11. Dermatology Flashcards Preview

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Flashcards in 11. Dermatology Deck (29):
1

Impetigo
-tx
-what if pen allergix

amox/1st gen cephalosporin

clinda

2

Acne tx approach

pyramid:

refractorry: isoreitinoin (get UPreg)
severe: Doxy/Erythromycin
inflamed pustulses: benzyoyl peroxide
comedones: retinoids, topical.

3

what 2 fungal infxns need oral tx?
-what if don't tx?
-danger of orals?

Hair/Nails needs orals x several months:

-tinea capitis--griseofulvin
-onychomycosis--terbinafine

-permanent hair loss if don't tx tinea capitis

long term oral can have hepatotox. Therefore, must confirm dx with KOH before starting oral tx

4

contact dermatitis:
2 forms

irritant and allergic

irritant: direct toxic chemical effect on skin (occupation related chemical)

allergic: nickel, poison ivy, latex, etc

5

what is stasis dermatitis

people with leg edema (venous insuff), get leg flaking, erythema, brown discoloration, scaling.

Don't bx, as non-healing ulcer may occur. Venous stasis ulcer may also be present.

6

pemphigus vs pemphigoid
-sxs
-dx
-tx
-population

pemphigus:
+ nikolsky's, oral involvement
bx shows tombstones
steroids, MMF, Rituximab, life threatening
Age 30-50

pemphigoid:
- nikolsky's, no oral
bx IF shows Ab to dermal-epidermal jxn
Age 70-80
steroids

7

Bullous skin diseases (4 to know):

1. pemphigus
2. pemphigoid
3. dermatitis herpetiformis
4. porphyria cutanea tarda

8

porhyria cutanea tarda
-when to suspect
-how to dx
-tx

-when you see bullae on skin-exposed surfaces only
-Dark urine. Flouresces 'coral red' under Wood's lamp. (urine uroporphyrins)

tx: avoid sun, Etoh , other triggers.

9

seborrheic dermatitis
-what is it
-tx

'super-dandruff.' (not seborrheic keratosis)

-cradle cap included

selenium shampoo

10

Psoriasis
-tx

1st step: UV light
topical steroids in flares

11

pityriasis rosea
-what is this
-what can it be confused with
-tx

-herald patch, progressing to salmon-colored lesions.

-can look like rash of syphilis. (syphilis has hands/soles, pityriasis does not)

-steroids, self limiting 6 weeks

12

drug rash
-how long after drug exposure
-appearance

-4-14 days after exposure
-pink, morbilliform

13

Pt with target-shaped lesions on palms, soles.

Think what other than erythema multiforme?

Also, what are causes of erythema multiforme? (3)

-syphilis

1. drug (esp cephalosporins)
2. HSV
3. mycoplasma

14

erythema multiforme/SJS/TEN
-what drugs can cause? (think 4 categories)

-sulfa
-PCN
-NSAIDs
-anticonvulsants

15

SJS vs TEN
-difference, how to know

2 things: body surface area, and Bx

SJS: <10% BSA, Bx shows basal cell degeneration

TEN: >30% BSA, full thickness necrosis

Bx also will find out SSSS

16

Pt with SJS/TEN: other than getting bx, do what (3)

-remove ALL meds, including steroids (can worsen!).
-Admit to burn unit
-give Clinda

17

SJS/TEN: how many days after drug exposure?

no correlation, could be days or weeks

18

melanoma
-mnemonic
-what to do if suspect?

ABCDE
asymmetry
border
color
DIAMETER >5mm
evolution

Wide excisional bx, punch bx if on face and suspicion low

19

Seborrheic keratosis vs melanoma

seborrheic keratosis (stuck on age spots, look like ugly moles)

-if present long time, unchanged, it is SK. however, if new or changing, do bx to r/o melanoma.

20

actinic keratosis: what is dz spectrum?

-do what for actinic keratosis

actinic keratosis
Bowen's dz (CIS)
SCC

pre-SCC, so do Bx. Do local ablation. If CIS/Bowen's resect. Can also do 5-FU, imiquimod

21

Pt says they had "SCC that went away on its own" on his hand, think what

Keratoacanthoma. looks like SCC but grow and regress spontaneously.

If you see it, do resection like SCC

22

Pt with patchy depigmentation on skin:
-what dx to think:
-how to dx
-tx

1. tinea versicolor.
-KOH prep--sphagethi meatballs
selenium shampoo.

2. vitiligo
-dx with Woods lamp
-steroids and UV light

23

Tuberous sclerosis:
-skin findings (3)

1. shagreen patch (raised collagen)
2. sebaceous adenomas (funny looking acne)
3. ash-leaf macules (hypopigmented, use Woods lamp)

24

salmon colored rash, think what dx
-tx

pityriasis rosea
-always check RPR
-tx with topical steroids, 6 weeks self limiting

25

Patchy alopecia: dx approach?

Make sure exisiting hair same length (otherwise trich). Think tinea capitis--do KOH prep.

If KOH-, think lupus, get ANA.

26

Eczema
-first tx?

topical steroids (hydrocortisone)

benadryl is adjunct

27

Post-strep GN
-what is time frame after infection?

3-6 weeks after impetigo

1-2 weeks after strep pharyngitis

28

Hypersensitivity types 1-4?

1. immediate Allergic reaction

2. Ab target antigens on tissue surfaces. eg Graves, Myasthenia gravis, ABO incompat. no rashes.

3. Ag/Ab complexes, depositing on tissues. eg RA, SLE, reactive arthritis

4. delayed, T cells. eg contact dermatitis

29

key words:

-Ab against hemidesmosomes
-Ab against desmoglein
-neutrophilic abscess in dermal papillae

-pemphigoid
-pemphigus
-dermatitis herpetiformis