Conditions of the Pinna and the External Auditory Canal - Otitis Externa

Question 1

What is Otitis Externa?

Answer 1

Inflammation of the skin in the external ear canal.

Question 2

Types of Otitis Externa.

Answer 2

1. Acute (<3 Weeks) vs. Chronic (>3 Weeks).

2. Localised vs. Diffuse (Pinna).

Question 3

Why is Otitis Externa also known as Swimmers Ear?

Answer 3

Exposure to water whilst swimming can lead to inflammation in the ear canal.

Question 4

Risk Factors of Otitis Externa.

Answer 4

1. Exposure to Water.

2. Trauma from Ear Canal.

Question 5

Protective Factor of Otitis Externa.

Answer 5

Ear Wax (Cerumen).

Question 6

Aetiology of Otitis Externa (5).

Answer 6

1. Bacterial Infection.
2. Fungal Infection - Aspergillus, Candida.
3. Eczema.
4. Seborrheic Dermatitis.
5. Contact Dermatitis.

Question 7

Aetiology of Fungal Otitis Externa.

Answer 7

Multiple courses of topical antibiotics.

Question 8

Aetiology of Bacterial Otitis Externa.

Answer 8

1. P. aeruginosa.

2. S. aureus.

Question 9

Key Features of P. aeruginosa.

Answer 9

1. Gram-negative Aerobic rod-shaped.
2. CF.
3. Aminoglycosides e.g. Gentamicin or Quinolones e.g. Ciprofloxacin.

Question 10

Clinical Features of Otitis Externa (4).

Answer 10

1. Ear Pain.
2. Discharge.
3. Itchiness.
4. Conductive Hearing Loss.

Question 11

Examination Findings of Otitis Externa (4).

Answer 11

1. Erythema + Swelling in Ear Canal.
2. Tenderness in Ear Canal.
3. Pus/Discharge in Ear Canal.
4. Lymphadenopathy in Neck or Around Ear.

Question 12

Investigations of Otitis Externa (2).

Answer 12

1. Otoscopy - Clinical Diagnosis.

2. Ear Swab - Identify Causative Organism (Not Necessary).

Question 13

Management of MILD Otitis Externa (3).

Answer 13

1. Acetic Acid (EarCalm) - anti fungal and antibacterial effect.
2. Can be used as treatment.
3. Can be used as prophylaxis before/after swimming.

Question 14

Management of MODERATE Otitis Externa (2).

Answer 14

1. Topical Antibiotic AND Steroid (+/- Acetic Acid) e.g. Otomize Spray.
2. Aminoglycosides e.g. Gentamicin, Neomycin are potentially ototoxic if they pass the tympanic membrane so exclude perforation before use (even if it means referral).

Question 15

Management of SEVERE Otitis Externa.

Answer 15

1. Oral antibiotics.

2. Discussion with ENT for admission and IV Antibiotics.

Question 16

Indication of Ear Wick (5).

Answer 16

1. Ear Canal is Swollen.
2. Treatment with Drops/Sprays is Difficult.
3. Made of Sponge and Gauze containing topical treatment.
4. Insert into canal for some time and remove after settling.
5. Use drops/sprays after swelling and inflammation settles.

Question 17

Management of FUNGAL Otitis Externa.

Answer 17

Clotrimazole Ear Drops.

Question 18

Indication of ENT Referral.

Answer 18

Failure to respond to topical antibiotics.

Question 19

What is Malignant Otitis Externa?

Answer 19

Severe and potentially life-threatening form of Otitis Externa - infection spreading to the bones surrounding the ear canal.

Question 20

Complication of Malignant Otitis Externa.

Answer 20

Osteomyelitis of Temporal Bone of Skull.

Question 21

Risk Factors of Malignant Otitis Externa (3).

Answer 21

1. Diabetes.
2. Immunosuppression.
3. HIV.

Question 22

Clinical Presentation of Malignant Otitis Externa.

Answer 22

Symptoms are generally more severe than normal Otitis Externa - persistent temporal headache, severe pain and fever.

Question 23

Key Examination Finding of Malignant Otitis Externa.

Answer 23

Granulation Tissue at Junction between Bone and Cartilage in Ear Canal (1/2 way).

Question 24

Management of Malignant Otitis Externa (3).

Answer 24

EMERGENCY MANAGEMENT :

1. Admission to ENT Team.
2. IV Antibiotics.
3. Imaging (CT/MRI) to Assess Extent.

Question 25

Complications of Malignant Otis Externa (5).

Answer 25

1. Facial Nerve Palsy.
2. CN Nerve Involvement e.g. Glossopharyngeal, Vagus or Accessory.
3. Meningitis.
4. Intracranial Thrombosis.
5. Death.