Skin Flashcards
What is the top layer of skin?
Horny Layer
Stratum corneum
What layer is between the Corneum and Spinosum?
Stratum Granulosm
What does the Granule in Granulosm refer to?
Keratinohyaline granules
What layer is between the Stratum Granulosm and the Stratum basalis?
Stratum Spinosum
What is below the dermis in skin?
Subcutaneous fat
What is septae made up
fibrous connective tissue
Why is it important to know about fat lobules?
Because there are inflammatory diseases of fat tissue as well - panniculitis
What is an excoriation?
Scratch: A lesion breaking the epidermis and causing a red linear mark
What is lichenification
Thick/rough skin
Usually occurs due to repeated rubbing
What is a macule
flat circumscribed area that is 5mm or less and distinguished by differing skin color
What is a papule
elevated lesion 5mm or less in diameter
What do you call a macule if it is greater than 5mm?
Patch
nodule
papule that is greater than 5mm
Pustule
Discreet, pus-filled, raised lesion
Pus filled Papule
Scale
Dry, plate-like
from defects in keratinization
Small blister
vesicle
Large blister
bulla
Acantholysis
loss of intercellular adhesion of keratinocytes
Aconthosis
diffuse epidermal hyperplasia
What does -tosis mean
Too much of something and no inflammation
Dyskeratosis
Abnormal keratinization occurring prematurely within individual cells or groups of cells below stratum granulosum
Hyperkeratosis
Hyperplasia of the stratum corneum
Typically a qualitative abnormality of keratin
Lentiginous
Linear melanocyte proliferation along the epidermal basal cell layer
Papillomatosis
Hyperplasia and enlargement of the dermal papillae
Parakeratosis
Keratinization characterized by retention of the nuclei in the stratum corneum
Where is parakeratosis normal?
Buccal mucosa (and in some other mucosae)
Spongiosis
Edema of the epidermis
What does acute inflammation mean in dermatology
Days to weeks (not 24 hours) Mononuclear infiltrate (vs. Neutrophilic)
Describe a plaque
elevated, flat-topped lesion
usually greater than 5mm in diameter
What is the common name for urticaria
hives
What causes hives
dermal microvascular hyperpermeability
What cell is integral to hives
Mast Cells
Urticaria is a Type ___ Hypersensitivity
Type 1
What molecule is released by mast cells to cause hives
Histamine
What are wheals?
Pruritic plaques specific to hives
Type 1
Exposed to antigen
IgE
Mast Cells
Type 2
IgG/IgM
Sensitivity to autoantigen
Type 3
Immune Complex Mediated
Deposition of complex in distant tissue sites
e.g. Lupus
Type 4
Cell mediated
Activated T Cells activate Macrophages
e.g. MS
Allergic contact dermatitis
topical exposure to antigen
Atopic dermatitis
allergic exposure that may have a genetic component
Drug related eczematous dermatitis
Hypersensitivity to a drug
What is pruritus
itching
Erythema Multiforme
Uncommon
Self-limited
Hyper response to drugs
What type of lesion is associated with erythema multiforme
Targetoid
this and lyme disease are the only diseases with it
What causes life threatening forms of E. multiforme
Drugs
What happens with serious forms of E. multiforme?
Sloughing of epidermis (life threatening)
Chronic Inflammatory Dermatoses
Months to Years
Lichenification
e.g. psoriasis, lichen planes, lichen simplex chronicus
Psoriasis
T cells home to dermis and induce hyperplasia and proliferative changes
What risk is increases with psoriases
cardiovascular
What lesions indicate Psoriasis
Salmon colored plaques with silver/white scales
What joint condition is associated with Psoriasis?
