Natural history of perceived food hypersensitivity and IgE sensitisation to food allergens in a cohort of adults

Prevalence estimates of eight big food allergies in Europe: Updated systematic review and meta-analysis

In 2014, the European Academy of Allergy and Clinical Immunology published prevalence estimates for food allergy (FA) and food sensitization (FS) to the so-called eight big food allergens (i.e. cow's milk, egg, wheat, soy, peanut, tree nuts, fish and shellfish) in Europe for studies published between 2000 and 2012. The current work provides 10-year updated prevalence estimates for these food allergens. A protocol was registered on PROSPERO before starting the research (reference number CRD42021266657). Six databases were searched for studies published 2012-2021, added to studies published up to 2012, resulting in a total of 93 studies. Most studies were graded as at moderate risk of bias. The overall pooled estimates for all age groups of self-reported lifetime prevalence were as follows: cow's milk (5.7%, 95% confidence interval 4.4-6.9), egg (2.4%, 1.8-3.0), wheat (1.6%, 0.9-2.3), soy (0.5%, 0.3-0.7), peanut (1.5%, 1.0-2.1), tree nuts (0.9%, 0.6-1.2), fish (1.4%, 0.8-2.0) and shellfish (0.4%, 0.3-0.6). The point prevalence of food challenge-verified allergy were as follows: cow's milk (0.3%, 0.1-0.5), egg (0.8%, 0.5-1.2), wheat (0.1%, 0.01-0.2), soy (0.3%, 0.1-0.4), peanut (0.1%, 0.0-0.2), tree nuts (0.04%, 0.02-0.1), fish (0.02%, 0.0-0.1) and shellfish (0.1%, 0.0-0.2). With some exceptions, the prevalence of allergy to common foods did not substantially change during the last decade; variations by European regions were observed.

Soy Gly m 8 sIgE Has Limited Value in the Diagnosis of Soy Allergy in Peanut Ara h 2-Sensitized Adults

INTRODUCTION

Recently, specific IgE (sIgE) sensitization against Gly m 8 (soy 2S albumin) has been described as a good diagnostic marker for soy allergy (SA). The aim of this study was to evaluate the diagnostic value of Gly m 8 by determining the sensitization profiles based on the homologues soy allergens Bet v 1, Ara h 1, Ara h 2, and Ara h 3.

METHODS

Thirty soy-allergic adults were included; sIgE to total soy extract, Gly m 8, Gly m 4, Gly m 5, Gly m 6, Bet v 1, Ara h 1, Ara h 2, and Ara h 3 were determined. Sensitization patterns were analyzed and determined. The clinical relevance of sIgE of Gly m 8 sensitization was measured by assessing its capacity to degranulate basophils in Gly m8-sensitized patients by an indirect basophil activation test (iBAT).

RESULTS

Based on the sIgE patterns of sensitization, two groups of SA patients were identified: (i) peanut-associated SA group (all patients were sensitized to one or more of the peanut compounds) and (ii) non-peanut/PR-10-associated SA group (22 patients were sensitized to Gly m 4 and Bet v 1 but not to any of the peanut compounds). A high and significant correlation between total soy extract and Gly m 6 (R2 = 0.97), Gly m 5 (R2 = 0.85), and Gly m 8 (R2 = 0.78) was observed. A nonsignificant correlation was observed between the levels of sIgE of Gly m 8 versus Ara h2. The iBAT results showed that Gly m 8 did not induce basophil degranulation in any of the peanut-associated patients, indicating that the Gly m8 sensitizations were not clinically relevant.

CONCLUSIONS

Gly m 8 was not a major allergen in the selected soy-allergic population. The iBAT results indicated that Gly m 8 was not able to induce basophil degranulation in sIgE Gly m 8-sensitized soy-allergic patients. Thus, Gly m 8 would have no added value in the diagnosis of SA in the present study population.

Food hypersensitivity: an examination of factors influencing symptoms and temporal changes in the prevalence of sensitization in an adult sample

BACKGROUND/OBJECTIVES

Food hypersensitivity (FHS) is common, but little is known about the factors associated with severe reactions, age of onset and whether sensitization persists. This study examines the factors associated with self-reported severe food reactions, onset age and the changes in prevalence of sensitization to foods over time in an adult sample.

