7. Ear diseases - Otitis externa, media, interna Flashcards
What is otitis externa?
Inflammation of the external ear canal
What is the first to rule out in case of otitis externa?
Presence of parasites - Otodectes cynotis mainly
Mites!!!
What can be the cause for development of otitis externa and important to rule out as an underlying cause?
- Parasites - Otodectes cynotis, Notoedres, Sarcoptes scabiei
- Allergies - Atopy, food hypersensitivity, contact allergy
- Autoimmune disorder - Pemphigus
- Endocrinopathies - hypothryeosis, hyperstrogonism
- Idiopathic seborrhea - cocker spaniel
- Foreign body - grass
- Bacteria - Staph. pseudointermedium, Proteus mirabilis, P. aeruginosa
- Yeast - Malassezia pachydermatis
Clinical signs of otitis externa
- Headshaking, scratching or rubbing ears (pruritus)
- Odour
- Pain on manipulation of the ear
- Exudate, redness and edema of external ear canal.
Exudate caused by otodectes cynotis is shown in cats as:
Exudate usually black, dry, crusty, debris in the ear
Exudate caused by otodectes cynotis is shown in dogs as:
Exudate is blackish and more moist
How can otitis externa be diagnosed?
According to history and clinical examination, then can do further
- Otoscopy
- Skin scraping
- Cytology: Cultivation to determine bacteria present
- Radiograph
- Biopsy
Otitis externa exudate appearance in case of parasites?
Dark, dry cerumen
Otitis externa exudate appearance in case of bacteria?
Moist, yellow, odorous
Otitis externa exudate appearance in case of yeast?
Brown, waxy, acidic
Otitis externa exudate appearance in case of keratinization disorder?
Yellow, oily cerumen
In case of chronic otitis with an edematous ear flap, where it is difficult to evaluate ear canal, what to do?
If ear drum breaks?
- Give anti-inflammatory to decrease edema.
- After a few days otoscopy/endoscopy possible to use w/o anesthesia if very painful.
In case of broken ear drum: Do not apply drug –> ototoxic!
- Give oral ATB
Which bacteria is most common for causing long term otitis?
Pseudomonas aeruginosa
How can otitis be treated?
Se notes för mer förklaring-
- Number one thing is CLEAN (chorhexidine) or if suspected ear drum rupture - saline flusing
- Cerumenolytics
- Keratinolytic
- Drying solutions - careful in ulcerations of ear canal
- Glucocorticoids
- Antiparasitic
- ATB
- Topical antifungal agents - If caused by Malassezia or Candida
- Systemic therapy - Short acting corticosteroids (Prednisone) used for ruptured ear drum
In case of ulcerations - Ivermectin
What is otitis media?
Inflammation within the middle ear.
Affects ear drum, auditory and eusthachian tube, auditory ossicles and tympanic nerve, continuation from OE
What is etiology of otitis media?
In dogs - often secondary to otitis externa as a chronic process
In cats - mostly due to bacterial or virus infections of upper airways
What does a blue colored pathological ear drum mean?
Intratympanic bleeding
What does a red colored pathological ear drum mean?
Acute otitis media
What does a white colored pathological ear drum mean?
Pus
What does an amber colored pathological ear drum mean?
Serous exudate
How does pathology of ear drum looks like?
Dull, turbid
Should be concave, transparent, grey, lustrously
What are clinical signs of otitis media?
Similar to otitis externa since its a chronic development
- transmission of pharyngeal infection
- hematogenous infection
- salivation
- Absent palpebral reflex
- Horner syndrome –> ipsilateral miosis, ptosis, enopthalamus
- Keratitis sicca
What is otitis interna?
Inflammation within the inner ear.
Affecting cochlear, vestibular and semicircular apparatus.
Generally results from otitis media
What is reason for development of otitis interna?
- Left untreated otitis media
- Tumors
What are clinical signs of otitis interna?
Typically neurological signs:
- Head tilt
- Circling
- Horizontal or rotational nystagmus
- Vomitus
- Ataxia
- Deafness if bilateral affection
More common with more general neurological signs
