7 - Skin Flashcards
(210 cards)
1
Q
what structures of the skin are not present in the oral cavity
A
sweat glands and sebaceous glands
2
Q
what is a highly sophisticated sensory organ
A
skin
3
Q
skin plays a role in the synthesis of what
A
vitamin D
4
Q
what is the first line of defense against potentially harmful infectious physical agents
A
skin
5
Q
what has nerve endings to sense hot, cold, etc.
A
skin
6
Q
what are the cell types of the skin
A
- squamous epithelial cells (keratinocytes)
- melanocytes
- dendritic cells (Langerhans cells)
- lymphocytes
7
Q
squamous epi cells are glued together by what
A
desmosomes
8
Q
squamous epi cells produce an abundant amount of what
A
keratin protein
9
Q
what do squamous epi cells secrete
A
soluble molecues (e.g., cytokines and defensins that augment and regulate immune responses)
10
Q
how do squamous epi attach to basement mem
A
hemidesmosomes
11
Q
what is within the epidermis and is responsible for producing melanin
A
melanocytes
12
Q
what processes microbial and nonmicrobial agents that the skin is exposed to
A
dendritic cells (langerhans)
13
Q
what protects the skin against cutaneous inflammatory and infectious diseases
A
T and B lymphocytes
14
Q
what is responsible for feelings of touch, vibration, itchiness, cold, and heat in the skin
A
AFFERENT NERVE FIBERS and diverse set of associated structures called NEURAL END ORGANS
15
Q
what guard against deletrious variations in body temp
A
sweat glands
16
Q
what manufacture hair shafts and have protects niches harboring epi stem cells capable of regenerating superficial epi skin structures following disruption by trauma, burns, and other types of injuries
A
hair follicles
17
Q
what are the disorders of melanocytes and nevus cells
A
- Freckle (ephelis)
- Lentigo
- Melanocytic nevus
- Dysplastic nevus
- Melanoma
18
Q
about how many keratinocytes equal one melanocyte
A
10-20
19
Q
what is the maturation sequence of nevi
A
normal skin shows scattered dendritic melanocytes within epidermal basal cell layerh
20
Q
what are aggregates of round nevus cells that brow along dermoepidermal junction
A
junctional nevus
21
Q
what are nevus cells seen in epidermis and dermis
A
compound nevus
22
Q
what are nevus cells only in the dermis
A
intradermal nevus
23
Q
what are the most common pigmented lesions of childhood in lightly pigmented individuals
A
freckle (ephelis)
24
Q
what are small (one to several mm), tan-red to light brown macules (flat lesions) that appear after sun exposure
A
freckle (ephelis)
25
what results from increased amounts of melanin pigment within basal keratinocytes
freckle (ephelis)
26
T/F: when freckles arise, melanocytes increase
FALSE! number of melanocytes remain the same
27
are freckles capable of fading and darkening depending on the season?
YES
28
what results from benign localize hyperplasia of melanocytes
lentigo
29
when does lentigo appear
all ages - but most common in infants and children
30
what does lentigo involve
skin and mucous membranes
31
what does lentigo appear as
small (5-10 mm), oval tan brown macules
32
T/F: lentigo darkens when exposed to sunlight
FALSE
33
what is solar lentigo
lentigo appear in older people due to sun damage
34
what is a flat lesion that is hyper or hypo pigmented
macule
35
what are benign neoplasms by acquiring activating mutations in components of BRAF or less often RAS signaling pathways
melanocytic nevus (moles)
36
what are tan to brown, uniformly pigmented, small (< 6mm) relatively flat macules or elevated papules (small round topped elevated lesion) with well-defined, rounded borders
melanocytic nevus (moles)
37
are nevus cells rounded cells
yes
38
origin of nevus cells
neural crest
39
small bump = ___
large bump = ___
papule; nodule
40
what is a direct precursor of melanoma
dysplastic nevus (but a vast majoring never progress to melanoma)
41
when ___ increased in number they are a marker of an increased risk for melanoma
dysplastic nevus
42
how does dysplastic nevus appear
macules or target like lesions (dark raise center and irregular flat periphery)
43
what are slightly raised plaques (raised lesions with flat surface)
macules
44
does dysplastic nevus occur in sun exposed or protected body surfaces
occurs in BOTH!
45
what is the most deadly of skin cancers?
melanoma
46
what mutation causes skin cancer
BRAF mutations due to exposure to UV radiation in sunlight
47
can melanoma be inherited?