SUBJECTS/METHODS

We used data from adults taking part in the European Community Respiratory Health Survey (ECRHS) III (2010-2014) who provided information on food hypersensitivity, including symptoms, suspected culprit food and onset age (n = 4865). A subsample from six countries had serum food-specific IgE tested for 25 core foods and also in 10 years earlier (ECRHS II). We applied logistic regression and McNemar's test for analyses.

RESULTS

The prevalence of self-reported FHS was 13.5% at ECRHS III. Of those providing information on symptoms (n = 611), 26.4% reported severe reactions. About 80% of 1033 reported food-specific reactions (reported by 596 participants) began after age 15. History of asthma (odds ratio OR 2.12 95% confidence interval CI 1.13-3.44) and a younger age of onset of FHS (OR 1.02, 95% CI 1.01-1.03, per year) were associated with higher risks of a lifetime experience of severe food reactions. In the subsample with IgE tested in both surveys (n = 1612), the overall prevalence of sensitization to foods did not change over 10 years.

CONCLUSION

Our findings support previous observations of more severe food reactions in people with asthma and that most FHS reported by this sample started after age 15. We found no evidence of changes in the prevalence of sensitization to food in adults followed for 10 years.

Frequency of food allergy in Europe: An updated systematic review and meta-analysis

Food allergy (FA) is increasingly reported in Europe, however, the latest prevalence estimates were based on studies published a decade ago. The present work provides the most updated estimates of the prevalence and trends of FA in Europe. Databases were searched for studies published between 2012 and 2021, added to studies published up to 2012. In total, 110 studies were included in this update. Most studies were graded as moderate risk of bias. Pooled lifetime and point prevalence of self-reported FA were 19.9% (95% CI 16.6-23.3) and 13.1% (95% CI 11.3-14.8), respectively. The point prevalence of sensitization based on specific IgE (slgE) was 16.6% (95% CI 12.3-20.8), skin prick test (SPT) 5.7% (95% CI 3.9-7.4), and positive food challenge 0.8% (95% CI 0.5-0.9). While lifetime prevalence of self-reported FA and food challenge positivity only slightly changed, the point prevalence of self-reported FA, sIgE and SPT positivity increased from previous estimates. This may reflect a real increase, increased awareness, increased number of foods assessed, or increased number of studies from countries with less data in the first review. Future studies require rigorous designs and implementation of standardized methodology in diagnosing FA, including use of double-blinded placebo-controlled food challenge to minimize potential biases.

Ultra-processed foods and allergic symptoms among children and adults in the United States: A population-based analysis of NHANES 2005-2006

Design

There is a strong correlation between dietary intake and allergic diseases. Ultra-processed foods (UPFs) are gradually becoming dominant worldwide and causing health problems for children and adults. We hope to determine whether links exist between UPFs and allergic symptoms.

Methods

We investigated data from 2,736 children (16-19 years) and 4,256 adults (≥20 years) from the National Health and Nutritional Examination Survey (NHANES) 2005-2006. The associations between the mean UPFs contribution to total energy intake and all allergic symptoms (IgE, current asthma, allergy, rash, sneeze, wheeze, eczema, and hay fever) were estimated by weighted multivariate logistic regression.

Results

Logistic regression analysis showed UFPs were negatively associated with IgE levels in children. Those with higher quartiles had a reduced risk from 16% (OR, 0.84, 95%CI, 0.55 to 1.28) to 34% (OR, 0.66, 95%CI, 0.49 to 0.89), p for trend = 0.006. UPFs were also positively related to current asthma in children with an increased risk of 11% (OR, 1.11, 95%CI, 0.79 to 1.56) to 76% (OR, 1.76, 95%CI, 1.10 to 2.82), p for trend = 0.0393. UPFs were also associated with eczema in girls. But there was no association observed between UPFs and allergic symptoms in adults.

Conclusion

Our results suggested that UPFs assessed by the NOVA system were associated with IgE, current asthma in children, and eczema in girls. These results further support the need to test the association of modern dietary patterns with allergic symptoms.

Phenotypic characterization of childhood- and adult-onset food allergy among adults in the United States

Background

Food allergy (FA) affects ~10% of adults; however, little is known about the extent to which FA phenotypes and psychosocial burden vary depending on timing of allergy onset, whether in childhood or as an adult.

Objective

This study explored FA characteristics according to timing of FA onset in US adults.

