9. Food allergy

Mechanisms and Health Aspects of Food Adulteration: A Comprehensive Review

Food adulteration refers to the alteration of food quality that takes place deliberately. It includes the addition of ingredients to modify different properties of food products for economic advantage. Color, appearance, taste, weight, volume, and shelf life are such food properties. Substitution of food or its nutritional content is also accomplished to spark the apparent quality. Substitution with species, protein content, fat content, or plant ingredients are major forms of food substitution. Origin misrepresentation of food is often practiced to increase the market demand of food. Organic and synthetic compounds are added to ensure a rapid effect on the human body. Adulterated food products are responsible for mild to severe health impacts as well as financial damage. Diarrhea, nausea, allergic reaction, diabetes, cardiovascular disease, etc., are frequently observed illnesses upon consumption of adulterated food. Some adulterants have shown carcinogenic, clastogenic, and genotoxic properties. This review article discusses different forms of food adulteration. The health impacts also have been documented in brief.

Advances in the Clinical Application of Histamine and Diamine Oxidase (DAO) Activity: A Review

The serum level of diamine oxidase (DAO) reflects the integrity and maturation of the small intestinal mucosa. This measure is important in diagnosing various diseases, including chronic urticaria tachyphylaxis, multiple organ dysfunction syndrome, preterm abortion, and migraine. This review aimed to summarize the findings of previous studies on the changes in DAO levels in diverse diseases and the application of this enzyme in the clinical setting, as well as the roles of this enzyme under physiological and pathological conditions. The advances in the mechanism and clinical application of DAO presented in this review will contribute to a better understanding of this enzyme and open up new and broader perspectives for future basic research and clinical applications.

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

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 The mechanisms of HFA and their frequency are difficult to precisely define, as most of the data come from outdated studies with poor methodology.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

Dietary Behavior and Risk of Orthorexia in Women with Celiac Disease

Evidence points to a link between celiac disease and eating disorders. Although with the current limited knowledge, orthorexia cannot be formally recognized as an eating disorder, some features are similar. This study is the first to examine individuals with celiac disease in terms of the prevalence of risk of orthorexia. Participants were 123 females diagnosed with celiac disease. The standardized ORTO-15 questionnaire was used to assess the risk of orthorexia. In this study, eating habits and physical activity were assessed. The effect of celiac disease on diet was self-assessed on a 5-point scale. Taking a score of 40 on the ORTO-15 test as the cut-off point, a risk of orthorexia was found in 71% of individuals with celiac disease, but only in 32% when the cut-off point was set at 35. There was a positive correlation between age and ORTO-15 test scores (rho = 0.30). In the group with orthorexia risk, meals were more often self-prepared (94%) compared to those without risk of orthorexia (78%) (p = 0.006). Individuals at risk for orthorexia were less likely to pay attention to the caloric content of food (46%) relative to those without risk of orthorexia (69%) (p = 0.001). For 64% of those at risk for orthorexia vs. 8% without risk had the thought of food that worried them (p = 0.001). Given the survey instrument for assessing the prevalence of orthorexia and the overlap between eating behaviors in celiac disease and orthorexia, the prevalence of orthorexia in celiac disease cannot be clearly established. Therefore, future research should focus on using other research tools to confirm the presence of orthorexia in celiac disease.

Chronic Milk-Dependent Food Protein-Induced Enterocolitis Syndrome in Children from West Pomerania Region

Characteristics of chronic milk-dependent food protein-induced enterocolitis syndrome (FPIES) in children from the region of Western Pomerania were studied. Prospectively, 55 children were diagnosed at a median of 2.2 months. The open food challenges (OFC), morphologies, milk-specific IgE (sIgE) (FEIA method, CAP system), and skin prick tests (SPTs) were examined. Vomiting and diarrhea escalated gradually but quickly led to growth retardation. Of the infants, 49% had BMI < 10 c, 20% BMI < 3 c; 25% had anemia, and 15% had hypoalbuminemia. During the OFCs we observed acute symptoms that appeared after 2-3 h: vomiting diarrhea and pallor. A total of 42% children required intravenous hydration. Casein hydrolysates or amino acids formulae (20%) were used in treatment. In 25% of children, SPT and milk sIgE were found, in 18%-other food SPTs, and in 14% allergy to other foods. A transition to IgE-dependent milk allergy was seen in 3 children. In the twelfth month of life, 62% of children had tolerance to milk, and in the twenty-fifth month-87%. Conclusions. Chronic milk-dependent FPIES resolves in most children. By the age of 2 children are at risk of multiple food sensitization, and those who have milk sIgE are at risk to transition to IgE-mediated milk allergy. Every OFC needs to be supervised due to possible severe reactions.

