The diagnosis and management of food allergies. Position paper of the Food Allergy Section the Polish Society of Allergology

Unveiling the Immunomodulatory Potential of Phenolic Compounds in Food Allergies

Food allergies are becoming ever more prevalent around the world. This pathology is characterized by the breakdown of oral tolerance to ingested food allergens, resulting in allergic reactions in subsequent exposures. Due to the possible severity of the symptoms associated with this pathology, new approaches to prevent it and reduce associated symptoms are of utmost importance. In this framework, dietary phenolic compounds appear as a tool with a not fully explored potential. Some phenolic compounds have been pointed to with the ability to modulate food allergies and possibly reduce their symptoms. These compounds can modulate food allergies through many different mechanisms, such as altering the bioaccessibility and bioavailability of potentially immunogenic peptides, by modulating the human immune system and by modulating the composition of the human microbiome that resides in the oral cavity and the gastrointestinal tract. This review deepens the state-of-the-art of the modulation of these mechanisms by phenolic compounds. While this review shows clear evidence that dietary supplementation with foods rich in phenolic compounds might constitute a new approach to the management of food allergies, it also highlights the need for further research to delve into the mechanisms of action of these compounds and decipher systematic structure/activity relationships.

The use of inhibition assay in Api g 7 suspected allergy in a female patient with anaphylaxis: A case report

The symptoms of celery allergy are mainly presented as oral allergy symptom, but there are several case reports of patients who experienced anaphylaxis. Defensin (Api g 7), as a novel allergen in celery root, was described in 2022 r. The female patient had a history of several episodes of dyspnea and cough, associated with ingestion of spice mixes containing dried celery. Up to the point of hospitalization, there were no objective tests, either sIgE or skin prick tests, that would confirm celery sensitization. During hospitalization, patient had a positive double-blind placebo-controlled food challenge with cooked celery. The patient was sensitized to mugwort defensin Art v 1. An inhibition assay with celery allergen extract was performed to prove cross-sensitization between Art v 1 and celery allergen responsible for symptoms in the patient. In conclusion, Api g 7 is an important celery allergen that can be responsible for severe reactions. Its cross-reactivity with Art v 1 is characteristic. Negative diagnostic tests with celery do not exclude Api g 7 sensitization.

Methodological Principles of Nasal Food Challenge

Thanks to their valuable assessment possibilities (subjective complaints and changes in nasal patency during the examination), nasal provocation tests may serve as an alternative tool for oral food challenges in the future. However, this test requires successive attempts to regulate its methodology in order to develop a standardized lyophilisate form and determine the threshold dose for a positive result. The study objective was to present the methodological foundation for nasal food allergen provocation tests induced by freeze-dried powdered chicken egg whites. A control group of 25 individuals with no history of allergy to chicken eggs or any other allergy was included in the study. Optical rhinometry and visual analog scales were used to assess the response of nasal mucosa to local allergen challenges. Minor variations in nasal flows, as measured by optical rhinometry, were observed in the provocation tests. The mean optical density measurements (as measured regardless of the allergen dose used) varied from positive to negative values and vice versa, e.g., amounting to 0.018 OD (standard deviation 0.095) at 15 min and -0.011 OD (standard deviation 0.090) at 30 min. No significant differences were observed concerning the perceived nasal discomfort using the visual analog scale. Due to the absence of nasal mucosal reactivity, nasal challenge is an excellent methodological tool for implementing food allergen tests.