Methods

Between 2015 and 2016, a cross-sectional survey was administered to 40,443 US adults. Complex survey-weighted results were tabulated across key demographic and clinical strata. Linear regression models explored covariate-adjusted variability in FA-related psychosocial burden across 3 groups: (1) adults solely with childhood-onset FA, (2) adults solely with adult-onset FA, and (3) adults with both childhood- and adult-onset FA.

Results

Adults with both childhood- and adult-onset FAs, compared to adults with solely childhood- or adult-onset FAs, are significantly more likely to have severe FAs (57.3%, 52.6%, 43.2%), physician-diagnosed FAs (54.2%, 52.4%, 33.0%), and multiple FAs (74.8%, 41.0%, 30.3%) (P < .001). Adults solely with childhood-onset FA, compared to adults solely with adult-onset FA, had significantly lower rates of environmental allergies (27.6% vs 39.2%; P < .001) and medication allergies (17.3% vs 25.9%; P < .001). Adults with both childhood- and adult-onset FAs reported highest rates of all comorbidities. Adults solely with adult-onset FA reported significantly lower FA-related psychosocial burden (P < .05).

Conclusion

Differences exist in reaction severity, health care utilization, atopic comorbidities, and psychosocial burden according to the timing of FA onset. Future research exploring the heterogeneity of phenotypic expressions of adult FA may inform underlying mechanisms.

Food allergy and hypersensitivity reactions in children and adults-A review

Adverse reactions after food intake are commonly reported and a cause of concern and anxiety that can lead to a very strict diet. The severity of the reaction can vary depending on the type of food and mechanism, and it is not always easy to disentangle different hypersensitivity diagnoses, which sometimes can exist simultaneously. After a carefully taken medical history, hypersensitivity to food can often be ruled out or suspected. The most common type of allergic reaction is immunoglobulin E (IgE)-mediated food allergy (prevalence 5-10%). Symptoms vary from mild itching, stomach pain, and rash to severe anaphylaxis. The definition of IgE-mediated food allergy is allergic symptoms combined with specific IgE-antibodies, and therefore only IgE-antibodies to suspected allergens should be analyzed. Nowadays, methods of molecular allergology can help with the diagnostic process. The most common allergens are milk and egg in infants, peanut and tree nuts in children, and fish and shellfish in adults. In young children, milk/egg allergy has a good chance to remit, making it important to follow up and reintroduce the food when possible. Other diseases triggered by food are non-IgE-mediated food allergy, for example, eosinophilic esophagitis, celiac disease, food protein-induced enterocolitis syndrome, and hypersensitivity to milk and biogenic amines. Some of the food hypersensitivities dominate in childhood, others are more common in adults. Interesting studies are ongoing regarding the possibilities of treating food hypersensitivity, such as through oral immunotherapy. The purpose of this review was to provide an overview of the most common types of food hypersensitivity reactions.

Relationship between longitudinal changes in type-2 inflammation, immunoglobulin E sensitization, and clinical outcomes in young asthmatics

BACKGROUND

Asthma is a heterogeneous condition where biomarkers may be of considerable advantage in diagnosis and therapy monitoring. However, the changes in asthma biomarkers and immunoglobulin E (IgE) over the course of life has not been extensively investigated.

OBJECTIVE

To study longitudinal changes in type-2 inflammatory biomarkers, IgE, and clinical outcomes, and the association between these changes, in young asthmatics.

METHODS

Asthmatics (age 10-35 years, n = 253) were examined at baseline and at a follow-up visit, 43 [23-65] (median [range]) months later. Subjects were analyzed using the multi-allergen tests Phadiatop and fx5 (ImmunoCAP) and grouped based on the baseline allergen-specific IgE antibody (sIgE) concentration: <0.10, 0.10-0.34, and ≥0.35 kU_A /L. The relationship between changes (Δ values) in type-2 biomarkers (individualized fraction of exhaled nitric oxide [FeNO%], blood eosinophil [B-Eos] count, total IgE [tIgE] and sIgE, lung function [% predicted forced expiratory volume in 1 second (FEV₁ ) and FEV₁ /forced vital capacity (FVC)], and Asthma Control Test [ACT]) score were determined.

