Advances in food allergy in 2015

Non-IgE-Mediated Gastrointestinal Food Protein-Induced Allergic Disorders. Clinical Perspectives and Analytical Approaches

Non-IgE-mediated gastrointestinal food allergy (non-IgE-GI-FA) is the name given to a series of pathologies whose main entities are food protein-induced allergic proctocolitis (FPIAP), food protein-induced enteropathy (FPE), and food protein-induced enterocolitis syndrome (FPIES). These are more uncommon than IgE-mediated food allergies, their mechanisms remain largely unknown, and their diagnosis is mainly done by clinical history, due to the lack of specific biomarkers. In this review, we present the latest advances found in the literature about clinical aspects, the current diagnosis, and treatment options of non-IgE-GI-FAs. We discuss the use of animal models, the analysis of gut microbiota, omics techniques, and fecal proteins with a focus on understanding the pathophysiological mechanisms of these pathologies and obtaining possible diagnostic and/or prognostic biomarkers. Finally, we discuss the unmet needs that researchers should tackle to advance in the knowledge of these barely explored pathologies.

Biologicals for the prevention of anaphylaxis

PURPOSE OF REVIEW

To review the use of biological agents (BA) in the treatment of anaphylaxis in the view of the new knowledge in the field to support the quality of care and prevention.

RECENT FINDINGS

Some BA, as a single medication or as combined therapy to food or venom immunotherapy, are effectively able to reduce most of the severe anaphylactic reactions.

SUMMARY

Anaphylaxis is a recognized clinical emergency, which requires prompt identification and treatment. Several biologic therapies and new devices are emerging as a potential preventive treatment for anaphylaxis. However, adrenaline (epinephrine) is still the first-line treatment for any type of anaphylaxis. Biological drugs, such as omalizumab, whereas not US Food and Drug Administration (FDA) nor European Medicines Agency (EMA) approved for anaphylaxis, have been used as therapeutic adjuvants in the preventive treatment of anaphylaxis, but cost-effectiveness should be considered individually.

Silkworm dropping extract regulates food allergy symptoms via inhibition of Th2-related responses in an ovalbumin-induced food allergy model

BACKGROUND

Silkworm droppings have long been used in traditional medicine to remedy allergic itching, palsy, blood circulation problems, and arthritis in Asian countries. To investigate the anti-allergic effect of silkworm dropping extract (SDE) and its mechanism, we used a mouse model of food allergy induced by ovalbumin (OVA).

RESULTS

SDE ameliorated the symptoms of OVA-induced food allergies, and the levels of T helper 2 (Th2)-related cytokines [such as interleukin (IL)-4, IL-5, IL-10, and IL-13] were found to be significantly decreased in both the spleen and mesenteric lymph nodes by SDE. Furthermore, SDE treatment directly inhibited OVA permeation, IL-4 production, and degranulation of mast cells; in contrast, immunoglobulin E (IgE) production from B cells was not affected.

CONCLUSION

These results suggest that SDE has potential anti-allergic activities, and SDE may be useful in the treatment/prevention of allergic disorders such as food allergies, serving as therapeutic agents. © 2019 Society of Chemical Industry.

Food allergy-From food avoidance to active treatment

The prevalence of food allergy (FA) has increased too rapidly, possibly due to environmental factors. The guidelines recommend strict allergen avoidance, but FA is still the main cause of anaphylaxis in all age groups. Immunotherapy is the only treatment able to change the course of allergic disease, and oral immunotherapy (OIT) is the more effective route in FA. However, it carries the risk of adverse reactions, including anaphylaxis. To improve OIT safety, adjuvant therapy with the immunoglobulin E (IgE) monoclonal antibody omalizumab has been extensively used. Results suggest particular benefit in patients with high risk of fatal anaphylaxis. An alternative approach is to use omalizumab instead of OIT to prevent severe allergic reactions upon accidental exposure. This paper reviews current evidence regarding IgE-mediated FA, focusing on natural tolerance and food sensitization acquisition, and on avoidance measures and their limitations.

Machine learning approach yields epigenetic biomarkers of food allergy: A novel 13-gene signature to diagnose clinical reactivity

Background

Current laboratory tests are less than 50% accurate in distinguishing between people who have food allergies (FA) and those who are merely sensitized to foods, resulting in the use of expensive and potentially dangerous Oral Food Challenges. This study presents a purely-computational machine learning approach, conducted using DNA Methylation (DNAm) data, to accurately diagnose food allergies and potentially find epigenetic targets for the disease.

