Skin Flashcards
urticaria (hives) is a common disorder of the skin characterized by localized ____ which leads to _____
urticaria (hives) is a common disorder of the skin characterized by localized mast cell degranulation which leads to dermal microvascular hyperpermeability
urticaria is due to ___-induced release of ____ from mast cells, which makes it a type ___ hypersensitivity
urticaria is due to antigen-inducedrelease ofvasoactive mediatorsfrom mast cells, which makes it atype 1hypersensitivity
list the common causes of urticaria
pollen
food
drugs (opiates, aspirin)
insect venom
on microscopic examination of urticaria, there are sparse superficial ____ consisting of ____ cells +/- ____ and _____
on microscopic examination of urticaria, there are sparse superficial perivenular infiltrate consisting of mononuclear cells +/- neutrophils and eosinophils
___ are more widely spaced as a result of superficial dermal edema, and ____ channels become dilated
collagen bundles are more widely spaced as a result of superficial dermal edema, and superficial lymphatic channels become dilated
allergic contact dermatitis stems from ____ exposure to an allergen and is caused by _____ reactions
allergic contact dermatitis stems from topical exposure to an allergen and is caused by delayed hypersensitivity reactions
atopic dermatitis is caused by defects in ____ defined as skin with increased ____; it has a ____ predisposition
atopic dermatitis is caused by defects in keratinocyte barrier function defined as skin with increased permeability to substances to which it is exposed; it has a genetic predisposition
describe the pathogenesis of delayed hypersensitivity reaction
in acute eczematous dermatitis, ___ occurs, which is edema that seeps into the intercellular spaces of the ___, splaying apart ____ particularly in the ____
in acute eczematous dermatitis, spongiosis occurs, which is edema that seeps into the intercellular spaces of the epidermis, splaying apart keratinocytes particularly in the stratum spinosum
acute eczematous dermatitis is characterized by superficial, perivascular ____ infiltrate associated with ____ edema and ____ degranulation
acute eczematous dermatitis is characterized by superficial, perivascular lymphocytic infiltrate associated with papillary dermal edema and mast cell degranulation
psoriasis is caused by an ____ disorder with shorter ____ resulting in build-up of scales
psoriasis is caused by an erthro-squamousdisorderwithshorter cell maturation resulting in build-up of scales
15% of patients with psoriasis have associated ___
15% of patients with psoriasis have associated arthritis (any joint, can be symmetrically involved)
psoriasis has a strong association with HLA-____
psoriasis has a strong association with HLA-C
lesions in psoriasis can be induced in susceptible individuals after local trauma, also known as ____ phenomenon
lesions in psoriasis can be induced in susceptible individuals after local trauma, also known as Koebner phenomenon
psoriasis is caused by sensitized populations of ____ and ____ cells as well as activated _____ cells that enter the skin and accumulate in the ____
psoriasis is caused by sensitized populations of CD4 Th1 and Th17 cells as well as activated CD8cells that enter the skin and accumulate in the epidermis
the CD4 cells and CD8 cells that accumulate in the epidermis in psoriasis secrete ____ (4 cytokines) which cause ____ proliferation
the CD4 cells and CD8 cells that accumulate in the epidermis in psoriasis secrete IL-12, TNF, IFN-gamma, IL-17 which cause keratinocyte proliferation
early psoriatic lesions are ____ pustules
while
later lesions are ____-demarcated, symmetrical, ___-colored plaques covered by loosely adherent ____
early psoriatic lesions are erythematous pustules
while
later lesions are well-demarcated, symmetrical, salmon-colored plaques covered by loosely adherent silvery scales
describe the nail changes seen in psoriasis
discoloration
dimpling/pitting
on microscopic examination of psoriasis, there is acanthosis, which is _____
on microscopic examination of psoriasis, there is acanthosis, which is diffuse epidermal hyperplasia (implies increased thickness of the Malpighian layer)
on microscopic examination of psoriasis, there are downward elongation of ____ as well as thinned ____ with extensive ____ scales
on microscopic examination of psoriasis, there are downward elongation of rete ridges as well as thinned stratum granulosum with extensive parakeratotic scales
on microscopic examination of psoriasis, ____ form small aggregates in superficial epidermis, forming ____
on microscopic examination of psoriasis, neutrophils form small aggregates in superficial epidermis, forming pustules
describe the image and what condition it is seen in
psoriasis
resolution of Lichen Planus leaves post-inflammatory ____
resolution of Lichen Planus leaves post-inflammatory hyperpigmentation
the oral lesion in Lichen Planus may persist for years, where the chronic mucosal lesions can result in ____
the oral lesion in Lichen Planus may persist for years, where the chronic mucosal lesions can result in squamous cell carcinoma
the pathogenesis of Lichen Planus is altered antigens in ____ elicit a ____ cell response
the pathogenesis of Lichen Planus is altered antigens in basal epidermal cells elicit a CD8 T cell response
describe the clinical presentation of Lichen Planus
6 P’s of Lichen Planus
pruritic
purple
Polygonal Planar Papules
plaques
the lesions in Lichen Planus are usually multiple, ____ distributed on the extremities, often around the ___ and ____
the lesions in Lichen Planus are usually multiple, symmetrically distributed on the extremities, often around the wrists and elbows
the papules in Lichen Planus are often highlighted by ___ dots or lines called ____ which are created by areas of ____
the papules in Lichen Planus are often highlighted by white dots or lines called Wickham striae which are created by areas of hypergranulosis
what is seen in the image and what condition is characterized by these lesions?