Food Allergies and Parasites in Children

The dynamically growing incidence of food allergies forces the scientific community to develop new methods for their diagnosis, differentiation, and effective treatment. Parasitoses appear much less frequently in the scientific literature, as well as among the presumed causes of numerous conditions. The similarity of inflammatory mechanisms in allergies and parasitosis necessitates a revision of current diagnostic standards. A lack of specificity and the coincidence of symptoms at an early stage of disease can lead to misdiagnosis. In this paper, we attempted to perform a comparative analysis of the similarities and differences in symptoms for these two types of diseases. We described the molecular mechanisms and metabolic pathways of food allergy and parasitosis. We presented the available research methods and directions of ongoing studies aimed at implementing precise medical techniques for differential diagnosis. We discussed the allergenic properties of certain parasite proteins, using the example of myofibrillar tropomyosins from the nematode Anisakis simplex. The literature in the fields of allergology and parasitology leads to the conclusion that it is reasonable to run parallel allergological and parasitological diagnostics in patients with non-specific symptoms. This approach will facilitate accurate and early diagnosis and implementation of effective therapy.

Management of Adult Patients with Gastrointestinal Symptoms from Food Hypersensitivity-Narrative Review

The incidence of food hypersensitivity has increased dramatically over the years not only among children but also in adults. Adult patients are usually less suspected of food hypersensitivity symptoms since food allergies are more typical for small children, with a tendency to outgrow the condition. The aim of this article is to increase awareness of hypersensitivity to food symptoms and their diagnosis and treatment possibilities among gastroenterologists and other health care professionals dealing with this type of patient. Symptoms of many gastrointestinal disorders, especially functional, may be driven by different types of mechanisms, and food intolerance or allergy should be considered as a potential cause. This article presents the current understanding of the epidemiology, diagnosis and treatment of immune- and non-immune-mediated food-induced diseases. Diagnosis of food hypersensitivity is based mainly on medical history, different types of sensitivity tests, e.g., hydrogen breath test, specific IgE (sIgE) serum concentration, tissue eosinophil count, skin tests and oral food challenges considered as a "gold standard" for food allergy. Elimination diet and pharmacologic treatment for allergy symptoms are first-line therapies. Eosinophilic gastrointestinal diseases are often caused by non-IgE-mediated food allergies, require endoscopic biopsy samples to confirm diagnosis and proper elimination diet often combined with steroids or proton pump inhibitor agents for treatment. Mast cell activation syndrome (MCAS) derives from pathologic reaction of mast cells with increased tryptase serum level as a marker. Symptoms may occur in the digestive, respiratory, skin, neurologic and cardiovascular system. Treatment is based on histamine type 1, type 2 (H1, H2) receptor antagonists and other mast cell stabilizing agents. Carbohydrate intolerances are the most common type of food hypersensitivity in adult patients, and an elimination diet is effective for reducing symptoms. Food additives hypersensitivity remains difficult to diagnose, but use of a diet low in chemical substances alleviates symptoms and helps to diagnose the triggering factors.

Nasal mucosal reactivity assessment via a double-blind placebo-controlled food challenge with cow's milk allergens

Background

Allergies, including food allergies, are a considerable clinical and public-health problem. The introduced preventive measures and differential diagnostics, including oral food challenges, are the gold standard for determining further treatment planning.

Case presentation

We present a case of an 18-year-old girl with a cow’s milk allergy who underwent an oral food challenge (double blind oral food challenge). Such a challenge may be confounded by inducing a response from other systems and organs, which provides theoretical grounds for the use of other methods of assessing the body’s response to food allergens (response demonstrated by the upper respiratory tract). Based on this idea, in order to assess the degree of mucosal response, we used optical rhinometry as an objective method for nasal patency evaluation, as well as identification of tryptase level in nasal lavage fluid and exfoliative cytology of nasal mucosa. The results of these tests confirmed positive reaction of the nasal mucosa in the course of the oral allergen challenge.

Conclusions

The observed increase in the nasal mucosal reactivity that accompanies oral food challenges may suggest a potential for using food allergens in nasal allergen provocation testing in order to diagnose food allergies.