RESULTS

At follow up, FEV₁ and FEV₁ /FVC had decreased (93.6% vs. 95.8%, and 93.4% vs. 94.7% of predicted, respectively [p < 0.001 both]), whereas ACT score had increased (21.6 vs. 20.6, p = 0.001). A significant decline in lung function was seen in subjects with sIgE ≥ 0.10 kUA/L, but not in those with undetectable sIgE (<0.10 kU_A /L). Furthermore, tIgE and sIgE declined over time (p < 0.001 all) whereas FeNO% and B-Eos count were not significantly changed. In univariate analysis, significant negative correlations between ∆B-Eos count and ∆FeNO%, on one hand, and changes in lung function, on the other hand, were seen, and multivariate analysis showed an independent relationship between ΔFeNO%, and ΔFEV₁ (p < 0.05) and ΔFEV₁ /FVC% (p < 0.01). Sex-specific analysis showed that the independent association between ΔFeNO%, and ΔFEV₁ remained only in females (p = 0.005), and there was a significant interaction with sex (p = 0.02).

CONCLUSION

In young asthmatics, IgE levels declined over 43 months, whereas FeNO and B-Eos remained unchanged. In spite of improved asthma control, an accelerated lung function decline was seen in patients with detectable sIgE at baseline, and the decline correlated with changes in type-2 biomarkers. Particularly, the increase in individualized FeNO associated independently with decline in FEV₁ in females.

A systematic review of psychological, clinical and psychosocial correlates of perceived food intolerance

OBJECTIVE

Perceived food intolerance (PFI) is a distressing condition reported by 3% - 35% of individuals, whereas prevalence of food allergy is 0.9%-3%. The present paper aims to systematically review the evidence for psychological, clinical and psychosocial factors associated with PFI in order to advance the current understanding.

METHODS

Articles published from 1970 until October 2020 were identified. Case-control, prospective cohort, cross-sectional and retrospective studies published in English that a) included a subject population of adults over 18 with PFI and b) examined psychological, clinical and/or psychosocial factors of PFI were reviewed against inclusion criteria. Methodological quality was assessed, data extracted, and a narrative synthesis conducted.

RESULTS

Of 2864 abstracts identified, thirty-six articles met inclusion criteria. Evidence consistently found PFI is associated with female sex, and individuals with PFI often report physical health complaints including gastrointestinal and extraintestinal symptoms, and gastrointestinal and atopic conditions. Evidence for an association between psychological factors and PFI was inconsistent, although some suggested increased levels of common mental disorders and distress. Findings regarding psychosocial factors were mixed and sociodemographic data were infrequently collected.

CONCLUSIONS

PFI is associated with female sex and gastrointestinal and extraintestinal complaints. Limited high-quality evidence supports the role of psychological factors associated with PFI. High-quality research using prospective and longitudinal designs with multivariate analyses is needed. Future research should explore modifiable psychological factors as potential targets for intervention and identify clinical and psychosocial risk factors of PFI to aid in formulating a biopsychosocial model of PFI.

Low Frequency of IgE-Mediated Food Hypersensitivity in Mastocytosis

BACKGROUND

Patients with mastocytosis have an increased risk for severe anaphylaxis, particularly to Hymenoptera venoms. These patients may also develop more often systemic hypersensitivity reactions to certain foods. However, this issue has not been systematically investigated.

OBJECTIVE

To determine prevalence and severity of food hypersensitivity (FH) reactions among patients with clonal mast cell disorders (CMDs).

METHODS

A retrospective study was conducted among 204 (age ≥18 years) consecutive patients who presented with confirmed CMD (170 with mastocytosis and 34 with monoclonal mast cell activation syndrome). All patients underwent thorough allergy workup where self-reported FH reactions were evaluated.

RESULTS

The prevalence of self-reported FH was 20.6%. The frequency of immunologically mediated reactions was uncommon, because only 3.4% were confirmed by relevant history and IgE sensitization. Among patients with FH, 5 had severe anaphylaxis corresponding to an overall prevalence of 2.5%. Most symptoms were restricted to skin (86%), followed by gastrointestinal tract symptoms (45%)-similar to symptoms that occur in patients with mastocytosis also without food intake. Nuts, spicy foods, seafood, and alcohol were the most common incriminated elicitors. There was no significant difference between the groups regarding age, sex, atopic status, or IgE levels.

CONCLUSIONS

Anaphylaxis from foods in mastocytosis does exist and is severe, although foods are less frequent elicitors than insect venoms. Furthermore, the frequency of overall FH reactions is comparable with that in the general population and most reactions are mild, nonallergic, and unconfirmed. Consequently, our results do not support the elimination of any diet in patients with CMD without a history of FH.

