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External otitis: Pathogenesis, clinical features, and diagnosis

Laura A Goguen, MD
Section Editors
Daniel G Deschler, MD, FACS
Morven S Edwards, MD
Deputy Editor
Daniel J Sullivan, MD, MPH


The term external otitis (also known as otitis externa or swimmer’s ear) refers to inflammation of the external auditory canal. Infectious, allergic, and dermatologic disease may all lead to external otitis. Acute bacterial infection is the most common cause of external otitis [1].

This topic will focus on the pathogenesis, clinical features, and diagnosis of external otitis. The treatment of external otitis is discussed in detail elsewhere. (See "External otitis: Treatment".)


External otitis can occur in all age groups [2]. An estimated 10 percent of people develop external otitis during their lifetime. Annual rates of ambulatory care visits in the United States for external otitis are highest during childhood and decrease with age [3]:

7 percent ages 0 to 4 years

19 percent ages 5 to 9 years

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Literature review current through: Nov 2017. | This topic last updated: Dec 05, 2017.
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