Term
| designations of skin color |
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Definition
| constitutive vs. facultative |
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Term
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Definition
| constitutive skin pigmentation = "baseline" genetically determined color in the absence of sun exposure |
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Term
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Definition
| facultative skin pigmentation = coloring that results after secondary melanin induction |
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Term
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Definition
| SPT: skin phototype system |
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Term
skin phototype system
(SPT) |
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Definition
categorizes skin based on reactions to UV radiation
correlates color of the skin with its ability to respond to UV light with burning or tanning
6 types: I-very sensitive, no tan; VI-very resistant, natural black skin |
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Term
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Definition
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Term
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Definition
melanocytes are derived from neural crest cells
populate the skin, eye, cochlea, meninges, hair follicle
(number of melanocytes does NOT determine skin color) |
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Term
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Definition
melanocytes associated with nearby keratinocytes
along basal layer
associate via multiple dendritic processes |
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Term
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Definition
melanocytes synthesize melanin
melanin production is determined by activity of TYROSINASE
tyrosinase activity is increased in darkly pigmented individuals, leading to increased melanin production |
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Term
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Definition
melanin is stored in melanosomes
melanosomes transported to nearby keratinocytes
-protect from UV radiation
-most concentrated in basal cells
-preferentially cap the nuclei
skin color differences are due to melanosomes |
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Term
| melanosomes and skin color |
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Definition
melanosomes can differ among individuals in terms of number, size, and aggregation
dark pigmentation: larger melanosomes that are ore individually dispersed |
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Term
| normal variants in pigmented skin |
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Definition
pigmentary demarcation lines
pigmented gums
dermal melanocytes
longitudinal melanonychia
punctate keratosis of palmar creases |
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Term
| pigmentary demarcation lines |
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Definition
abrupt transition between lighter ventral and darker dorsal skin
may be photoprotective |
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Term
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Definition
pigmentation of oral mucosa is common in dark skin
most commonly seen on gingiva
subtle, symmetric, respects natural borders |
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Term
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Definition
melanocytes in dermis, results in blueish hue
Nevus of Ota and Ito
congenital |
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Term
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Definition
common in Asians, Africans
Ota: first 2 branches of trigeminal nerve, often unilateral
Ito: scapular, posterior supraclavicular distribution |
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Term
| congenital dermal melanocytosis |
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Definition
aka "mongolian spot"
most common in Asians
usually resolves during childhood
sacral region very common |
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Term
| longitudinal melanonychia |
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Definition
-stripes of pigment under the nail bed
-increased melanocytes in the nail matrix
-appearance often darkens with age
-single band can be hard to distinguish from a melanoma
-when benign, often see multiple bands |
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Term
| punctate keratosis of palmar creases |
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Definition
-AD
-overgrowth of top layer of skin
-small, hypertrophic plugs in the large creases of palms and fingers
-appearance during adolescence
-aggravated by manual work
-often misdiagnosed as warts |
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Term
common dermatoses with variable presentations
many common conditions can have different appearances in darker vs. lighter skin |
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Definition
pink or mild erythema may not be detectable
reds and brown can appear purples or grey
post-inflammatory changes may be the only remaining lesion |
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Term
| eczema in light vs. dark skin |
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Definition
light: bright pink/red, with overlying crusting
dark: dryness/scaling more prominent, more hyperpigmentation as a reflection of erythema
distribution and symptoms similar
both have scale
both have exocoriations |
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Term
| seborrheic dermatitis in light vs. dark skin |
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Definition
light: sharply demarcated pink patches with white to yellow scaling
dark: pigmentary change (lighter or darker) may be the only detectable change |
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Term
| folliculitis in light vs. dark skin |
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Definition
| dark: erythema can be hidden, may present with hyperpigmented macules only |
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Term
| dermatomyositis in light vs. dark skin |
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Definition
light: erthematous
dark: slight hyperpigmentation |
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Term
| skin diagnoses and skin color |
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Definition
| different races have different skin concerns |
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Term
| most common diagnoses of Caucasian skin |
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Definition
acne
lesion of unspecified behavior
benign neoplasm of skin
contact derm/eczema
psoriasis |
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Term
| most common diagnoses of black skin |
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Definition
acne
dyschromia
contact derm/eczema
alopecia
seborrheic dermatitis |
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Term
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Definition
acne occurs at similar rates in most groups
darker skin:
-lower incidence of nodulocystic acne
-acne hyperpigmented macule biggest compliant
-higher incidence of keloid scarring |
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Term
| pseudofolliculitis barbae |
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Definition
"razor bumps"
when hair follicle reenters the skin - can get a foreign body rxn with swelling, inflammation (erythematous papulaes and pustules)
shaving can traumatize pustules, more inflammation
can get keloid formation |
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Term
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Definition
chronic, progressive keloidal scarring of the nape of the neck
follicular inflammation -> rupture of follicle -> foregin body reaction -> scarring -> keloids, alopecia
difficult to treat |
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Term
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Definition
-multiple pigmented papules on the face and neck
-35% of blacks, most have a positive family history
-start after adolescence and slowly increase in number
-mostly concentrated in the malar regions, temples
-histologically represent tiny seborrheic keratoses |
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Term
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Definition
-dyschromia is the #2 complaint among patients of color
-most present with post-inflammatory hyperpigmentation
-hypopigmentation possible too
PIH
dyschromia
melasma
pityriasis alba
vitiligo |
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Term
post-inflammatory hyperpigmentation
(PIH) |
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Definition
labile response of melanocytes to irritiation or inflammation
yes cosmetic, but pigment changes can have significant psychological impact |
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Term
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Definition
more constitutive pigment increased probability of developing dyspigmentation
-may be hyper or hypopigmentation
cytokines associated with inflammation may cause melanocytes to make more or less melanin
may take months to years to resolve |
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Term
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Definition
benign, symmetric facial hyperpigmentation primarily in women
genetic and hormonal factors, UV radiation, lability of melanocytes
can develop during/after pregnancy |
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Term
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Definition
multiple hypopigmented, ill-defined, slightly scaly patches
may be a variant of PIH after eczema
usually resolves during adolescence due to increased sebum production |
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Term
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Definition
hypopigmentation
clinically more apparent in dark skin, though incidence if similiar
autoimmune component to pathogenesis
sunscreen is essential to both involved and uninvolved skin |
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Term
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Definition
3-18 times for often in dark-skinned patients
abnormal fibroblast activity
-increased collagen production
-abnormal responses to stimulation
trauma, unsretrained growth of scar tissue
grow BEYOND SITE OF INJURY |
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Term
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Definition
intralesional steroids
cryotherapy
silicone gel
surgical excisions
phototherapy
lasers |
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Term
| skin caner in pigmented skin |
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Definition
SCC is most common skin cancer in blacks
-often in non sun exposed areas
BCC - RF: lighter pig
melanoma - most in non sun exposed sites, high metastatic rates |
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Term
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Definition
hair loss
many types are scarring alopecia
-follicular scarring - no potential for regrowth
-discoid lupus, traction alopecia, central centrifugal cicatricial alopecia, lichen planopilaris |
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Term
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Definition
after repeated tension on hair
tight braids, ponytails, extensions
commonly on temporal or frontal region
biphasic air loss
-initially, is temporary and can regrow
-becomes permanent if excessive traction persists |
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