Prevalence of food hypersensitivity in relation to IgE sensitisation to common food allergens among the general adult population in West Sweden

Background

The prevalence of self-experienced adverse reactions to foods seems to have an increasing trend in both adults and children. However, it is unclear if the prevalence of food hypersensitivity in the Swedish adult population is still rising, what symptoms are caused by different foods and which are the most common foods to which adults are more frequently IgE-sensitised.

Methods

In a cross-sectional study based on questionnaire responses, interviews and clinical examinations as part of the West Sweden Asthma Study, 1042 subjects from the general population, 17–78 years of age, living in Västra Götaland, Sweden, were included. The subjects reported symptoms for 56 specified foods and blood samples were taken to examine the IgE-sensitisation pattern for 9 common foods.

Results

Approximately 32% of adults reported food hypersensitivity, affecting mostly women and subjects less than 61 years old. The foods most often reported to cause adverse reactions were hazelnut (8.9%), apple (8.4%), milk (7.4%) and kiwi (7.3%). Less than one percent (0.9%) reported symptoms from ingestion of meat. Symptoms mostly affected the gastrointestinal tract (15%) and the skin (2.7%). Sixteen per cent were IgE-sensitised to common foods, most often to hazelnut (13.3%), peanut (4.9%) and almond (3.0%), while 5.9% reported symptoms and were IgE-sensitised to the same food, mainly to hazelnut (5.3%).

Conclusions

The prevalence of self-reported food hypersensitivity in West Sweden indicates a rising trend. The correspondence between self-reported symptoms and IgE-sensitisation to foods is generally poor, except for hazelnut and almond which exhibit moderate or fair correlation.

Grass-Allergic Children Frequently Show Asymptomatic Low-Level IgE Co-Sensitization and Cross-Reactivity to Wheat

BACKGROUND

Specific immunoglobulin E (IgE) sensitization to wheat is more common than a doctor's confirmed wheat allergy and is also frequently observed in grass pollen-allergic patients (pollinosis patients). Thus, the objective of this study was to investigate the level and feature of serological IgE cross-reactivity between grass pollen and wheat in a cohort of pollinosis subjects with no diagnosis of wheat allergy.

METHODS

Seventy-two children, aged 5-17 years, with a doctor's diagnosis of pollinosis, IgE towards grass pollen, and currently eating wheat were recruited. Serum samples were analyzed for IgE against wheat, timothy grass/wheat-specific allergen components, Pru p 3, and cross-reactive carbohydrate determinants (CCD) and specific IgE-binding inhibition experiments were performed.

RESULTS

Sixty percent of the grass pollen subjects were sensitized to wheat with a median of 0.5 kUA/L. Wheat-sensitized subjects were more often sensitized to the two allergens, Phl p 12 and CCD, known to be cross-reactive between grass and wheat. Sensitizations to seven wheat-specific allergens derived from the gluten fraction were, with the exception of one individual, only found in wheat-sensitized subjects. These subjects also more often reported current and past history of allergy to staple foods (milk, egg, wheat, soy, and fish).

CONCLUSION

Wheat sensitization caused by cross-reactivity but also by sensitization to wheat-specific allergens was common in the grass-allergic children and also associated with allergy to staple foods other than wheat. The results indicate the presence of a subgroup of pollinosis patients with simultaneous sensitization to wheat and food allergy not only caused by cross-reactions.

Immunological Processes Driving IgE Sensitisation and Disease Development in Males and Females

IgE sensitisation has increased significantly over the last decades and is a crucial factor in the development of allergic diseases. IgE antibodies are produced by B cells through the process of antigen presentation by dendritic cells, subsequent differentiation of CD4⁺ Th2 cells, and class switching in B cells. However, many of the factors regulating these processes remain unclear. These processes affect males and females differently, resulting in a significantly higher prevalence of IgE sensitisation in males compared to females from an early age. Before the onset of puberty, this increased prevalence of IgE sensitisation is also associated with a higher prevalence of clinical symptoms in males; however, after puberty, females experience a surge in the incidence of allergic symptoms. This is particularly apparent in allergic asthma, but also in other allergic diseases such as food and contact allergies. This has been partly attributed to the pro- versus anti-allergic effects of female versus male sex hormones; however, it remains unclear how the expression of sex hormones translates IgE sensitisation into clinical symptoms. In this review, we describe the recent epidemiological findings on IgE sensitisation in male and females and discuss recent mechanistic studies casting further light on how the expression of sex hormones may influence the innate and adaptive immune system at mucosal surfaces and how sex hormones may be involved in translating IgE sensitisation into clinical manifestations.