Global estimated Disability-Adjusted Life-Years (DALYs) of diarrheal diseases: A systematic analysis of data from 28 years of the global burden of disease study

BACKGROUND

Diarrheal disease (DD)-associated mortality has declined since 1990; however, the incidence of DD has experienced a less-pronounced decrease. Thus, it is important to track progress in managing DD by following loss of healthy years. A disability-adjusted life-year (DALY), which combines data on years-of-life lost (YLL) and years-lived with-disability (YLD), is a metric that can track such a burden.

METHODS AND FINDINGS

Using all 28 years of data in the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017, we compared DD DALYs among different demographic subsets including sex, age, country, and World Bank (WB) income level. We also evaluated DD DALYs as a function of the socio-demographic index (SDI), a measure of a region's socio-demographic development. On a global level, DD DALYs have decreased by approximately 85.43% from 1990 to 2017. Incidence and prevalence have decreased by 1.53% and 4.45%, respectively. A dramatic decrease in DD DALYs were observed for WB low-income countries, but not for WB high-income constituents. The temporal decrease in DD DALY rates in WB low-income countries was likely driven by a decrease in YLL. Alternatively, temporal increases in both YLL and YLD may have contributed to the apparent lack of progress in WB high-income countries. Regardless of WB income classification, children under the age of five and the elderly were the most vulnerable to DD. In nearly every year from 1990 to 2017, DD DALYs for females were higher than those for males in WB high-income regions, but lower than those for males in WB low-income constituents. The reason for these differences is not known. We also observed that the rate of DD DALYs was highly correlated to SDI regardless of WB income classification.

CONCLUSIONS

To the best of our knowledge, this is the only temporal study of DD DALYs that encompasses all 28 years of data available from the GBD. Overall, our analyses show that temporal reductions in DD DALYs are not equivalent across regions, sexes and age groups. Therefore, careful attention to local and demography-specific risk factors will be necessary to tailor solutions in region- and demography-specific manners.

Is Oral Food Challenge as Safe Enough as It Seems?

BACKGROUND

Oral food challenges (OFCs) assist in the diagnosis of food allergies and are essential to determine whether an allergy has been outgrown. During the OFC, a medical procedure e introduces foods suspected to be allergenic orally in increasing doses. Mild skin reactions such as urticaria or rarely serious life-threatening reactions such as anaphylaxis may develop.

OBJECTIVE

In this study, we aimed to retrospectively evaluate the clinical and laboratory characteristics of patients who experienced anaphylaxis during open OFCs in a tertiary care children's hospital.

METHODS

Patients who underwent OFCs to confirm the presence of a food allergy or to assess tolerance status at the University of Health Sciences, Ankara, Dr. Sami Ulus Maternity and Children Training and Research Hospital, Pediatric Allergy and Immunology Outpatient Clinic between 1 January 2013 and 1 February 2016, were included in the study. Patients' data were obtained retrospectively from electronic medical records and challenge chart reviews.

RESULTS

A total of 623 OFCs were performed during the period studied. Nine patients (1.4%) between 13 and 67 months of age (mean age: 38.3 months) developed anaphylaxis during their OFC.

CONCLUSION

OFCs should be performed in a hospital or outpatient office under medical supervision that is adequate for anaphylaxis intervention by an allergy specialist. Close observation of objective and subjective symptoms is essential during the challenge because there are no laboratory tests that can predict an anaphylactic diagnosis or the severity of the reaction.

Proven Food-Induced Acute Urticaria and Predictive Factors for Definitive Diagnosis in Childhood

BACKGROUND

Urticaria can be the only sign of a food allergy or can be seen together with other signs and symptoms of a food allergy.

OBJECTIVE

To determine the demographic, etiologic, and clinical features of food-induced acute urticaria in childhood.

METHODS

Patients suspected of food-induced acute urticaria were included in this prospective cross-sectional multicenter study.

RESULTS

Two hundred twenty-nine urticaria cases were included in this study. Seventeen patients who did not meet the inclusion criteria of the study were excluded. Of the 212 included cases, 179 (84.4%) were diagnosed with definitive food-induced acute urticaria. The most common foods causing acute urticaria were cow's milk, hen's eggs, and nuts in 56.4, 35.2, and 19% of cases, respectively. The positive predictive value of a history of milk-induced acute urticaria together with a milk-specific IgE >5 kU/L for cow's milk-induced acute urticaria was 92% (95% CI: 81-96%). A history of cow's milk-induced and/or hen's egg-induced acute urticaria was consistent with a definitive diagnosis of food-induced urticaria (Chen's kappa: 0.664 and 0.627 for milk and eggs, respectively). Urticaria activity scores were higher in patients with food-induced acute urticaria (p = 0.002).

