken, one from the surface of the hearing aid's ear mold; one from the hearing aid-wearing ear canal and the last one from the ear without hearing aid. Samples were cultured to determine qualitatively and quantitatively the pathogenic microorganisms present.ResultsA total of 123 samples, obtained from 41 hearing aid users, were analyzed. Methicillin-resistant coagulase-negative staphylococci, methicillin-susceptible Staphylococcus aureus, methicillin-resistant S. aureus, Pseudomonas aeruginosa, Escherichia coli, Acinetobacter species, Staphylococcus auricularis, and Stenotrophomonas maltophilia were identified organisms.ConclusionsWe identified unexpected microorganisms both on hearing aids and hearing aid using ears. This study demonstrates that using hearing aid alters the ear canal flora. To avoid otitis externa, it is important to use an appropriate hygiene routine to clean and disinfect hearing aids and ear molds.