Usmle Ck - Derm

Front 1

where does dermatitis herpetiforms occur? which Ab is it associated with?

Back 1

- extensor surfaces of knees, elbows, neck and scalp
- anti-endomysial

Front 2

erythema multiforme description and etiology?

Back 2

- symmetrical target lesions
- 2/2 HSV, systemic dz, drug illness

Front 3

bullous pemphigoid occurs where?

Back 3

- on flexor surfaces

Front 4

pathology of SCC? basal cell? HSV?

Back 4

- SCC: invasive cords of squamous cells with keratin pearls
- BCC: invasive cluster of spindle cells surrounded by palisaded basal cells
- HSV: Tzank prep ==> giant cells

Front 5

canker sores aka?

Back 5

- aphthous ulcers

Front 6

which derm dz is associated with parkinsons? also what else? tx?

Back 6

- seborrheic dermatitis, also in HIV
- tx is antifungal

Front 7

etiology of tinea versicolor? pityriasis rosea?

Back 7

- fungal, malassezia globosa
- herpesvirus 7

Front 8

poison ivy is which sensitivity?

Back 8

- allergic contact dermatitis
- type IV: cell mediated (need prior exposure)

Front 9

types of sensitivities?

Back 9

- type I: IgE mediated, allergen cross links 2 IgE molecules on one mast cell ==> atopy, urticara, anaphylaxis
- type II: Ab mediated: cell bound allergen binds IgG or IgM ==> activate complement ==> cell damage, e.g. immune hemolytic anemia, Rh hemolytic dz
- type III: immune complex mediated: allergen forms complexes with IgG or IgM ==> nonspecifically activates complement cascade = serum sickness, arthus rxn
- type IV: cell ediated or delayed hypersensitivity; e.g. Poison Ivy, allergic contact dermatitis

Front 10

when to use topical 5-FU?

Back 10

- tx skin conditions with rapid cell division: actinic keratoses, superficial BCC, bowen's dz, solar keratosis

Front 11

mupirocin?

Back 11

- topical abx totx superficial skin infx, e.g.MRSA colonization

Front 12

strawberry hemangioma vs cherry hemangioma?

Back 12

- strawberry, aka infantile hemangioma: bright red plaque = MC benign vascular tumor in children, regresses in 3-5 yrs
- cherry: MC benign vascular prolif in adults. Does not regress

Front 13

cavernous hemangiomas

Back 13

- at birth or later in life
- soft, blue compressible masses

Front 14

cystic hygromas

Back 14

- aka lymphangiomas: occur in neck, lobulated, compressible, transluminate

Front 15

tx of cellulitis with systemic sx?

Back 15

IV naficillin or cefazolin

Front 16

necrotizing ng fascitis?

Back 16

GAS or staph or both
- purplish discoloration with gangrenous change
- empiric abx should cover aerobic + anaerobic = amp, sublactam, clinda

Front 17

areas of skin that have lost pigmentation?

Back 17

- vitiligo, most likely genetic and associated with autoimminue against melanocytes
- thus associated with other autoimmune dz: perniciuos anemia, autoimmune thyroid (graves, thyroiditis) type I DM, primary adrenal insufficiency, hypopit, alopecia areata

Front 18

staph scalded skin syndrome

Back 18

- children 5-6 y.o.
- toxins ==> exfoliation, facial edema, perioral crusting, erythema, flaccid bullae
- tx with abx

Front 19

toxic epidermal necrolysi

Back 19

- more benign than staph scalded skin
- hx of taking sulfonamides, phenytoin, barbituates, NSAIDs
- see discrete macules, loose patches of skin, involves oral mucosa

Front 20

scarlet fever

Back 20

- group A beta-hemolytic strep
- red macules over generalized erythema

Front 21

erysipelas

Back 21

- hx of trauma or pharyngitis
- 2/2 strep
- small erythematous patch that progresses to red indurated, tense, shiny plaque overlaping skin streaking, lymphadenopathy
- tx PCN

Front 22

impetigo

Back 22

- bullae with honey covered crusts

Front 23

pt with suspicious lesion?

Back 23

1 step: excisional biopsy w/ no margins and through subQ fat
- 2nd: if malignant then 1 cm margin
- if 1 mm thickness then all done
- if >1mm thickness, sential lymph node biopsy

Front 24

flesh colored papules with central umbilication?

Back 24

- molluscum contagiosum
- increased in those with cellular immunodeficiency e.g. HIV

Front 25

complement deficiency?

Back 25

- C3 = recurrent pyogenic bacterial respiratory tract, sinus infx
- C5-C8 = Neisseria infx
- C1 esterase def: hereditary angioedema

Front 26

mole that has changed in size or is now symptomatic (itchy)

Back 26

melanoma

Front 27

lentigo simplex

Back 27

- round, oval macule with even pigmentation 2/2 melanocyte hyperplasia

Front 28

**bullous pemphigoid

Back 28

- IgG and C3 deposits at dermal eipdermal junction
- older pt with hx of months of urticaria, no oral lesions
- blisters in flexual areas
- precipitating factor: UV rays, NSAIDs, abx

Front 29

pathology of pemphigus vulgaris, cicatricial pemphigoid, herpes gestations, urticaria?

