Diagnostic aids Flashcards
1
Q
skin scraping
A
- need scalpel blade or spatula, mineral oil, microscope slide, cover slip
- place mineral oil on blade/spatula, add mineral oil to slide
- scrape until you get a small amount of blood, multiple scrapings
- cheyletiella, demodex, sarcoptes
2
Q
trichogram
A
- pluck hairs and look at them under a microscope
- examination of hair shaft
- feline self-inflicted alopecia, color dilution alopecia, dermatophytosis, telogen defluxion
3
Q
direct examination of hair and scales for dermatophytes
A
- hair collected more frequently than scales
- collect scales after plucking hairs
- pluck from within the lesion and towards the periphery
- may see spores, hyphae
4
Q
wood’s lamp examination
A
- not very sensitive (only 50% of microsporum canis will fluoresce)
- hair should be exposed to UV light for 3-5 min
- will fluoresce yellow/green if positive (scales, crusts, dermatophytes won’t)
5
Q
cytologic examination
A
direct smear, impression smear, swab smear, scraping, tape prep, FNA
6
Q
direct smear
A
- for fluid-containing lesions
- use tip of needle to collect material, smear on slide
7
Q
impression smear
A
- when lesion is moist/greasy or from under a crust
- slide pressed against site to be examined
8
Q
swab smear
A
- draining tracts or sinuses, ear canals, interdigital webs, dry crusty-surface lesions
- cotton-tipped applicator collects sample, rolled on surface of slide
9
Q
scrapings
A
- under crusts and for greasy skin surfaces
- goal is to remove stratum corneum
- gentle and superficial scrape, wipe on slide
10
Q
FNA
A
- nodules, tumors, cysts
- needle inserted, suction applied, redirected
- contents put onto slide
11
Q
tape cytology
A
- useful for diagnosing malassezia dermatitis
- apply tape to lesion with scale, press and scratch, use dark blue diff quik stain
12
Q
bacterial culture and sensitivity - when to use
A
- should be performed in all cases of deep pyoderma and any that aren’t responding to therapy
- patients that have been on lots of abx
- patients with a hx of drug resistant infections
13
Q
sampling superficial pyodermas
A
- clip and clean with alcohol
- rupture pustule with needle
- force exudate out, swab it
14
Q
sampling deep pyoderma with draining tracts
A
- clip and clean with alcohol
- apply pressure to deepest layers to force exudate to surface
- touch sterile swab to it, streak
15
Q
punch biopsy for deep pyoderma with ulcerated skin
A
- clean with soap then alcohol
- use 2 or 4mm punch biopsy to obtain full thickness sample
- remove epidermis from sample
