DERMATOLOGY 1 Flashcards
what are 3 cell types in the epidermis
-keratinocytes
-melanocytes
-langerhans cells
what is the main cell in the epidermis
keratinocyte
what are the steps to keratinocyte production?
how long does this process take?
how to differentiate melaocytes form bacteria on stain?
bacteria: always blue on stain. more disorganised. smaller
during Increased cell infiltration in inflammation, which layer of skin do these cells go to?
dermis, which is connective tissue
what r these?
macromelanosomes
skin scrapes must go down until we see capillary ooze. why si this?
bc there is no blood supply in the dermis
what are 4 epidermal apengades/adnexae
- Simple versus compound follicles
– Hair follicle units - Arrector pili muscles
- Sebaceous glands
- Sweat glands
[the bulbs look different in anagen and telogen!]
in animals, which hair phase lasts the longest?
telogen
[except in non-shedding constant hair growing breeds such as poodles etc]
which phase of hair growth is vulnerable to chemotherapy?
anagen
what si the different between priritus & mutilation in TISSUE presesntation?
mutilation: affects subcutaneous tissue as well ,not just skin.
describe symmetrical alopecia
lesion in the same spot, not necessarily same shape
inflammatory alopecia
_____alopecia is normal to inflammatory
______ alopecia is normal to atrophic
[multifocal vs symmetric]
multifocal
symmetrical
scaling is the accumalation of what cells?
which is more common: primary or secondary?
karatinocytes
secondary
what is lichenification
thickening of skin
Hyperkeratosis is thickening of which layer of skin?
what abt acanthosis?
stratum corneum
acanthosis=epidermis
hyperkeratinosis:
orthokeratotic hyperkeratosis:
parakeratotic hyperkeratosis:
hyperkeratosis: scaling
orthokeratotic hyperkeratosis: increase in non-nucleated keratinocytes
parakeratotic hyperkeratosis: thickened SC with nucleated keratinocytes
what is lichenification?
thickening of the skin
whats this? [the cracks]
what is seborrhoea?
greasy accumulation of sebum & exudate
what is the differnet btwn a papula, plaque, and nodule?
papule <1cm
nodule >1cm
plaque-flat topped
what is a wheal?
accumalation of fluid within skin. dermal oedema
what si a cyst?
- Epithelial lined cavity with fluid or semi-fluid material
what is the difference in a pustule and a vesicle?
pustule: pus-filled
vesicle: fluid-filled
epidermal collarette is [nearly] pathognomonic for what?
exfoliative staphylococcal pyoderma
what are crusts?
dried exudate: blood, serum, pus
difference btwn eorsion and ulcer?
erosion: basement membrane intact
ulcer: basement membrane lost
what is the different btwn sinus and fistula?
fistula: connects epithelial lined compartments
sinus: connects soemthing else
What is erythema?
2 types/patterns?
how can you differentiate it from haemorrhage?
erythema is redness of skin due to increased blood flow
diffuse & macular-papular
can be differentiation by blanching: turns white temporarily when pressed. haemorrhage does not blanch
PIGMENT CHANGES
what is a comedome?
dialated hair follicle plugged with debris
[blackhead]
multifocal alopecia, comedome, and follicular casts. whats the diagnosis?
demodex DOUBLE CHECK
what are follicular casts
tight accumalations of scale around hair shaft
what are paintbrush lesions
Thick accumulations of crust across hair shafts
btwn dermatophilus and demodex, which shows paintbrush lesions? which shows follicular casts?
dermatophilus: paintbrush lesions
demodex: follicular casts
what is calcinosis cutis?
pathognomonic for what?
hyperadrenocorticism
