Management of food allergies

[Exceptional occupational allergies due to food of animal origin]

BACKGROUND

The food industry is a high-risk area for work-related allergic immediate skin reactions (contact urticaria, contact urticaria syndrome, protein contact dermatitis) with or without respiratory symptoms (allergic rhinitis, allergic asthma) due to proteins of animal origin.

OBJECTIVES

The present work gives an overview of allergenic seafood and meat proteins and their clinical and occupational relevance in different work settings.

METHODS

A review of current knowledge and a supplementary selective literature search were performed.

RESULTS

Protein contact dermatitis is one of the more common occupational dermatoses in workers exposed to seafood and meat, after irritant hand eczema. Fishermen, cooks, and butchers are most commonly affected. Crustaceans and mollusks are more frequent triggers of food allergies than fish and can in individual cases also be life threatening. In contrast, primary meat allergy is rare. Beef among mammals and chicken among birds are the most common triggers.

CONCLUSIONS

All employees with allergic immediate skin and/or respiratory reactions exposed to proteins of animal origin in the workplace should undergo a careful allergological workup at an early stage. Determination of the specific IgE plays a central role in confirming the diagnosis and it is of great importance in individual cases to include the suspected native material in the skin tests. The course of the disease is generally characterized by a poor prognosis and is commonly associated with a change in occupation.

Assessment of the effects of a work-related allergy to seafood on the reduction of earning capacity in the context of BK No. 5101

Fish, crustaceans, and mollusks are among the most potent allergenic foods of animal origin and are thus important triggers of work-related immediate-food allergies. In Germany, work-related seafood allergies are of great importance in the fishing and processing industries as well as in the areas of food preparation, food control, and food sales. There is no causal therapy of seafood allergy, only the strict and lifelong avoidance of allergens remains. The following recommendations serve to assess the impact of a seafood allergy with regard to the work opportunities ended by it for the assessment of the reduction of earning capacity (MdE (German for Minderung der Erwerbsfähigkeit)) in the context of the occupational disease number 5101 of the Annex to the German regulation for occupational diseases. As a special feature of work-related seafood allergy with regard to insurance law aspects, it must be taken into account that there is a potential risk of systemic reaction with subsequent multi-organ involvement. For the estimation of MdE in the general labor market, the impact of a seafood allergy can therefore be assessed, depending on its clinical severity, as generally “mild” to “severe” in justified individual cases.

Epidemiology and risk factors for eosinophilic esophagitis: lessons for clinicians

INTRODUCTION

The rapid expansion in the epidemiology of eosinophilic esophagitis (EoE) is being documented, along with cumulative research assessing environmental exposures associated with EoE and susceptibility due to genetic variants.

AREAS COVERED

Incidence rates for EoE of 5-10 new cases per 100,000 inhabitants annually have shown an increase in recent reports of up to 20 in some countries; the highest prevalence being reported for Europe and North America, where EoE now affects more than 1 out of 1,000 people. EoE has been shown to be associated with several disorders, Th2-mediated atopies being the most common. Patients with EoE exhibit increased frequency of asthma, allergic rhinitis and eczema, and EoE has been considered as a late component of the atopic march. Risk variants in TSLP, CAPN14 and LRCC32 genes, among others, have all been related to EoE, and interact with prenatal and early life exposure potentially modifying abundance and composition of gut microbiome. Dysregulated interactions between bacteria and mucosal immunity emerge as leading causes of EoE.

EXPERT OPINION

The expanding epidemiology of EoE, the resources needed and subsequent increasing healthcare costs require additional effort to optimize cost-effective management and unveil mechanisms that enhance the development of future preventive strategies.

[Seafood allergy in cooks: a case series and review of the literature]

BACKGROUND

Seafood is a very potent allergen. Epidemiological studies of seafood allergy in the highly exposed cooking profession are lacking. The objective of this first case series was to demonstrate the high relevance and consequences of seafood allergy in cooks. PATIENTS UND METHODS: Retrospective analysis of all the case files sent in which the presence of an occupational disease according to no. 5101 of the appendix of the German ordinance on industrial disease was to be clarified.

RESULTS

Thirty cooks (men 70 %) with an occupational seafood allergy were assessed between January 2008 and April 2014. Seafood allergy was observed in youngish workers(median age 24.7 yrs.) with an early manifestation of the disease (after 1.7 yrs. of occupation in median). In all except one (96.7 %) onset was localized on the hands.Most commonly documented were immediate sensitizations to cod, salmon, trout,and herring. Emergency treatment due to an anaphylactic shock at the workplace became necessary in 5 cases (16.7 %). In 27 cases (90 %) discontinuation of occupation was needed and was carried out after 6.3 yrs. of occupation in median.