Association of Japanese cedar pollinosis and sensitization with HLA-DPB1 in the Japanese adolescent

BACKGROUND

Allergic rhinitis (AR) is a heterogeneous disorder that significantly affects daily activity, work productivity, sleep, learning, and quality of life in all generations. Japanese cedar (JC) pollen is the most common allergen responsible for the development of AR in Japan. AR caused by JC pollen is considered to be a multifactorial inheritance disease that is caused by both environmental and genetic factors. The aim of this study was to investigate whether Human Leukocyte Antigen-DPB1 (HLA-DPB1) is associated with JC sensitization/pollinosis.

METHODS

Subjects in the present study were 544 students at the University of Tsukuba from 2013 to 2015. PCR-SSOP was performed to determine each individual's HLA-DPB1 alleles. Logistic regression analysis was performed to examine relationships between JC-related phenotypes and alleles/amino acid polymorphisms of HLA-DPB1.

RESULTS

HLA-DPB1*02 allele were significantly associated with both JC sensitization/pollinosis (q < 0.05). Furthermore, HLA-DPB1*02:01 and HLA-DPB1*02:02 had a protective tendency for JC sensitization/pollinosis, and HLA-DPB1*05:01 had a susceptible tendency for sensitization (P < 0.05). In amino acid polymorphism analyses, Glutamic acid in position 69, Glycine-Glycine-Proline-Methionine in positions 84-87, Threonine in position 170 and Methionine in position 205 were also observed to have a protective tendency for JC sensitization (P < 0.05). Amino acid positions 69 and 84-87 were located in binding pocket 5 and 1 of HLA-DPβ1, respectively.

CONCLUSIONS

Amino acid changes in the allergen-binding pocket of HLA-DPβ1 are likely to influence pollinosis/sensitization to the allergenic peptide of JC pollen and determine the pollinosis risk for each individual exposed to JC pollen.

Changes over Time in IgE Sensitization to Allergens of the Fish Parasite Anisakis spp

BACKGROUND

Sensitization to Anisakis spp. can produce allergic reactions after eating raw or undercooked parasitized fish. Specific IgE is detected long after the onset of symptoms, but the changes in specific IgE levels over a long follow-up period are unknown; furthermore, the influence of Anisakis spp. allergen exposure through consumption of fishery products is also unknown.

OBJECTIVE

To analyse the changes in IgE sensitization to Anisakis spp. allergens over several years of follow-up and the influence of the consumption of fishery products in IgE sensitization.

METHODS

Total IgE, Anisakis spp.-specific IgE, anti-Ani s 1 and anti-Ani s 4 IgE were repeatedly measured over a median follow-up duration of 49 months in 17 sensitized patients.

RESULTS

Anisakis spp.-specific IgE was detected in 16/17 patients throughout the follow-up period. The comparison between baseline and last visit measurements showed significant decreases in both total IgE and specific IgE. The specific IgE values had an exponential or polynomial decay trend in 13/17 patients. In 4/17 patients, an increase in specific IgE level with the introduction of fish to the diet was observed. Three patients reported symptoms after eating aquaculture or previously frozen fish, and in two of those patients, symptom presentation was coincident with an increase in specific IgE level.

CONCLUSIONS

IgE sensitization to Anisakis spp. allergens lasts for many years since specific IgE was detectable in some patients after more than 8 years from the allergic episode. Specific IgE monitoring showed that specific IgE titres increase in some allergic patients and that allergen contamination of fishery products can account for the observed increase in Anisakis spp.-specific IgE level.

CLINICAL RELEVANCE

Following sensitization to Anisakis spp. allergens, the absence of additional exposure to those allergens does not result in the loss of IgE sensitization. Exposure to Anisakis spp. allergens in fishery products can increase the specific IgE level in some sensitized patients.

Self-reported prevalence and risk factors associated with food hypersensitivity in Mexican young adults

BACKGROUND

Food hypersensitivity (FH) is defined as any unfavorable reaction after the ingestion, contact, or inhalation of a food. Few FH prevalence studies have been performed in the Mexican adult population.

