MSS-Week 3

Question 1

Layers of Epidermis

Answer 1

Cornified - contains anucleate corneocytes + filaggrin and ceramides
Granular - contains flattened keratinocytes and keratohyalin and lamellargranules
Spinous - contains keratinocytes
Basal - contains stem cells and melanocytes
Basement membrane

Question 2

Keratinization/Cornification

Answer 2

Stem cell-> keratinocyte-> separate from basement membrane-> migrate toward surface-> lose water content-> lamellar and keratinocyte granules form-> lose organelles-> corneocyte
28 days

Question 3

Pemphigus Vulgaris

Answer 3

autoimmune blistering dx
rare, affects elderly
autoantibody against desmoglein 1/3-> weakened desmosomes-> intraepidermal blistering
flaccid blisters --> erosions
Nikolski's sign+ (rubbing=sloughing)
can be fatal, tx w immunosuppressants

Question 4

Ichthyosis Vulgaris

Answer 4

Common autosomal dom with wide variability
mutation in profilaggrin-> defective cornified envelope
large fish scales, esp on shins
assoc with atopic dermatitis, allergic rhinitis, allergies, asthma

Question 5

SPF (sunscreen)

Answer 5

=MEDprotected/MEDunprotected

MED= minimal erythema dose (at 24hrs)

Question 6

Layers of Dermis

Answer 6

Papillary - superficial, interdigitates w epidermis, more cellular, fine loose collagen
Reticular - deep, fewer cells, coarse packed collagen

Question 7

ECM

Answer 7

Collagen - produced by fibroblasts, Col I most abundant, then Col III, more Col III during embryogenesis and healing
Elastic fibers - composed of microfibrils made of fibrillin and amorphous elastin
Ground substance - glycoproteins, proteoglycans, hyaluronic acid, water

Question 8

Marfan Syndrome

Answer 8

Mutations in fibrillin (auto dom)
variable
tall, thin, long fingers, scoliosis, flexible, stretch marks, myopia, aortic aneurism, mitral prolapse

Question 9

Ehlers-Danlos Syndrome

Answer 9

Inherited disorder of collagen synthesis/assembly
variable
elastic, fragile skin, flexible joints, scoliosis

Question 10

Morphea

Answer 10

Acquired autoimmune
localized sclerosis/thickening of collagen
erythematous and indurated plaques, slowly expand, can leave scars

Question 11

Systemic Sclerosis

Answer 11

Acquired autoimmune
generalized sclerosis
young/middle age women
Lots of sx and other systemic probs

Question 12

Panniculitis

Answer 12

Inflammation of subcu fat

Question 13

Erythema Nodosum

Answer 13

Acquired disorder of young women
reactive process, can be triggered by Strep infxn, medications, or other
tender, red nodules on shins

Question 14

Structures of Basement membrane zone

Answer 14

Hemidesmosomes (BP 230-plakin-organize cytoskeletal archetecture, BP 180-connects keratinocytes and cytoskeleton to dermal Col VII) - cell-ACM attachment
Lamina Lucida (BP 180)
Lamina Densa (Laminin 332, Col IV)- bridges BMZ
Sublamina densa (Col VII) - anchoring fibrils, epidermal-dermal adhesion

Question 15

Bullous Pemphigoid

Answer 15

Most common autoimmune bullous dermatosis
usually elderly
tense/stable blisters with serous content
antibodies against BP230 and BP180, causes subepidermal blisters
DIF-> linear staining on epidermal side of salt-split
tx: high potency steroids

Question 16

Mucous Membrane Pemphigoid

Answer 16

Usually elderly
recurrent blictering of mucous membranes and skin-> scars
antibody against BP 180
association with malignancies
DIF-> linear staining on dermal side of salt-split

Question 17

Epidermolysis Bullosa Acquisita

Answer 17

Rare autoimmune against Col VII
slight trauma elicits blistering and erosions
fibrosis of hands and feet
DIF-> stining on dermal side of salt-split

Question 18

Epidermolysis Bullosa

Answer 18

mutations in genes encoding for BMZ proteins
inherited skin fragility
slight trauma-> blistering and erosions
Epidermolysis bullosa simplex= keratins 5,14
Junctional EB= laminin 332 and BP180
Dystrophic EB= Col VII

