Diagnostic Tests in Dermatology Flashcards
what can a superficial skin scraping be used to diagnose?
scabies
notoedric mange
cheyletiellosis
dermatophytosis
Demodex gatoi
where should you take a skin scraping to diagnose scabies?
ear pinnae margins
elbows
hocks
where should you take skin scrapings for notoedric mange in a cat?
head
ear pinnae
neck
where should you take skin scrapings for demodicosis in a dog?
areas of spontaneous focal alopecia
pretty easy to find
where must the apple-green fluorescence be seen in a wood’s lamp test?
in the hair shafts
not on the scales
how can you differentiate self-induced from spontaneous alopecia?
self-induced: broken hairs
normal hair tips in spontaneous
what does cytology allow?
define type of inflammatory cells
define type of microbes
distinguish infection from contamination
when should you perform a bacterial culture?
if pyoderma does not respond to antibiotics
rods in cytology, especially intracellular
risk of antibiotic resistance
when should you perform a dermatophyte culture?
suspected dermatophytosis when direct trichoscopy is negative
identification of carriers
treatment control
identify species
are there any lab tests to confirm or rule out allergies?
no- clinical diagnosis
how can you diagnose a food allergy?
elimination diet with consequent re-challenge
what diseases need to be diagnosed with a biopsy?
most autoimmune diseases
most neoplastic diseases
many primary cornification disorders
what is a deep skin scraping used to diagnose?
demodex mites
not Demodex gatoi
how difficult is it to find the scabies mites?
40-50%
where should you take skin scrapings for notoedric mange?
head
ear pinnae
neck
easy to find
