Otitis externa

Question 1

Otitis externa, commonly referred to as swimmer’s ear, is an inflammatory condition affecting the external auditory canal and pinna. What is the prevalence of this?

1 - 5000 cases per 100,000
2 - 500 cases per 100,000
3 - 50 cases per 100,000
4 - 5 cases per 100,000

Answer 1

2 - 500 cases per 100,000

Common problem affecting boys and girls equally

Question 2

Otitis externa, commonly referred to as swimmer’s ear, is an inflammatory condition affecting the external auditory canal and pinna. What age does the prevalence of this peak?

1 - 1-5
2 - 10-20
3 - 30-40
4 - 40-50

Answer 2

4 - 40-50

The pinna is the medical name of the outer ear

Question 3

Otitis externa can be acute or chronic. What is the definition of acute Otitis externa?

1 - <2 weeks
2 - <6 weeks
3 - <12 weeks
4 - <16 weeks

Answer 3

2 - <6 weeks

Chronic Otitis externa = >3months

Question 4

There are a myriad of factors that can increase the risk of otitis externa. Which of the following is NOT a risk factor for developing otitis externa?

1 - water exposure
2 - high humidity
3 - male gender
4 - trauma to the auditory canal (cotton wool ear buds)
5 - narrow ear canals
6 - immunosuppression

Answer 4

3 - male gender

Question 5

immunosuppression is a risk factor for otitis externa, but which of the following conditions is otitis externa most common in?

1 - RA
2 - coeliac disease
3 - diabetes
4 - IBD

Answer 5

3 - diabetes

Question 6

Which of the following are common causes of otitis externa?

1 - infection
2 - seborrhoeic dermatitis
3 - contact dermatitis (allergic and irritant)
4 - all of the above

Answer 6

4 - all of the above

Seborrhoeic dermatitis causes red, flaky and itchy rash on your skin. It affects areas of your skin that tend to be greasier, like your face, scalp and chest. It’s also known as seborrhoeic eczema

Question 7

Which of the following skin conditions is most commonly associated with otitis externa?

1 - seborrhoeic dermatitis
2 - psoriasis
3 - uriticaria
4 - acne vulgaris

Answer 7

1 - seborrhoeic dermatitis

Question 8

Infection is a common cause of otitis externa. Which 2 bacteria are commonly associated with otitis externa?

1 - Staphylococcus aureus
2 - Group A ß - hemolytic streptococcus
3 - Streptococcus pneumoniae (Strep)
4 - Pseudomonas aeruginosa

Answer 8

1 - Staphylococcus aureus
4 - Pseudomonas aeruginosa

MUST get a swab for microscopy, culture and sensitivity

Question 9

Which 2 fungi have been associated with causing chronic otitis externa?

1 - Dermatophytes
2 - Tinea barbae
3 - Aspergillus species
4 - Candida albicans

Answer 9

3 - Aspergillus species
4 - Candida albicans

MUST get a swab for microscopy, culture and sensitivity

Question 10

Which of the following are common symptoms in patients describe if they have otitis externa?

1 - otalgia (ear pain)
2 - pruritis (itchy ear)
3 - otorrhea (ear discharge)
4 - reduced hearing
5 - all of the above

Answer 10

5 - all of the above

Question 11

Is the hearing loss in otitis externa conductive or sensorineural in nature?

Answer 11

• conductive

Question 12

When comparing otitis externa and media, which of theses will present with a painful ear when you touch of pull the pinna?

Answer 12

• otitis externa

Question 13

When comparing otitis externa and media, which of theses is more likely to present with an exudate?

Answer 13

• otitis externa

BUT otitis media can present with exudate if the tympanic membrane is perforated

Question 14

When comparing otitis externa and media, which of theses is more likely to present with an erythematous external auditory canal?

Answer 14

• otitis externa

Question 15

Is it always possible to get a clear view of the ear canal in otitis externa?

Answer 15

• no

Maybe obscured due to discharge, debris or swelling

Ear canal may be red, swollen, or eczematous

Question 16

Which of the following are recommended 1st line in patients with suspected otitis externa?

1 - acetic acid spray for 7 days
2 - removal of debris if canal is obstructed
3 - ear wick to reduce inflammation and swelling
4 - all of the above

Answer 16

4 - all of the above

MUST KEEP EAR DRY

Question 17

In otitis externa, which of the following is the first line treatment?

1 - gentamicin with dexamethasone
2 - neomycin with dexamethasone
3 - flumetasone with dexamethasone
4 - co-amoxiclav with dexamethasone

Answer 17

2 - neomycin with dexamethasone

Typically given for 7-14 days as a topical otomize ear spray containing:
- dexamethasone (steroid)
- neomycin sulphate (antibiotic)
- acetic acid

Question 18

In otitis externa, if the infection becomes resistant or severe, which of the following antibiotics are typically given orally?

