Introduction to dermatology Flashcards Preview

RUSVM small animal medicine 2 > Introduction to dermatology > Flashcards

Flashcards in Introduction to dermatology Deck (46)
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1
Q

layers of the skin

A

epidermis, dermis, and hypodermis (SQ)

2
Q

layers of the epidermis

A

stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, stratum basale

3
Q

parts of a complete dermatological exam

A
good lighting and magnification
assess the skin- haired and non haired
identify lesions- primary vs secondary
which body sites are involved- lesions and distribution
dermogram
4
Q

primary lesions

A

initial eruption that develops spontaneously as a direct reflection of the underlying disease
appear and disappear quickly

5
Q

secondary lesions

A

evolve from primary lesions or are artifacts induced by the patients or by external factors such as trauma/biting/licking/medication
usually stay around for a much longer time period

6
Q

types of primary lesions

A
macule
patch
papule
plaque
vesicle
bulla
wheal
nodule
tumor
cyst
7
Q

types of primary or secondary lesions

A
alopecia
scale
crust
follicular casts
comedone
pigmentary abnormalities
8
Q

types of secondary lesions

A
epidermal collarette
scar
excoriation
erosion
ulcer
fissure
lichenification
callus
9
Q

macule

A

flat spot less than 1 cm on skin with change in skin color

10
Q

patch

A

macule greater than 1cm

11
Q

purpura, petechia, ecchymoses

A

type of macule caused by bleeding into the skin

12
Q

papule

A

small, solid elevation in skin up to 1cm in diameter

13
Q

plaque

A

coalition of papules forming flat topped elevation

14
Q

pustule

A

small elevation of epidermis filled with pus

15
Q

vesicle

A

elevation of epidermis filled with clear fluid

16
Q

bulla

A

vesicle greater than 1cm in diameter

17
Q

wheal

A

sharply delineated lesion of edama

18
Q

nodule

A

solid raised palpable lesion greater than 1cm, can include abscess

19
Q

tumor

A

large palpable mass- neoplastic enlargement

20
Q

cyst

A

epithelial lined cavity with solid or fluid material

21
Q

alopecia

A

absence of hair from area where it is normally present

22
Q

scale

A

accumulation of loose fragments of horny layer of skin

23
Q

crust

A

accumulation of dried serum, exudate on surface of skin

24
Q

follicular casts

A

accumulation of keratin and sebaceous material stuck to a hair shaft

25
Q

comedone

A

dilated hair follicle filled with debris

26
Q

epidermal collarette

A

scale arranged in circular pattern. associated with pustule, vesicle, or bullae

27
Q

scar

A

fibrous tissue has been replaced the damaged dermis or sq tissue

28
Q

excoriation

A

linear abrasion of the skin

29
Q

erosion

A

shallow ulcer that does not break basal layer

30
Q

ulcer

A

break in epidermis with exposure of dermis

31
Q

fissure

A

linear cleavage in the epidermis or dermis caused by disease or injury

32
Q

lichenification

A

thickening and hardening of the skin

33
Q

callus

A

a localized hyperplasia of the stratum corneum of the epidermis caused by pressure or friction. elbows and lateral hock areas are common sites for callus formation in the dog

34
Q

superficial skin scrape

A

surface mites: sarcoptes, notoedres, otodectes, cheyletiella, demodex gatoi
moisten blade with liquid paraffin or KOH or mineral oil
scrape a large area because mites are fewer in number
if negative, does not rule out superficial mites

35
Q

deep skin scrape

A

follicular parasites, mostly demodex
scrape small focal area with dulled blade using mineral oil
induce capillary hemorrhage
squeeze follicles
if negative, may not rule out follicular parasite
scrape multiple affected areas
put on glass side, 10x and lower condenser

36
Q

anagen hair

A

ball or balloon

37
Q

telogen hair

A

arrow head

38
Q

tape impression smear

A

place scotch tape onto microscope slide after on skin

1 drop of #3 diff quick to slide

39
Q

FNA technique

A

21-23 gauge needle
attached to 5ml syringe
put needle in lesion; aspirate; pull needle back and redirect into another site; aspirate
release pressure on needle before withdrawing
disconnect needle from syringe; add few mls of air to syringe and reattach needle
express contents in needle on to microscope slide

40
Q

woods lamp

A

50% of m. canis strains will fluoresce
turn on lamp 5-10 minutes prior to use
false positives: keratin scale, soaps, dyes, and some medications

41
Q

fungal culture

A

if hair shafts fluoresce via woods lamp, pluck those for innuculation. if nothing fluoresces, use sterile toothbrush technique
DTM- color changes occur, must look at every day
dermatophyte used protein in the media resulting in alkaline by products which turn media red at the same time dermatophyte colony appears. must check daily because non pathogenic fungi will use the protein source once carbohydrates are exhausted, but this type of colony would be present for days before the color change

42
Q

skin biopsy indications

A

nodules/tumors, ulcers/vesicles, severe acute generalized disease, mucosal lesions, footpad lesions, lesions unresponsive to normal therapy

43
Q

skin biopsy protocol

A
no prep, no scrub
do not disturb lesion
gently clip hair
handle sample as little as possible
place into formalin and culture pot
can use punch, wedge, excisional, or amputation
44
Q

bacterial culture and sensitivity

A

not indicated in all cases of bacterial pyodermas
indications: cytology shows cocci and rods or just rods, cocci but no response to correct antibiotic administered correctly, deep pyoderma, chronic AB/GC therapy, GSD pyoderma
sample techniques: swab, swab with surface prep, biopsy

45
Q

allergy testing serology

A

rely on antigen specific antibody levels
no vet outlay, quick, no sedation or clipping required
no positive control, only detects circulating IgE, lab variations, false positives, grouped allergens, some false negatives
NOT reliable for food allergens

46
Q

intradermal allergy testing

A

gold standard for identifying environmental allergens