Anaphylaxis is an important, potentially life-threatening paediatric emergency. Food is responsible for the majority of anaphylaxis cases in the paediatric population.
1 Egg, milk, peanuts and tree nuts are the most common food allergens in the preschool population; peanut and tree nuts are the most common allergen triggers in older children. There is a wide spectrum of allergic reactions to these allergens ranging from minor urticarial reactions to anaphylaxis, with the associated risk of fatality.
Anaphylaxis is managed via a two-pronged approach: first lifestyle modification to avoid the allergen and second the acute management of the anaphylactic event itself.
2–4 Those children who have had anaphylaxis, or who are judged to be at high risk of anaphylaxis, are prescribed adrenaline (epinephrine) autoinjectors.
5 These are to be carried on their person, or by their carers, at all times in the case of accidental exposure to the allergen(s) in question. This is important as, although uncommon with an estimated incidence of one episode per 10 000 children per year,
5 most accidental exposures and subsequent reactions tend to occur in community settings
1 and because of the typically rapid onset and progression of reactions, most young people and their families do not have immediate access to medical support when this is most required.
Despite being prescribed an adrenaline autoinjector and being shown the correct method of administration, many young people and/or parents still often report being unsure when to administer this treatment.
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7 They often worry whether the reaction is severe enough to warrant an injection of adrenaline or whether their child may come to harm if given unnecessary treatment.
8 There is evidence that there is often a delay in administering the prescribed medication in an emergency.
1 This delay in administering adrenaline may lead to increased morbidity and also increases the risk of fatality.
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10 Allergy services therefore often encourage children and families/carers to use their autoinjectors if there is any doubt regarding the severity of the allergic reaction. Given the risk of further reactions and the above-described concerns about when to administer emergency treatment, it is perhaps unsurprising that studies have found that food allergy can have a detrimental impact both on the children themselves and also on family quality of life.
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12 There is, however, as yet no clear evidence on how to improve clinical and/or psychological outcomes in this population.
In the light of the above factors, we hypothesise that: first, uncertainty about the likely severity of their child's reaction (ranging from no reaction to mild to life-threatening) on accidental re-exposure to the allergenic food in question and second, what a patient or carer must do if a reaction occurs, both contribute significantly to parental/child anxiety. We further hypothesise that this uncertainty could be ameliorated by real-time expert clinical guidance and support.
We propose therefore to test the effectiveness of giving parents and carers of children and teenagers with known food allergy, who are medically considered to be at sufficient risk of anaphylaxis that they have been prescribed and trained in the use of adrenaline autoinjectors, 24-h telephone access (intervention arm) or office-hour access (routine care arm) to expert advice from the clinical allergy service. We will advise parents/carers/teen patients randomised to the intervention arm to ring this clinician-staffed advice line if they or their child has an allergic reaction and they are unsure as to how to manage it. We postulate that the availability of this service will improve disease-specific quality of life compared with families randomised to the routine care arm who do not have this 24-h access. We also suspect that the allergic reactions that parents or families contact the allergy team about will be better managed as a result of the advice given. There is currently no service such as this available in Ireland or indeed worldwide. This is, as far as we are aware, the first ever randomised clinical trial of patient care in the field of anaphylaxis.
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