Microbial Population of Healthy External Auditory Canal

Authors: K. Pokorný 1;  L. Poustecká 2
Authors‘ workplace: Klinika ORL a chirurgie hlavy a krku Krajské nemocnice Pardubice ;  přednosta prof. MUDr. A. Pellant, DrSc. Mikrobiologické oddělení Krajské nemocnice Pardubice 1;  prim. MUDr. L. Poustecká 2
Published in: Otorinolaryng. a Foniat. /Prague/, 56, 2007, No. 1, pp. 7-10.
Category: Original Papers


Anatomy of the external auditory canal tends toward relative stable environment. Nutritions present in cerumen make this relative warm and humid milieu with lack of light appropriate for growth of microorganisms. But the external otitis develops less frequently than could be expected.

Bacterial samples were collected from the cerumen and adequate portion of external auditory canal of 50 persons with normal otoscopic findings. Total bacterial rods isolated were 65 from the external ear canal and 64 from the cerumen. Only in 5 subjects were both samples (ear wax and external ear canal) negative. The predominant bacterial rods were Staphylococcus epidermidis and Staphylococcus aureus. There were also isolated bacteria taken usually for pathogens, as Pseudomonas aeruginosa, Klebsiella pneumoniae a Candida albicans. The paper brings a review of knowledge of factors influencing microbial colonisation of external auditory canal.

The outcome of our and other identical published studies are pointing out the fact that it is necessary to change the perspective of microbiological flora of external ear canal and to relate it to current local finding. Microbes commonly occurring in healthy ears could change in other conditions to pathogens and contribute to ear inflammation, or they could help to preserve the chronic inflammation.

Key words:
healthy external auditory canal, microbial flora, cultivation results.


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Audiology Paediatric ENT ENT (Otorhinolaryngology)
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