Exam 2 - Otitis Externa Flashcards
what is cerumen?
waxy secretion formed by sebaceous & ceruminous glands that contains immunoglobulins, & coats the epithelial lining trapping debris/desquamated cells/hair/micro-organisms
T/F: otitis is a form of skin disease & may be the only sign of dermatological disease going on in an animal
true
what is the most common reason we see otitis media?
extension of chronic otitis externa into the bulla/tympanic cavity
how is otic disease classified?
anatomical classification
what is otitis externa?
external vertical and/or horizontal canal that is inflammed/diseased
what are some signs that indicate otitis externa?
otic odor, head shaking/pawing/rubbing at ear, altered ear carriage, ipsilateral head tilt that isn’t neurologic, otic discharge, aural hematomas, etc
what is otitis media?
media - middle ear (bulla) is inflammed/diseased
what are some notable exceptions of when we see otitis media in companion animals?
feline inflammatory polyps originating in the bulla or eustachian tube
primary secretory otitis media in cavalier king charles spaniels
what is otitis interna?
inner ear is inflamed/diseased
what is the most common reason we see otitis interna in companion animals?
most often due to the extension of otitis media into the inner ear structures within the petrous temporal bone of the skull
extension of otitis media into otitis interna is a very common cause of what neurological disease?
peripheral vestibular disease
what is a primary cause of otitis externa in companion animals?
companion animal food reaction/allergy
what are some clinical signs seen in animals with otitis media/interna?
otitis externa signs, head & neck pain, difficulty opening the mouth, horner’s syndrome, facial nerve paralysis, peripheral vestibular disease, & deafness
what are some pathological changes seen in the ear due to chronic otitis externa?
edema, glandular hyperplasia, folding, stenosis, fibrosis, calcification, & failure of epithelial migration
what are some examples of primary causes of otitis externa?
parasites, allergy, cornification, endocrine problems, immune-mediated/autoimmune disease, trauma, FB, & mass
what are some predisposing factors that contribute to otitis externa?
animal conformation, excess moisture, iatrogenic, & owner error
what are some sequela of otitis externa?
infection, ongoing pathology, & otitis media
what therapy can be utilized to reduce predisposing risk factors for otitis externa?
reduce moisture in the ears, reduce cerumen, remove hair, reassess owner compliance, & reassess your treatment plan
what therapy can be utilized to reduce primary causes for otitis externa?
often neglected part of therapy - failure to ID & treat a primary cause is a common reason for failure, need to ID & treat the cause
therapy is more than just a topical commercial product
what therapy can be utilized to reduce the common sequela of otitis externa?
remove otic discharge, improve drainage of the ear, ID & eliminate infection, & halt the progression of the disease
before treating otitis externa in cats, what must be ruled out first?
otodectes
what is the purpose of using systemic glucocorticoids for an animal with otitis externa?
reduce pain, edema, cerumen, hyperplasia
& improve visualization & flushing
at what point would TECABO be recommended for a patient with otic disease?
animal has:
ossified canals
stenosis in the canal is unaffected by steroids
patient intolerance to other therapies/owner can’t effectively treat the pet
monetary concern over time
patients with otitis media/interna
what are some dog breeds that have normally narrowed ear canals making them predisposed to developing otitis externa?
shar pei, chow chow, & english bull dog
why does poor confirmation predispose an animal to otitis externa?
they have poor aeration of the canal, increased temperature in the ear, & increased humidity in the canal
why does increased moisture in the ear predispose an animal to otitis externa?
maceration of the epithelium & excessive moisture removes the protective cerumen
what are some examples of iatrogenic/owner errors that may predispose an animal to otitis externa?
inappropriate treatment, excessive ear flushing, over or under treating, & trauma from cotton swabs
removing healthy cerumen, infection is gone but owner continues treatment
what is the most common cause of otitis externa in cats?
otodectes cynotis - ear mites
what is an example of an endocrinopathy that causes otitis externa?
hypothyroidism - ceruminous otitis
what mass commonly causes otitis externa in cats?
inflammatory polyp - usually unilateral otitis where the mass arises from the bulla, eustachian tube, or nasopharynx
what is primary secretory otitis media?
disease seen in cavies where excessive mucus production in the bulla can rupture through the tympanic membrane & drain into the ear canal with many signs overlapping with chiari-like malformation & syringomyelia
what cocci are commonly involved in otitis externa?