OBJECTIVE

To determine the prevalence of self-reported FH and probable food allergy (FA) among a sample of Mexican young adults and to determine the most commonly involved foods, associated symptoms, and risk factors.

METHODS

We designed an observational, cross-sectional study in which 1,253 young adults (aged 18-25 years) born in the State of Mexico answered a questionnaire concerning FH. We obtained information on personal and familial histories of allergic diseases, the involved foods, and the subsequent adverse reactions to their consumption.

RESULTS

The prevalence of FH was 30.1% and was significantly higher in women than in men (P < .001). The prevalence of probable FA was 5.9% and was also higher in women (P = .02). Gastrointestinal symptoms were reported in 83.1% of FH cases, whereas cutaneous symptoms and oral allergy syndrome were reported in FA cases. The food groups most associated with FH were dairy products (13.2%), vegetables (10.0%), and fruits (8.0%). The food groups most associated with FA were fruits (3.0%) and seafood (1.8%). Female sex, personal history of allergic diseases, maternal history of atopic dermatitis, and parental history of urticaria were significantly associated (P < .05) with the presence of FH.

CONCLUSION

FH in young adults might be more common than previously thought, especially in women. However, further studies are needed to confirm this situation in the Mexican population.

Parallel reductions of IgE and exhaled nitric oxide after optimized anti-inflammatory asthma treatment

Immunoglobulin E (IgE) is crucial for the development of airway inflammation in atopic asthma, and inhibition of IgE using monoclonal antibodies is now part of asthma therapy. However, the impact of ordinary anti-inflammatory treatment on IgE is unclear. The aim of this study was to investigate if optimization of treatment with inhaled corticosteroid (ICS) and leukotriene-receptor antagonist (LTRA) according to symptoms or exhaled nitric oxide (F_ENO) levels over a one-year period affects IgE concentrations. Altogether, 158 relatively well-controlled but multi-sensitized asthmatics (age 18-65 years), with ongoing ICS treatment at baseline, were included in this post hoc analysis of data from a randomized, controlled trial on F_ENO-guided asthma therapy. Asthma control and quality of life (Juniper ACQ and mAQLQ), F_ENO, and serum IgE were measured at baseline and after one year. Concentrations of IgE antibodies to six common perennial aeroallergens were summed up (perennial IgE). We found that perennial and total IgE decreased by 10.2% and 16.0% (P < .001 both comparisons). This was not related to allergen exposure, whereas the total use of ICS and LTRA during the year correlated with the reduction in perennial IgE (P = .030 and P = .013). The decrease in perennial and total IgE correlated significantly with the reduction in F_ENO (P < .003 and P < .001), and with improvements in ACQ and mAQLQ scores (P < 0.05, all comparisons). We conclude that one year of optimization of treatment with ICS and LTRA in patients with persistent atopic asthma resulted in significant decreases in total IgE and IgE antibodies; these decreases correlated with a reduction in F_ENO and improvements in asthma control and quality of life. Thus, IgE is reduced by ordinary asthma controller medications and the effect on IgE seems to be clinically important.

Self-reported adverse reactions and IgE sensitization to common foods in adults with asthma

Background

There is very few data available on the prevalence of food hypersensitivity among adults with asthma. The aim of this study was to explore the prevalence of self-reported adverse reactions and IgE sensitization to the different foods and to determine the spectrum and the prevalence of food-related gastrointestinal symptoms in adults with and with no asthma.

Methods

A cross sectional study based on interviews and questionnaire responses from 1527 subjects, aged 18–75 years of age, from Västra Götaland in Sweden, as part of the larger West Sweden Asthma Study. IgE analyses were performed in sera from all subjects.

Results

Fifty three percent of adults with asthma reported adverse reactions to foods compared to 30 % of non-asthmatics. Most asthmatics reported symptoms from eating hazelnut, followed by other nuts, birch-related foods, milk, peanut and shellfish. Furthermore, adults with asthma experienced significantly more often gastrointestinal symptoms from hazelnut, apple and milk and were found to significantly more often be sensitized to the most common foods compared to the non-asthmatic subjects. The asthmatics showed a significant correlation between IgE to both hazelnut and birch and self-reported symptoms after ingestion of hazelnut and to a lesser extent to almonds.

