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When the physician looks in the ear, the canal appears red and swollen in well-developed cases of acute external otitis. The ear canal may also appear eczema-like, with scaly shedding of skin. Touching or moving the outer ear increases the pain, and this maneuver on physical exam is very important in establishing the clinical diagnosis. It may be difficult for the physician to see the eardrum with an otoscope at the initial examination because of narrowing of the ear canal from inflammation and the presence of drainage and debris. Sometimes the diagnosis of external otitis is presumptive and return visits are required to fully examine the ear. Culture of the drainage may identify the bacteria or fungus causing infection, but is not part of the routine diagnostic evaluation.
The diagnosis may be missed in early cases because the examination of the ear, with the exception of pain with manipulation, is normal or nearly normal. In some cases of early external otitis, the most striking visual finding in the ear canal is the lack of cerumen. As a moderate or severe case of externa otitis resolves, weeks may be required before the ear canal again shows a normal amount of cerumen.
Differentiating between otitis externa and otitis media
The second type of common "earache" is otitis media, and this inflammation of the tympanic membrane and middle ear space is usually clinically distinct from otitis externa. However, the conditions are sometimes confused - particularly when there is drainage from the ear (otorrhea). In middle-ear infections, drainage only occurs if the tympanic membrane has either a perforation or retraction pocket. When there is chronic suppurative otitis media, with or without cholesteatoma, the drainage in the ear canal may appear identical to drainage from external otitis. In otitis media, however, there is no tenderness of the ear - no increased pain with pulling the auricle or pushing the tragus. Children with ear tubes who develop an episode of otitis media despite having open myringotomy tubes generally will develop drainage through the tubes. This is not external otitis, but otitis media.
Quinolone antibiotics in topical form (ear drops) have been shown to be of benefit in stopping discharge from otitis media through an open eardrum, and so some treatments for otitis externa may be of benefit to otitis media.The main pitfall of having a case of otitis media misdiagnosed as otitis externa is that a serious infection of the middle-ear may have complications and sequelae over time. Additionally, many types of topical ear drops that are safe and effective for use in the ear canal can be irritating and even damaging if allowed past the ear drum into the more delicate internal membranes of the middle-ear, prompting the warning that such topical preparations should not be used unless the tympanic membrane is known to be intact. For both reasons, caution is given against self-treatment of "earache" without proper medical evaluation.
If there is prolonged drainage of noxious substances from the middle ear through the ear drum, then the skin of the ear canal may become secondarily inflamed. In this situation, one that occurs only in individuals with severe chronic otitis media, both external otitis and otitis media are present at that same time. Prolonged care by a qualified specialist is generally required.
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Important notice:
The content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other
qualified health provider with any questions you may have regarding a medical condition.
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