Usmle 3 Dermatology

Front 1

alopecia areata

Back 1

- well demarcated, non-scarred areas of hair loss
- AI mediated, suspect in those with other AI diseases; or young man with random well demarcated spot of balding in the non-androgen alopecia related areas
- often also see nail pitting
- tx: intralesional CS

Front 2

tinea capitis

Back 2

- young kids
- erythema, boggy, scaly, black, pustules, cervical LAD

Front 3

keratoacanthoma

Back 3

- common on cheek
- low grade malignancy similar to SCC
- solitary, firm, round, skin-colored or reddish plaque that develops into nodule with central keratin plug

Front 4

verruca vulagaris

Back 4

- looks similar to seborrheic keratosis

Front 5

BCC

Back 5

- usually red
- rare in age < 40

Front 6

seborrheic dermatitis

Back 6

- erythematous scaling plaques and patches w/ indistinct margins
- commonly on scalp, central face, ears, chest, back, axilla, pubic area
- may be secondary to malassezia furfur, but don't need fungal scrapings to dx
- young college guy --> HIV testing

Front 7

tinea versicolor

Back 7

- adolescents, young adults
- mildly pruritic
- hypopigmented, light brown, salmon colored macules
- topical antifungals

Front 8

treatment of acne during pregnancy?

Back 8

- cat B: topical azeleic acid or clindamycin, erythromycin
- cat C: benzoyl peroxide, sodium sulfacetamide
- cat D: AVOID oral tetracycline, retinoids

Front 9

sporotrichosis

Back 9

- fungus infx seen in outdoorsy people
- papular lesion over sight of innoculation --> ulcerates --> NON-purulent d/c
- spreads lymphatically --> oral itraconazole

Front 10

blastomycosis

Back 10

- inhalation
- acute PNA spreading to bone, skin, GU

Front 11

actinomycosis

Back 11

- only found in humans, not in the environment
- cervicofacial disease
- slow growing and destructive
- multiple abscesses, fistulae

Front 12

coccidiomycosis

Back 12

- inhalation
- chest pain, fever, cough, hemoptysis
- initial primary sx: erythema nodosum

Front 13

tx of herpes zoster

Back 13

- acyclovir for 5-7 days
- if rx w/in 48hours of eruption then can length and pain
- oral prednisone accelerates healing and decreases pain and useful in Bell's palsy but don't use in DM, glaucoma, HTN, etc)

Front 14

herpes zoster infectiousness

Back 14

- no contact precautions needed in community
- yes contact precautions if pt in hospital
- must hospitalize and isolate if immunocompromised or disseminated herpes zoster until lesions crusted over

Front 15

pressure ulcers

Back 15

- stage 1: blanching/erythema
- stage 2: partial loss of epidermis, dermis or both
- stage 3: may extend to fascia
- stage 4: very deep, full thickness to bone or muscle
- tx with moistened gauze

Front 16

hair loss in secondary syphilis

Back 16

- "moth-eaten" appearance, significant scarring

Front 17

pt with psoriasis

Back 17

- get skin biopsy to dx - hyperplasia, neutrophil infiltration, thin or absent granular layer

Front 18

tinea capitis

Back 18

- microsporum canis infection
- +Wood's UV lamp
- ddx trichophyton tonsurans infection with is (-) Wood's UV lamp

Front 19

lichen planus

Back 19

- immune mediated skin d/o
- skin, nails, mucosa (mouth, GU area)
- skiny, pruritic, polygonal shaped violacious papules with lacy pattern
- do punch biopsy, not skin scrapings: hyperkeratoic, acanthosis
- associated with liver disease so test for hep C

Front 20

drugs the exacerbate psoriasis

Back 20

- beta blockers, antimalarial, NSAIDs, ACE-I, lithium

Front 21

sun screen

Back 21

- reduces incidence of basal and squamous cell carcinoma, but not melanomas

Front 22

tinea versicolor

Back 22

- multiple small circular maculae in either white, pink, brown
- yeast infection
- common in summer
- tx terbinafine, clotrimazole, ketoconazole

Front 23

tx of pityriasis rosea?

Back 23

- oral erythromycin

Front 24

side effect of doxycyline?

Back 24

- photosensitizing agent --> bad sunburn

Front 25

side effect of isotretinoin?

Back 25

- hyperTG --> pancreatitis
- check TG, TC, LFTs before initiating and at least monthly

Front 26

porphyria cutanea tarda

Back 26

- painless blisters, increased fragility of the skin on dorsal surfaces of hands, facial hypertrichosis and hyperpigmentation
- triggered by ingestion of substances (Ethanol, estrogen (OCP))
- dx by elevated urinary uroporphyrins
- tx: phlebotomy or hydroxychloroquine

Front 27

dermatitis herpetiformis

Back 27

- pruritic papules and vesicles on the elbows, knees, buttockes
- secondary to gluten-sensitive enteropathy that may be subclinical

Front 28

impetigo

Back 28

- pruritic, honey-colored macules, vesicales, bullae on the face and other exposed parts
- staph or strep A

Front 29

pityriasis rosea

Back 29

- self-limiting, unknwon etiology
- single primary plaque with fine collarette scale
- fine, scaling papules and plaques in christmas tree distribution

Front 30

tretionin

Back 30

- reduces fine wrinkles, mottled hyperpigmentation, roughness of facial skin, appearance of brown spots

Front 31

Onychomycosis

Back 31

- must confirm with scrapings, if negative then culture
- tx with oral terbinafine or itraconazole; ketoconazole and griseofulvin are rarely used now b/c lengthy tx and adverse effects

Front 32

actinic keratosis predisposes to which cancer?

Back 32

- squamous cell
- it's a pre-malignant condition

Front 33

psoriasis

Back 33

- erythematous, well-defined plaques covered by thick silvery scales
- tx: for cosmetic purposes can rx topical high-potency corticosteroids = betamethasone (low potency = hydrocortisone for face area)
- tx if severe is methotrexate

Front 34

rosacea tx

Back 34

- topical metronidazole w/ or w/out course of oral abx
- if refractory try isotretinoin

Front 35

rosacea is associated with?

Back 35

- chalazion: granulomatous inflammation of eye gland -- painless, pea-sized nodule within eyelid

Front 36

endophthalmitis

Back 36

- corneal ulcers and ocular infections with pseudomonas, yersinia, mycobacterium

Front 37

tx of acne

Back 37

- first line is topical retinoid
- moderate or mild refractory is treated with topical retinoid and benzoyl peroxide or topical abx
- severe or mod refractory is tx with 1) topical retinoid, benzoyl peroxide, and topcial abx; or 2) systemic abx plus topical retinoid or benzoyl peroxide
- systemic abx are not typically used exclusively
- most severe: systemic abx and topical retinoid or benzoyl peroxide ---> no response then oral isotretinoin