Back 29

- pemphigus vulgaris: igG deposits intercellularly in epidermis ==> flaccid bullae; involves mucous membrane
- cicatricial pemphigoid: igG in linear band at dermal-epidermal junction, mucous membrane, mouth, oropharynx, conjunctiva, genitals
- herpes gestations: C3 at BM, 2nd tri pregnancy
- urticaria: intradermal edema w/leuk infiltration

Front 30

which skin lesion is associated with turner, down syndrome?

Back 30

- cystic hygromas

Front 31

secondary syphillis skin lesion?

Back 31

- maculopapular involves palms and soles, involves mucous membrane

Front 32

steven-johnson syndrome vs TEN?

Back 32

- SJS: up to 10% skin involved
- TEN: >30% involved

Front 33

MCC malignant tumor of eyelid? MCC benign tumor of eyelid?

Back 33

- BCC tx is excision w/ microscopically controlled margin
- squamous papilloma = frond like lobular projection

Front 34

keratoacanthroma

Back 34

- rapidly growing volcano-like nodule w/ central keratotic plug

Front 35

macule that does not tan and doesn't appear scaly until you scape it? tx?

Back 35

- tinea versicoo
-tx selenium sulfide and ketoconazole

Front 36

tx of acne?

Back 36

- non inflammatory: topical retinoid
- mild inflammatoy: topical abx
- severe: oral abx
- never use cream based cleaners

Front 37

baby with symmetrical rash everywhere except on diapers

Back 37

- atopic dermatitis 2/2 decreased skin barrier function ==> allergens able to go deep ==> immune response
- tx: mild cleanser, thick bland emollients, NSAIDs

Front 38

exfoliative dermatitis

Back 38

aka erythrodoma
- prior derm condition e.g.psoriasis, atopic derm, sezary syndrome

Front 39

tx of tinea corporis?

Back 39

terbinafine

Front 40

pyoderma gangrenosum

Back 40

- ulcerative skin lesio w/ intital lesion that's bite like reation with small papule or pustule, painful

Front 41

icthyosis vulgaris

Back 41

normal skin that progresses to dry scaly skin, lizard skin

Front 42

MC eye lesion assocaited with pirmary biliary cirrhosis?

Back 42

- xanthomas and xanthelasmas
- soft yellow plaques = lipid filled macrophages

Front 43

tx for nodulocystic acne w/ scarring?

Back 43

- pustules and nodules
- oral isotretinoin

Front 44

red spots with bluish specks over buccal mucosa? how does it spread? complications?

Back 44

- measles
- maculopapular, starts on face to trunk/extremitites
- complications, PNA, vit A deficiency, bronchiectasis

Front 45

VZV description?

Back 45

starts on trunk, spreads peripherally
- rapidly dvlps into vesicles ==> scabs

Front 46

porphyria cutanea tarda

Back 46

- deficiency of uroporphyrinogen decarboxylase
- painless blisters, increased skin fragility on dorsal surfaces on hand, facial hypertrichosis, hyperpigmentation
- triggered by certain substances (estrogens in OCP, ehtnaol)
- dx: urinary porphyrin levels
- tx: for relief do phlebotomy, hydrochloroquine; interferon alpha if also hep C

Front 47

rubella

Back 47

- maculopapular rash on face, spreads to trunk, extremities, posterior cervical and posterior auricular lymphadenopathy, polyarthralgia

Front 48

miliaria

Back 48

aka heat rash, people in hot moist climates

Front 49

skin tag aka

Back 49

acrochordon

Front 50

chalazion

Back 50

- eye lid: painful sweling ==> nodular rubbery lesion
- chronic granulomatous condition 2/2 meibonian gland obsturction
- need histological exam to r/o malignancy and ddx BCC

Front 51

which med causes phototoxicity?

Back 51

doxycycline

Front 52

SE erythromycin?

Back 52

GI upset, juandice

Front 53

supparative hidradenitis?

Back 53

- chronic follicular occlusive dz, often axillary/groin
- painful nodules draining sinus tracts

Front 54

eczema herpeticum

Back 54

- primary HSV associated with atopic dermatitis
- typical hx: young kid dx with atopic dermatitis now with umbilicated vesicles over erythematous skin
- fever, adenopathy, life threatenting
- tx: acyclovir ASAP

Front 55

acute graft vs host dz?

Back 55

- common after bone marrow transplant
- sx: skin rash, intestinal involvement (diarrhea with blood), abnormal LFTs, jaundice
- path: donor HLA T cell activation
- note if activation of host T cells then host T cells attack donor marrow ==> no myelopoiesis ==> neutropenia ==> infx

Front 56

acanthosis nigracans in 30 vs 60 y.o.

Back 56

30 y.o.- check for SM
60 y.o. - check for GI malignancy

Front 57

pellagra?

Back 57

- niacin deficiency
- triad: dermatitis, diarrhea, dementia

Front 58

tx of dermatitis herpetiformis?

Back 58

- dapsone

Front 59

actinic keratoses?

Back 59

- hyperkeratosis in sun exposed areas of old people
- acanthosis = thickening of epidermis
- parakertosis = retention of nuclei in stratus corneum
- dyskeratossi = abnormal keratinization
- hyperkeratosis = thickening of stratum corneum
- 1% to SCC

Front 60

baby with scale erythematous lesions on scalp and face

Back 60

- sebhorrheic dermattiis
- chronic inflammatory papulosquamous dz in all age groups
- occurs on eyebrows, nasolabial folds, eyelashes, scalp
- tx: moiturizeres, antifungals
- if severe than think immunodeficiency
- if just head involved = tinea capitis