Otitis externa (OE)

Question 1

Basic info

Answer 1

Its is Inflammation of the ear canal.
(ear canal is the tube between the outer ear and the tympanic membrane).
Water exposure makes the ear more vulnerable.

Acute inflammation <6 weeks typical cause is bacterial infection
Chronic inflammation >3 months and can be caused by fungal infection.
Malignant OE life threatening.

Question 2

Symptoms/Causes/ Risk factors

Answer 2

Symptoms:
*Ear pain, can be severe.
*Itchiness in the ear canal.
*Discharge of liquid/pus from ear.
*Temporary hearing loss.
*Usually, only one ear is affected
*Red ear
* Chronic - dry scaly skin, itch

Causes:
*Seborrhoeic dermatitis – skin condition = greasy areas of the skin become irritated and inflamed
*Bacterial infection
*Fungal infections - more common if patients use antibacterial or steroid ear drops for a long time.
*otitis media – discharge produced by an infection deeper in the ear can sometimes lead to otitis externa.
*Irritation/allergies- reaction to something that comes into contact with the ears.

Risk factors:
Acute -
Skin damage inside ear (scratching)
Obstruction/Trauma to ear canal
Water in the ear regularly
Conditions like eczema, asthma, allergic rhinitis, acute OM.

Chronic-
DM, immunosuppression, fungal infection from long term meds use (mention above).

Question 3

Diagnosis/Treatment

Answer 3

Otoscope, full history (socrates, risk factors, etc), Swab if recurrent/chronic or infection sus.

Treatment:
Can clear on its own in weeks. with treatment a few days.
Monotherapy with antibiotics or
Dual antibiotics + steroid

ACUTE:
Advise on self care measures -
- keep ears clean, no buds, avoid water sports 7-10 days, keep shampoo soap water out of ear when bathing (ear plugs), try hair dryer to dry ear canal.

Can use OTC acetic acid (treats OE infection) (>12yrs) morning evening and after shower/swimming MAX 7 days.

Manage underlying causes
Can use analgesia
Can clean the external canal (aural toilet) helps use meds better.

Can Prescribe:
Topical antibiotics +/- Topical corticosteroid 7-14 days.
- choice depends on patients pref, risk of AE, cost, dosing, etc.
IF immunocompromised or SEVERE can use oral antibiotics.

EXAMPLES of used drugs:
Otomize, Sordafex, Gentisone, FML drops, Clotrimazole (fungal), Betnesol/N. (MOA pack y3)

Oral: (Severe cases only, applies to chronic too)
Pseudomonas sus - Ciprofloxacin (or an aminoglycoside).
No P allergy Flucloxacillin.
ALT Clarithromycin (or azithromycin or erythromycin).

CHRONIC:
Non pharmacological same as above.
Prescribe:
Consider Topical ear preparation:
Fungal infection -
- Topical antifungal, eg clotrimazole 1% solution 2–3/day, continued for at least 14 days after infection resolved.
- Clioquinol + corticosteroid 2–3 drops BD for 7–10 days.
- Acetic acid same as above

Bacterial infection:
- Use same treatment as acute OE

No obvious bacterial or fungal infection:
- Topical corticosteroid eg prednisolone ear drops 2–3 drops every 2–3 hours until symptoms improve, or
Betamethasone ear drops 2–3 drops 3–4/day. If symptoms improve, continue treatment using the lowest potency and/or frequency of application needed to control symptoms.
- If symptoms persist, consider a trial of topical antifungal instead.

Question 4

Complication

Answer 4

Malignant otitis externa
Urgent referral.
Infection spreads to surrounding bone.
Treat ASAP with Antibiotics and surgery.
Risk factors:
Diabetes, chemotherapy, weakened immune system
SYMPTOMS:
*Ongoing drainage from the ear that is yellow or green and smells bad.
*Ear pain deep inside the ear. Pain may get worse when you move your head.
*Hearing loss.
*Itching of the ear or ear canal.
*Fever.
*Trouble swallowing.
*Weakness in the muscles of the face.

Avoid cotton buds and fingers in the ear canal. swimmers to use ear plugs when swimming. Avoid soap/shampoo in the ear when shower or bathing

Question 5

Follow up

Answer 5

ACUTE:
Reasses in 48-72 hrs if symptoms not improving or
Not resolved in 2 weeks or
Severe symptoms or
Immunocompromised and at infection risk or
To much wax.

Chronic:
If symptoms worsen or Immunocompromised with infection risk

Refer if: (chronic and acute)
ENT if malignant OE sus.
Or no improvement after long usage or elder with poor DM, or cellulits beyond ear.