Derm Part 3 - Fundamentals, Parasites & Ears Flashcards
what causes flea bite hypersensitivity?
flea saliva
treatment for fleas?
isoxazolines
98% fleas killed within 24 hours
can you kill a tick population?
no not local
treatment of ticks
isoxazolines
90% ticks killed within 48 hours
what is the purpose to treating ticks
preventing disease transmission
what ectoparasite is the cause of the most pruritic dog disease?
sarcoptes scabei canis “scabies/mange”
what mite has the distribution of elbow, distal limbs and pinna
sarcoptes
diagnosis of sarcoptes
superficial skin scrape
pinnal-pedal reflex
treatment for sarcoptes
isoxazolines - treat for 8 weeks
what mite causes “walking dandruff”
Cheyletiellosis
NOT species specific
what mite has a dorsal distribution and is scaly
Cheyletiellosis
Cheyletiellosis diagnosis
superficial scrape
tape
flea comb
Cheyletiellosis treatment
Isoxazolines for 8 weeks
is demodex a parasite?
no - commensal organism, disease of immunosuppression and overgrowth
which demodex species is contagious
D. gatoi in cats
what are the two different forms of demodex in the dog? differences?
juvenile due to age - localized or generalized
adult due to immunocompromise of some sort - generalized only
a dog with alopecia around the eyes, comedones and lesions on the paws, what ectoparasite do you suspect?
demodex
demodex diagnosis
deep skin scrape
trichogram
tape w/ squeezie
demodex treatment
Isoxazolines
are lice species specific?
yes
primary derm lesions
macule
patch
nodule
papule
pustule
vesicles/bulla
comedones
plaque
diagnostic for macules/patches to see if its inflammatory or hemorrhage/vasculitis
diascopy - press slide
inflam = blanches
hemorrhage = stays
follicular casts typically associated with what disease
sebaceous adenitis
difference between erosion and ulcer?
erosion - partial absence of epidermis, partial thickness
ulcer - complete absence of epidermis, full thickness
hypopigmentation most often due to what 2 things
allergic dermatitis
immune mediated disease
what is the difference in microscope set up for parasites vs cells, yeast, bacteria
parasites - condenser lowered and 5-10x
cells, yeast, bacteria - condenser raised, 100x, oil
how large should punch biopsy be?
6-8mm
what should you NOT biopsy?
ulcers – unless its pemphigus vulgaris then do junctional biopsy
primary cause of otitis externa
allergy which causes inflam which causes infection
4 causes of otitis externa
allergy
foreign body
endocrinopathy
immune disease
when should you culture an ear cytology?
if rods are seen e.g. Pseudomonas
how long to treat otitis externa
3 weeks
topical therapy (antibacterial, steroids or antifungal)
how long to treat otitis interna/media
8 weeks
systemic therapies
what drugs most commonly cause ototoxicity? what is the most common type of ototoxicity?
gentamicin, chlorhexidine
cochlear (loss of hearing)
what is the problem with chronic otitis externa? how can you treat?
anatomy
open ears with steroids
resolve infection
prevent - weekly/monthly maintenance
most common cause of otitis media
chronic upper resp disease
signs of otitis media
horners syndrome
facial n paralysis
xeromycteria
signs of otitis interna
neuro signs
most common cause of otitis media/interna
abnormal drainage from auditory tube
treatment of otitis media/interna
systemic preferred
culture middle ear
treat for 8 weeks
treatment for feline aural polyps
traction/avulsion + steroids (95% success rate)
