W31 Otitis Externa and Earwax Flashcards
What is otitis externa?
Otitis externa describes diffuse inflammation of the skin and subdermis of the external ear canal, which may also involve the pinna or tympanic membrane.
What are the types of otitis external? (3)
- Acute otitis externa – inflammation < 6 weeks, typically caused by bacterial infection with Pseudomonas aeruginosa or Staphylococcus aureus
- Chronic otitis externa – inflammation > 3 months and may be caused by fungal infection with Aspergillus species or Candida albicans
- Malignant otitis externa – potentially life-threatening progressive infection of the external ear canal causing osteomyelitis of the temporal bone and adjacent structures
Epidemiology of otitis externa: (for info)
More common in men or women?
- A common diagnosis in all age groups
- More common in females than in males up to the age of 65 years (opp to AOM)
- Prevalence increased at the end of the summer, especially in those aged 5–19 years
What are the risk factors for Acute otitis externa?
- Skin conditions – produce debris in the ear canal which can encourage infection
- Acute otitis media – purulent middle ear secretions may enter the external ear canal if there is tympanic membrane perforation
- Contact dermatitis – caused by a local irritant or allergen
- Trauma to the ear canal – may be from ear cleaning
- Foreign body in the ear – use of hearing aids, or ear plugs
- Diabetes (Chronic otitis externa)
- Antibiotic use (Chronic otitis externa)
Signs and diagnosis of AOE:
At least two typical signs:
- Tenderness of the tragus and/or pinna.
- The ear canal is red and oedematous, and there may be debris and ear discharge contributing to swelling and canal occlusion.
- Tympanic membrane erythema (may be difficult to visualize if the ear canal is narrowed or filled with debris).
- Cellulitis of the pinna and adjacent skin.
- Conductive hearing loss (less common).
- Tender regional lymphadenitis (less common).
What are the presenting symptoms that can help to diagnose AOE?
At least one typical symptom (usually rapid-onset within 48 hours):
* Itch of the ear canal.
* Ear pain and tenderness of the tragus and/or pinna (often severe), with possible jaw pain.
* Ear discharge.
* Hearing loss due to ear canal occlusion (less
common).
How to assess a person with suspected otitis externa: Symptoms
The onset, nature, and severity of symptoms, such as:
* Pain or tenderness on moving the ear (tragus or pinna) or jaw
* Ear discharge
* Itch in the ear canal
* Fever
* Hearing loss (conductive)
- Impact on daily functioning and quality of life
- Any possible causes or risk factors, including recent ear trauma, use of hearing aids or ear plugs, history of head or neck radiotherapy
- Any previous episodes and topical or oral treatments used.
- Any previous ear surgery, perforation of the tympanic membrane and/or tympanostomy tube insertion within the previous year
- Any history of allergic or irritant contact dermatitis
- Any comorbidities such as diabetes mellitus or other causes of immunocompromise
How to assess a person with suspected otitis externa: Examine the person’s ears
Note: it can be difficult to adequately visualize the tympanic membrane on initial presentation
What signs should you look for?
- Assess the ear canal, tympanic membrane, pinna, auricular, and cervical lymph nodes for
possible signs: - Red, oedematous ear canal which may be narrowed and obscured by debris.
- Ear discharge (serous or purulent).
- Signs of fungal infection (such as white strands of Candida, or small black or white balls of
Aspergillus). - Regional lymphadenopathy.
- Cellulitis spreading beyond the ear
- Assess for a perforation of the tympanic membrane, including a tympanostomy tube in situ
- Assess the surrounding skin for associated skin disorders suggesting a possible underlying
cause or alternative condition
Management of AOE:
What are the self-care measures?
Keep ear clean and dry:
* Avoid swimming and water sports for at least 7–10 days during treatment
* Use ear plugs and/or a tight-fighting cap when swimming
* Keep shampoo, soap, and water out of the ear when bathing and showering, for example by inserting ear plugs or cotton wool (with petroleum jelly)
* Consider using a hair dryer to dry the ear canal after hair washing, bathing, or swimming.
* Avoid damage to the external ear canal – avoid the use of cotton buds
* Consider use of OTC acetic acid 2% ear drops or spray (for people aged 12 years and older) morning, evening, and after swimming, showering, or bathing, for a maximum of 7 days
Management of AOE:
- Manage any underlying condition
- Analgesia – paracetamol or ibuprofen if needed
- Consider cleaning the external auditory canal (‘aural toilet’) – to enable topical treatments to be applied effectively
Management of AOE:
What is the pharmacological treatment?
- Consider prescribing a topical antibiotic preparation with or without a topical corticosteroid for 7–14 days, depending on clinical judgement and symptom response
-Antibiotic: aminoglycoside or fluroquinolone - Consider prescribing an oral antibiotic if the person is immunocompromised, there is severe infection, or there is spread beyond the external ear canal
- For chronic otitis externa, consider a topical antifungal preparation, such as clotrimazole 1% solution or clioquinol and a corticosteroid
What is the contraindication for topical ear preparations?
- Ototoxicity and contact sensitivity reactions
- Topical aminoglycoside preparations are contraindicated in people with a perforated tympanic membrane due to the risk of ototoxicity, but may be used on the advice of
a specialist.
=Prescribe a non-ototoxic preparation if the person has a known or suspected perforation of the tympanic membrane, including a tympanostomy tube in situ. - If there is a history of suspected contact sensitivity to a topical ear preparation, advise to avoid all preparations with the same class of drug associated with the reaction.
Safety netting:
When to arrange follow up?
Arrange follow up to reassess the person if:
* Symptoms are not improving within 48–72 hours (2-3 days)
* Symptoms have not fully resolved after 2 weeks
* Symptoms are severe and/or there is cellulitis spreading beyond the external ear canal
* The person is immunocompromised and at risk of severe infection
* There is ear wax impaction or stenosis of the ear canal which prevents the tympanic membrane being visualized
AOE Vs AOM:
1. What do we see on otoscope?
2. Bacteria?
AOE: good tympanic membrane mobility
AOM: impaired mobility and associated
middle ear effusion
AOE: Pseudomonas, S. Aureus
AOM:
*Usually comes after a viral infection
*URTI bugs (most likely enters the middle
ear cleft via the Eustachian tube)
*Strep.pneumoniae
*Haemophilus influenzae
*Moraxella catarhalis
*Strep. Pyogenes (to a lesser extent)
Acute diffuse otitis externa vs Acute otitis media
Main cause (s)
AOE: Mostly, Swimming, Mechanical damage
AOM: Mostly URTI, second hand smoke, use
of dummy
Treat with antibiotics?
AOE: Yes in most cases. Use topical
agents after dry aural toilet –Refer to doctor
AOM: If no risk factors, wait for 48-72 hours
Oral agents for treatment (or
topical anaesthetic/analgesic)
Prevention
AOE: Keeping ears dry, Using acetic acid eardrops
AOM: Avoid colds, smoke, dummy, vaccinations
OTC relief:
Both: Paracetamol/Ibuprofen