on microscopic examination of Lichen Planus, ____ show degeneration and necrosis which leads to an angular contour/____ of the rete ridges
on microscopic examination of Lichen Planus, basal keratinocytes show degeneration and necrosis which leads to an angular contour/saw-toothing of the rete ridges
on microscopic examination of Lichen Planus, there are dense, continuous ____ infiltrate at the ___ junction
on microscopic examination of Lichen Planus, there are dense, continuous lymphocytic infiltrate at the dermo-epidermal junction
describe the image and the condition it is seen in
lichen planus
superficial fungal infections of the skin are confined to the stratum ____ and are caused primarily by ____
superficial fungal infections of the skin are confined to the stratum corneum and are caused primarily by dermatophytes
tinea capitis usually occurs in children and causes ____ patches of skin associated with mild ___, ___ formation and ____
tinea capitis usually occurs in children and causes hairless patches of skin associated with mild erythema, crust formation and scaling
tinea corporis is seen in persons of all ages (but especially children) and occurs in cases of excessive ___ and ___, exposure to ____
tinea corporis is seen in persons of all ages (but especially children) and occurs in cases of excessive heat and humidity and exposure to infected animals
tinea corporis is characterized by an expanding, round, slightly erythematous ____ with an elevated _____
tinea corporis is characterized by an expanding, round, slightly erythematous plaque with an elevated scaling border
organisms causing tinea may be identified in scrapings with ___ mount or ____ stain
organisms causing tinea may be identified in scrapings with KOH mount or PAS stain (bright pink to red)
pemphigus vulgaris is a blistering disorder caused by autoantibodies against ____ within the ___ and ___
pemphigus vulgaris is a blistering disorder caused by autoantibodies against desmosomes within the epidermis and mucosal epithelium
in pemphigus vulgaris, the ____ lesions precede the ____ lesions, and these lesions are associated with ____
in pemphigus vulgaris , the oral lesions precede the skin lesions, and these lesions are associated with pain
pemphigus vulgaris is caused by ____ autoantibodies against ____ which disrupts the ____
pemphigus vulgaris is caused by IgG autoantibodies against desmogleins which disrupts the desmosomes
do the lesions in pemphis vulgaris rupture easily?
YES, lesions rupture easily and leave shallow erosions covered with dried serum and crust
in pemphigus vulgaris, there is ____ in the supra-basal layer
in pemphigus vulgaris , there is acantholysis in the supra-basal layer
on direct immunofluorescence in pemphigus vulgaris, lesions show a characteristic ____ pattern of ____ deposits
on direct immunofluorescence in pemphigus vulgaris , lesions show a characteristic net-like pattern of intercellular IgG deposits
explain the image and the condition it is seen in
in bullous pemphigoid, the ____ lesions appear first followed by the ____ lesions
in bullous pemphigoid, the cutaneous lesions appear first followed by the oral lesions
bullous pemphigoid is caused by ___ autoantibodies to _____, where the antibody deposition occurs in a ____ pattern at _____
bullous pemphigoid is caused by IgG autoantibodies to hemidesmosomes, where the antibody deposition occurs in a linear pattern at dermo-epidermal junction
in bullous pemphigoid, the autoantibodies also activate ___ which recruit ___ and ____ and disrupt epidermal attachment
in bullous pemphigoid, the autoantibodies also activate complement which recruit neutrophils and eosinophils and disrupt epidermal attachment
do the lesions seen in bullous pemphigoid rupture easily?
