091914 cutanoues rxn patterns

Question 1

urticaria

Answer 1

hives
pink, edematous papules and plaques

MIGRATORY LESIONS
individual lesions last LESS THAN 24 HOURS

caused by IgE mediated immediate hypersensitivity

most cases are idiopathic. drugs cause only 10% of cases

Question 2

exanthematous drug eruptions

Answer 2

also called morbilliform (measles like) drug rashes

most common cutaneous drug eruption

type IV hypersensitivity

monomorphic macules and thin papules start on face and trunk then spread to extremities

usually pruritic

rxn limited to skin

onset is 2-14 days after drug initiation

Question 3

DRESS stands for

Answer 3

drug reaction with eosinophilia and systemic symptoms

Question 4

cutaneous eruption of DRESS resembles

Answer 4

exanthematous drug eruptions

Question 5

how is DRESS different from exanthematous drug eruptions

Answer 5

associated w fever

Question 6

what can you also observe with DRESS in addition to fever and exanthematous drug eruption like appearance?

Answer 6

facial edema

eosinophilia is characteristic but not present in all cases

Question 7

what is the most common site of systemic involvement for DRESS

Answer 7

liver

Question 8

why is DRESS more serious than exanthematous drug eruptions

Answer 8

it’s FATAL in 10% of cases

Question 9

hallmark skin finding of erythema multiforme

Answer 9

target lesions characterized by 3 or more color zones and a dusky red or purple center

Question 10

where does erythema multiforme appear?

Answer 10

acral areas

Question 11

what causes erythema multiforme

Answer 11

infectious (most commonly HSV) causes are responsible in 90% of cases

drugs in 10% of cases

Question 12

significance of Stevens-Johnson syndrome and toxic epidermal necrolysis and SJS-TEN overlap

Answer 12

these are severe, life threatening disorders

Question 13

what is SJS, TEN, SJS-TEN preceded by

Answer 13

fever, malaise, upper resp symptoms before the onset of cutaneous lesions

Question 14

skin findings of SJS, TEN, SJS-TEN

Answer 14

painful red patches evolve rapidly into bullae and areas of necrosis

Question 15

definition of SJS

Answer 15

epidermal detachment in less than 10% of body surface area

Question 16

SJS-TEN overlap definition

Answer 16

10-30% of body surface area has epidermal detachment

Question 17

TEN definition

Answer 17

greater than 30% of body surface area has epidermal detachment

Question 18

can erythema multiforme have blisters

Answer 18

yes, it can occur, but if it does, it’s circumscribed and involves less than 10% of body surface area

Question 19

most cutaneous vasculitides involve what?

Answer 19

small vessels with inflam centered around arterioles and venules in dermis

Question 20

how is diagnosis of leukocytoclastic vasculitis given?

Answer 20

through biopsy
when neutrophils are the predominant inflammatory cell seen

it’s a small vessel vasculitis

Question 21

what causes leukocytoclastic vasculitis

Answer 21

50%-idiopathic

infections
drug hypersensitivity (most commonly antibiotics)

Question 22

hallmark cutaneous finding of leukocytoclastic vasculitis

Answer 22

palpable purpura, typically more common on legs

Question 23

what other findings can you see with leukocytoclastic vasculitis?

Answer 23

urticarial lesions sometimes, but unlike true urticaria, they are fixed for more than 24 hrs

Question 24

Henoch Scholein purpura

Answer 24

small vessel vasculitis that predominantly affects children

Question 25

what do you see on biopsy of HSP?

Answer 25

leuklocytoplastic vasculitis, but IgA immune complexes are a more specific finding when direct immunofluoresence is done

Question 26

what causes HSP

Answer 26

infections

Question 27

skin findings of HSP

Answer 27

palpable purpura, especially on buttocks and lower extremities