Dermatologic Disease Flashcards
Lasts days to weeks, includes inflammation and edema, is self limited or chronic
Acute inflammatory Dermatoses
(Urticaria and Eczema)
Type I hypersensitivity rxn
allergic rxn where mast cell granulation leads to erythema and edema
Urticaria (Hives)
Dermal microvascular hyper permeability / increased vascular permeability
Urticaria
Small pruritic papules to large erythematous plaques
Urticaria
Wheals or plaques
Urticaria
Pruritic erythematous papules - possible vessicles that ooze and crust
Eczema
Turns into raised scaly plaques
Eczema
5 things Eczema can be due to
allergy
defect in keratinocyte barrier
drug hypersensitivity
UV light
physical/chemical irritant
Allergic contact dermatitis fits under this category
Eczema
Environmental agent that reacts with self-proteins creating neoantigens that sensitizes T cells . On re exposure, memory CD4+ T cells are activated and release cytokines that recruit inflammatory cells and cause epidermal damage
Allergic contact dermatitis
Apparent after months/years. Skin = rough due to thick scale and shedding
Chronic inflammatory dermatoses
(Psoriasis)
Increased risk for heart attack and stroke
Psoriasis
affects arthritis patients
Psoriasis
Pink to salmon colored plaque covered by a silver scale
Psoriasis
Elbow, knees, scalp
Psoriasis
Severe complication of Psoriasis
Psoriatic arthritis
Pinpoint bleeding upon scratching scale off lesions
Psoriasis - Auspitz sign
Creating of lesions by scratching and leaving a trail
Psoriasis (not specific to it) - Koebnerization
TNF antagonist as treatment
Psoriasis
Describe the autoimmue response of Psoriasis
T-cell mediated inflammatory disease
T-cells release cytokines –> TNF α –> proliferation of keratinocytes –> formation of thickened plaques
2 infectious dermatoses
fungal -
bacterial -
Fungal = Superficial dermatophytes
Bacterial = Impetigo
Causes focal alopecia
Tinea capitis
Ringworm
Tinea corporis
Yeast that infects intertriginous zones
Candida
Things that increase risk of candida
Steroids
Antibiotics
Diabetes
Immunosuppression
What bacteria causes Impetigo
Strep. Pyogenes
Staph. aureus
Fragile vesicles to flaccid bullae
Impetigo
Children, crowding, poor hygiene, hot/humid
Impetigo
Honey colored crust
Impetigo
May resemble exfoliative cheilitis
Impetigo
May resemble recurrent herpes simplex
Impetigo
May resemble child abuse
Impetigo
Treatment = mupirocin
Impetigo
Hyperpigmented skin
Acanthosis Nigricans (AN)
Velvety skin
Acanthosis Nigricans (AN)
axilla, groin, or back of neck
Acanthosis Nigricans (AN)
Malignant Acanthosis Nigricans (AN) is associated with
internal GI malignancy
benign Acanthosis Nigricans (AN) is associated with
endocrinpathies or syndromes
Drug ingestion (insulin)
Oral lesion of Acanthosis Nigricans (AN)
papillary lesion of lips and tongue
associated with internal malignancy
Slow growing, fluctuant/rubbery nodule filled with keratin
Epidermoid cyst
On face and neck from hair follicles
Epidermoid cyst
Yellowish to white normal skin appearance
Epidermoid cyst
Tan-brown to black
Seborrheic keratosis
well-demarcated plaques
Seborrheic keratosis
stuck on, dirty candle wax, dried mud on brick wall
Seborrheic keratosis
basal cells that produce keratin
Seborrheic keratosis
variant of Seborrheic keratosis, multiple small dark papules on cheek
Dermatosis papulosa Nigra
With Seborrheic keratosis, if hundred appear suddenly
Leser-Trelat (sign of internal malignancy)
Premalignant Chronic sun (UV light)
Actinic Keratosis (AK)
On vermillion zone
Actinic Keratosis (AK)
Usually 6-8 lesions
Actinic Keratosis (AK)
Scaly plaque - sandpaper texture
Actinic Keratosis (AK)
