Skin Flashcards
Which layer of the skin has desmosomes?
stratum spinosum
atopic dermatitis is what type of HSR?
type I
What are munroe abscesses?
neutrophils in the corneum
-diapedesis occurs at dermal papilla rather than Post cap venule
- seen in psoriasis
What is an auspitz sign?
pinpoint bleeding occurs when psoriatic scale is picked off
What disease is lichen planus associated with?
Hep C
What disease has the 4 “P”s and what are they?
Lichen Planus
- Pruitic
- polygonal
- purple
- papules
In ichthyosis vulgaris what is defective? what is seen histologically?
dec synthesis of profillagrin
- corneum is loose
- granulosum is absent
In x-linked ichthyosis what is deficient? what therefore occurs?
steroid sulfatase
-persistence of cohesion in corneum
What is mutated in lamellar ichthyosis?
TGM1
In darier disease what is mutated and what therefore occurs?
ATP2A2 is mutated - ca2+ dependent assembly of desmosomes is messed up
- multifocal keratoses
- skin colored papules that become encrusted
What causes pemphigus vulgaris?
IgG against desmoglein
- Type II HSR
- acantholysis of stratum spinosum
Describe the nature of the blisters in pemphigus vulgaris?
thin walled bullae that rupture easily
-suprabasal - intraepidermal
What is affected in EB simplex?
cytokeratin IFs
-blisters develop in response to minor trauma
Where does cleavage occur in Junctional EB? What molecule is affected?
- lamina lucida
- Benign: mutation in XVII collagen
severe: laminin and integrin
Where is the split in dermolytic EB and what molecule is affected?
anchoring fibrils
-entire BMZ and epidermis splits
What is the mutation in kindler syndrome and where is the cleavage?
- mutation in FERMT1
- mixed cleavage planes
What causes bullous pemphigoid? where are the blisters?
IgG against hemidesmosomes
- subepidermal blisters
- oral mucosa is spared!
- primarily thighs and trunk
What type of blisters occur in bullous pemphigoid?
tense bullae that dont rupture easily
What causes dermatitis herpetiformis?
igA at tips of dermal papillae
What is the signature rash in erythema multiforme?
targetoid rash with bullae
What is steven johnson syndrome?
severe EM with oral involvement and fever
What is the appearance of a seborrheic keratosis nodule?
“coin stuck on appearance”
-raised discolored plaque
What is the typical word used for the histology of seborrheic keratosis?
pseudocysts
What is leser trelat sign?
sudden onset of multiple seborrheic keratoses
-sign of GI tumor
What is acanthosis nigricans associated with?
insulin resistance or malignancy
What is a buzz word for Basal cell carcinoma?
palisading
What is the most common cancer in transplant patients?
squamous cell carcinoma
What is actinic keratosis a precursor for?
SCC
What is the presentation of keratocanthoma, a well differentiated scc?
cup shaped tumor with keratin debris
What and where are these tumors :
- cylindroma
- syringoma
- poroma
- trichoepithelioma
- sweat gland - on scalp
- eccrine gland - eyelid, cheek
- eccrine gland possibly
- hair structures- face, scalp, neck, trunk
What is the appearance of a dermatofibroma?
pink to brown firm rubbery nodule on extremities
What is the histologic appearance of a dermatofibrosarcoma protuberans? What marker do they display?
spindle cells in a dense pinwheel pattern
-CD34
What is an increase in melanosomes?
freckle
What is an increase in melanocytes?
nevus
what is melasma and what is it associated with?
hyperplasia of cheeks
-estrogen
What is a spindle epithelioid cell nevi called?
spitz nevi
What is the growth pattern in lentigo malignant melanoma?
proliferation along the epidermal-dermal junction
What is the most common type of malignant melanoma?
superficial spreading
How does nodular malignant melanoma spread?
early vertical phase - no radial phase
-epidermis is pushed up creating a nodule
Which form of malignant melanoma is found in dark skinned people and therefore isn’t associated with sun exposure?
acral lentiginous - on the palms and soles
compare and contrast cellulitis and impetigo?
both usually due to staph or strep
-impetigo: children, superficial
-cellulitis: deeper
Where does epidermolysis occur in staph scalded skin syndrome? TEN?
scalded -stratum granulosum
TEN - dermal epidermal junction
What causes molluscum contagiosum?
poxvirus
Where does swelling occur in urticaria? angioedema?
urticaria - superficial dermis
angioedema - deep dermis