Non-IgE Mediated Hypersensitivity to Food Products or Food Intolerance—Problems of Appropriate Diagnostics

The diagnosis of food intolerance is tricky due to the different etiologies of adverse reactions. There is also a lack of clear rules for interpreting alternative tests used to diagnose these problems. The analyses of IgG4 concentration in serum or cytotoxic tests became the basis of elimination diets. However, it can result in nutritional deficiencies and loss of tolerance to eliminated foods. Our study aimed to assess the necessity of food elimination in four cases with food intolerance symptoms based on alternative diagnostic tests. Four patients without food allergies, who manifested diverse clinical symptoms after food, were presented due to the following factors: clinical history, diagnostic tests, elimination diet, and filaggrin gene (FLG) mutation. It was found that higher IgG4 levels against foods and higher cytotoxic test values are not clinically relevant in each of the studied individuals. They should not be decisive for the elimination of food products. The study of FLG-SNVs revealed the association of some clinical symptoms in patients with hypersensitivity to several food allergens and reported genetic variants in the FLG gene.

Exercise induced anaphylaxis in kiwi allergic patient: case report

Background

An allergy to kiwi is rare in Poland. Most (65–72%) of the patients who are allergic to kiwi report symptoms of an oral allergy syndrome (OAS); however, systemic manifestations (18–28%) have also been reported.

Case report

A 27-year-old male patient, previously not suffering from chronic diseases, exercised in the gym. He began with isometric training and then continued with aerobic exercise on a treadmill. After exercise, he ate 2 kiwi (Actinidia deliciosa) fruits. He experienced a swelling of the lips after eating the fruit, followed by an itchy scalp and a swollen face. Approximately 60 min later, the symptoms worsened: the patient suffered from generalized hives, general weakness and a "rumbling" sensation in ears. The patient's condition improved upon the consumption of antihistamines. However, the swelling of the face persisted for 24 h despite previously eating a kiwi without any side effects. By means of diagnostics based on allergen components, an allergy to grass allergen components, especially timothy grass—Phl p 1, Phl p 2 and Phl p 5, was confirmed. The presence of IgE that is specific for Act d 2 kiwi was also found. The patient had an oral food challenge with kiwi fruit at rest and after exercise provocation test. The challenge was negative at rest and positive after exercise. A food-dependent exercise-induced anaphylaxis gathered with a kiwi sensitization was diagnosed.

Conclusion

To our knowledge, this case is the first report of a kiwi-allergic patient in whom exercise was a necessary cofactor to induce an anaphylactic reaction.

A positive feedback loop reinforces the allergic immune response in human peanut allergy

Food allergies are a leading cause of anaphylaxis, and cellular mechanisms involving antigen presentation likely play key roles in their pathogenesis. However, little is known about the response of specific antigen-presenting cell (APC) subsets to food allergens in the setting of food allergies. Here, we show that in peanut-allergic humans, peanut allergen drives the differentiation of CD209+ monocyte-derived dendritic cells (DCs) and CD23+ (FcєRII) myeloid dendritic cells through the action of allergen-specific CD4+ T cells. CD209+ DCs act reciprocally on the same peanut-specific CD4+ T cell population to reinforce Th2 cytokine expression in a positive feedback loop, which may explain the persistence of established food allergy. In support of this novel model, we show clinically that the initiation of oral immunotherapy (OIT) in peanut-allergic patients is associated with a decrease in CD209+ DCs, suggesting that breaking the cycle of positive feedback is associated with therapeutic effect.

OVA-Experienced CD4+ T Cell Transfer and Chicken Protein Challenge Affect the Immune Response to OVA in a Murine Model