Arthritis
Lichen Planus
CD8 response to basal cell layer at dermoepidermal junction
What age group gets lichen planus
Middle aged adults
Prognosis of lichen planus
resolves in 1-2 years but oral version requires treatment
Necrotic basal cells of lichen planus
Civatte bodies
Other lichen planus key terms
Wickham striae
Zig zag dermoepidermal interface
chronicity
Reticular lesion pattern
Lichen simplex chronicus
Roughening of the skin with appearance of lichen on a tree
What causes LSChronicus
response to local trauma such as rubbing or scratching
What is ectasia
dilation of anything in pathology
Impetigo lesion
Small macule that evolves to larger lesion
Honey colored crust of dried serum
What bacterium causes Impetigo
Staph aureus
Strep pyogenes
What causes warts
HPV
What kind of proteins do HPV virions produce
oncoproteins
verruca vulgaris
standard wart
papular rough surface
verruca plana
flat, on palms and face
verruca plantaris/palmaris
foot/hands
Condyloma acuminatum
HPV genital warts
Pemphigus
Group of rare autoimmune blistering disorders
What causes pemphigus lesions
loss of intercellular attachment between epidermal cells and squamous mucosae
Due to autoantibodies to intercellular adhesion molecules
pemphigus vulgaris
suprabasal acantholytic blisters
Pemphigus foliaceus
cutaneous only
subcorneal acantholytic blisters
IgA pemphigus
subcorneal/intraepidermal acantholytic blisters
Paraneoplastic permphigus
He said “bear in mind” when describing the term Paraneoplastic
Pemphigus Pathophysiology
Type II hypersensitivity
IgG in vulgaris
Pemphigus vulgaris direct immunofluorescence
Deposition of antibodies in between all epithelial cell layers
Pemphigus foliaceus immunofluorescence
Autoantibodies deposited mostly in superficial layers of epidermis (sub-corneal acantholytic blister)
Pemphigus vulgaris clinical
middle aged or older
painful blisters
fogo selvageum
bite of black fly lesion
Bullous pemphigoid
Know the difference b/w this and pemphigus for test
Describe pemphigoid bullae
Non acantholytic subepidermal
Rich in eosinophils
Bullous pephigoid clinical
tight bullae don’t rupture (missed the rest)
Dermatitis herpetiformis
very itchy urticaria and grouped vesicles
What is dermatiti herpetiformis associated with
celiac disease
/What type of antibodies are assiciated with D. herpetiformis
granular IgA to epidermal transglutaminase
Where are the IgA deposits found in immunoflurorescene for dermatitis herpetiformis?
Tips of dermal papillae
Discontinuous - only disease with this pattern
Seborrheic Keratosis
Pigmented epidermal tumors in middle to older aged persons
Stuck on appearance
What mutation is associated with SK?
FGF3
What other disease is associated with FGF3 mutations
Achondroplasia
Paraneoplastic
Tumor triggers other problems around the body
What is characteristic of SK from a histologic standpoint
Horn cysts of keratin
Actinic keratosis
Premalignant sun exposure related lesions with prominent hyperkeratosis
Atypia of lower portion of epidermis
recommend excision
Solar elastosis
Grey blue damaged layer due to sun exposure
Squamos cell carcinoma
More men than women
sun exposure
p53 mutation
mutation of HRAS oncogene
Invasion of basement membrane into underlying stroma
What does in-situ mean
full layer thickness without basement membrane penetration
Invasive SCC
Projections of atypical cells into basement membrance
The infiltrative tongues often have keratinization
Basal Cell Carcinoma
Slow growing
Rarely metastasizes
Sun exposure in fair skinned people
Describe BCC lesion
Pearly papule with prominent vascular markings
BCC and Dentistry
Gorlin syndrome with PTCH mutations
What is Gorlin syndrome
Hereditary
Multiple BCCs even at a young age
Keratocystic odotogenic tumors of jaw
Palmar pits
What is Gorlin Syndrome also known as?
Nevoid basal cell carcinoma syndrome
What are benign melanocytic leasions
Nevus
Malignant melanocytic lesions
melanoma
Junctional nevus
flat and pigmented
Compound
Raised and pigmented
Intradermal
Raised and less pigmented because it is skin being pushed up from below
Dysplastic nevi
Features in between benign and malignant
Melanoma v. Nevus
Larger than nevi
Variation in pigmentation
Irregular borders
ABCs of melanoma
Asymmetry Borders Color Diameter Evolution