CONCLUSION

Cow's milk, hen's eggs, and nuts were the most common allergens in the etiology of childhood food-induced acute urticaria. Although the urticaria activity score provides guidance for diagnosis, an oral food challenge is often essential for the definitive diagnosis of a patient with a history of food-induced acute urticaria.

Critical reviews and recent advances of novel non-thermal processing techniques on the modification of food allergens

Nowadays, the increasing prevalence of food allergy has become a public concern related to human health worldwide. Thus, it is imperative and necessary to provide some efficient methods for the management of food allergy. Some conventional processing methods (e.g., boiling and steaming) have been applied in the reduction of food immunoreactivity, while these treatments significantly destroy nutritional components present in food sources. Several studies have shown that novel processing techniques generally have better performance in retaining original characteristics of food and improving the efficiency of eliminating allergens. This review has focused on the recent advances of novel non-thermal processing techniques including high-pressure processing, ultrasound, pulsed light, cold plasma, fermentation, pulsed electric field, enzymatic hydrolysis, and the combination processing of them. Meanwhile, general information on global food allergy prevalence and food allergy pathology are also described. Hopefully, these findings regarding the modifications on the food allergens through various novel food processing techniques can provide an in-depth understanding in the mechanism of food allergy, which in turn possibly provides a strategy to adapt in the reduction of food immunoreactivity for the food industries.

Surface plasmon resonance (SPR) biosensors for food allergen detection in food matrices

Food allergies are recognized as a growing public health concern, with an estimated 3% of adults and 6-8% of children affected by food allergy disorders. Hence, food allergen detection, labeling, and management have become significant priorities within the food industry, and there is an urgent requirement for reliable, sensitive, and user-friendly technologies to trace food allergens in food products. In this critical review, we provide a comprehensive overview of the principles and applications of surface plasmon resonance (SPR) biosensors in the identification and quantification of food allergens (milk, egg, peanut, and seafood), including fiber-optic surface plasmon resonance (FOSPR), surface plasmon resonance imaging (SPRI), localized surface plasmon resonance (LSPR), and transmission surface plasmon resonance (TSPR). Moreover, the characteristics and fitness-for-purpose of each reviewed SPR biosensor is discussed, and the potential of newly developed SPR biosensors for multi-allergen real-time detection in a complex food system is highlighted. Such SPR biosensors are also required to facilitate the reliable, high-throughput, and real-time detection of food allergens by the food control industry and food safety control officials to easily monitor cross-contamination during food processing.

Antibiotic Exposure and the Risk of Food Allergy: Evidence in the US Medicaid Pediatric Population

BACKGROUND

Food allergy is a significant public health concern in the United States, especially in the pediatric population. It places substantial clinical and economic burdens on the health care system. Exposure to antibiotics in early childhood is thought to increase the risk of subsequent food allergy.

OBJECTIVE

To examine the impact of exposure to antibiotics early in life on time to development of food allergy.

METHODS

We conducted a population-based matched cohort study using Medicaid data from 28 states. Antibiotic nonusers were matched 1:1 to antibiotic users on date of birth, sex, race, and state. A Cox proportional hazards regression model was used to evaluate the effect of antibiotic exposure on time to development of food allergy. Sensitivity analyses were performed to assess the robustness of study findings.

RESULTS

We matched 500,647 antibiotic nonusers to 500,647 antibiotic users in the Medicaid pediatric population. In the adjusted Cox proportional hazards regression analysis, antibiotic exposure was significantly associated with faster development of food allergy (hazard ratio, 1.40; 95% CI, 1.34-1.45). The magnitude and significance of the association between antibiotic exposure and food allergy did not change in the sensitivity analyses. A significant association between antibiotic exposure and faster development of food allergy was found in 17 of 28 states.

CONCLUSION

Compared with antibiotic nonusers, children with antibiotic prescription had an increased risk of food allergy.