Question 19

Macule

Answer 19

flat, non-palpable <1cm

Question 20

Patch

Answer 20

flat, non-palpable >1cm

Question 21

Papule

Answer 21

elevated or depressed, palpable, <1cm

Question 22

Plaque

Answer 22

elevated or depressed, palpable, >1cm

Question 23

Nodule

Answer 23

palpable, >1cm, more rounded surface than plaque

Question 24

Vesicle

Answer 24

fluid filled blister, <1cm

Question 25

Bulla

Answer 25

fluid filled blister, >1cm

Question 26

Pustule

Answer 26

pus filled blister

Question 27

Wheal

Answer 27

edematous papules and plaques = hives

Question 28

Telangiectasia

Answer 28

dilated blood vessels

Question 29

Erosion

Answer 29

open area, loss of epidermis

Question 30

Ulcer

Answer 30

open area, loss of dermis

Question 31

Fissure

Answer 31

linear ulcer

Question 32

Purpura

Answer 32

area of hemorrhage

Question 33

Petechiae

Answer 33

pinpoint purpura

Question 34

Scale

Answer 34

accumulation of cornified layer

Question 35

Crust

Answer 35

dried serum, pus, blood

Question 36

Lichenification

Answer 36

epidermal thickening, accentuated skin markings

Question 37

Induration

Answer 37

dermal thickening, firm

Question 38

Excoriation

Answer 38

linear erosion caused by scratching

Question 39

Nummular

Answer 39

coin-shaped

Question 40

Geographic

Answer 40

irregular border like continent

Question 41

serpiginous

Answer 41

wavy lines

Question 42

Annular

Answer 42

ring-like with central clearing

Question 43

Arcuate

Answer 43

curved

Question 44

Verrocous

Answer 44

looks like top of cauliflower

Question 45

Targetoid

Answer 45

looks like bulls-eye

Question 46

Reticulate

Answer 46

net-like

Question 47

Blaschkoid

Answer 47

follows ectodermal development lines

Question 48

Types of pilosebaceous units

Answer 48

``` Lanugo= fetal Vellus= fine Terminal= coarse, often darker ```

Question 49

Components of pilosebaceous unit

Answer 49

hair follicle and associated sebaceous gland hair bulb (inferior), isthmus (middle), infundibulum (upper) stem cells are in matrix of hair bulb

Question 50

The hair cycle

Answer 50

``` Anagen= growth, 2-6yrs Catagen= regression, 2-3weeks Telogen= resting, 3mo ```

Question 51

Telogen effluvium

Answer 51

large proportion of hair enters telogen phase simultaneously as a result of stressor hair is shed 3mo later

Question 52

Alopecia Areata

Answer 52

autoimmune, sudden development of round smooth patches of hair loss, course unpredictable Nail changes= pitting Tx: topical corticosteroids

Question 53

Anagen Effluvium

Answer 53

Hair loss as result of medications (chemo) | starts 2-3weeks after admin, regrows once stopped

Question 54

Sweat glands

Answer 54

Eccrine: distributed all over, innervated by postganglionic sympathetics, ACh Coiled thin portion in lower dermis, frains into long this duct with apical portion,, large clear cells secrete electrolytes and water, dark cells unknown function Apocrine: function unclear, localized to specific sites, secrete oily precursors to body odor

Question 55

Acne Vulgaris

Answer 55

increase in sebum production, increased corneocytes -> plugging of hair follicles (comedo) These comedos can rupture-> inflammation Also P. acnes G+ rod found deep in follicle-> inflammation Comodones: closed=whiteheads, open=blackheads inflammatory-> pustules, nodules, cysts, papules post-inflammatory hyperpigmentation Tx: topical retinoids, benzoyl peroxide, topical antibiotics, systemic antibiotics, contraceptives, isotretinoin

Question 56

Acne Rosacea

Answer 56

persistent erythema, acne-like sx | Tx: similar to acne vulgaris

Question 57

Vitiligo

Answer 57

autoimmune destroys melanocytes-> depigmented patches unpredictable course Tx: topical corticosteroids, UV phototherapy

Question 58

Oculocutaneous albinism

Answer 58

inherited genetic disorder usually in tyrosinase, defects in melanin production skin and hair, visual sx too, skin cancer

Question 59

Piebaldism

Answer 59

Rare autosomal dom, congenital patch of white hair and skin due to absence of melanocytes Stable (unlike vitiligo) speckled appearance

Question 60

Waardenburg Syndrome

Answer 60

Rare autosomal dom or res, achromia of hair, skin, congenital deafness, heterochromia irides, eyebrow hyperplasia, wide nasal root

