Otology - otalgia and otitis externa

Question 1

What do we call ear pain?

Answer 1

Otalgia

Question 2

What are the causes of otalgia associated with the external ear?

Answer 2

Wax impaction

Otitis externa

Malignant otitis externa

Furuncle (infection of hair follicle)

Malignancy of external canal

Question 3

Other than the external and middle ear, where else can otalgia originate from?

Answer 3

Disorders of the temporomandibular joint

Periauricular lymphadenopathy

Referred pain from any of the nerves with sensory input to the ear

Question 4

What are the nerves that have a sensory input to the ear and therefore can cause referred pain?

Answer 4

Vestibulo-cochlear - Ramsay Hunt syndrome

Facial nerve - Bell’s palsy

Glossopharyngeal nerve - Tonsilitis, especially quinsy, glossopharyngeal neuralgia

Trigeminal nerve - dental pain, nasal and paranasal sinus malignancy

Vagus nerve - laryngeal, pharyngeal and oesophageal pathology

Cervical plexus - C2, C3 root lesions

Question 5

What is otitis externa?

Answer 5

Inflammation of the external ear canal skin and external auditory meatus (ear canal)

Question 6

What are the causes of otitis externa?

Answer 6

Infection (bacterial and fungal)

Seborrhoeic dermatitis

Contact dermatitis

Caused by..
Moisture (swimming, surfing, daily hair wash),
Trauma (eg fingernails, cottonbuds), absence of wax, hearing aid, DM etc…

Question 7

What are the organisms most commonly responsible for infective otitis externa?

Answer 7

Bacteria:

Staphylococcus aureus

Pseudomonas aeruginosa

Fungi:

Candida

Aspergillus

Question 8

What are the risk factors for developing infective otitis externa?

Answer 8

Swimming

Scratching with dirty fingernail

Canal exostoses (bone growth into canal due to prolonged exposure to cold water - surfer’s ear)

Question 9

What are the symptoms of infective otitis externa?

Answer 9

Ear pain (otalgia)

Otorrhoea/discharge (watery, thick in acute, blood in chronic)

Itching

Discharge

Hearing loss (from blockage)

Question 10

On otoscopy of someone with infective otitis externa, what might you see?

Answer 10

Erythema

Inflammation and oedema

Discharge

Fungal spores may be seen (pigmented if Aspergillus)

Tympanic membrane may be ruptured

Question 11

How do we manage someone with an itchy, otalgic ear which otoscopy suggests is due to infective otitis externa?

Answer 11

Swab the ear for cultures

Mechanical cleaning with micro suction + aural toilet (regular cleaning)

Analgesia

First line for mild case (mild discomfort and pruritus) is acetic acid.

Moderate/severe (pain, deafness, discharge) topical combination of antibiotic and corticosteroid - in the form of ear drops.

If really severe oral antibiotic

Patient told to keep ear dry

Question 12

What antibiotic/steroid combination ear drops are classically given to those who present with signs and symptoms of more severe infective otitis externa?

Answer 12

Gentamicin/hydrocortisone

Neomycin/betamethasone

Both of these antibiotics are aminoglycosides

Givem 7-14 daus

Question 13

What are the contraindications for using topical aminoglycosides such as gentamicin or neomycin in the treatment of infective otitis externa?

Answer 13

Perforation of tympanic membrane

If contact dermatitis is suspected - they can cause this

Question 14

What oral antibiotics should be used in someone with severe spreading infective otitis externa?

Answer 14

First line - Flucloxacillin

Question 15

What oral antibiotics should be used in someone with severe spreading infective otitis externa who is allergic to penicillin and therefore cannot have the first line which is flucloxacillin?

Answer 15

Erythromycin

If they do not tolerate this then clarithromycin

Question 16

What is the other name for malignant otitis externa?

Answer 16

Necrotizing otitis externa

Question 17

What is necrotizing (malignant) otitis externa?

Answer 17

A potentially life threatening condition where there is extension of infection into the bony ear canal and the soft tissues deep to the bony canal. Can lead to temporal bone destruction and base of skull osteomyelitis.

Question 18

Who is most often affected by necrotizing (malignant) otitis externa?

Answer 18

Elderly diabetic patients, or those who are immunocompromised

Question 19

What is the organisms most commonly responsible for necrotizing otitis externa?

Answer 19

Pseudomonas aeruginosa in 90%

Question 20

What are the clinical features of malignant (necrotizing) otitis externa?

Answer 20

Deep seated otalgia

Resistant to usual treatment

Facial soft tissue swelling

Suppuration - copious otorrhoea

Oedema

Florid granulation tissue

Spreading osteomyelitis may produce cranial nerve palsies (facial, vagus, hypoglossal)

Fever

Malaise

Loss of diabetic control

Question 21

What are the complications of necrotizing (malignant) otitis externa?

Answer 21

Without aggressive treatment may lead to meningitis, encephalitis and death

Question 22

What investigations might you do for someone in whom you suspected necrotizing (malignant) otitis externa?

Answer 22

Blood sugars

Cultures

FBC, CRP, U&Es

Ear swabs

High resolution CT - rule out encephalitis

Technetium bone scan - rule out osteomyelitis

HIV test in younger or immunocompromised patient

Question 23

How would you manage someone with necrotizing (malignant) otitis externa?

Answer 23

Admission to hospital

IV and topical antibiotics for up to 6 weeks - ciprofloxacin (although there is evolving resistance)

Control of blood sugars

Daily microsuction of ear canal

Analgesia

Failure to respond to these measures:
May require surgical debridement

Question 24

What is an external ear furuncle?

Answer 24

Infection or blockage of a hair follicle of cartilaginous portion of the ear

Question 25

How do you manage a external ear furuncle?

Answer 25

Treatment involves incision of the furuncle under local anaesthetic following which pain and oedema should settle quickly

Question 26

Describe a mild otitis externa

Answer 26

Scaly skin, some erythema

Question 27

Describe a moderate otitis externa

Answer 27

Painful ear, narrowed ear canal and creamy discharge

Question 28

Describe a severe otitis externa

Answer 28

Ear canal occluded