External otitis: Pathogenesis, clinical features, and diagnosis
- Laura A Goguen, MD
Laura A Goguen, MD
- Associate Professor in Otology and Laryngology
- Harvard Medical School
- Section Editors
- Daniel G Deschler, MD, FACS
Daniel G Deschler, MD, FACS
- Section Editor — Otorhinolaryngology
- Professor of Otology and Laryngology
- Harvard Medical School
- Morven S Edwards, MD
Morven S Edwards, MD
- Section Editor — Pediatric Infectious Diseases
- Professor of Pediatrics
- Baylor College of Medicine
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 .
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 . 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 :
●7 percent ages 0 to 4 years
●19 percent ages 5 to 9 years
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- PATHOGENESIS AND RISK FACTORS
- CLINICAL FEATURES
- DIFFERENTIAL DIAGNOSIS
- Contact dermatitis
- Chronic suppurative otitis media
- Carcinoma of the ear canal
- Malignant external otitis
- INFORMATION FOR PATIENTS
- SUMMARY AND RECOMMENDATIONS