From the Research
Introduction to External Otitis
External otitis, also known as otitis externa, is an inflammation of the outer ear canal, typically caused by infection, although it can also be associated with noninfectious systemic or local dermatologic processes 1.
Risk Factors
Several factors can increase the risk of developing external otitis, including:
- Excessive moisture and trauma, which impair the canal's natural defenses 1
- Eczema of the ear canal 2, 3
- Swimming, especially in humid environments 2, 3
- Narrow ear canals 2, 3
- Hearing-aid use 2, 3
- Mechanical trauma 2, 3
- Immunocompromised status, which can lead to more severe forms like necrotizing otitis externa 4
Prevention Methods
Prevention is key in managing external otitis, and the following methods can help:
- Avoiding excessive moisture and trauma to the ear canal 1
- Drying the ears with a hair dryer after exposure to moisture 1
- Avoiding manipulation of the external auditory canal 1
- Using topical solutions like 2 percent acetic acid combined with hydrocortisone for inflammation after exposure to moisture as a prophylactic measure 1
Signs and Symptoms
The characteristic symptoms and signs of external otitis include:
- Discomfort limited to the external auditory canal 1
- Erythema and swelling of the canal with variable discharge 1
Treatment Options
Treatment for external otitis depends on the severity and cause but typically involves:
- Topical antibiotic and steroid preparations for acute otitis externa 5
- Specialist aural toilet, topical acetic acid, topical aluminium acetate, topical antibacterials, topical antifungals, and topical corticosteroids for various forms of otitis externa 2, 3
- Systemic antibiotics may be required in complicated cases or in immunocompromised patients 4
- Pain management and education on preventing recurrence are also crucial components of treatment 4
Treatment Considerations
When treating external otitis, it's essential to:
- Identify and address any underlying causes, especially in chronic cases 5
- Consider the patient's overall health status, particularly if they are immunosuppressed 4
- Monitor for signs of complications, such as necrotizing otitis externa, especially in at-risk populations 4
Differential Diagnosis and Caveats
Differential diagnosis should consider other conditions that may present with similar symptoms, such as:
- Eczema or other dermatologic conditions of the ear canal
- Middle ear infections (otitis media)
- It's crucial to perform a thorough history taking and physical examination to differentiate among acute, chronic, and necrotizing otitis externa 4