Chicken meat is often a major component of a modern diet. Allergy to chicken meat is relatively rare and occurs independently or in subjects allergic to ovalbumin (OVA). We examined the effect of adoptive transfer of OVA-CD4⁺ T cells on the immune response to OVA in mice fed chicken meat. Donor mice were injected intraperitoneally with 100 µg of OVA with Freund’s adjuvant two times over a week, and CD4⁺ T cells were isolated from them and transferred to naïve mice (CD4⁺/OVA/ChM group), which were then provoked with OVA with FA and fed freeze-dried chicken meat for 14 days. The mice injected with OVA and fed chicken meat (OVA/ChM group), and sensitized (OVA group) and healthy (PBS group) mice served as controls. Humoral and cellular response to OVA was monitored over the study. The CD4⁺/OVA/ChM group had lowered levels of anti-OVA IgG and IgA, and total IgE. There were significant differences in CD4⁺, CD4⁺CD25⁺, and CD4⁺CD25⁺Foxp3⁺ T cells between groups. OVA stimulation decreased the splenocyte proliferation index and IFN-γ secretion in the CD4⁺/OVA/ChM group compared to the OVA group. IL-4 was increased in the OVA/ChM mice, which confirms allergenic potential of the egg–meat protein combination. Transfer of OVA-experienced CD4⁺ T cells ameliorated the negative immune response to OVA.

Clinical phenotypes of childhood food allergies based on immune mechanisms: A multicenter study

Background: Food allergies (FA) are an important public health concern that place a major burden on the lives of children and their families. The complex pathogenesis of FAs results in multisystemic and heterogenous clinical presentations. Objective: To evaluate, according to immune mechanisms, the characteristics and risk factors of childhood FA in Turkey. Methods: This descriptive multicenter study included 1248 children with FA, aged < 18 years,, who were evaluated by pediatric allergists in 26 different centers. Results: Immune mechanisms of FA were immunoglobulin E (IgE) mediated in 71.8%, non-IgE mediated in 15.5%, and mixed IgE/non-IgE mediated in 12.7% of the patients. An episode of anaphylaxis had occurred in 17.6% of IgE-mediated FA. The most common food allergens were classified into five categories (in order of decreasing frequency): cow's milk, egg, tree nuts and/or peanut, wheat, and seafood. Allergies to cow's milk and egg declined significantly with age, whereas tree nuts and/or peanut allergies increased with age. The 0-2 year age group accounted for 62.5% of the cases. The most frequent cause of FA and food anaphylaxis was cow's milk before age 13 years and tree nuts and/or peanut during adolescence (ages 13-18 years). Compared with other phenotypes, male sex (odds ratio [OR] 1.486; p = 0.032), sibling(s) (OR 1.581; p = 0.021), and maternal atopy (OR 1.531; p = 0.045) increased the likelihood of IgE-mediated FA, whereas high household income (OR 1.862; p = 0.026) increased the likelihood of non-IgE-mediated FA in multivariate regression analysis. Conclusion: This study showed that the clinical findings of FA were highly variable, depending on age and underlying immune mechanism. Knowing the population characteristics will enable better management of FA in children.

A Systematic Review of Food Allergy: Nanobiosensor and Food Allergen Detection

Several individuals will experience accidental exposure to an allergen. In this sense, the industry has invested in the processes of removing allergenic compounds in food. However, accidental exposure to allergenic proteins can result from allergenic substances not specified on labels. Analysis of allergenic foods is involved in methods based on immunological, genetic, and mass spectrometry. The traditional methods have some limitations, such as high cost. In recent years, biosensor and nanoparticles combined have emerged as sensitive, selective, low-cost, and time-consuming techniques that can replace classic techniques. Nevertheless, each nanomaterial has shown a different potential to specific allergens or classes. This review used Preferred Reporting Items for Systematic Reviews and the Meta-Analysis guidelines (PRISMA) to approach these issues. A total of 104 articles were retrieved from a standardized search on three databases (PubMed, Scopus and Web of Science). The systematic review article is organized by the category of allergen detection and nanoparticle detection. This review addresses the relevant biosensors and nanoparticles as gold, carbon, graphene, quantum dots to allergen protein detection. Among the selected articles it was possible to notice a greater potential application on the allergic proteins Ah, in peanuts and gold nanoparticle-base as a biosensor. We envision that in our review, the association between biosensor and nanoparticles has shown promise in the analysis of allergenic proteins present in different food samples.