Question 61

Melanocytic Nevi

Answer 61

benign proliferations of melanocytes well circumscribed with regular border, uniformly pigmented Junctional=dermal-epidermal junction, compund=also in dermis, intradermal=only in dermis (histo) Congenital: tend larger all have small risk of malignant transformation

Question 62

Ephelides

Answer 62

Freckles | marker of UV damage-> increased risk of melanoma

Question 63

Cafe-au-lait macules

Answer 63

CALM well-curcumscribed, uniformly light or dark macules or patches, appear in infancy or early childhood Multiple may be sign of neurofibromatosis

Question 64

Solar lentigines

Answer 64

tan to dark brown macule due to UV exposure | seen later in life, larger

Question 65

Dermal melanocytosis

Answer 65

blue-gray patches over lumbosacral region, larger, common in asians "Mongolian spots"

Question 66

Acanthosis nigricans

Answer 66

commonly manifestation of insulin resistance, associated w cancer brown velvety plaques on posteroir neck, axilla, groin

Question 67

Diabetic Dermopathy

Answer 67

seen in 30% of diabetics brown atrophic macules on shins marker of poor diabetes control

Question 68

Necrobiosis lipoidica diabeticorum

Answer 68

yellow-orange atrophic patches progressively expand, sometimes ulcerate shins of diabetics

Question 69

Thyroid disease effect on skin

Answer 69

Hyperthyroidism: fine, velvety, smooth skin, warm and moist Graves ds: pretibial myxedema- hyaluronic acid deposition, firm non-pitting shiny pink plaques Hypothyroidism: cold dry rough skin, alopecia of lateral 1/3rd of eyebrows

Question 70

Adrenal disease effect on skin

Answer 70

Cushing's-> skin atrophy, striae, fragility, purpura | Addison's: hyperpigmentation

Question 71

Systemic Lupus Erythematosus

Answer 71

pink scaly rash on face (malar/butterfly) also diffuse alopecia, ulcers, Raynaud, etc Tx: topical steroids, systemic immunosuppressants

Question 72

Discoid Lupus Erythematosus

Answer 72

=Chronic cutaneous LE | hyperkeratotic violaceous plaques on head and neck, heal with atrophic scars

Question 73

Dermatomyositis

Answer 73

autoimmune with inflammation of skin and muscle symmetric muscle weakness, photosensitive dermatosis Heliotrope rash: pink-purple upper eyelids w edema Gottron's papules: pink-purple flat-topped papules

Question 74

Sarcoidosis

Answer 74

Noncaseating granulomas in multiple organ systems, skin in 1/4 red-brown macules and papules on face around eyes and nose Lofgren's syndrome

Question 75

Dermatitis Herpetiformis

Answer 75

autoimmune blistering caused by hypersensitivity to gluten

Question 76

Neurofibromatosis Type I

Answer 76

autosomal dom caused by mutations in NF1 gene multiple cafe-au-lait macules plexiform neurofibromas= larger plaques with bag of worms feel

Question 77

Tuberous Sclerosis

Answer 77

autosomal dom disorder causes multiple benign tumors in all organs facial angiofibromas= telangiectatic papules on central face

Question 78

Sturge-Weber Syndrome

Answer 78

Congenital developmental disorder capillary malformation-> port wine stain on forehead at birth also seizures and glaucoma

Question 79

PHACE Syndrome

Answer 79

Hemangiomas of the face (large), other things too

Question 80

Psoriasis

Answer 80

Plaque= most common Guttate= numerous smaller legions, often strep trigger erythrodermic= generalized erythema pustular= broad patches of erythema and pverlying pustules often symmetric involvement of extensor elbows/knees can have psoriatic arthritis too Tx: topical corticosteroids

Question 81

Atopic Dermatitis

Answer 81

most common chronic inflammatory skin dx onset in infancy, associated with allergic rhinitis and asthma acute: edematous erythematous papules and plaques, may ooze Subacute: erythematous and scaly, crusted, less well defined than psoriasis Chronic: thickened with lichenification facial predominance, dry skin, pruritis is a prob Tx: topical corticosteroids, skin care, avoid triggers, also phototherapy and immunosuppressants and antihistamines

Question 82

Seborrheic Dermatitis

Answer 82

Mild inflammatory condition, variable infants: greasy, yellow scale on scalp,, self-limited adults: areas of high sebum production, pruritis, more diffuse and ill-defined than psoriasis Tx: infants: emollients, low-potency topical steroids,, adults: topical antifungals