YES! 10-15% inherited as AD trait w/ variable penetrance
48
what is the ABCDE of melanoma?
1. ASYMMETRIC lesions
2. BORDERS are irregular and often notched
3. COLOR is variable and not uniform
4. DIAMETER is larger than nevi and increasing
5. EVOLVING/evolution - lesions are constantly enlarging either superficially or in nodular fashion
49
what is the size of melanoma lesions
>6 mm
50
when (age) does seborrheic keratosis frequently occur
common but most frequently occurs in middle-aged or older individuals
51
where is seborrheic keratosis numerous
trunk
52
small SK on the face in people of color are called what
dermatosis papulose nigra (seen in 35% of African-American adults)
53
seborrheic keratosis may appear suddenly in large numbers as part of what
paraneoplastic syndrome (Leser-Trelat sign) a sign of potential internal cancer
54
what are round, elevated, coin-like waxy plaque that varies in diameter from mm to several cm "pasted on" look
seborrheic keratosis
55
what is uniformly tan to dark brownl velvety to granular surface
seborrheic keratosiss
56
what is a thickened, hyperpigmented skin with velvet-like texture
acanthosis nigricans
57
where does acanthhosis nigricans most commonly appear
flexural areas (axillae, skin folds of neck, groin-area where upper thighs meet the lowest part of abdomen, and anogenital areas)
58
what are the 2 types of acanthosis nigricans
1. 80% - benign conditions (gradually during childhood and puberty)
2. 20% - associated with cancers (most commonly GI adenocarcinomas)
59
what malignant cancer would acanthosis nigricans be associated with
GI adenocarcinoma (in middle-aged or older individuals)
60
what is an important cutaneous sign of several underlying benign and malignant conditions
acanthosis nigricans
61
what are benign disease acanthosis nigricans associated with
insulin resistance, DM, PCOS, thyroid disorder, adrenal gland disorders, and medications
62
what are fibroepithelial polyps also called
skin tag and acrochordon
63
where are skin tags present? age?
middle-aged or older individuals -> neck, trunk, and face
64
what are soft, flesh-colored bad like tumros often attached to surrounding skin by slender stalk
fibroepithelial polyp (Skin tag)
65
what can undergo ischemia due to torsion which may cause pain and precipitate their removal
fibroepithelial polyp (skin tag)
66
are adnexal (appendage) tumors benign or malignant
BOTH (either benign or malignant)
67
what is adnexal tumors associated with
germline mutations of tumor suppressor genes
68
what may be numerous and disfiguring OR relativelly trivial but warn predisposition of an internal malignancy
Adnexal (appendange) tumors
69
what is this an example of:
relationship between multiple trichilemmomas (benign tumor arising from hair follicle) and Cowden syndrome, a disorder caused by germline mutation gene PTEN that is associated with an increased risk of endometrial cancer, breast cancer, and other malignancies
adnexal (appendage) tumors
70
what are benign tumor of sweat gland
cylindroma (turban tumor)
71
where does cylindroma usually occur
forehead and scalp where coalescene of nocules with time may produce hat like growth
72
is cylindroma AD or AR? when does it appear?
AD - appears early in life
73
what is associated with inactivation of tumor suppresor gene CYLD
cylindroma (CYLD is the cylindromatosis gene)
74
what is a benign tumor of sebaceous glands
sebaceous adenoma
75
what can be associated w/ internal malignancy in Muir-Torre syndrome
sebaceous adenoma
76
what is defined as the occurrence of at least one sebaceous-gland tumor, or keratoacanthoma, in conjunction with internal malignant diseases, often in the GI tract
sebaceous adenoma
77
what are benign tumors of hair follicle, common on face and neck
pilomatricoma
78
how does pilomatricoma usually appear
solitary nodule, occasionally multiple nodules occur
79
where does actinic keratosis occur? what does it exhibit
sun damaged skin and exhibit hyperkeratosis
80
is actinic keratosis greater in light or dark skin individuals
light skinned
81
what may show progressively worsening dysplatic changes that culminate in squamous cell carcinoma
actinic keratosis
82
what is the dimension of actinic keratosis
<1 cm
83
what is a tan-brown, red, or skin-colored and have a rough sandpaper-like consistency
actinic keratosis
84
does actinic keratosis remain stable or regress?
it can remain stable BUT can regress to enough lesions to transform to a malignant lesion (squamous cell carcinoma)
85
is local eradication necessary in actinic keratosis? if so, how
yes - gentle curettage, freezing, topical application of chemotherapeutic agents (imiquimod)
86
what is the second most common tumor arising in sun exposed sites in older people
squamous cell carcinoma
87
squamous cell carcinoma more common in men or women? exception?
men BUT in lower leg lesions more common in women
88
what percent of squamous cell carcinoma metastasize to regional lymph nodes
<5%
89
what is the most common cause in DNA damage resulting in squamous cell carcinoma? second cause?