Gastrointestinal food allergy in Ghanaian children: a case series

Background

Food allergy is an adverse health effect arising from a specific immune response that occurs reproducibly on exposure to a given food. Food allergies are classified into three types: Ig(immunoglobulin)E mediated, mixed IgE and cell mediated and cell-mediated non IgE mediated. Gastrointestinal (GIT) food allergy has classically encompassed a number of different clinical entities: food protein-induced enterocolitis syndrome (FPIES), food protein-induced proctocolitis (FPIP), food protein-induced enteropathy and eosinophilic gastrointestinal disorders (EGID).

Case presentations

These are 5 cases of infants and toddlers who presented with various features of gastrointestinal food allergies, the commonest of which is lower gastrointestinal bleed. Two infants on exclusive breast feeding, presented with lower gastrointestinal bleeding and these resolved with maternal dietary milk and all dairy elimination. The third infant had rectal bleeding at age 6 months after the introduction of infant formula. The bleeding and eczema resolved with the introduction of hydrolyzed formula. One of the toddlers presented with severe eczema and malnutrition which improved with 6 food elimination. The last case had massive lower gastrointestinal bleed which resulted in hemicolectomy with no improvement until dietary elimination was instituted.

Conclusion

Gastrointestinal food allergy is not uncommon in children in Ghana. A high index of suspicion is required to make the right diagnosis, to minimize morbidity and unnecessary therapy.

Source of funding

None.

IgE-mediated food allergy

Food allergy is defined as an adverse immunologic response to a food protein. Food-related reactions are associated with a broad range of signs and symptoms that may involve any body system, including the skin, gastrointestinal and respiratory tracts, and cardiovascular system. Immunoglobulin E (IgE)-mediated food allergy is a leading cause of anaphylaxis and, therefore, referral to an allergist for timely and appropriate diagnosis and treatment is imperative. Diagnosis entails a careful history and diagnostic tests, such as skin prick tests, serum-specific IgE and, if indicated, an oral food challenge. Once the diagnosis of food allergy is confirmed, strict elimination of the offending food allergen from the diet is generally necessary; however, in the case of cow’s milk and egg allergy, many allergic children are able to eat these foods in their baked form. This article provides an overview of the epidemiology, pathophysiology, diagnosis, and management of IgE-mediated food allergy.

Is food protein induced enterocolitis syndrome only a non IgE-mediated food allergy?

Food protein induced enterocolitis syndrome (FPIES) is classified as non-IgE-mediated or cell-mediated food allergy, although there is an atypical phenotype so defined for the presence of specific IgEs. All diagnostic criteria for FPIES include the absence of skin or respiratory symptoms of IgE-mediated type. We present four cases that suggest that specific IgEs may have a pathogenic role, resulting in the existence of different FPIES phenotypes. This could be important from a diagnostic and therapeutic point of view.

Real-Time Food Authentication Using a Miniature Mass Spectrometer

Food adulteration is a threat to public health and the economy. In order to determine food adulteration efficiently, rapid and easy-to-use on-site analytical methods are needed. In this study, a miniaturized mass spectrometer in combination with three ambient ionization methods was used for food authentication. The chemical fingerprints of three milk types, five fish species, and two coffee types were measured using electrospray ionization, desorption electrospray ionization, and low temperature plasma ionization. Minimum sample preparation was needed for the analysis of liquid and solid food samples. Mass spectrometric data was processed using the laboratory-built software MS food classifier, which allows for the definition of specific food profiles from reference data sets using multivariate statistical methods and the subsequent classification of unknown data. Applicability of the obtained mass spectrometric fingerprints for food authentication was evaluated using different data processing methods, leave-10%-out cross-validation, and real-time classification of new data. Classification accuracy of 100% was achieved for the differentiation of milk types and fish species, and a classification accuracy of 96.4% was achieved for coffee types in cross-validation experiments. Measurement of two milk mixtures yielded correct classification of >94%. For real-time classification, the accuracies were comparable. Functionality of the software program and its performance is described. Processing time for a reference data set and a newly acquired spectrum was found to be 12 s and 2 s, respectively. These proof-of-principle experiments show that the combination of a miniaturized mass spectrometer, ambient ionization, and statistical analysis is suitable for on-site real-time food authentication.

New pharmaceutical approaches for the treatment of food allergies

INTRODUCTION

Allergic diseases constitute one of the most common causes of chronic illness in developed countries. The main mechanism determining allergy is an imbalance between Th1 and Th2 response towards Th2.

AREAS COVERED

This review describes the mechanisms underlying the natural tolerance to food components and the development of an allergic response in sensitized individuals. Furthermore, therapeutic approaches proposed to manage these abnormal immunologic responses food are also presented and discussed.

