Letter to the editor. Two major phenotypes of sulfite hypersensitivity: asthma and urticaria

Hypersensitivity Reactions to Food Additives-Preservatives, Antioxidants, Flavor Enhancers

There have been reports of food hypersensitivity reactions to food additives (HFA) for many years. The mechanisms of HFA and their frequency are difficult to precisely define, as most of the data come from outdated studies with poor methodology. In 2020, the European Food Safety Authority completed a review of additives, examining their influence on the occurrence of HFA, but did not include all of them. The aim of this review is to systematise knowledge about selected groups of food additives (FAs) and the HFA induced by them. We also briefly discuss the issues of diagnosis and therapy in this disease. FAs are commonly used in prosscessed foods, but HFA appears to be a rare phenomenon. Identification of the FA responsible for hypersensitivity and its treatment is difficult. Diagnosis is a challenge for the clinician and for the patient. A food diary is a helpful diagnostic tool. It allows diet therapy to be monitored based on the partial or complete elimination of products containing a harmful additive. An elimination diet must not be deficient, and symptomatic pharmacotherapy may be necessary if its application is ineffective. Taking all this into account, we conclude that it is necessary to conduct randomised multicentre studies based on the double-blind placebo control protocol in this field.

Allergy to food additives

PURPOSE OF REVIEW

To provide an update of the studies concerning the diagnosis and management of food additives allergy.

RECENT FINDINGS

Additives improve specific characteristics of food products, but they may induce allergic even life-threatening reactions. Physical examination and medical history are basic to assess specific in-vivo and in-vitro tests. The only treatment for allergic patients consists in avoiding the food containing culprit additives. High-risk patients should be able to recognize severe reactions and self-manage them.

SUMMARY

The prevalence of adverse reactions to food additives is low, and it may depend on comorbidities, like asthma or chronic idiopathic urticaria. Food labels may help the correct identification of ingredients. Natural additives like spices should cause immediate reactions because of a pollen-sensitization or panallargen proteins presence. Additive-free diets may help the patient care, but the authors suggest assessing an oral food challenge with the culprit substance if there are no contraindications.

Asthma phenotypes based on health services use for allergic diseases in a province-wide birth cohort

BACKGROUND

Many previous studies on asthma phenotypes were conducted in selected clinical populations and overlooked changes throughout the life course.

OBJECTIVE

To identify asthma phenotypes based on use of health services for allergic diseases in 3 life periods and document transitions among phenotypes across life periods.

METHODS

In a population-based cohort of 78,211 individuals born in 1974 in the province of Québec, Canada, we documented medical visits and hospitalizations for asthma and other allergic diseases until 1994. Phenotypes based on clusters of health services use in childhood (8-12 years of age), adolescence (13-17 years of age), and young adulthood (18-20 years of age) were identified using a hierarchical method among 9,989 individuals (12.8%) who had at least one health encounter for asthma during follow-up. Population-level probabilities of transitioning among phenotypes were estimated in the full study population.

RESULTS

In the subset with asthma, 6 phenotypes were identified during both childhood and young adulthood and 7 during adolescence. The most common phenotype was no asthma or allergic diseases: 58% in childhood, 42% in adolescence, and 54% in adulthood. The second most common was the mild asthma and no allergic diseases phenotype, representing 36%, 31%, and 21%, respectively, in these 3 periods. In the study population, 87% of the individuals remained in the no asthma phenotype group during the follow-up. Most individuals in the asthma phenotypes transitioned over time.

CONCLUSION

Our study uniquely contributes to a better understanding, at the population level, of the manifestations and transitions in asthma phenotypes during the life course.

Sensitivity to food additives, vaso-active amines and salicylates: a review of the evidence

Although there is considerable literature pertaining to IgE and non IgE-mediated food allergy, there is a paucity of information on non-immune mediated reactions to foods, other than metabolic disorders such as lactose intolerance. Food additives and naturally occurring 'food chemicals' have long been reported as having the potential to provoke symptoms in those who are more sensitive to their effects. Diets low in 'food chemicals' gained prominence in the 1970s and 1980s, and their popularity remains, although the evidence of their efficacy is very limited. This review focuses on the available evidence for the role and likely adverse effects of both added and natural 'food chemicals' including benzoate, sulphite, monosodium glutamate, vaso-active or biogenic amines and salicylate. Studies assessing the efficacy of the restriction of these substances in the diet have mainly been undertaken in adults, but the paper will also touch on the use of such diets in children. The difficulty of reviewing the available evidence is that few of the studies have been controlled and, for many, considerable time has elapsed since their publication. Meanwhile dietary patterns and habits have changed hugely in the interim, so the conclusions may not be relevant for our current dietary norms. The conclusion of the review is that there may be some benefit in the removal of an additive or a group of foods high in natural food chemicals from the diet for a limited period for certain individuals, providing the diagnostic pathway is followed and the foods are reintroduced back into the diet to assess for the efficacy of removal. However diets involving the removal of multiple additives and food chemicals have the very great potential to lead to nutritional deficiency especially in the paediatric population. Any dietary intervention, whether for the purposes of diagnosis or management of food allergy or food intolerance, should be adapted to the individual's dietary habits and a suitably trained dietitian should ensure nutritional needs are met. Ultimately a healthy diet should be the aim for all patients presenting in the allergy clinic.