1. exposure to UV light
2. chronic immunosuppression
90
what are other risk factors to DNA leading to squamous cell carcinoma
(1. exposure to UV light
2. chronic immunosuppression)
3. tobacco
4. betel nut chewing
5. industrial carcinogens
6. ionizing radiations
7. chronic ulcers
8. old burn scars
91
what is the most common muted gene that leads to SCC?
TP53
92
what is the general muted gene that leads to SCC?
NOTCHI
93
Distinctive, locally aggressive cutaneous tumor
associated with mutations in PTCHI PTCH2, SMO
and SUFU genes
basal cell carcinoma
94
what is the most common locally invasive cancer in humans
basal cell carcinoma
95
is BCC slow growing or fast? are they common or rarely metastazie
slow growing; rarely metastasize
96
what occurs on sun exposed skin; incidence increases in setting of immunosuppression, has pearly papules
basal cell carcinoma
97
what is present on the papules of BCC?
telangiectasia (new BV forming)
98
nevoid basal cell carcinoma syndrome is also called what
gorlin syndrome
99
is gorlin syndrom AD or AR? this is a mutation of what gene
AD - mutation of tumor suppressor gene PTCH
100
what is gorlin syndrome characterized by
1. Development of multiple BCCAs, often before age 20
2. Accompanied by various other tumors, especially medulloblastoma and ovarian fibroma
3. Odontogenic keratocysts
4. Palmar and plantar pits
101
what is a benign dermal tumor of UNCERTAIN lineage often seen on legs of young and middle-aged women, asymptomatic or tender
benign fibrous histiocytomas (dermatofibroma)
102
are dermatofibroma capable of increasing or decreasing in size over time
yes
103
cause of dematofibroma
unknown -> few cases show ALK gene mutation
104
what is a first, tan to brown papule usually <1 cm in diameter; actively growing lesions may reach several cm
dermatofibroma
105
what is a well-differentiated primary fibrosarcoma of the skin
dermatofibrosarcoma protuberance
106
is dermatofibrosarcoma protuberance slow or fast? local or systemically aggresive? common or rarely metastazie?
slow growing
locally agressive
rarely metastasize
107
what results with the translocation involving the gene encoding collagen I A I and platelet derived growth factor beta
dermatofibrosarcoma protuberance
108
what appears as a protuberant nodule, within a form plaque which may ulcerate; most often on the trunk
dermatofibrosarcoma protuberance
109
Lymphoma of skin-homing CD4+ T-helper cells that presents in the skin
mycosis fungoides (cutaneous T-cell lymphoma)
110
does mycosis fungoides remain localize in skin?
yes it remains localized for many years but may eventually evolve into systemic lymphoma
111
when does mycosis fungoides occure (age)?
>in people older than 40 but may occur at any age in truncal areas
112
Scaly red-brown patches; raised scaling plaques that may
be confused with psoriasis
mycosis fungoides
113
what is the seeding of blood with malignant T cells resulting in erythema and scaling of entire body
Sezary syndrome (related to mycosis fungoides)
114
Disorder associated with excessive keratin buildup (hyperkeratosis) that result in fish-like scaliness
ichthyosis
115
when does ichthyosis appear
at or around the time of birth
116
is ichthyosis acquired or inherited?
BOTH!
acquired is associated with lymphoid or visceral malignancies
inherited (occurs later in life)
117
Common; usually caused by localized degranulation of mast cells and is uniformly associated with dermal microvasculature hyperpermeability
urticaria (hives)
118
what produces pruritic edematous plaques called wheals; small pruritic papules to large erythematous plaques
urticaria (hives)
119
when does urticaria (hives) common (age)? where?
> between ages 20 and 40; all ages are susceptible; > in areas exposed to pressure (trunk, distal extremities, and ears)
120
when do hives develop and fade? how long?
