otitis externa

Question 1

what is otitis external?

Answer 1

inflammation of the outer ear canal

Question 2

who does otitis external most commonly affect?

Answer 2

adults

Question 3

what is the cause of otitis external commonly?

Answer 3

always infective but may simply be inflammatory (e.g. response to shampoo, ear drops)

Question 4

what are some of the bacterial causes ?

Answer 4

Staph. aureus

Proteus spp.

Pseudomonas aeruginosa

Question 5

what are some of the fungal causes?

Answer 5

aspergillus niger - swimming common in Dundee

Candida albicans

Question 6

what are the most common triggers of otitis externa?

Answer 6

‘swimmers ear’ - aspergillis niger

water exposure
cotton buds
skin conditions

Question 7

how does otitis externa present?

Answer 7

Redness and swelling of the skin of the ear canal

May be itchy (especially in the early stages)

Can become sore and painful

Question 8

what might cause the tympanic membrane to be obstructed?

Answer 8

discharge, or increased amounts of ear wax

Question 9

if the tympanic membrane is ruptured the discharge might be from where?

Answer 9

otitis media rather than otitis externa

Question 10

if the canal become blocked by swelling or secretions what can be affected?

Answer 10

hearing

Question 11

what is the typical management for otitis externa?

Answer 11

topical aural toilet

Question 12

what is the treatment for moderate cases (e.g. occluded auditory canal) ?

Answer 12

ciprofloxacin + hydrocortisone ear drop

Question 13

what should be reserved for managing unresponsive or severe cases ?

Answer 13

topical clotrimazole if fungal

gentamicin drops if bacterial

More severe cases may require region systemic as well as topical antibiotics e.g. if cellulitis develops in the pinna or parotid region

Question 14

what should you use to manage eczematous otitis externa?

Answer 14

a steroid without antibiotic, as antibiotics may cause local sensitivity

Question 15

what is the general care advise for a patient with an otitis externa?

Answer 15

• Keep water out of the ear
• Avoid traumatising with e.g. cotton buds
• Keep hearing aids out as much as possible

Question 16

what might be required to carry drops past the swollen skin if external ear canal is very oedematous?

Answer 16

a wick or dressing

Question 17

if patients have had multiple courses of topical antibiotics the ‘friendly bacteria’ gets killed, this has what effect on the ear?

Answer 17

the friendly bacteria is protective against fungal infections so if killed, it can predispose people to develop fungal infections