1 - gentamicin
2 - neomycin
3 - ciprofloxacin
4 - co-amoxiclav

Answer 18

3 - ciprofloxacin

Question 19

if a patient has suspected otitis externa and a perforated tympanic membrane, which antibiotic is typically NOT used?

1 - gentamicin
2 - flucloxacillin
3 - flumetasone
4 - co-amoxiclav

Answer 19

1 - gentamicin

Gentamicin is an aminoglycosides
- associated with ototoxicity and hearing loss

Flucloxacillin can be used as a 2nd line antibiotic if the infection is spreading

Question 20

Necrotising Otitis Externa (NOE)is the spread of infection causing osteomyelitis of the surrounding bones (temporal bone). Which of the following is NOT a typical risk factor for NOE?

1 - immunosuppression, Diabetes Mellitus (esp. poorly controlled)
2 - Elderly
3 - Younger ages (<5)
4 - all of the above

Answer 20

3 - Younger ages (<5)

Question 21

Necrotising Otitis Externa (NOE)is the spread of infection causing osteomyelitis of the surrounding bones (temporal bone). NOE can cause granulation tissue in floor of external ear canal (usually bony-cartilaginous junction). Which of the following is NOT a red flag in patients?

1 - disproportionate ear pain and fever
2 - profound sensorineural hearing loss
3 - ipsilateral facial nerve palsy
4 - all of the above are red flags

Answer 21

2 - profound sensorineural hearing loss

This causes conductive hearing loss

Question 22

Necrotising Otitis Externa (NOE)is the spread of infection causing osteomyelitis of the surrounding bones (temporal bone). NOE can cause granulation tissue in floor of external ear canal (usually bony-cartilaginous junction). It can cause nerve palsies in all of the following cranial nerves, EXCEPT which one?

1 - CN7
2 - CN8
3 - CN9
4 - CN10
5 - CN11
6 - CN12

Answer 22

2 - CN8

This is internal ear, so is less likely to be affected

Question 23

Necrotising Otitis Externa (NOE)is the spread of infection causing osteomyelitis of the surrounding bones (temporal bone). NOE can cause granulation tissue in floor of external ear canal (usually bony-cartilaginous junction). Which of the following is MOST likely to suggest this is NOE more than just otitis externa?

1 - colour of exudate
2 - duration of symptoms
3 - proportion of pain in relation to symptoms
4 - age at onset of symptoms

Answer 23

3 - proportion of pain in relation to symptoms

Question 24

Which of the following blood tests would NOT be routinely performed in a patient suspected of having Necrotising Otitis Externa (NOE)?

1 - FBC
2 - Autoimmune screening
3 - U/Es
4 - CRP/ESR
5 - Blood cultures

Answer 24

2 - Autoimmune screening

ESR is specifically good as it can be used as a marker of antibiotic response

Would also want to sample the granulation tissue in the ear to exclude small cell carcinoma

Question 25

Which of the following imaging modalities is most likely to be performed in a patient with suspected Necrotising Otitis Externa (NOE)?

1 - angiogram
2 - head MRI
3 - head X-ray
4 - head CT

Answer 25

4 - head CT

Specifically interested in the temporal bone

Question 26

When treating Necrotising Otitis Externa (NOE) the local microbiologist should be consulted on antibiotic prescription. Typically how long do these patients take antibiotics for?

1 - 2 weeks
2 - 6 weeks
3 - 12 weeks
4 - 24 weeks

Answer 26

2 - 6 weeks

Must get control of blood sugars and provide analgesia as well

Question 27

Are oral antibiotics useful in treating Necrotising Otitis Externa (NOE)?

Answer 27

• No

Need to use topical and sometimes systemic via IV as well

Question 28

In Necrotising Otitis Externa (NOE) patients can suffer with facial nerve palsy. Which of the following should patients receive?

1 - lubricating eye drops
2 - lubricating eye drops and tape eyes at night
3 - chloramphenicol
4 - intravenous acetazolamide

Answer 28

2 - lubricating eye drops and tape eyes at night

Patients are unable to close their eyes

Question 29

In Necrotising Otitis Externa (NOE) patients can suffer with glossopharyngeal nerve palsy. Which of the following should they receive if this is the case?

1 - liquid only diet
2 - soft food and liquid diet
3 - enteral feeding
4 - parenteral nutrition

Answer 29

3 - enteral feeding

PEG feeding is an example of this

Common side effect is diarrhoea

Question 30

Does Necrotising Otitis Externa (NOE) have a good mortality rate?

Answer 30

• no

Despite treatment, mortality rates are poor