Time to revisit the definition and clinical criteria for anaphylaxis?

Anaphylaxis represents the severe end of the spectrum of allergic reactions. A number of different definitions for anaphylaxis are currently foundin the literature (Table 1).[1-6]Manydefine anaphylaxis as a life-threatening reaction. However, data from large case series and patient registries have demonstrated that despite the fact thatthe vast majority of anaphylaxisreactionsare not treated appropriately with prompt administration of epinephrine/adrenaline, ingeneral this does not result in increased mortality or morbidity(such as hospitalization);[7-9]this observation is also consistent with national epidemiological datafor food anaphylaxis, which indicate that fatal anaphylaxis is a rare (but unpredictable) event.[10-12]Therefore, the majority of anaphylaxis reactions cannot be described as life-threatening in themselves,althoughdue to our inability to predict severity of reaction, [12]we emphasise that all anaphylaxis must be appropriately treated with intramuscular epinephrine/adrenaline. Both the descriptions used by the Australasian Society of Clinical Immunology and Allergy (ASCIA)[4] and National Institute of Allergy and Infectious Disease (NIAID)[5] refer to anaphylaxis as a serious allergic reaction, and acknowledge the spectrum of severity in terms of identifying the potential for anaphylaxis to be life-threatening