Hyperkeratosis histologically
Actinic Keratosis (AK)
Epithelial dysplasia histologically
Actinic Keratosis (AK)
solar elastosis histologically
Actinic Keratosis (AK)
Sun-induced cancer from existing Actinic Keratosis
Squamous Cell Carcinoma
Fleshy, firm nodule, keratinized, crusty or ulcerated surface
Squamous Cell Carcinoma
Rare to metastasize
Basal Cell Carcinoma
From basal cells of epidermis or germ cells in hair follicles
Basal Cell Carcinoma
Most common skin cancer
Basal Cell Carcinoma
History of chronic skin exposure
Basal Cell Carcinoma
Middle 1/3 of face
Basal Cell Carcinoma
2 main subtypes of Basal Cell Carcinoma
Noduloulcerative (most common)
Sclerosing
Papule with central ulceration and rolled pearly white border
Basal Cell Carcinoma - Noduloulcerative
Lack of skin structure (hair)
Basal Cell Carcinoma - Noduloulcerative
Rodent ulcer
Basal Cell Carcinoma - Noduloulcerative
mimics scar tissue although patient never had an injury
Basal Cell Carcinoma - sclerosing
Histologically, basaloid cells “drop off” the basal cell layer
Basal Cell Carcinoma
Histologically can be similar to ameloblastoma
Basal Cell Carcinoma
First option treatment for Basal Cell Carcinoma
Mohs Surgery
Least common of the 3 skin cancers
Melanoma
75% of deaths due to skin cancer
Melanoma
Can be UV induced and non UV induced
Melanoma
Non UV melanomas have __ mutations
KIT
Can have a hereditary predisposition
Melanoma
Germline mutations in CDKN2A gene
Melanoma
UV induced melanomas have a __ mutation
RAS/BRAF
p16 inactivation leads to
vertical growth of Melanoma
p53 mutation leads to
metastasis of Melanoma
Most common type of Melanoma
Superficial spreading
this type of Melanoma occurs on Back, Arms, Neck and Scalp
superficial spreading
radial phase lasts months to years before vertical phase
superficial spreading
This type of melanoma occurs in malar skin or elderly
Lentigo Maligna
Expands rapidly over 10-15 years before vertical growth
Lentigo Maligna
Type of melanoma unrelated to skin cancer common in black and asians
Acral Lentiginous
Short radial growth before invading
Acral Lentiginous
On fingers and toes
Acral Lentiginous
Most mucosal melanomas are this type
Acral Lentiginous
Elevated and fast growing melanoma that is unrelated to sun exposure
Nodular
No radical growth, starts as vertical growth
Nodular
worst melanoma prognosis
Nodular
ABCDE’s tell you if its
Melanoma
(Asymmetry, borders, color, diamter >6mm, evolution)
Best form of prognostic indicator for melanoma
Brewslow tumor thickness
Any benign congenital or acquired neoplasm of melanocytes
Melanocytic Nevi (common moles)
Mutation in BRAF or RAS
Acquired Melanocytic Nevi
<6 mm
Acquired Melanocytic Nevi
flat lesion with uniform color that elevates or fades with age
Acquired Melanocytic Nevi
malignant transformation is rare
Acquired Melanocytic Nevi
Sporadic or familial RAS or BRAF mutation
Dysplastic Nevi
Larger than aquired nevi
Dysplastic Nevi
May have hundreds
Dysplastic Nevi
On sun exposed and not sun exposed skin
Dysplastic Nevi
when is there an increased risk for melanoma with Dysplastic Nevi
with there is more than 10
macules or plaques with a pebbly surface
Dysplastic Nevi
Variable pigmentation and irregular borders
Dysplastic Nevi
more stable over time <6mm vs evolves / changes over time and >6mm
Dysplastic Nevi vs Melanoma
2 benign melanocytic skin lesions
Ephelis / ephelides (freakles)
Actinic lentigo
Brown macule, increased pigment with sun exposure
Ephelis / ephelides (freakles)
Normal number of melanocytes
Ephelis / ephelides (freakles)
Brown macule on dorsal of hand and face
Actinic lentigo
linear increase of melanocytes in basal layer
Actinic lentigo