Food Allergy Insights: A Changing Landscape

The panorama of food allergies (FA) has changed profoundly in recent years. In light of recent advances in knowledge of pathogenetic mechanisms and a greater attention to the multifaceted range of possible clinical manifestations, there is a need for a critical review of past classifications. Changes in nutrition, environment and lifestyles around the world are modifying the global FA epidemiology and new FA phenotypes are also emerging. Furthermore, both biotechnological advances in this field and recent personalized therapies have improved the diagnostic and therapeutic approach to FA. Consequently, both the prevention and clinical management of FA are rapidly changing and new therapeutic strategies are emerging, even revolutionizing the current medical practice. Given the significant increase in the prevalence of FA in recent years, the objective of this review is to provide an updated and complete overview of current knowledge in its etiopathogenesis, diagnostics and therapy, useful not only for a better understanding of this frequent and complex pathology but also for practical guidance in its clinical management.

Use of IHF-QD Microscopic Analysis for the Detection of Food Allergenic Components: Peanuts and Wheat Protein

The aim of the study was to analytically evaluate quantum dots in immunohistofluorescence (IHF-QD) microscopic imaging as detectors of food allergens—peanut and wheat. The experiment was designed as two in silico experiments or simulations: (a) models of pastry samples were prepared with the addition of allergenic components (peanut and wheat protein components) and without the addition of allergenic components, and (b) positive and negative commercial samples underwent food allergen detection. The samples from both simulations were tested by the ELISA and IHF-QD microscopic methods. The primary antibodies (secondary antibodies to a rabbit Fc fragment with labeled CdSe/ZnS QD) were labelled at 525, 585, and 655 nm emissions. The use of quantum dots (QDs) has expanded to many science areas and they are also finding use in food allergen detection, as shown in the study. The study indicated that differences between the ELISA and IHF-QD microscopic methods were not observable among experimentally produced pastry samples with and without allergenic components, although differences were observed among commercial samples. The important value of the study is certainly the differences found in the application of different QD conjugates (525, 585, and 655). The highest contrast was found in the application of 585 QD conjugates that can serve for the possible quantification of present food allergens—peanuts and wheat. The study clearly emphasized that QD can be used for the qualitative detection of food allergens and can represent a reliable analytical method for food allergen detection in different food matrixes.

New Perspectives in Food Allergy

The improvement of the knowledge of the pathophysiological mechanisms underlying the tolerance and sensitization to food antigens has recently led to a radical change in the clinical approach to food allergies. Epidemiological studies show a global increase in the prevalence of food allergy all over the world and manifestations of food allergy appear increasingly frequent also in elderly subjects. Environmental and nutritional changes have partly changed the epidemiology of allergic reactions to foods and new food allergic syndromes have emerged in recent years. The deepening of the study of the intestinal microbiota has highlighted important mechanisms of immunological adaptation of the mucosal immune system to food antigens, leading to a revolution in the concept of immunological tolerance. As a consequence, new prevention models and innovative therapeutic strategies aimed at a personalized approach to the patient affected by food allergy are emerging. This review focuses on these new perspectives and their practical implications in the management of food allergy, providing an updated view of this complex pathology.

Association of the STAT6 rs3024974 (C/T) Polymorphism with IgE-Mediated Food Sensitization among West Bengal Population in India

INTRODUCTION

Genetic polymorphisms associated with IgE-mediated food sensitization have been a robust area of research for decades. A genome-wide search for susceptible loci regulating the IgE response (atopy) identified the candidate gene STAT6, which is important in the context of food allergic manifestations.

OBJECTIVE

The present study was designed to investigate the sensitization of West Bengal population against some common allergenic food items and to study the role of the STAT6 gene polymorphism in elevating food-specific IgE levels among sensitized individuals.

