Dermatology Flashcards
Eczema appears as
Spongiosis and may progress to a lichenified stage
Types of eczema
Atopic dermatitis
Allergic contact dermatitis
Irritant contact dermatitis
Stasis dermatitis
Features of AD
Dennie-Morgan folds
Allergic salute
Periorbital darkening
Keratosis pilaris
Xerosis
Pityriasis alba
Post inflammatory hypo/hyperpigmentation
Palmoplantar hyperlinearity
Intracellular edema in epidermis
Spongiotic dermatitis
Acute> subacute> chronic
Perivascular chronic inflammation +/- eosinophils
Spongiosis
Complications of AD
Allergic contact dermatitis is a Type _ reaction
4 delayed hypersensitivity
Irritant contact dermatitis symptoms
Burning and pain
Allergic contact dermatitis symptoms
Very itchy
Latex allergy
Type 1 hypersensitivity reaction
Urticaria
Cross reactants: banana, avocado, chestnut, kiwi, passion fruits
Poison ivy/ poison oak
Patch testing is used for
Type 1 hypersensitivity reactions
RAST testing (IgE antibodies)
Prick testing
Stasis dermatitis (medial side) due to venous valvular insufficiency
Cellulitis
Bacterial infection of deep dermis and subcutaneous tissue
MSSA, MRSA, strep pyogenes
Papulosquamous disorders
Conditions characterized by erythema or viola cells coloration and scale
Well demarcated
(Psoriasis, seborrheic dermatitis, nummular dermatitis, pityriasis rosea, lichen planus, tinea corporis, secondary syphilis)
Psoriasis
Caused by genetic predisposition and environmental triggers
Other kinds of psoriasis
Psoriasis
Parakeratosis
Diminished granular layer
Thickening of epidermis
Psoriasis
Neutrophils in epidermis
Seborrheic dermatitis
Caused by Malassezia furfur
Associated with HIV, Parkinson’s disease, mood disorders
Yellow, flaky greasy scale
Lichen planus
Increased risk for SCC
May be associated with HCV
5 P’s (papules, purple, polygonal, puritic, peripheral)
Lichen planus
Dense band like lymphocytic infiltrate along dermoepidermal junction
Lichen planus
Pityriasis Rosea
Associated with HHV-6 and HHV-7
Begins as herald patch
Christmas tree distribution
Measles
Cephalocaudal spread
Koplik spots on buccal mucosa
Conjunctivitis, cough, congestion
Rubella
cephalocaudal spread
Red macules on soft pallet
Arthritis
Roseola
Rash starts as fever subsides
red macules on uvula/soft palate
High fever, febrile seizures
Pemphigus foliaceous
Autoantibody to desmoglein 1
Subcorneal
No mucosal involvement
Corn flake scale
Intraepidermal blister
Lacks tombstoning
+ immunoflourescence for IgG and C3
Pemphigus vulgaris
Autoantibody to desmoglein 1 and 3
Flaccid vesicles
+ nikolsky sign
Severe musosal involvement
+ immunoflourescence for IgG and C3
Tombstoning
Pemphigus vulgaris
Intraepidermal blister
Bullous pemphigois
Autoimmune blistering disease
BP180 and BP230
Tense bullae
Bullous pemphigoid
Sub-epidermal blister
Esinophil predominant
Linear IgG and C3 basement membrane staining
Dermatitis herpetiformis
Subepidermal blistering caused by gluten sensitivity
IgA antibodies to transglutaminase
Puritic papules on extensor surfaces
Dermatitis herpetiformis
Neutrophils collect in papillary dermis
IgA in basement membrane staining
Porphyria cutanea tarda
Subepidermal blister with no inflammatory infiltrate
Porphyria cutanea tarda
Subepidermal blister
Tinea versicolor
Spaghetti and meatballs
VZV
Nuclei with margination of chromatin
Molluscum contagiosum
Erythema multiforme
Drug eruption
HSV triggered
Targetoid or iris-like papules on palms, face, extremities
