Clinical Skin Vi Flashcards
what is the normal cell turnover?
2-4 weeks
what are the 2 types of wound healing?
epidermal wound healing
deep wound healing
what is epidermal wound healing?
follows wounds that affect only the epidermis
involves basal cells of epidermis - check out slide
what is deep wound healing?
follows wounds that penetrate the dermis
What are the phases of deep wound healing?
inflammatory phase
migratory phase
proliferative phase
maturation phase
what phase is granulation tissue found?
migratory phase
whats a hypertrophic scar?
scar is raised, but within the original wound boundary
what is a keloid scar?
excess of the boundary extending into surrounding tissue
what is hyperkeratosis?
hyperplasia of the horny layer of the skin (or the cornea)
what is parakeratosis?
retention of nuclei in the stratum corneum of the skin
what is acantholysis?
loss of intercellular connections resulting in the loss of cohesion between keratinocytes
what is acanthosis?
epidermal hyperplasia (stratum spinosum)
what is a complement system?
group of proteins that effect lysis of cells and Ag-Ab complexes and cytokine release
what is psoriasis?
autoimmune t cell involvement (cytokines)
disease due to increase rate of proliferation of the mitotic cells = thick epidermis
abnormal keratinocyte differentiation - loss of S. granulosum
S. corneum is thick with nuclei retained
weak junctional complexes (silvery scales)
what is psoriasis lead to?
shedding of epidermis constantly resulting in scales seen as whiteish patches
how long is the epidermal turnover rate with psoriasis?
3-5 days
what is the histopathogenesis of bullous pemphigoid?
presence of igG antibodies specific to hemidesmosomes - separation of teh epithelium from the dermis
what releases proteases that degrade hemidesmosomes?
eosinophils
what is pempighus vulgarism?
rare autoimmune disorder affecting epidermis and mucosal epithelium - antibodies target desmosomes - cadherins and desmoplakins
desmosomes (intercellular bridges) messed up
separation of epidermal cells (S. spinosum) from one another
atrophy of prickle cell layer
blister formation - easy to rupture
what are the two types of albinism?
ocular
oculocutaneous
where is melanin in keratinocytes?
supranuclear
what are complications of long term albinism?
skin cancer
reduced visual acuity/photophobia (macular hypoplasia)
social stigma
what is vitiligo?
depigmentation disorder
autoimmune
destruction of melanocytes
what are the types of vitiligo?
focal, segmental, generalized
what is carcinoma?
cancer arising from epithelial cells
what is the histogenesis of sqamous cell carcinoma?
malignant tumor of keratinocytes
exposure to UV with DNA damage - inactivation of P53 gene
loss of orderly maturation with variability in nuclear size and shape
hyperkeratosis and parakeratosis
cauliflower like growth
what are the types of squamous cell carcinoma?
superficial
infiltrative - squamous pearls or swirls
what is the histogenesis of basal cell carcinoma?
UV light
involves basal cells
single arangement of basal cells surrounding group of tumor cells (Palisade arrangement)
what is malignant melanoma?
malignant transformation of melanocytes
increased numner of melanocytes with large atypical morphology and haphazardly arranged at the desmosome epidermal junction
may invade the dermis - mets = fatal
etiology - exposure to sunlight
acute, intermittent, blistering
what is von recklinghausens disease?
neurofibromatosis - not a skin lesion!