Individual lesions develop and fade within hours (usually, 24
hours); episodes may last for days or persist for months
121
how to treat uticaria (hives)
Treatment: antihistamines; oral corticosteroids
122
Uncommon; self-limiting hypersensitivity reaction to
certain infections and drugs
erythema multiforme
123
what age does erythema multiforme occur
any age
124
what is erythema multiformed associated with
1. infections (YOUNG PEOPLE)
2. exposure to certain drugs (OLDER PEOPLE)
3. cancers
4. collagen vascular disease
ICCE
125
erythema multiforme is characterized by what injury? what cells?
Characterized by keratinocyte injury mediated by skin-homing CD 8+ cytotoxic T lymphocytes
126
what are the diverse array of lesions present in erythema multiforme
macules, papules, vesicles, bullae, and characteristic targetoid lesions
127
erythema multiforme often show ___ on extremities
symmetric distribution
128
what is a febrile form of erythema multiforme associated with extensive involvement of the skin; lesions also involve the lips, oral mucosa, conjunctiva, urethra, and genital and perianal areas
Stevens-Johnson Syndrome
129
what is characterized by diffuse necrosis and sloughing of cutaneous and mucosal epithelial surface (in relation to erythema multiformed)
toxic epidermal necrolysis (TEN)
130
what is chronic inflammatory dermatosis that appears to have an autoimmune basis
psoriasis
131
are environmental and genetic factors at play in psoriasis
yes
132
what areas of skin are psoriasis affected
1. knees
2. elbows
3. scalp
4. lumbosacral areas
5. intergluteal clefts
6. glans penis
133
Well-demarcated, pink to salmon-colored plaques covered by loosely adherent silver-colored scales
psoriasis
134
what is a local trauma that can induce psoriatic lesions in susceptible individuals
Koebner phenomenon
135
what is a chronic inflammatory dermatosis that is more common than psoriasis
chronic inflammatory dermatosis
136
what involves regions with high density of sebaceous glands but is NOT a sebaceous gland disease
seborrheic dematitis
137
what causes seborrheic dermatitis
UNKOWN - increased sebum production is a contributory factor
138
what has macules and papules on an erythematous yellow, often greasy base, associated with scaling and crusting
seborrheic dematitis
139
what is the most common clinical expression of seborrheic dermatitis
dandruff
140
whata disorder of skin and mucous membrane
lichen planus
141
what are the 6Ps associated with lichen planus
1. pruritis
2. purple
3. polygonal
4. planar
5. papules
6. plaques
142
what are itchy, purple, flat-topped, papules that may coalesce to form plaques; symmetrically distributed and multiple lesions
lichen planus
143
are lichen planus self-limiting? when do they resolve
yes and may resolve 1-2 years after onset
144
how long do ORAL lichen planus lesions persist
YEARS
145
pathogenesis of lichen planus
unknown
146
what can be seen in relation to lichen planus
Wickhams striae (radiating white lines)
147
what age is lichen planus present
> in middle aged and on extremities
148
what are inflammatory blistering disorders
1. pemphigus
2. bullous pemphigoid
149
what are noninflammatory blistering disorders
epidermolysis bullosa
150
what is desmosome made of
desmoglein 1 or 3
151
what is a blistering disorder caused by autoantibodies (IgG) that result in dissolution of intracellular attachments (desmoglein of DESMOSOMES) within the epidermis and mucosal epi?
pemphigus
152
when does pemphigus occur? m or f?
4-6th decade of life, equal in both M and F
153
what is the most common variant of pemphigus that involves skin and mucosa
pemphigus vulgaris
154
T/F: oral ulcers may persist for years before pemphigus skin lesion appear
TRUE
155
primary lesions of pemphigus
vesicles or bullae that rupture easily, leaving shallow erosions
156
what skin disease has a chicken wire looking cells in microscope
pemphigus vulgaris
157
what is caused by autoantibodies that bind to the proteins (HEMIDESMOSOMES) that are required for adherence of basal keratinocytes to the basement membrane
bullous pemphigoid
158
in bullous pemphigoid, antibody deposition occurs in continuous linear pattern where?
dermoepidermal junction
159
what are tense bullae filled with clear fluid involving erythematous or normal appear skin, 2 cm in diamer, and do not rupture easily
bullous pemphigod
160
does bulloud pemphigoid heat with scarring?
