Otitis

Question 1

Primary factors of OE

Answer 1

systemic disease

- enough for inflammation (FB, allergy, autoimmune, endocrinopathy, parasitic)

Question 2

Parasites as primary factors of OE

Answer 2

1. otodectes cynotis (ear mite) nonburrowing obligate parasite
   *50% of OE in cats, 10% in dogs. feed on lymph and blood (especially <1 yr animals)
2. otobius megnini (spinous ear tick) more common in SW US/Large animal, larval infection
3. E. alfreddugesi (chiggers) seasonal(fall) see red/orange dots around ear canal
4. Demodex. in cats suspect FeLV, FIV, neoplasm.
5. Scabies (scabiei - dogs) usually isnt in the ear, associated with a lot of pruritis, thick crusts
   (notoedres cati - cats) face, pinna not in ear canal as much, also severe pruritis.

Question 3

one of most pruritic diseases

Answer 3

scabies

Question 4

Which parasite isn’t ruled out just because you can’t see it on the scrape?

Answer 4

scabies

Question 5

FB otitis

Answer 5

unilateral! with acute pain
(plant awns, insect, sand, dry meds)
remove and use topical abx

Question 6

intraluminal tumor causing otitis externa

Answer 6

relatively uncommon
ulceration and necrosis
often more malignant in cats than dogs (**ceruminous gland adenocarcinoma, squamous cell carcinoma, mast cell)

Question 7

Nasopharyngeal polyp

Answer 7

• etiology can be congenital, bacterial or calicivirus.
• chronic uni/bilateral otitis, mass in canal, head tilt
• tx with surgery

Question 8

apocrine cystomatosis

Answer 8

sitting on pinna, start small.

sx necessary because they will obstruct the canal

Question 9

atopic dermatitis and OE

Answer 9

red and inflamed

pinna, vertical canal, entire canal when chronic. 50% have bilateral

Question 10

____% of food allergy have OE

Answer 10

80%

Question 11

contact allergy and otitis externa

Answer 11

usually associated with topical meds (gentamycin, propylene glycol (in lots of ear products) )

Question 12

disorders of keratinization and OE

Answer 12

primary idiopathic seborrhea
hypothyroid
sex hormone imbalance
lipid related conditions

Question 13

primary idiopathic seborrhea

Answer 13

(cockers!!) excessive cerumen production often progresses to calcifying OE and OM

Question 14

endocrine disease and OE

Answer 14

(hypothyroid and sex hormone imbalance)

• inc. mucin in dermis and hyperplasia/hyperkeratosis epidermis
• chronic bilateral otitis +/- dermatitis, usually alopecia and scaling
• tx with hormones/sx

Question 15

autoimmune disease and OE

Answer 15

pemphigus

tip of pinna, generally not in the canal

Question 16

Juvenile cellulitis and OE

Answer 16

puppy strangles!

facial lesions and purulent otitis and facial ulcers…

Question 17

secondary factors for OE

Answer 17

basically infections
- bacteria and yeasts (same ones on skin)
Bacteria: staph**, psuedomonas, proteus, e. coli, klebsiella)
Yeast: malassezia (normally in ear), candida (rare) doesn’t usually affect the ear

Question 18

perpetuating factors of EO, cause otitis to persist

Answer 18

otitis media, mineralization, hyperplasia of canal

Question 19

pathogenic changes

Answer 19

hard to differentiate, get harder/calcified (v. squishable, needs to be imaged for confirmation)

Question 20

general clinical signs of OE we see

Answer 20

painful, red, edematous, pus

Question 21

clinical signs of OE

Answer 21

• *odor, head shaking, discharge**
• head tilt, pain
• (with chronicity) erythema, edema, lichenification, hyperpigmentation, excoriation, mineralization

Question 22

otitis media

Answer 22

extension of OE
(goes thru ear drum and sits there, rarely moves through eustacian tubes,)
- diagnosis difficult, can’t visualize tympanic membrane, very painful
- neurological signs - facial paralysis, horners syndrome (because of compression/inflammation)

Question 23

ear cytology

Answer 23

easy, mandatory and fundamental!!!

heat fix a swab

Question 24

video otoscopy

Answer 24

used to do a deep ear flushing, can visualize tympanic membrane
(also myringotomy artifical rupture of membrane)

Question 25

purulent discharge and meds?

Answer 25

discharge will inactivate meds like gentamycin, polymyxin B

Question 26

have to _____ if doing a deep ear flush

Answer 26

intubate! don’t want any nasties getting in the lungs

Question 27

do a culture and sensitivity for ___ not ___

Answer 27

OM not OE

Question 28

ceruminolytics

Answer 28

squalene or propylene
need to stay in 20 minutes and be flushed out
some are irritating and potentially toxic

Question 29

acidifying agents

Answer 29

dry the canal

dont use with aminoglycosides

Question 30

common antimicrobial agents

Answer 30

chlorhex
ketoconazole
hypochlorous acid

Question 31

most common antibiotics

Answer 31

aminoglycosides (neomycin, gentamycin)

Question 32

abx

Answer 32

aminoglycosides
fluoroquinolones(enrofloxacin)
polymyxin B
florfenicol (leave in a week)

Question 33

when to use systemic abx for otitis?

and then always?

Answer 33

OM!!
or sever OE (fluroquinolines, clyndamycin)
Always use with topical tx!!

Question 34

treat OM for minimum of

Answer 34

6-8 weeks

Question 35

often have contact allergy

Answer 35

neomycin, gentamycin

Question 36

otitis is not

so always?

Answer 36

a disease!!!

treat underlying disease