DERM 1 Flashcards
immunological mediated reactions are what
non immunologically mediated reactions are what
allergic. not dose dependant
non allergic can be dose dependant
immunological mediated reactions type 1
type 2
type 3
type 4
- urticaria
- cytotoxic: phemphihous and phemphigoid
- immune complex mediated: purpura rash
- T cell mediated
acute gen exanthematous pustriosis (AGEP) is also caused what
who
symp
potential severe reaction
exanthemous, maculopapular, crorbilliform
most common. mild and self limiting. 4-21 days after drug
widespread asym rash, mucous membranes spared, itch and mild fever common
involvement of mucous membrane and face
facial oedema and erythema
widespread confluent erythema
fever, blisters, SOB, wheeze, purpura, arthlagia, lymphadenopathy
urticarial drug reactions is what
immediate IgE hypersensitivity after rechallange with drugs
exposure to drug before to get sensitised
fixed drug eruptions is where
symptoms
resolves how
caused by what
always at the same site. sometimes distal sites affected too mild - restricted to 1 lesion
eczematous lesion, papules, vesicular, urticaria, round/oval, hands, genitilia, lip, occasionally oral mucosa
resolves with persistent pigmentation when drug stopped
tetracycline, doxy, paracetamol, NSAIDs, carbamazepine
phototoxic drug acute chronic what is the wavelength of concern amiodarone thiazides CCBs tetra, amiodarone
skin and system toxicity and photodegredation
pigmentation, photo ageing, photo carcinogens
wavelength of concern UVA
amiodarone: immediate prickling with delayed erythema and pigmentation
thiazides: exaggerated sunburn
CCBs: exposed telengectasia
tetra, amiodarone: increased skin fragility
SJS
toxic epithelial necrolysis
other types 3
minor form of TEN
>30% of epidermal detachment
drug reaction with esoniphilia and systemic symp DRESS
drug induced billows pemphigoid - ACEI, penicillin, furosemide
linear IgA disease - vancomycin
ix for cutaneous drug eruptions
history and exam phototesting for phototoxic biopsy skin prick patch and photopatch - suspected atopic derm
type 1 hypersensitivity
type 2 and 3
type 4
type 1 skin contacts, inhalation, injection, ingestation IgE mediated
urticaria. skin prick if negative challenge test
IgG anf IgM
type 2: transplantation, haemolytic disease of newborn, blood transfusions
type3: skin testing - arthus reaction
type 4: T cell mediated onset after 24-48h direct skin contact airborne injection
metals (nickel, chromate), drugs
patch testing
contact allergic dermatitis what is it
cause
ix
specific delayed type 4 hs. spongiotic derm
chemicals, topical therapies, nickels, plants, hair dye
patch testing 48h then 96h
irritant contact derm is what
may overlap with what
where
non specific. spongiotic derm. non allergic
may overlap with atopic derm. implications for complications
often hands
seborrhoic eczema cause
symp
RF
treatment
malasezia yeasts
scaly rash on face, scalp, axillae
HIV, parkinsons
topical ketoconazole and topical steroids
lichen simplex cause
treatment
from rubbing own skin
avoids sun. low dose phototherapy. topical steroid/emmoliant
photosensitive eczema is what
treatment
rash in sun exposed areas
sun avoidance, suncream, topical eczema
aortic dermatitis assoc with symptoms chronic changes SA infection HSV infection
assoc with other atopic disease
dry red skin, flaky, itchy, borders poorly defined, flexural distribution
lichenification, excoriation, secondary infection
golden crust, weeping
monomorphic punched lesions