NO, they are tense bullae that do not rupture easily and heal without scarring
describe the Nikolsky sign for pemphigus vulgaris vs. bullous pemphigoid
Nikolsky sign = lesions rupturing upon contact
pemphigus vulgaris = POSITIVE Nikolsky sign
bullous pemphigoid = NEGATIVE Nikolsky sign
dermatitis herpetiformis is associated with ___ and responds well to ___ diets
dermatitis herpetiformis is associated with Celiac disease and responds well to gluten-free diets
in dermatitis herpetiformis, ___ antibodies cross-react with ____ which is an anchoring filament that tethers the ___ to the ____
in dermatitis herpetiformis, IgA antibodies cross-react with reticulin which is an anchoring filament that tethers the epidermis to the superficial dermis
in dermatitis herpetiformis, ___ and ___ accumulate at the tips of dermal papillae forming ____
in dermatitis herpetiformis, fibrin and macrophages accumulate at the tips of dermal papillae forming micro-abscesses
in dermatitis herpetiformis, the basal layer overlying the microabscesses show ___ and ____ which ultimately forms bilsters
in dermatitis herpetiformis, the basal layer overlying the microabscesses show vacuolization and dermoepidermal separation which ultimately forms bilsters
on direct immunofluorescence in dermatitis herpetiformis, it shows ____ granular deposits of ___ that selectively localize in the ____
on direct immunofluorescence in dermatitis herpetiformis, it shows discontinuous granular deposits of IgA that selectively localize in the tips of dermal papillae
describe the image and the condition it is seen in
dermatitis herpetiformis
seborrheic keratosis is caused by ___ mutations in ____ pathway
seborrheic keratosis is caused by activating mutations in FGFR3 signaling pathway
describe the appearance and color of lesions seen in seborrheic keratosis
round, exophytic, coin-like plaques
tan to dark brown with velvety surface
seborrheic keratosis is a benign neoplasm of ____ cells with _____
seborrheic keratosis is a benign neoplasm of basal cells with melanin pigmentation
seborrheic keratosis is ___ at the surface with ___-filled cysts
seborrheic keratosis is hyperkeratosis at the surface with keratin-filled cysts
actinic keratosis is caused by ___ exposure
actinic keratosis is caused by sun exposure
actinic keratosis is caused by ___-induced DNA damage, with ___ mutations
actinic keratosis is caused by UV-induced DNA damage, with TP53 mutations
actinic keratosis may rarely progress to ____
actinic keratosis may rarely progress to squamous cell carcinoma
the color of actinic keratosis is ___ and has a ____-like feel to touch
the color of actinic keratosis is tan-brown to red and has a sandpaper-like feel to touch
on microscopic examination of actinic keratosis, there is cytologic ___ and hyperplasia of ____ cells
on microscopic examination of actinic keratosis, there is cytologic atypia and hyperplasia of basal cells
on microscopic examination of actinic keratosis, the superficial dermis has grey-blue ___, which is called ____
on microscopic examination of actinic keratosis, the superficial dermis has grey-blue elastic fibers, which is called elastosis
squamous cell carcinoma of the skin is due to DNA damage induced by ____
squamous cell carcinoma of the skin is due to DNA damage induced by exposure to UV light
list other predisposing factors for squamous cell carcinoma of the skin
___ and ___ mutations are implicated in squamous cell carcinoma of the skin
TP53 and KRAS mutations are implicated in squamous cell carcinoma of the skin
the lesions in squamous cell carcinoma of the skin appear as ____ defined, red, scaly papules or plaques
the lesions in squamous cell carcinoma of the skin appear as sharply defined, red, scaly papules or plaques
invasive squamous cell carcinomas of the skin are usually nodular with ____ scales and may ____
invasive squamous cell carcinomas of the skin are usually nodular with hyperkeratotic scales and may ulcerate
squamous cell carcinoma of the skin can arise from which precancerous lesion?
actinic keratosis
on microscopic examination of squamous cell carcinoma of the skin, the cells are enlarged and ____ cells are see in ____ of the epidermis
on microscopic examination of squamous cell carcinoma of the skin, the cells are enlarged and hyperchromatic cells are see in all layers of the epidermis
_____ is the most common invasive cancer in humans
basal cell carcinoma is the most common invasive cancer in humans
basal cell carcinomas are due to mutations that activate the ___ signaling pathway
basal cell carcinomas are due to mutations that activate the Hedgehog signaling pathway
basal cell carcinoma presents as ___ papules with ____
basal cell carcinoma presents as pearly papules with telangiectasia
basal cell carcinoma tumor cells resemble ___ cells and are therefore not seen over ____
basal cell carcinoma tumor cells resemble basal germinitive cells and are therefore not seen over mucosal surfaces
describe the 2 types of basal cell carcinomas
multifocal superficial growths: originate from epidermis
nodular lesions: growing into dermis as cord of basophilic, hyperchromatic cells in a fibrous or mucinous stroma
in malignant melanomas, mutations involving which 3 genes are more frequently implicated?
p16
RAS
BRAF
list features that confer a better prognosis for malignant melanoma
lesser depth
none or very few mitoses
tumor infiltrating lymphocyte response
lack of ulceration
lack of regional LN involvement