Methods and results

An unbiased feature-selection pipeline was created that narrowed down 405,000+ potential CpG biomarkers to 18. Machine-learning models that utilized subsets of this 18-feature aggregate achieved perfect classification accuracy on completely hidden test cohorts (on an 8-fold hidden dataset). Ensemble classification was also shown to be effective for this High Dimension Low Sample Size (HDLSS) DNA methylation dataset. The efficacy of these machine learning classifiers and the 18 CpGs was further validated by their high accuracy on a large number of hidden data permutations, where the samples in the training, cross-validation, and hidden sets were repeatedly randomly allocated. The 18-CpG signature mapped to 13 genes, on which biological insights were collected. Notably, many of the FA-discriminating genes found in this study were strongly associated with the immune system, and seven of the 13 genes were previously associated with FA.

Conclusions

Previous studies have also created highly-accurate classifiers for this dataset, using both data-driven and a priori biological insights to construct a 96-CpG signature. This research builds on previous work because it uses a completely computational approach to obtain a perfect classification accuracy while using only 18 highly discriminating CpGs (0.005% of the total available features). In machine learning, simpler models, as used in this study, are generally preferred over more complex ones (other things being equal). Lastly, the completely data-driven methodology presented in this research eliminates the need for a priori biological information and allows for generalizability to other DNAm classification problems.

Prevalence of allergic diseases in children with inflammatory bowel disease

Introduction

There are many similarities between inflammatory bowel disease (IBD) and allergic diseases, including similar epidemiological data, pathomechanism, clinical course and even treatment methods. So far, many studies of IBD comorbidity with other diseases, including allergy, but mainly in adults, have been conducted.

Aim

To analyse the prevalence of allergic diseases, i.e. food allergy (FA), cow’s milk allergy (CMA), atopic dermatitis (AD), allergic rhinitis (AR) and asthma in children with IBD.

Material and methods

The study included 105 IBD patients from the Department of Paediatrics, Allergology and Gastroenterology of Collegium Medicum in Bydgoszcz and 100 children without IBD from the Outpatient Clinics. The authors applied the validated questionnaire as a study method.

Results

At least one allergic disease was found in 26 (43%) IBD children. The allergological diagnosis was made in IBD children more frequently than in the control group (p = 0.04). The difference was more noticeable with regards to skin prick tests (p = 0.02). FA was the most common disease; it was noted in 19 (32%) IBD children; followed by: AD – in 13 (22%), CMA – in 12 (20%), AR – in 10 (17%) and asthma – in 6 (10%) children. The prevalence of allergic diseases in the control and study groups was comparable (p > 0.05). There was no correlation between age of IBD children and allergy (p > 0.05). Asthma was significantly more common in children undergoing biological treatment (p = 0.01).

Conclusions

Children with IBD should be constantly monitored by medical professionals, not only due to the underlying disease but also due to a possible concomitant allergic disease.

Gut microbiota composition and butyrate production in children affected by non-IgE-mediated cow's milk allergy

Cow’s milk allergy (CMA) is one of the earliest and most common food allergy and can be elicited by both IgE- or non-IgE-mediated mechanism. We previously described dysbiosis in children with IgE-mediated CMA and the effect of dietary treatment with extensively hydrolyzed casein formula (EHCF) alone or in combination with the probiotic Lactobacillus rhamnosus GG (LGG). On the contrary, the gut microbiota in non-IgE-mediated CMA remains uncharacterized. In this study we evaluated gut microbiota composition and fecal butyrate levels in children affected by non-IgE-mediated CMA. We found a gut microbiota dysbiosis in non-IgE-mediated CMA, driven by an enrichment of Bacteroides and Alistipes. Comparing these results with those previously obtained in children with IgE-mediated CMA, we demonstrated overlapping signatures in the gut microbiota dysbiosis of non-IgE-mediated and IgE-mediated CMA children, characterized by a progressive increase in Bacteroides from healthy to IgE-mediated CMA patients. EHCF containg LGG was more strongly associated with an effect on dysbiosis and on butyrate production if compared to what observed in children treated with EHCF alone. If longitudinal cohort studies in children with CMA will confirm these results, gut microbiota dysbiosis could be a relevant target for innovative therapeutic strategies in children with non-IgE-mediated CMA.

