MSK/Derm VI

Question 1

impetigo

Answer 1

superficial skin infection

staph aureus
strep pyogenes

honey color blister

bullous - caused by staph aureus

Question 2

cellulitis

Answer 2

infection deep dermis and subQ

strep pyogenes
staph aureus

Question 3

erysipelas

Answer 3

infection - upper dermis and lymphatics

strep pyogenes

well defined demarcation infected and normal skin

Question 4

abscess

Answer 4

often staph auresus - methicillin resistant

Question 5

necrotizing fasciitis

Answer 5

deep tissue injury

strep pyogenes

crepitus - methane and CO2 production

Question 6

staph scalded skin syndrome

Answer 6

destroy keratinocyte attachment in stratum granulosum only

fever, rash, sloughing upper layers epidermis

newborn and children

Question 7

toxic epidermal necrolysis

Answer 7

destroys epidermal-dermal jxn

Question 8

herpes skin infection

Answer 8

HSV1 and 2

finger - whitlow

Question 9

molluscum contagiosum

Answer 9

umbilicated papule - poxvirus

Question 10

hairy leukoplakia

Answer 10

white painless plaque tongue - cannot scrape off

EBV mediated

Question 11

leukoplakia

Answer 11

not hairy

on side of tongue

is precancerous

Question 12

thrush

Answer 12

oral through - scrapable

Question 13

pemphius vulgaris

Answer 13

IgG Ab - desmoglein - of desmosome

intraepidermal bullae - acantholysis

positive nikolsky sign - separation with stroking

IF - Abs around epiermal cells in reticular pattern

Question 14

bullous pemphigoid

Answer 14

IgG Ab - hemidesmosome - basement membrane

tense blister - with eosinophils

IF - linear pattern - epidermal/dermal junction

negative nikolsky sign

Question 15

dermatitis herpetiformis

Answer 15

extensor surfaces
IgA - at tip of dermal papillae

celiac association

Question 16

erythema multiforme

Answer 16

infection, drug, cancer, autoimmune disease

Question 17

SJS

Answer 17

fever, bulla, necrosis, sloughing skin, high mortality

often mucous membranes

adverse drug rxn

Question 18

toxic epidermal necrolysis

Answer 18

> 30% of body surface

severe SJS

fever, bulla, necrosis, sloughing skin, high mortality

Question 19

acanthosis nigricans

Answer 19

flexor region
-hyperpigmented

hyperinsulin
visceral malignancy

Question 20

actinic keratosis

Answer 20

premalignant

to SCC - proportional risk to degree of epithelial dysplasia

Question 21

erythema nodosum

Answer 21

inflammation of subQ fat - anterior shins

sarcoid, coccidio, histo, TB, strep, leprosy, crohn

Question 22

pityriasis rosea

Answer 22

heraly patch - followed by christmas tree distribution

self resolving 6-8 weeks

Question 23

sunburn

Answer 23

UVA - tanning and photoaging

UBV - sunburn

Question 24

BCC

Answer 24

MC skin cancer

rare mets

pink pearly nodule
or flat nonhealing ulcer

palisading nuclei

Question 25

SCC

Answer 25

2nd MC skin cancer

precursor - actinic keratosis

Question 26

keratoacanthoma

Answer 26

variant SCC - grows rapidly but may regress

Question 27

melanoma

Answer 27

risk of mets
S-100 tumor marker

sun exposure

depth of tumor - risk of mets

ACBDE
D - 6mm

Question 28

types of melanoma

Answer 28

sueprficial spreading
nodular
lentigo maligna
acral lentiginous

Question 29

vemurafenib

Answer 29

BRAF kinase inhibitor

benefit in nonrescetable melanoma with BRAF V600E mutation