staph, strep, & enterococcus
what rods are commonly involved in otitis externa?
pseudomonas, proteus, e. coli, & cornyebacterium
what yeast is commonly identified in otitis externa?
malassezia
what is the treatment for end-stage otitis?
canal removal
T/F: at least 70% of the time in otitis media, the tympanum is intact
true
what is likely present if an animal has had otitis externa for more than 6 months?
otitis media
what pathological feature is seen that indicates acute inflammation in the ear canal?
edema
what pathological feature is seen that indicates chronic inflammation in the ear canal?
glandular hyperplasia, stenosis, & folding
what is a ceruminolith?
solid accumulation of cerumen - wax plug/ball
if bloody discharge is seen in an ear canal, what is likely present?
an otic mass
what kind of otic discharge may indicate over treatment?
white, creamy, odor-free discharge
what is otoscopy used for?
to visualize the health of the otic canal & look for pathology
what treatment can you do for an animal that has severely inflamed/proliferative ears to help you better visualize the canal & treat their discomfort?
7-14 days of anti-inflammatory dose of oral steroids or topical steroids to reduce pain, edema, & glandular secretions to then be able to properly visualize the ear canal
if you see that the tympanic membrane looks ruptured/bulging/thickened/absent, what are you concerned for the presence of?
otitis media
what does cerumen discharge look like?
gray to brown/black material that is adhered to the canal wall that may be dry or moist & has a yeasty odor
when may you use a video otoscope?
performing a myringotomy for a ruptured tympanum, collecting bulla contents, flushing the bulla, & getting a of biopsy any mass
what are the goals of otic cytology?
identifying/characterizing an infection & perpetuators of disease & better assisting in therapeutic intervention selection
if you see rods on an ear cytology, what agent do you think is present?
pseudomonas
what is the most common agent seen in yeast infections in the ears?
malassezia pachydermatitis
T/F: it is normal to find inflammatory cells in a normal ear canal
false
T/F: an otic culture is very helpful in diagnosing otic disease
false - rarely adds to any info obtained through otoscopy & otic canal cytology
______ ________ is an indication for bulla culture
otitis media
T/F: topical antibiotics can achieve a much higher concentration in the ear canal
true
what happens if you fail to identify & treat the primary cause of otitis externa?
lead to more frequent/chronic & resistant infections & continuing pathological changes in the ear canal resulting in an end-stage ear that is beyond medical intervention
for all cases of chronic/proliferative otitis & otitis media, what therapy is recommended in the hospital?
deep otic flushing under general anesthesia - collect bulla contents for culture prior to aggressive cleaning measures
what is always safe to use in flushing out an ear? when would you use it?
warm saline!
worried about tympanum/otic toxicity
what drug can be used in the hospital for breaking up wax in the ear canal?
dioctyl sulfosuccinate (surfactant) must flush out well
why should you be careful with how much pressure you apply when flushing an ear?
too much pressure can rupture the tympanic membrane
what is considered to be a ‘liquid q-tip’ for at home treatment?
ear flush
how should you show the client to use the proper amount of flush at home? how often do you instruct them to use it?
fill up the canal with otic flush - let them see it
don’t use more frequently than every 48 hours during initial therapy & use prophylactically after that
T/F: any product/ingredient has the potential to be ototoxic & may manifest as an idiosyncratic reaction for any given patient
true
how should you show the owner to properly dispense medications into the ear?
place a thin volume of medication to where it lines the canal & treat twice daily
ototoxicity is reported most commonly with what drug class?
aminoglycosides
how long should topical treatment be prescribed for otitis externa?
2 weeks & then reassess clinically & cytologically - need to continue 1-2 weeks past clinical & cytological resolution
what are the benefits of using systemic steroids for a patient with otitis externa?
reduce pain - allows client to instill topicals
reduce edema - allows for better topical penetration & reduces humidity
reduces cerumen production - less debris inactivating topicals
reduce glandular & epithelial hyperplasia - slows the progression of pathological changes & dilates the canal
when should you consider prescribing systemic steroids for a patient with otitis externa?
otic canals are too painful/proliferative to assess
topical drugs are ineffective or deemed inappropriate
when trying to assess if proliferation/stenosis are reversible & therefore amenable to continue medical management
if steroids don’t open the canal, total ear canal ablation & bulla osteotomy is likely indicated
what diagnostic tool should you use on every case of otitis?