Allergic gastroenteritis hospital admission time trends in Australia and New Zealand

AIM

Recent epidemiological studies indicate increases in hospital food allergy-related anaphylaxis admission rates in Australian and New Zealand. The aim of the study was to examine whether non-IgE-mediated food allergy might have increased in parallel.

METHODS

We analysed childhood hospital admissions rates by ICD 10 codes for allergic gastroenteritis (AG) and infective gastroenteritis in Australia and New Zealand between June 1998 and July 2014.

RESULTS

In Australia, most AG-related admissions (73%) occurred in those aged <1 year and increased by 7.3%/year (95% confidence interval (CI) 5.5-9.3, P < 0.0001) from 6.8 to 26.5/10⁵ population. Similar trends were observed for New Zealand; 81% of admissions occurred in those aged <1 year and increased by 9.4%/year (95% CI 5.5-9.3, P < 0.0001) from 7.2 to 30.7/10⁵ population. By contrast there were no significant changes in AG-related admission rates in the older patients and infective gastroenteritis admissions fell in both countries in those aged <1 year; Australia by 4.4%/year (95% CI 4.3-4.6, P < 0.0001) and in New Zealand by 5.8%/year (95% CI 5.4-6.2, P < 0.0001).

CONCLUSION

We observed a fourfold increase in AG-related admission rates in two countries with known high rates of IgE-mediated food allergy/anaphylaxis. If confirmed by other studies, it will be of interest to determine if factors thought to contribute to the increase in IgE-mediated food allergy might also play a role in non-IgE-mediated gastroenterological food allergy syndromes.

Peanut Allergy: An Epidemiologic Analysis of a Large Database

OBJECTIVE

To confirm new observations on peanut allergy and answer current concerns that families and healthcare providers have about peanut allergy.

STUDY DESIGN

Children who presented with a story of peanut allergy or peanut sensitization were asked to participate in a registry, which allowed an analysis focused on questions that a food allergy support group had about children with peanut allergy or sensitization.

RESULTS

A total of 1070 children were entered into the registry over 5 years. Two-thirds had a reaction to peanut. Children with peanut allergy were predominantly male (63%), white (78%), and with private health insurance (80%). Most reactions involved the skin (55%) and anaphylaxis occurred in 35%. The median age of a reaction was 1 year old. Atopic dermatitis was noted in 60% and asthma in 41%. Additional food allergy was noted in 58%. When second exposures occurred 28% had a more severe reaction. Skin test size did not differentiate the type of a reaction and children with anaphylaxis had slightly higher specific IgE levels. Severe reactions with inadvertent exposure in children who were peanut sensitized was rare (<1%).

CONCLUSIONS

The strategies for peanut allergy prevention and treatment have evolved. The data obtained in this large registry can answer many questions that families and healthcare providers have during this transition.

Home Remodeling and Food Allergy Interact Synergistically to Increase the Risk of Atopic Dermatitis

Purpose

The purpose of this study was to investigate the effects of home remodeling and food allergy (FA) on the development of atopic dermatitis (AD) in children.

Methods

The Modified International Study of Asthma and Allergies in Childhood questionnaire was used to survey 4,111 children recruited from 3 kindergartens and 6 elementary schools from Seongnam, Korea. Participants' parents agreed for them to participate in physical examinations, skin prick tests, and blood tests.

Results

Home remodeling in the past 12 months (adjusted odds ratio [aOR] 3.40, P = 0.006), lifetime diagnosis of FA (aOR 3.95, P < 0.001), parental history of AD (aOR 2.67, P = 0.001), and FA (aOR 2.35, P = 0.004) were independent risk factors for lifetime diagnosis of AD ever. When history of home remodeling and FA were combined, the risk for moderate-to-severe AD by scoring atopic dermatitis (SCORAD) score increased (aOR, 7.19, P = 0.011, P for interaction = 0.034).

Conclusion

Home remodeling, lifetime diagnosis of FA, parental history of AD, and parental history of FA were independent risk factors for AD. In addition, we observed a synergistic interaction between home remodeling and FA in the risk of moderate-to-severe AD.