CONCLUSIONS

Seafood allergy in cooks is mostly characterized by a quick progressive course of disease, already at the start of the cooking career. The prognosis for continuance in occupation is poor and an occupational disease is to be considered at a nearly stage. An emergency kit with an epinephrine auto-injector should be provided for life by the responsible accident insurer.

Histological findings in infants with Gastrointestinal food allergy are associated with specific gastrointestinal symptoms; retrospective review from a tertiary centre

BACKGROUND

Gastrointestinal food allergy (GIFA) occurs in 2 to 4 % of children, the majority of whom are infants (<1 year of age). Although endoscopy is considered the gold standard for diagnosing GIFA, it is invasive and requires general anaesthesia. Therefore, we aimed to investigate whether in infants with GIFA, gastrointestinal symptoms predict histological findings in order to help optimise the care pathway for such patients.

METHODS

All infants <1 year of age over a 20 year period who underwent an endoscopic procedure gastroscopy or colonoscopy for GIFA were evaluated for the study. Symptoms at presentation were reviewed and compared with mucosal biopsy histological findings, which were initially broadly classified for study purposes as "Normal" or "Abnormal" (defined as the presence of any mucosal inflammation by the reporting pathologist at the time of biopsy).

RESULTS

Of a total of 1319 cases, 544 fitted the inclusion criteria. 62 % of mucosal biopsy series in this group were reported as abnormal. Infants presenting with diarrhoea, rectal (PR) bleeding, irritability and urticaria in any combination had a probability >85 % (OR > 5.67) of having abnormal histological findings compared to those without. Those with isolated PR bleeding or diarrhoea were associated with 74 % and 68 % probability (OR: 2.85 and 2.13) of an abnormal biopsy, respectively. Conversely, children presenting with faltering growth or reflux/vomiting showed any abnormal mucosal histology in only 50.8 % and 45.3 % (OR: 1.04 and 0.82) respectively.

CONCLUSIONS

Food allergy may occur in very young children and is difficult to diagnose. Since endoscopy in infants has significant risks, stratification of decision-making may be aided by symptoms. At least one mucosal biopsy demonstrated an abnormal finding in around half of cases in this selected population. Infants presenting with diarrhoea, PR bleeding, urticaria and irritability are most likely to demonstrate abnormal histological findings.

Update on food allergy in adults

Though much has been studied and written about food allergy, the majority of the available literature focuses on food allergies in the pediatric population. Unfortunately, it is likely that in regard to food allergies, adults are not just big children, and extrapolating findings from pediatric to adult patient populations might lead to erroneous assumptions. Thus, it is important to validate the correlation between pediatric and adult data, gather data regarding adult food allergy and understand the specific nuances of subsets of adults to better treat their food allergy. This review was conducted by identifying potentially relevant studies regarding food allergies in adults through electronic databases, including PubMed, Medline, and Google Scholar. The search terms included "allergy", "food" and "adults". Parameters of 19+ years of age were added to search terms and all journals were written in or translated to English. From these search results, focus was placed on studies from 2010 to 2012. This systematic update on food allergy in adults found that the evidence regarding prevalence, diagnosis and management of food allergies is very limited, with the majority of data derived from children and young adults.

In Vitro Induction of Allergen-Specific Interleukin-10-Producing Regulatory B Cell Responses by Interferon-γ in Non-Immunoglobulin E-Mediated Milk Allergy

PURPOSE

Specific oral immunotherapy (SOIT) using interferon-γ (IFN-γ) has been successful as a food allergy treatment. Interleukin-10 (IL-10)-producing regulatory B cells (Br1s) play a role in immune tolerance to food allergens. In addition, IFN-γ shows tolerogenic effects on allergen-induced Br1 responses.

METHODS

Eleven patients that were allergic to cow's milk and 12 milk-tolerant subjects were selected by double-blind placebo-controlled food challenge (DBPCFC) and clinical characteristics. The immunomodulatory effects of IFN-γ on allergen-specific Br1 responses were evaluated in 6 milk allergy patients and 8 milk-tolerant subjects. Peripheral blood mononuclear cells (PBMCs) from subjects were stimulated with casein and/or IFN-γ and analyzed by flow cytometry.

