Acute Otitis externa (AOE) is also known as swimmers ear. As the name suggests, it’s an acute condition. AOE is characterised by diffuse pain in the external ear. This is accompanied with infection of the external ear canal skin and underlying dermis of the external ear.
It’s much more painful than it seems, so should be treated promptly.
Signs & Symptoms of Acute Otitis Externa (swimmers ear)
Signs and symptoms of AOE (actue otitis externa) include:
- Diffuse pain and infection in external ear. The pain and infection are of acute origin.
- Tenderness of tragus and pinna.
- Sometimes temporomandibular joint (TMJ) is tender too due to acute otitis externa.
- Patient has a feeling of fullness in his ear.
- Itch is present.
- Decreased hearing due to canal occlusion occurs secondary to edema.
- The external ear canal can be erythematous with purulent (watery) discharge.
Differential Diagnosis of Acute otitis Externa
Differential diagnosis of Acute Otitis Externa include:
- Acute otitis media with tympanic membrane rupture
- Acute otitis media with otorrhea secondary to a chronic perforation or tympanostomy tube in place
- Herpes zoster / viral otitis externa
- Sequele of foreign body in external ear
- Fungal external otitis
- Contact dermatitis (secondary to contact by offending cosmetics, nickel, drugs, plastic in some hearing aid, etc)
Confirmation of diagnosis of Acute Otitis Externa
Confirmation of diagnosis is based on history and examination of the patient. This includes ruling out the possible differentials.
Causes of Acute Otitis Externa
Acute infection in the external ear occurs due the the disruption of normal epithelial barrier.
This infection is 98% bacterial in origin. Fungal origin is very uncommon.
Acute Otitis Externa usually develops secondary to Pseudomonas aeruginosa infection usually and seldom secondary to Staphylococcus aureus infection.
Risk Factors of Acute Otitis Externa
Risk factors include:
- Trauma from aggressively cleaning ear by the patient
- Removal of wax
- Chronic skin conditions like eczema
- Water exposure (thus named swimmers ear)
Water gets trapped behind the wax when there is enough wax to block the external ear canal. This provides a medium for bacterial growth in the external ear canal.
Treatment of Acute Otitis Externa
Acute Otitis externa (swimmers ear) requires immediate treatment due to severity of the condition.
For pain, medicines used are:
- Opiods such as codeine combined with acetaminophen or anti inflammatory.
Topical therapy via ear drops is the main treatment of choice for acute otits externa.
Bacterial resistance is not a major issue with topical ear drops.
Culturing the discharge from ear is not required prior to treatment.
Irrigation of external ear canal with water and or saline are not recommended in a patient with acute otitis externa. It can even make condition worse.
Oral therapy don’t have any specific use in treatment of acute otitis externa because infection is mostly localised. It’s used usually when the infection has spread to pinna and skin around the ear.
Consider using intravenous therapy in severe cases. Especially when cellulitis has developed.
Treatment is typically effective in first 24-48 hours after which AOE starts to resolve.
Refer the patient to a senior ENT specialist if the condition persists or doesn’t resolve with medication. Ruling out carcinoma (squamous cell carcinoma) may also be required in persistent cases.