Examination of the Skin + General Skin knowledge Flashcards
What are the functions of the skin
protection from external damage resistance to sheer stress barrier sensation metabolic - vit D synthesis
what are the 3 layers of the skin - superficial to deep
epidermis
dermis
hypodermis/subcutis
whats in the epidermis
stratified squamous epithelium
keratinised
whats in the dermis
dense irregular connective tissue
what separates the dermis and epidermis
basement membrane
what is the dermis split into
papillary - top
reticular - bottom
what is in the papillary dermis
most nerve endings
whats in the hypodermis/subcutis
adipose tissue
blood supply
what are the 5 layers of the epidermis bottom to top
stratum basale stratum spunosum stratum granulosum stratum lucidum stratum corneum
what types of cells are in skin
keratinocytes (95%) melanocytes Langerhans cells Merkel cells basement membrane
what do keratinocytes do
produce keratin
what do melanocytes do
pigment cells with melanin which scatters UV light
where are most melanocytes found
in stratum basale
what do Merkel cells do
neuroendocrine functions
where are merkel cells found
stratum basale
many are in touch areas
what is the basement membrane
sheet of matrix at interface of parenchyme + support tissue
whats the basement membrane made from
type 4 collagen, glycoproteins and glucosaminoglycacides
how do you describe a rash
DCM criteria
distribution (extensor/flexor/symetrical)
configuration (annular, clustered, linear, none)
morphology (maculae/papules etc)
what are bullae
blisters >5cm
what is a cyst
papule/nodule lined by epithelium ocntaining fluid, pus or keratin
what is ecchymosis
extraversion of blood into the skin
what is a macule
flat area of colour change
what is a nodule
palpable mass >0.5cm
what is a papule
palpable mass <0.5cm
what are petechiae
pinhead sized non blanching macules of blood due to small vessel haemorrhage
what is a plaque
flat topped palpable lesion
what is purpura
large non-blanching macules in the skin
what is a pustule
visible accumulation of pus in the skin
what is telangiectasia
visiblae dilation of small cutaneous blood vessels
what is an ulcer
any skin break, generally complete loss of epidermis
what is a vesicle
<5mm papule filled with liquid
what is a wheal
smooth surfaced dermal swelling, dermal oedema, non scaling
puncturing does not leak fluid
