otitis externa

Question 1

what

Answer 1

inflammation of skin in external ear canal

can be localised or diffusse
can spread to pinna

acute < 3wks
chronic > 3wks

Question 2

why is is sometimes called swimmers ear

Answer 2

exposure to water can lead to inflammation of ear canal

Question 3

what can be protective

Answer 3

ear wax

Question 4

inflammation can be caused by

Answer 4

bacteria
fungal
eczzema
seborrhoeic dermatitis
contact dermatitis

Question 5

when should consider fungal infection

Answer 5

patients that have had multiple courses of topical antibiotics

Question 6

most common bacterial causes

Answer 6

pseudomonas aeruginosa

staph a

Question 7

symptoms

Answer 7

ear pain
discharge
itchiness
conductive hearing loss

Question 8

OE

Answer 8

erythema and swelling ear canal
tenderness
pus or discharge
lymphadenopathy

Question 9

OE: tympanic membrane

Answer 9

may be obstructed by wax or discharge

may be red

if ruptured, discharge in ear canal might be from otitis media rather than otitis externa

Question 10

Mx - Mild

Answer 10

acetic acid 2% (earcalm OTC)

has antifungal + antibacterial effect

can also be used prophylactically before and after swimming

Question 11

Mx - moderate otitis externa

Answer 11

topical antibiotic and steroid

e.g. Otomize spray - neomycin, dexamethasone, acetic acid

Question 12

using topical aminoglycoside (gentamicin, neomycin)

Answer 12

need to exclude perforated TM as they are ototoxic if get past TM

Question 13

Mx - severe or systemic symptoms

Answer 13

oral antib e..g. flucloxacillin or clarithromycin

discussion with ENT, ?IVantib

Question 14

Mx - fungal infection

Answer 14

clotrimazole ear drops

Question 15

malignant otitis externa

Answer 15

severe and LT form otitis externa

infection spreads to bones surrounding ear canal and skull

progresses to temporal bone osteomyeltisi

Question 16

malignant otitis externa - risk factors

Answer 16

diabetes
immunosuppresive medication e.g. chemo
HIV

Question 17

malignant otitis externa - features

Answer 17

symptoms more sevre

persistent headache, pain, fever

Question 18

malignant otitis externa - indicated by

Answer 18

granulation tissue at junction between bone and cartilage in ear canal (~ 1/2 way along)

Question 19

malignant otitis externa - Mx

Answer 19

hosp admission by ENT
IV antib
CT or MRI to assess infection

Question 20

malignant otitis externa - complications

Answer 20

facial nerve damage/palsy 
other cranial N involvement
meningitis
intracranial thrombosis 
death