Acute Otitis Externa Flashcards
Otitis externa refers to inflammation of the…
Otitis externa refers to inflammation of the external auditory canal.
Acute otitis externa
Though the inflammation can have many causes (e.g. allergic, dermatologic), infection, in particular by bacteria, is the most common cause.
It may be categorised (definition from NICE CKS) as:
Acute: lasts 3 weeks or less
Chronic: lasts 3 months or longer
Malignant otitis externa (MOE) is a rare life-threatening condition where the infection spreads to the surrounding ….
Malignant otitis externa (MOE) is a rare life-threatening condition where the infection spreads to the surrounding bone.
Epidemiology of acute otitis Externa
Up to 10% of people will experience acute otitis externa in their lifetime.
Epidemiology of acute otitis externa
Though otitis externa (both acute and chronic) can occur at any age, it is more common in children and adolescents, with incidence peaking around the ages of 7-12.
Prevalence is greater towards the end of the summer and it is slightly more common in women.
Risk factors for acute otitis externa
Acute otitis externa is sometimes called swimmers ear because of its increased incidence in swimmers.
Swimming
Humid air
Young age
Diabetes
Trauma
Narrow external auditory meatus
Obstructed external auditory meatus
Eczema, psoriasis
Radiotherapy
Aetiology of acute otitis externa
Bacterial infection accounts for up to 98% of cases of acute otitis externa.
Infection - acute otitis externa
Bacterial infection is the most common cause of acute otitis externa. Pseudomonas aeruginosa or Staphylococcus aureus is most frequently implicated.
Fungal pathogens may also result in otitis externa, commonly Candida albicans or Aspergillus species.
Clinical features
Acute otitis externa
Acute otitis externa often presents with ear pain and itchiness.
Patients tend to present with a short history of otalgia (ear pain), frequently associated with discharge. In more severe cases swelling of the external auditory canal and debris may result in hearing loss.
Symptoms
Itch
Tenderness
Hearing loss
Discharge
Signs
Inflamed external auditory canal
Erythema
Scaly skin
Pre-auricular lymphadenopathy
Symptoms + Signs of acute otitis externa?
Symptoms
Itch
Tenderness
Hearing loss
Discharge
Signs
Inflamed external auditory canal
Erythema
Scaly skin
Pre-auricular lymphadenopathy
Management of acute otitis externa
Treatment normally takes the form of analgesia and topical therapies.
Investigations - acute otitis externa
In many cases, no investigations beyond a thorough history and examination are needed. If the presentation is atypical, recurrent or treatment-resistant, an ear swab, sent for MC&S may be of use.
Treatment of acute otitis externa
Treatment
Consideration should be given to any underlying cause and how that may be treated. Cleaning of the external canal can be needed. Patients should avoid swimming for a minimum of 7-10 days.
Analgesia: paracetamol and ibuprofen (if no contraindications).
Topical therapy: topical antibiotics +/- a topical steroid may be given.
Are antibiotics typically indicated for acute otitis externa?
Topical antibiotics may be given
Oral antibiotics are rarely indicated and should prompt discussion with ENT. Any patient who is systemically unwell should be urgently reviewed by ENT.
NOTE: Clinicians should be alert to severe infection and malignant otitis externa. This is seen in particular in the elderly and patients with diabetes or a compromised immune system.
Preventing acute otitis externa
The ears should be kept clean and dry whilst trauma must be avoided. Earplugs or a swimming cap can help reduce the incidence.
If a precipitating factor, allergies should be identified and avoided whilst dermatological conditions should be optimally treated.
There are acidifying ear drops that can be used prior to sleeping or before and after swimming that may reduce the incidence of otitis externa.