Vascular change
SJS
Frequent medications
+ nikolisky sign
Erythema multiforme
Keratinocyte cell death
Detachment of epidermis from dermis
Epidermoid cyst
Pilar cyst
Seborrheic keratosis
Melanoma in situ
Actinic Keratosis
Caused by UV
Erythematous macule/papule with gritty scale
Actinic Keratosis
Hyperkeratosis
Elastic fiber damage
Squamous cell carcinoma in situ
Erythematous/scaly macule/papule
Squamous cell carcinoma in situ
Invasive squamous cell carcinoma
Erythematous scaly papules and plaques
Invasive squamous cell carcinoma
Keratoacanthoma
Rapidly growing crateriform lesions
Non-aggressive
Basal cell carcinoma
Pink pearly papule with rolled borders and broad telangiectasias
Mutated PTCH
Nevoid basal call carcinoma syndrome
AD
PTCH
Multiple basal cell carcinomas, jaw cysts
Skin tags in children
Xoderma pigmentosum
AR
XPA
NER caused skin cancer
Increased sensitivity to UV radiation
Merkel Cell Carcinoma
Neuroendocrine carcinoma
San damaged skin
Merkel cell polyomavirus associated
Poorly differentiated
Resembles small cell carcinoma of lung
Closely packed cells with scant cytoplasm
CK20+
Skin adnexal tumors
Arise from cutaneous appendages (sweat glands, hair follicle, sebaceous glands
Spiradenoma/cylindroma
Sweat gland neoplasms
Cylindroma
Basaloid nests
Mutations in CYLD
Brooke-Speigler syndrome
Tricheoepithelioma
Tumor of germinative hair follicle
Trichilemmoma
Skin colored tumor originating from root sheath of hair follicle
Associated with Cowden syndrome (PTEN, 85% of women get breast cancer, colon polyps )
Sebaceous adenoma and sebaceoma
Sebaceous carcinoma
Non-description erythematous papules rapidly enlarge and ulcerate
Extra facial involvement associated with Muir-Torre syndrome (variant of lynch syndrome, AD mutation in MSH2)
Defects in DNA mismatch repair
Micro satellite instability
Micro cystic Adnexal carcinoma
Locally aggressive
Erythematous, indurated plaque/papule commonly on perioral
Dermatofriboma
On legs
Flesh colored, pink, hyperpigmented firm papulonodule
Associated with insect bites, nicks while shaving
Dermatofibroma
Dermatofibrosarcoma protuberans
CD34+
T(17;22) COL1A1-PDGF beta
Dermatofibrosarcoma protuberans
Extensive infiltrates in dermis/subcutis
Neurofibroma associated with Neurofibromatosis type 1
AD mutation in NF1
Neurofibroma
bland spindle cells with wavy curvilinear nuclei
Some mast cells
Pale eosinophils
Cherry angioma
Infantile hemangioma
Angiosarcoma
Post radiation after breast cancer
Mycosis Fungoides
CD4+ helper T cell
Sezary syndrome (blood involvement, severe puritis)
Mycosis fungoides
Solar Lentigo
Sun damage
Precursor of seborrheic keratoses
Darken with UV exposure
Melanoma in situ
Lentigo simplex
Not induced or darkened by UV exposure
Lentigo Simplex
Melanocytic nevus
Caused by BRAF V600E or NRAS mutations
Can be various different types
Congenital melanocytic nevus
NRAS mutation
Halo nevus
Halo nevus
Blue nevus
Mutations in GNAQ and GNA 11
Blue nevus
Proliferation of dendritic melanocytes
Spitz nevus
HRAS mutation
Pigmented spindle nevus
NTRK gene fusion
Dysplasitic nevus
Sporadic nevus marked as markers of melanoma
Actual Lentiginous melanoma
Common in darker skin
Mucosal melanoma
Lips
Genitals
Lentigo maligna
“Sunspots” that have been there forever
Melanoma mutations
CDKN2A
BRAF NRAS
KIT
TERT
PTEN
Melanoma growth phases
Radial- lateral extension along epidermis
Low risk of metastasis
Vertical- more invasive
Breslow thickness
Used for prognosis