RESULTS

IFN-γ had no effect on total cell counts or the proportion of Br1 cells in PBMCs. IFN-γ stimulation did not change total Br1 cell counts or the percentage of Br1s among CD5(+) B cells in the milk allergy or the milk-tolerant groups. In the milk allergy group, Br1 counts were not different between the control and the casein stimulation but significantly increased in the IFN-γ + casein stimulated cells, and the Br1 fractions were decreased after casein stimulation and recovered in the addition of IFN-γ for stimulation. In the milk-tolerant group, Br1 counts increased in the casein stimulated cells and in the IFN-γ + casein stimulated cells, but the increase was significantly less when IFN-γ was added, and the Br1 fractions were increased after casein stimulation and IFN-γ + casein stimulation, that was not significant when IFN-γ was added.

CONCLUSIONS

IFN-γ-induced allergen-specific Br1 responses in the PBMCs of milk allergy patients play a role in milk allergen-specific tolerance induction in vitro. Further investigations into the molecular immunological mechanisms underlying the induction of allergen-specific Br1 responses are needed.

Tolerogenic effects of interferon-gamma with induction of allergen-specific interleukin-10-producing regulatory B cell (Br1) changes in non-IgE-mediated food allergy

In this study, specific oral tolerance induction using interferon-gamma (IFN-γ) could successfully treat food allergies. Allergen-specific IL-10-producing regulatory B cell (Br1) responses are characteristic in immune tolerance of food allergies. The in-vivo effects of IFN-γ on allergen-induced changes in Br1 proportion and numbers in food allergies were investigated. Oral food challenges were conducted and 20 allergic patients to cow's milk were selected. Of these 20 patients, five were treated with IFN-γ and milk (SOTI group), five were treated with only milk, five were treated with only IFN-γ, and five did not receive any treatment. In addition, 10 milk-tolerant subjects were involved in this study. Peripheral blood mononuclear cells (PBMCs) were stimulated using casein and stained for CD5, CD19, annexin V, and IL-10 before and after treatment. Allergy tolerance was induced only in the SOTI group along with induction of allergen-induced Br1 changes. Thus, IFN-γ can show tolerogenic effects in vivo when introduced with an allergen, which may be at least partly due to its effect on allergen-induced Br1 responses.

A pilot study of interferon-gamma-induced specific oral tolerance induction (ISOTI) for immunoglobulin E-mediated anaphylactic food allergy

Food-induced anaphylaxis is a life-threatening, IgE-mediated disease. No specific therapeutic recommendations, aside from the avoidance of offending foods, exist at this time. However, specific oral tolerance induction for food allergy has been investigated by several groups. In this study, specific oral tolerance induction was attempted using interferon-gamma (IFN-gamma) as an adjuvant for IgE-mediated anaphylactic food allergies. A total of 25 patients with IgE-mediated anaphylactic food allergy to milk, eggs, or wheat were selected. IFN-gamma-induced specific oral tolerance induction (ISOTI) was conducted on 10 patients, while five patients were only treated with food, five patients received only IFN-gamma therapy, and five patients did not receive any treatment. Tolerance for IgE-mediated anaphylactic food allergy was successfully induced in all patients (10/10) with ISOTI, while no patients acquired tolerance for allergenic foods in the control groups. Food-specific IgE levels were increased, and skin prick test reactions significantly decreased after the completion of ISOTI. IFN-gamma-induced specific oral tolerance induction (ISOTI) is a promisingly effective treatment for IgE-mediated anaphylactic food allergy. IFN-gamma may be an important cytokine in tolerance induction. Simultaneous allergen stimulation with nonspecific immunomodulation of IFN-gamma was essential for specific tolerance induction in IgE-mediated anaphylactic food allergy.

[Prevalence of atopic eczema and nutritional factors in 6-7 year old children]

OBJECTIVES

To describe the prevalence of atopic eczema (AE) and to find the characteristics of the diet of children with AE.

DESIGN

Descriptive, transversal study.

SETTING

Primary schools.

MAIN MEASUREMENTS

The study used the standardized and validated questionnaire of the ISAAC phase III study, which finds the prevalence of AE in children and enables inter-centre comparison to be conducted. A questionnaire about food consumption was included. The prevalence ratio (PR) of AE and food consumption (95% confidence intervals) was calculated.

RESULTS

A total of 28 448 children aged 6-7 were included in the study. The prevalence of clinically diagnosed AE was 15.35% in boys and 15.24% in girls. The foods most often consumed were: dairy and cereals, followed by rice, pasta, and eggs. The least consumed were: butter, margarine, and fast food. The PR for children who consumed pasta was (PR=1.35), seafood (PR=1.28), cereals (PR=1.26), eggs (PR=1.13), and meat (PR=1.09).

CONCLUSIONS

The prevalence of AE in Spain was 15.3%, and was associated with food consumption. The consumption of dairy products, cereals, and olive oil was appropriate. The intake of fruit, vegetables, seafood, and legumes was below the recommended amounts. Future studies on the question are needed.