cytology
T/F: often, enough volume of topical products are not administered in the otic canal
true
why do we see animals needing TECABO?
many cases of otitis are needlessly/unsuccessfully managed medically & lead to the continued pain/discomfort to the patient & inappropriate cost to the client
what are the goals of managing an ear with otitis at home?
dry, acidify, neutralize, antiseptic, & remove cerumen
what cases do you reserve otic canal culture for?
when you see neutrophils cytologically & appropriate empirical therapy fails
T/F: pseudomonas species are becoming increasingly resistant to fluoroquinolones
true
are topicals going to work well in a patient that has ongoing canal pathology due to otitis externa?
nope
what is the most common benign neoplasia seen in the ears of dogs?
ceruminous adenoma
what is the most common malignant neoplasia seen in the ears of cats?
ceruminous adenocarcinoma & SCC
what dog breeds are predisposed to cornification defects leading to ceruminous otitis?
cocker spaniels!!!!!!
T/F: canine allergic food reactions & atopy are common allergic disorders that cause otitis
true
what does a ‘predisposing factor for otitis externa’ mean?
in & of themselves not able to cause otitis but make an individual more susceptible to otitis when a primary cause arises
what does it mean to be a ‘primary cause’ of otitis externa?
conditions/diseases that result directly in otitis
what does it mean to be ‘perpetuating sequelae of otitis externa’?
secondary conditions resulting from primary causes that contribute to disease progression & hinder resolution even if the primary cause & predisposing factors have been managed or resolved
what are the canals that make up the companion animal’s ear?
vertical canal & horizontal canal
why we don’t use q-tips & instead use flush to avoid pushing gunk further into the ear
what is the function of the ear canal?
directs sound waves to the tympanic membrane
what are the 2 parts that make up the tympanic membrane?
pars tensa & parsa flaccida
what is the pars tensa?
thin semitransparent membrane continuous with the otic canal lining on the lateral side & bulla lining on the medial side
what is the pars flaccida?
dorsal opaque rim of the ear drum with well-vascularized tissue - don’t confuse with it being a mass
what is the function of the pars tensa & pars flaccida?
tensa - transmits sound waves to the auditory ossicles
flaccida - provides bloody supply to the tensa
what is inside of the tympanic cavity?
auditory ossicles (malleus, incus, stapes), eustachian tube, & nerves)
disruption of postganglionic sympathetic fibers leads to horner’s syndrome
the tympanic cavity is lined with upper respiratory epithelium (ciliated columnar epithelium) - do feline respiratory viruses cause or favor inflammatory polyps?
favor - may play a role in the development of them by triggering inflammation
what is the function of the tympanic cavity/bullae?
transmit sound vibrations through auditory ossicles to the oval/vestibular window of the inner ear
what is included in the inner ear?
cochlea & semicircular canals
vestibule is the common entrance into the cochlea & semicircular canals
what is the function of the inner ear?
cochlea - hearing
semicircular canals - balance
in regards to otic anatomy, what is the manubrium? why is it important?
manubrium of the malleus inserts within the pars tensa & is visible on the otoscope as a finger-like projection
it is the region that contains germinal cells of the tympanum, so if it is ruptured, this is what allows for healing to occur
what is epithelial migration?
normal cleaning process of the ear - pulling out squames, cerumen, hair, microbes, & medication
germinal center cells of the pars tensa migrate outwards & travel up & out of the ear
what are some examples of in-hospital topical cleaners used for otitis externa?
bulb syringe/water pick/catheter & syring
dioctyl sodium sulfosuccinate
what are some examples of at-home topical cleaners used for otitis externa?
cerumenolytics, pH adjusters, antimicrobials, & otic barrier repair
what active ingredient would you prescribe if you saw cocci bacteria on cytology of an ear?
a. gentamicin
b. neomycin
c. florfenicol
d. ssd
e. polymixin b
what active ingredient would you prescribe if you saw rod bacteria on cytology of an ear?
a. gentamicin
b. neomycin
c. enrofloxacin
d. orbifloxacin
e. ssd
f. polymixin b
what active ingredient would you prescribe if you saw yeast organisms on cytology of an ear?
a. miconazole
b. clotrimazole
c. posaconazole
d. terbinafine
what pathology is seen in the photo?
glandular hyperplasia
