Algorithm to identify patients at low risk
for penicillin/beta-lactam allergy
Did this patient have any symptoms of severe systemic or cutaneous adverse drug reaction?
These include ANY of the following:
Mucous membrane involvement
Skin desquamation
Vasculitis
Arthritis/arthralgia
Lymphadenopathy
Ongoing, unexplained fever
Evidence of kidney or liver involvement
Generalized pustulosis
Yes they did have some of these symptoms
No they did not
Clinical pearls:
The photos below demonstrate some common features of severe systemic or cutaneous adverse drug reactions. Review of these photos with your patient may be instructive.
Conjunctivitis and desquamation in SJS
Vasculitic rash with target lesions
Lip involvement in SJS
Acute generalized exanthematous pustulosis
Lip involvement and desquamation in SJS
Early or mild vasculitic rash
Note subtle purple center to rash. This should later become brown-green-yellow as the hemaglobin breaks down. All of these lesions should last >24 hours. If they last less than 24 hours, this is not a vasculitis, it is urticaria multiforme reaction, and although looks impressive, can be treated as urticaria, which is NOT on this list as a severe reaction
Vasculitic rash and desquamation with SJS
Resolving vasculitic rash
note the brown-green-yellow coloration to some of the lesions, as the hemaglobin breaks down. A vasculitic rash like this would last a minimum of 5 days. If patients report they had this kind of rash, and it lasted less than 24 hours, this was not a vasculitic rash, but was rather urticaria multiforme. Although this looks impressive, urticaria multiforme can be treated as urticaria, which is NOT on this list as a severe reaction