Conclusions

The prevalence of self-reported adverse reactions and sensitization to the most common foods was much higher among the asthmatic subjects. Hazelnut was the food that asthmatics most frequently experienced adverse reactions from, and the strong correlation between IgE to hazelnut and birch indicate that the observed adverse reactions are partly due to sensitization to allergens from the PR-10 family.

Electronic supplementary material

The online version of this article (doi:10.1186/s13601-015-0067-6) contains supplementary material, which is available to authorized users.

The development of a standardised diet history tool to support the diagnosis of food allergy

The disparity between reported and diagnosed food allergy makes robust diagnosis imperative. The allergy-focussed history is an important starting point, but published literature on its efficacy is sparse. Using a structured approach to connect symptoms, suspected foods and dietary intake, a multi-disciplinary task force of the European Academy of Allergy and Clinical Immunology developed paediatric and adult diet history tools. Both tools are divided into stages using traffic light labelling (red, amber and green). The red stage requires the practitioner to gather relevant information on symptoms, atopic history, food triggers, foods eaten and nutritional issues. The amber stage facilitates interpretation of the responses to the red-stage questions, thus enabling the practitioner to prepare to move forward. The final green stage provides a summary template and test algorithm to support continuation down the diagnostic pathway. These tools will provide a standardised, practical approach to support food allergy diagnosis, ensuring that all relevant information is captured and interpreted in a robust manner. Future work is required to validate their use in diverse age groups, disease entities and in different countries, in order to account for differences in health care systems, food availability and dietary norms.

High incidence and remission of reported food hypersensitivity in Swedish children followed from 8 to 12 years of age - a population based cohort study

BACKGROUND

Few population-based cohort studies have examined reported food hypersensitivity longitudinally. We investigated prevalence, incidence and remission of perceived food hypersensitivity among schoolchildren from 8 to 12 years of age, and risk factors associated with incidence and remission.

METHODS

A population-based cohort including all 7-8 year-old children in three Swedish towns was recruited in 2006. A total of 2,585 (96% of invited) children participated in a parental questionnaire. The children in two of the towns, n = 1,700 (90% of invited) also participated in skin-prick-testing with airborne allergens. The cohort was followed using the same methods at 11-12 years of age. At study follow up, specific IgE to foods was analyzed in a randomized subset of children (n = 652).

RESULTS

The prevalence of perceived food hypersensitivity increased from 21% at 8 years to 26% at 12 years of age. During this four-year-period, the cumulative incidence of food hypersensitivity was high (15%), as was remission (33%). This pattern was particularly evident for hypersensitivity to cow´s milk, while the incidence of hypersensitivity to other foods was lower. Female sex, allergic heredity, current rhinitis and allergic sensitization were associated with the incidence of food hypersensitivity and allergic sensitization was negatively associated with remission. Risk-factor-patterns for both incidence and remission were different for hypersensitivity to milk compared with hypersensitivity to other foods. Generally, the agreement between reported food hypersensitivity and IgE-sensitization to the implicated food was poor.

CONCLUSIONS

In this longitudinal, population-based cohort-study perceived food hypersensitivity was common among children between ages 8 and 12, often transient and not well correlated with food-specific IgE. While these findings suggest an overestimated prevalence of food hypersensitivity, the public-health-significance remains high as they reflect the perceived reality to which the children adapt their life and food intakes.

Food intolerance and allergy: increased incidence or contemporary inadequate diets?

PURPOSE OF REVIEW

The role of nutrients in the study of allergic disease has been studied for many years, but recent evidence suggests that it is the quality and variety of the whole diet which affects the development of food allergy. This review seeks to understand whether food allergy prevalence is increasing and the role of diet in the development of the disease.

RECENT FINDINGS

New data on the European and global prevalence of food allergy suggest that both reported and actual rates are increasing. Recent findings from studies in infants and children indicated that a Western diet could enhance the development of allergic disease, possibly due to an effect on the homeostasis of the gut microbiome, impacting the immune status of individuals.

SUMMARY

With overall prevalence rates for food allergy increasing, it is important to ascertain the relevance of dietary influences. Attention has shifted from single-nutrient prevention studies to evaluation of the effect of different dietary patterns on allergic outcomes. Evidence suggests that introduction of complementary foods should not be delayed, and the diversity of the diet in early life is important. The increasingly processed nature of the Western diet, in combination with influences on the gut microbiome, may contribute to the rising prevalence of allergic disease, including food allergy.