Question 83

Lichen Planus

Answer 83

idiopathic inflammatory common in middle-age adults possibly autoimmune caused by drugs, HepC, vaccines small, polygonal, violaceous, flat-topped papules, pruritis, fine white lines (wickham's striae),, located on flexor surfaces can have oral involvement Tx: eliminate trigger, topical steroids and antihistamines, sometimes phototherapy and immunosuppressants

Question 84

Seborrheic Keratosis

Answer 84

common benign lesion, middle-age and elderly sharply delineated, round, flesh colored or brown-black warty plaques on trunk or face Some have FGF3 mutation Sudden appearance of multiple= Leser-Trelat sign= internal malignancy (adenocarcinoma of stomach) Hyperkeratotic papillomatous and verrucous epidermis Tx: nothing necessary, can remove if necessary

Question 85

Actinic Keratosis

Answer 85

=solar/senile keratosis common lesions, dysplastic (pre-neoplasia) result of UV exposure Some can become malignant rough, erythematous or yellow-brown scaly lesions surgical or medical destruction corneal layer is thickened w nuclei, dermis thickened blue-gray elastic fibers (solar elastosis)

Question 86

Squamous Cell Carcinoma

Answer 86

Common tumor due to sun in elderly SCC in situ is irregular shape, erythematous and scaly or crusted plaques Invasive tends to be nodular, variable scale, may ulcerate 5% go invasive, 30% of those metastatic removed with surgery full-thickness dysplasia

Question 87

Keratoacanthoma

Answer 87

A variant of SCC solitary pink or flecsh colored dome shaped nodule with central keratin plug grows rapidly over 2-10 week then stationary tends to involute spontaneously, but may cause extensive local damage, so treat aggressively

Question 88

Basal Cell Carcinoma

Answer 88

Most common malignant cutaneous neoplasm sun exposed elderly males patched/hedgehog pathway mutations papule with a pearly translucent edge w visible telangiectasia most are slow growing, non-aggressive, rarely metastatic Tx: surgery superficial type (in epidermis) or nodular type (dermis, basophilic with peripheral palisading)

Question 89

Dysplastic Nevi

Answer 89

Some potential for malignant transformation usually larger than acquired nevi, irregular in shape, uneven color, tend to be on non-sun exposed areas Dysplastic nevus syndrome: multiple dysplastic nevi, increased risk of melanoma and other cancer), CDKN2A gene Always junctional or compound (not intradermal)

Question 90

Melanoma

Answer 90

Most serious skin cancer, adults, 6th most common cancer mostly de novo striking variations in pigmentation, irregular/notched borders ABCDE: asymetry, border, color, diameter, evolution Some have germline CDKN2A mutation BRAF or NRAS mutations are common Tx: surgery, metastastasis=poor prognosis Breslow thickness= depth of penetration= predicts prognosis cells are large with abundant cytoplasm, dusty melanin, poorly formed nests, lack of maturation

Question 91

Types of Melanoma

Answer 91

Lentigo maligna: usually head and neck, in situ lesion present for years before tumor, sun damage Superficial spreading: most common, trunk in men, legs in women Nodular: high vertical growth rate, poor prognosis, trunk and legs Acral lentiginous: least common in white, most common in AA, asian, hispanic, palmar, plantar, subungal, older females

Question 92

Mycosis Fungoides

Answer 92

T-cell lymphoma, most common cutaneous lymphoid malignancy males 2:1, blacks 2:1 Patch stage: many years, ill defined patches of varying hue, fine scale, irregular in size and shape, random distribution on trunk Plaque stage: well-demarcated lesions, annular in shape, violaceous and scaly Tumor stage: red in color, tense shiny surface, maybe ulceration Proliferation of CD4+ T-cells, usually CD8-

Question 93

Sezary Syndrome

Answer 93

rare variant of cutaneous T-cell lymphoma erythroderma, blood involvement, poor prognosis generalized exfoliative erythroderma and tumor cells in peripheral blood