NO! heals without scarring
161
how does bullous pemphigoid appear in microscopy
linear band of antibodies that DO NOT have chicken wire appearance
162
what are groups of disorders caused by inherited defects in structural proteins that lend mechanical stability to the skin
epidermolysis bullosa
163
what is a common clinical feature of epidermolysis bullosa
ability to form blisters at site of pressure, rubbing, or trauma at or soon after birth
164
age of ppl with acne vulgaris? more common in m or f?
univeral in middle to late teenage years
m=f
165
what can cause acne vulgaris
1. induced or exacerbated by drugs
2. occupational exposures
3. conditions that favor occlusion of sebaceous glands
166
what is inflammatory acne
erythematous papule, nodules and pustules
167
what is noninflammatory acne
comdones: small papules with or without black central plug (oxidation of melanin pigmentation)
168
what age of ppl w rosacea? men or women
middle aged or beyond
greater in f
169
4 stages of rosacea
1. flushing episodes (pre-rosacea)
2. persistent erythema and telangiectasia
3. pustules and papules
4. rhinophyma
170
what is permanent thickening of nasal skin by confluent papules and prominent follicles
rhinophyma
171
development of ___ is associated with hypertrophy of sebaceous glands and follicular plugging by keratotic debris
rhinophyma
172
what is an inflammatory rxn in subcutaneous adipose tissue
panniculities
173
panniculitis primary affects what regions of adipose
1. lobules of fat
2. CT that separates fat into lobules
174
where does panniculitis mostly occur
lower legs
175
what is oorly defined, exquisitely tender, erythematous plaques and nodules that may be more palpated than seen; biopsy needed for diagnosis
erythema nodosum
176
what is erythema nodosum MOSTLY associated with
strep
177
can fever and malaise accompany erythema nodosum
yes
178
T/F: over the course of weeks, erythema nodosum lesions usually flatten and leave no clinical scars and no lesions develop
TRUE
179
what is OUTWARD panniculitis
erythemanodosum
180
is erythema induratum common?
no - uncommon, but greater in adolescents and menopausal women
180
what is INWARD panniculitis
erythema induratum
181
what causes erythema induratum
unknown but regarded as primary vasculitis of deep vessels supplying fat lobules of subcutis
182
erythema induratum can lead to what
fat necrosis and inflammation
183
is erythema induratum an erythematous, slightly tender nodule that usually ulcerates
YES
184
what are verrucae also called
warts
185
what are squamopoliferative lesions caused by HPV
verrucae (warts)
186
age range of ppl with warts
children and adolescents
187
where are warts present
> on hands; dorsal surface and periungal areas
188
what is multiple, grey-white to tan, flat to convex, 0.1- to 1 cm papules with a rough pebbly surface
verrucae (Warts)
189
how does warts transmission occur
involves direct contact between individuals or autoinoculation
190
are warts self limiting
yes - regressing spontaneously within 6 months to 2 years
191
what is a common, self limiting viral disease of skin caused by poxvirus
molluscum contagiosum
192
what age is mollusum contagiousm present
children and young adults
193
how is molluscum contagiosum spread
direct contact
194
where are molluscum contagiousum lesions present
skin and mucous membranes of trunk and anogenital reas
195
what are firm, often pruritic lesions, pink to skin-colored umbilicate papules, generally ranging in diameter from 0.2 to 0.4
molluscum contagiosum
196
what is a common superficial bacterial infection of skin
impetigo
197
what is highly contagious; frequently seen in otherwise healthy children and adults in poor health
impetigo
198
where is impetigo present on body
exposed skin, particularly face and hands
199
what bacteria causes impetigo
S. aureus
200
Erythematous macules with multiple small pustules; as pustules break, shallow erosions form, covered with drying serum giving the appearance of honey colored crust
impetigo
201
what happens if impetigo crust is not removed
new lesions form on the periphery of crust
202
how is impetigo treated
topical or systemic antibiotics
203
where is superficial fungal infection confined to
stratum corneum
204
what primarily causes superficial fungal infections
dematophytes (grow in soil and on animals)
205
what are the diverse lesions of superficial fungal infection
1. tinea capities
2. tinea barbae
3. tinea corporis
4. tinea pedis
206
___: > children, rare in infants and adults; > scalp; asymptomatic, patchy skin lesions associated with mild erythema, crust formation, scaling, and frequent hair loss
Tinea capitis
207
___: Infection of beard; adult men; uncommon
Tinea barbae
208
___: > all ages; common skin infection; predisposing factors: excessive heat and humidity and exposure to infected animals
Tinea corporis
209
___: affects 30%-40% of population at some point of life; diffuse erythema and scaling; nail infection (onychomycosis) produces discolored, thick, and deformed nails
Tinea pedis
