Are the dangers of childhood food allergy exaggerated?

NO The acquisition, preparation, and consumption of food are fundamental and unavoidable parts of life. Retrospective and prospective case series show time and again that food allergy can be fatal for some people, at a time and place they cannot predict or avoid (fig 1).^1-3 Food allergy is the most common cause of anaphylaxis outside a hospital setting.² Population based studies show that up to 6% of preschool children have had allergic reactions to foods and 2% of adults may be affected by IgE mediated allergies.⁴ Food allergy is at least as common as epilepsy. In the United Kingdom, the government says that organ specific specialties have adequate resources to provide allergy care,^5-7 but we would not be having this debate if this approach worked well. The UK is the only developed country that uses this system of service provision for allergy.

Fig 1.

Food allergy can strike unpredictably

Credit: AARNOUD HUISSOON, BIRMINGHAM

Allergic reactions to food are easy to treat, but the treatment is not always successful.² The uncertainty of predicting future risk (or safety) is unsettling for families of children with allergy and doctors who deal with such families. It is hard to live with the uncertainty about the timing and outcome of allergic reactions.⁸,⁹ Much of the anxiety relates to the lack of confidence that families have in their family doctors, who may not be very knowledgeable about allergies, or in nursery and school staff who may encounter the child while he or she is having an allergic reaction.¹⁰ It is my view that we need more medical training in allergy to meet the need that clearly exists for support of families and their primary care doctors.⁵

What foods cause allergy?

Any food that contains protein can cause allergy, but the list of foods that cause serious allergic reactions in children is remarkably short—only eight foods or food groups account for more than 90% of immediate allergic reactions (box).⁴ Many of these foods are staples that are difficult to avoid.¹¹,¹² Strategies of avoidance and appropriate family and medical responses need to be in place.

Is food allergy dangerous?

Food allergy kills people. If we accept this fact then we must look at the uncertainty surrounding food allergy that led to the charge of exaggeration. An allergic reaction itself is a traumatic experience—whether mild, moderate, or severe—and should be avoided. No biological markers are available to predict who will or will not have anaphylaxis in the future, so even experts cannot accurately predict a person's future risk. The “who, when, and where” of a future severe or fatal reaction are impossible to prove. This is an area of profound medical uncertainty.¹³

The prediction of who is and who is not at risk of a severe food allergic reaction is more of an assessment than a decision, and this assessment should focus on the role of asthma and a history of having previous severe reactions.¹ However, a prospective study of reported deaths due to allergy in the UK showed that only 20% of people who died of food allergic reactions had had a severe reaction in the past.²,³ None the less, patients who have had severe reactions in the past are more likely to have severe reactions in the future. Expert assessment and integrated management plans can minimise but not eliminate such risk.¹⁴,¹⁵ Data on severe allergic reactions in children who survived in the UK have been criticised by national and international experts in the field owing to the designs of the studies and over-restrictive case definitions which led to a significant underestimate of the incidence of severe allergic reactions to food in children.^16-18

Food allergy is dangerous in the wrong hands

People with allergy have the right to have their condition recognised and dealt with appropriately. Non-expert management can lead to unjustified exclusion diets, to justified diets being kept in place too long, to inappropriate social exclusion, and to malnutrition.¹⁹

Foods that cause more than 90% of IgE mediated allergic reactions in children

• Milk

• Eggs

• Peanuts

• Tree nuts and seeds

• Fish

• Shellfish

• Soya

• Wheat

Although there are worries that the provision of autoinjectors may increase anxiety, I know of no evidence to support this notion. My experience is precisely the opposite, and this view is supported by the literature.¹⁰,¹⁵ However, food allergy does cause anxiety (fig 2), and the doctor's approach to the problem may increase this anxiety. Even a mild allergic reaction may reduce a patient or parent's self confidence in dealing with allergy, whereas successful management will-increase the patient and their family's perception of control and reduce anxiety. Anxiety can be minimised by expert review and support. We just don't have enough experts.

Fig 2.

A young boy having a moderately severe allergic reaction, with angio-oedema, urticaria, and obvious anxiety

Credit: MEDICALMEDIAKITS.COM

Recommended websites

National

Anaphylaxis Campaign (www.anaphylaxis.org.uk) British Society of Allergy and Clinical Immunology (www.bsaci.org)

International

European Academy of Allergology and Clinical Immunology (www.eaaci.org)

Food Allergy and Anaphylaxis Network (www.faan.org)

American Academy of Allergy Asthma and Immunology (www.aaaai.org)

Proper management in allergy clinics means that most patients never have to use adrenaline kits, but it is wrong to say that the kits are not needed.¹⁴,¹⁵,²⁰ The prescription of such kits without training and support (for instance in primary care before review at an allergy clinic) is probably also “dangerous” and may cause distress. The argument about with whom the “burden of proof” lies betrays a fundamental misunderstanding of the management of allergy risk. Nobody is advocating “more general use” of adrenaline. What is advocated is increased availability of adrenaline kits for people who might need to use them.

The management of anaphylaxis is more than management of the event itself.⁸ It involves integrated and collaborative interaction with families to empower them and facilitate normal social activities, which will hopefully engender normal social development in the children.

Summary

Food allergy is here to stay. The disease is a killer (though rarely); it can erode or inhibit normal formative experiences in childhood, and it impairs a child's quality of life. The hazard of allergen exposure is considerable even if the risk of such exposure is low. Allergy is rarely viewed without prejudice in local health economies in the UK, despite its low cost and its place at the interface of community and hospital services. Let's get allergy services out of the academic centres and into the community, which is where food allergy is really “dangerous.”

Summary points

Food allergy is common—2% of adults and up to 6% of preschool children are affected

Deaths are rare but other reactions are almost inevitable over time

No tests are available to predict clinical severity

Management consists of empowering patients and providing rescue drugs

Delay in use of these drugs is associated with a worse outcome in severe reactions

These drugs are rarely needed by patients who attend recognised allergy clinics but cannot be withheld because of the medical uncertainty surrounding allergy