METHODS

Skin prick test was performed for 6 food items among 501 patients (126 children, 85 adolescents, and 290 adults)from West Bengal, India. Among them, 165 patients were selected for measurement of total IgE and food-specific IgE levels along with 165 controls. Finally, the STAT6 (rs3024974 (C/T) polymorphism was genotyped in 139 cases and control subjects.

RESULTS

Shrimp was identified as a dominant food allergen in adolescents and adults, whereas milk sensitization was highest in children. Food-sensitized patients with onset during childhood had significantly higher total IgE levels compared to patients with onset during adulthood (p < 0.00001). The frequency of the rs3024974 CC genotype in both cases and control subjects (55.40 and 46.76%, respectively) was higher than that of CT or TT. Patients with childhood onset bearing the CC genotype had significantly higher specific IgE levels in comparison to those with adult onset (p = 0.001).

CONCLUSION

Food sensitization has a genetic background and the rs3024974 polymorphism is associated with susceptibility and reaction severity in food-sensitized patients in West Bengal population in India.

The impact of immunomodulatory factors from maternal diet during pregnancy on cow's milk allergy in offspring - A pilot study in the paediatric population of the Kuyavian-Pomeranian Voivodship

BACKGROUND

The key role of dietary factors in immunotolerance promotion and allergic diseases prevention has been emphasised. The aim of the study was the analysis of the impact of immunomodulatory dietary components, consumed by pregnant women, on the development of cow's milk allergy (CMA) in their offspring.

MATERIALS AND METHODS

Fifty-one pairs of mothers and their CMA-offspring were included in the study group. The analysis of a daily intake of selected dietary components was conducted retrospectively with the application of a seven-day diet of a mother in the third trimester of gestation and the authors' own questionnaire. The Diet 5.D programme was used.

RESULTS

An average daily retinol intake by study-group mothers was significantly lower than by control-group mothers and valued 375.6μg/d vs. 543.7μg/d (p=0.040), respectively. Folates intake in the study group was 598.8μg/d vs. 361.1μg/d in the control group (p=0.001). Vitamin D in the study group was statistically lower - 3.6μg/d, comparing to the control group - 6.9μg/d (p=0.038). Average LC-PUFA intake by mothers with allergic children was 0.09g/d, while in the control group 0.18g/d (p=0.016). An analysis of the diet revealed that significantly more mothers of children from the control group (n=12; 48%) consumed fish 2-3 times per month in comparison to the study group (n=9; 17.6%) (p=0.007).

CONCLUSIONS

Vitamin D, A, LC-PUFA, retinol, riboflavin and fish consumption by pregnant mothers of CMA-children was significantly lower, whereas beta-carotene and folates consumption was significantly higher than that of mothers with non-allergic children.

Food-dependent, exercise-induced anaphylaxis in a patient allergic to peach

Determining the single factor that triggered anaphylactic shock can be challenging. We present an interesting case of a 25-year-old female patient with recurrent anaphylactic reactions developing after eating various foods, particularly in presence of co-factors of allergic reactions. Symptoms occurred after consumption of various kinds of foods - peach, pancakes with cottage cheese and fruit, a meal from a Chinese restaurant - all eaten on other occasions without symptoms. During diagnosis, skin prick tests were negative for all tested allergen extracts (both inhalatory and food) from Allergopharma. Prick by prick tests were positive for the peach - wheal diameter - 6 mm, nectarine - 4 mm (histamine 4 mm, negative control 0 mm). Increased levels of asIgE were found for allergens of peach (0.55 kU/L).Open challenge test with one mid-size peach combined with the physical exercise challenge test was positive. ImmunoCAP ISAC test indicated increased levels of IgE specific for the lipid transfer protein (LTP) for walnut (nJug r 3), peach (Pru p 3), wheat (rTri a 14) and plane tree (rPla a 3). The patient was diagnosed with food-dependent, exercise-induced anaphylaxis associated with an allergy to lipid transport proteins (LTPs).