Cutaneous Drug Eruptions Flashcards
define
dermatological presentation of a reaction to a drug
when does this reaction resolve?
when the drug is withdrawn
risk factors
age
immunosuppression
presentation
rash urticaria pigmentation itch pain photosensitivity
diagnosis
history (consider drug most likely to cause eruption e.g. penicillin, time interval) phototesting biopsy patch test skin prick
when is skin testing not indicated?
serum sickness reactions (type 3) or T cell mediated reactions
why is skin testing not indicated in type 3 and 4 reactions?
can trigger Steven Johnson Syndrome (SJS), toxic epidermolysis necrosis (TEN) and DRESS (drug reaction with eosinophilia and systemic symptoms)
management
- discontinue drug if possible and use alternative
- topical corticosteroids
- antihistamines
- allergy bracelet
- yellow card scheme
different types
immunologically cell-mediated reactions (allergic)
non-immunological reactions (non-allergic)
exanthematous drug eruptions
urticarial drug reactions (IgE mediated after rechallenge)
pustular or bullous drug eruptions
fixed drug eruptions
phototoxic drug reactions
drugs that cause acneiform eruptions
glucocorticoids androgens lithium isoniazid phenytoin
drugs that cause acute generalised exanthematous pustulosis (AGEP)
antibiotics
CCBs
antimalarials
causes of drug-induced bullous pemphigoid
ACEIs
penicillin
furosemide
trigger for linear IgA disease
vancomycin
what type of reaction is exanthematous drug eruption?
T cell mediated delayed hypersensitivity (type 4)
presentation of exanthematous drug eruption
widespread symmetrical rash (can progress to a more serious systemic reaction)
