Small Animal Dermatology, 3rd edition

548 DISEASES/DISORDERS

 Note findings (e.g., type of organisms; cells present) in the record; rank the number

of organisms and cell types present on a standardized scale (e.g., 0 to 4) to allow

treatment monitoring:

Bacteria: cocci –Staphylococcus(clusters or pairs),StreptococcusorEnterococcus

(small, chains); rods –Pseudomonas(long, narrow) orProteus(short, bipolar)

Yeast:Malassezia(broad-based budding, “peanut-shaped”) orCandida(narrow-

based budding)

Neutrophils: absence associated with colonization of the canal with bacteria or

yeast or mild infection; increased numbers especially with degenerate changes

and intracellular organisms indicates active response to infection

Red blood cells: associated with ulceration of the epithelial lining; often associ-

ated withPseudomonasspp.

THERAPEUTICS

 Diet: no restrictions unless a cutaneous adverse reaction to food is suspected.

 Client education: instruct clients, by demonstration, in the proper method for clean-

ing and medicating ears (especially the volume of medication to instill; average exter-

nal ear canal volume is 2.7 mL; there are 15–20 drops/mL).

 Surgical considerations:
Indicated when the canal is severely stenotic or obstructed, or when neoplasia

or a polyp is diagnosed

Severe, unresponsive otitis media may require a bullae osteotomy

Lateral ear resection or total ear ablation required with obstructed canals or neo-

plasia.

 Chronic otitis externa frequently leads to ruptured tympanae and otitis media.

 Complications following external ear flushing in cats (vestibular signs) are not

uncommon; clients should be warned of possible residual effects.

 Corticosteroid use is controversial with otitis media/interna.

 Avoid vigorous flushing of the ear with otitis media/interna.

 Osteomyelitis of petrous temporal bone and bulla may require 6–8 weeks of antibi-

otics.

 Uncontrolled otitis externa and media, as well as treatment complications, can lead

to deafness, vestibular disease, cellulitis, facial nerve paralysis, progression to otitis

interna, and, rarely, meningoencephalitis.

 Vestibular signs usually improve within 2–6 weeks.

 Tympanum integrity should be assessed prior to introduction of solutions and/or

medications into the external ear canal.

 Ear cleanser ingredients:
Tympanum not intact:

Saline solution

2.5% acetic acid (1:1 vinegar/water) rinses; acetic acid solutions may be

irritating if not buffered

2% N-acetyl-L-cysteine (NAC) solutions when biofilms suspected