Question 94

Impetigo

Answer 94

``` superficial bacterial skin infxn usually Staph aureus small superficial vesicles, rapidly burst then thick yellowish dirty crust with margin of erythema mouth, nose, extremities warm, humid conditions Tx: topical antibiotics neutrophilic infiltrate ```

Question 95

Staphycoccal Scalded Skin Syndrome

Answer 95

toxin mediated exfoliative dermatitis phage group II, type 71 S aureus, exotoxins A and B intraepidermal splitting through granular layer, sudden onset skin tenderness, macular eruption, large easily ruptured bullae, desquamation in large sheets good prognosis in kids, bad in adults

Question 96

Cellulitis

Answer 96

diffuse inflammation of connective tissue expanding area of erythema, edematous and tender marked dermal edema and lymphatic dilation, diffuse neutrophils

Question 97

Erysipelas

Answer 97

Type of cellulitis elevated border, preads rapidly, usually old males, lower extremeties oral antibiotics

Question 98

Warts

Answer 98

HPV infection Verruca vulgaris: most common Verruca plana: flat wart on face or dorsal hands Verruca plantaris: on soles Verruca palmaris: palms typically spontaneously regress, or can destroy papillomatous hyperplasia of epidermis, prominant granular layer, irregular basophilic keratohyaline granules

Question 99

Condyloma Accuminatum

Answer 99

commonly caused by HPV 6, 11 trauma accompanying intercourse (genitals) single or multiple papular eruptions, pearly, filiform, fungating, cauliflower, plaquelike, can be smooth, verrucous, or lobulated marked acanthosis with broad exophytic growth, surface is hyperkeratotic and parakeratotic

Question 100

Herpes Simplex Virus (HSV)

Answer 100

HSV1= herpes labialis HSV2= herpes genitalis Diagnosis: Tzanck smear, PCR, biopsy usually self-resolving, can use antivirals epidermal acantholysis with multinucleated keratinocytes with glassy intranuclear inclusions, balloning degeneration

Question 101

Variella and Herpes Zoster

Answer 101

widespread vesicular eruption, successive crops of papules, vesicles, pustules, crusted lesions, healing lesions

Question 102

Molluscum Contagiosum

Answer 102

caused by DNA poxvirus, direct skin contact solitary or multiple dome-shaped umbilicated, waxy papules kids, head/neck/trunk/genitals inverted lobules, eosinophilic inclusion bodies in cytoplasm of keratinocytes above basal layer

Question 103

Scabies

Answer 103

caused by a mite papules and burrows on hands and feet papular eruption often excoriated, secondary bacterial infxn Tx: topical insecticide

Question 104

Dermatophytoses (Tinea)

Answer 104

fungus Epidermophyton: epidermal keratin Microsporum, Trichophyton: also hair presence of neutrophils, sandwich sign

Question 105

Tinea Versicolor

Answer 105

= pityriasis versicolor common superficial fungal infxn, tropical climates, young adults Malassezia multiple irregular areas of hypo/hyperpigmentation, circular and macular Tx: topical or oral antifungals spaghetti and meatballs

Question 106

Urticaria

Answer 106

=hives pink edematous papules and plaques migratory and individual lesions last less than 24hrs angioedema and anaphylactic shock can also occur IgE-mediated hypersensitivity, usually caused by upper respiratory infxn oral antihistamines

Question 107

Exanthematous Drug Erumptions

Answer 107

=morbilliform drug rashes Type IV hypersensitivity monomorphic macules and thin papules start on face and trunk, then extremities pruritic, low-grade fever onset 2-14days after drug initiation spontaneously resolve over 2 weeks Tx: supportative for pruritis, topical steroids and oral antihistamines

Question 108

Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS)

Answer 108

resembles exanthematous drug eruption, but associated with fever, facial edema, enlarged lymph nodes, arthralgias Ofen liver involvement, can be fatal systemic corticosteroids

Question 109

Erythema Multiforme

Answer 109

Target lesions with 3+ color zones and a dusky red/purple center arise abruptly on acral areas, last up to 2weeks usually infectious trigger (herpes simplex) self-resolves, can use systemic steroids if severe

Question 110

Stevens-Johnson and Toxic Epidermal Necrolysis (SJS/TEN)

Answer 110

severe, life threatening disorders usually preceded by prodrome of fever, malaise, upper respiratory sx painful red patches evolve rapidly to bullae and necrosis SJS30% mortality rate is high, esp from sepsis

Question 111

Vasculitis

Answer 111

inflammation and destruction of blood vessels, range of presentations

Question 112

Leukocytoclastic Vasculitis (LCV)

Answer 112

histologic diagnosis, multiple clinical presentations neutrophils are predominant inflammatory cell can be triggered by infections and drugs palpable purpura, usually legs

Question 113

Henoch-Schonlein Purpura

Answer 113

Small vessel vasculitis, usually kids leukocytoclastic vasculitis, but IgA immune complexes are more specific usually triggered by infections palpable purpura, esp buttocks and lower extremities self-limited, resolves of 2-4weeks