Influence of plant lipids on immune responses in mice to the major Brazil nut allergen Ber e 1

BACKGROUND

Lipids, particularly bacterial lipopolysaccharide, can impact on immune responses to proteins, with low doses enhancing type 2 responses.

OBJECTIVE

We have examined the influence of natural plant lipid extracts on antibody responses provoked in mice by recombinant Ber e 1, the major allergen in Brazil nuts.

METHODS

BALB/c strain mice were immunized (by intraperitoneal injection) with natural or recombinant Ber e l produced in Pichia pastoris and admixed with various lipid fractions isolated from Brazil nuts. Serum samples were analysed for specific IgE antibody by homologous passive cutaneous anaphylaxis assay and for IgG by enzyme-linked immunosorbant assay.

RESULTS

Exposure to recombinant (lipid-free) Ber e 1 alone failed to induce detectable IgG or IgE antibody. Co-administration of the total lipid fraction (with reduced triglyceride levels), sterol-rich, or polar lipid fractions, resulted in marked adjuvant effects on IgG and IgE. However, the beta-sitosterol and glycolipid-rich fractions were associated with only low-level IgG antibody, and had little impact on IgE antibody production. Natural Ber e 1 containing endogenous lipids also provoked IgG and IgE antibody responses. Identical IgE and IgG antibody responses were detected regardless of whether natural or recombinant Ber e 1 was used as substrates for analyses.

CONCLUSION

Endogenous Brazil nut lipids are required for the induction of optimal antibody responses to Ber e 1 in the BALB/c strain mouse. Appropriate antibody binding sites are present on both natural and recombinant forms of Ber e 1, suggesting that the impact of lipid is at the induction phase, rather than antibody recognition, and is possibly required for efficient antigen presentation.

Use of Amiodarone in a Patient With a Shellfish Allergy

A 65-year-old Caucasian male with a shellfish allergy developed atrial fibrillation and hypotension after coronary artery bypass and duodenal ulcer surgery. Following electrical cardioversion, oral amiodarone was continued chronically without an allergic reaction. There is a common misconception that a shellfish allergy correlates to an iodine allergy. There is little documentation of the association between an allergy to shellfish and an allergy to iodine. Food allergies can be subcategorized based on the involvement of IgE. Upon further investigation, it was discovered that shellfish allergies are not due to the iodine component, but rather, to a protein found in the shellfish. Amiodarone can be safely used in patients with shellfish allergies. A shellfish allergy does not necessarily imply an iodine allergy.

A mouse model for food allergy using intraperitoneal sensitization

Food allergy is an important health issue. With the increasing interest in novel foods derived from transgenic crop plants, there is a growing need for the development of approaches for the characterization of the allergenic potential of proteins. Although most foreign proteins are immunogenic (able to induce IgG antibody responses), relatively few are important food allergens with the capacity to provoke IgE antibody production. There is currently no validated animal model for the determination of allergenic potential of food proteins. One approach that appears to show some promise is outlined in the current chapter. BALB/c strain mice are immunized by intraperitoneal injection and the potential to cause allergenicity assessed as a function of the induction of specific IgE antibody, measured by homologous passive cutaneous anaphylaxis. Progress to date with this method is summarized, and comparisons are made with other experimental models, including considerations of route of exposure, use of adjuvants and selection of appropriate end points.

Characterisation of immune responses to food allergens in mice

There is considerable interest in the development and evaluation of approaches for the safety assessment of novel foods, and in particular in methods for characterisation of allergenic potential. One strategy that has found favour is a tiered approach in which the potential of novel proteins to induce allergic sensitisation is assessed based on considerations of stability of the protein in a simulated gastric juice and homology with, or structural similarity to, known allergens. Linked to such an approach may be evaluation of serological identity with proteins known to cause allergic disease. With the aim of supplementing such approaches with a more direct measurement of potential allergenic activity, attempts have been made to characterise the quality of immune responses elicited in BALB/c strain mice. Such evaluations comprise measurement of IgG and IgE antibody production and (to a lesser extent) of induced cytokine expression patterns. Investigations to date suggest that in mice proteins provoke variable immune responses, those with the potential to cause allergic sensitisation stimulating IgE (and IgG) antibody production. In contrast, non-allergenic, but nevertheless immunogenic, proteins are associated with IgG antibody responses in the absence of marked IgE production. Consistent with the selective activation of selective type 2 T lymphocyte responses, exposure of mice to allergenic protein is associated with preferential expression of IL-4, -5, -10 and -13. Collectively these data suggest that characterisation of the nature of immune response induced in mice by proteins may provide a useful adjunct or alternative to current strategies for the assessment of allergenic potential.