EXPERT OPINION

In the past, management of food allergies has consisted of the education of patients to avoid the ingestion of the culprit food and to initiate the therapy (e.g. self-injectable epinephrine) in case of accidental ingestion. In recent years, sublingual/oral immunotherapies based on the continuous administration of small amounts of the allergen have been developed. However, the long periods of time needed to obtain significant desensitization and the generation of adverse effects, limit their use. In order to solve these drawbacks, strategies to induce tolerance are being studied, such as the use of either adjuvant immunotherapy in order to facilitate the reversion of the Th2 response towards Th1 or the use of monoclonal antibodies to block the main immunogenic elements.

The influence of breast milk and infant formulae hydrolysates on bacterial adhesion and Caco-2 cells functioning

The aim of the study was to determine the concentration of BCM7 in human milk and infant formulae (IF) before and after eznymatic hydrolysis, and to evaluate the effect of obtained hydrolysates on interleukin-8 (IL-8) secretion and on proliferation of enterocytes in the in vitro model (Caco-2 cells). This study evaluates also the effect of hydrolysates on the adhesion of intestinal microbiota isolated from faeces of both healthy (H) and allergic (A) infants. In the study we investigated breast milk delivered by mothers of healthy ('healthy milk'; HM) and allergic ('allergic milk'; AM) infants. Three infant formulae were investigated: from hydrolysed cow casein (IF1), from hydrolysed cow whey (IF2) and from whole cow milk (IF3). Intestinal bacteria: Bifidobacterium, lactic acid bacteria, Enterobacteriaceae, Clostridium and Enterococcus were isolated from faeces of five healthy and five allergic infants. Mixtures of bacterial isolates and bacteria adhering to Caco-2 cells were characterised qualitatively with PCR-DGGE, and quantitavely with FISH. Concentration of BCM7 in breast milk and infant formulae was 1.6 to 8.9 times higher after enzymatic hydrolysis in comparison to undigested samples. The presence of this peptide resulted in alteration of intestinal epithelial proliferation and increase in secretion of IL-8. The quantitative profile of adherred bacteria applied as a mix of all isolates from healthy infants (H-MIX) was unchanged in the presence of HM hydrolysate and was modulated (increased number of beneficial Bifidobacterium and reduced commensal Enterobacteriaceae) in the presence of all IF hydrolysates. The presence of IF hydrolysates affected the profile of adhering isolates obtained from allergic infants (A-MIX) and reduced the adhesion of Enterobacteriaceae; the IF2 and IF3 hydrolysates decreased also the total number of adhering bacteria (TBN). However, a stimulating effect of AM hydrolysate on A-MIX adhesion (increased TBN) was observed.

Association of tree nut and coconut sensitizations

BACKGROUND

Coconut (Cocos nucifera), despite being a drupe, was added to the US Food and Drug Administration list of tree nuts in 2006, causing potential confusion regarding the prevalence of coconut allergy among tree nut allergic patients.

OBJECTIVE

To determine whether sensitization to tree nuts is associated with increased odds of coconut sensitization.

METHODS

A single-center retrospective analysis of serum specific IgE levels to coconut, tree nuts (almond, Brazil nut, cashew, chestnut, hazelnut, macadamia, pecan, pistachio, and walnut), and controls (milk and peanut) was performed using deidentified data from January 2000 to August 2012. Spearman correlation (ρ) between coconut and each tree nut was determined, followed by hierarchical clustering. Sensitization was defined as a nut specific IgE level of 0.35 kU/L or higher. Unadjusted and adjusted associations between coconut and tree nut sensitization were tested by logistic regression.

RESULTS

Of 298 coconut IgE values, 90 (30%) were considered positive results, with a mean (SD) of 1.70 (8.28) kU/L. Macadamia had the strongest correlation (ρ = 0.77), whereas most other tree nuts had significant (P < .05) but low correlation (ρ < 0.5) with coconut. The adjusted odds ratio between coconut and macadamia was 7.39 (95% confidence interval, 2.60-21.02; P < .001) and 5.32 (95% confidence interval, 2.18-12.95; P < .001) between coconut and almond, with other nuts not being statistically significant.

CONCLUSION

Our findings suggest that although sensitization to most tree nuts appears to correlate with coconut, this is largely explained by sensitization to almond and macadamia. This finding has not previously been reported in the literature. Further study correlating these results with clinical symptoms is planned.

The Effect of Wheat Allergy on the Course of Atopic Eczema in Patients over 14 Years of Age

Few studies concerning the importance of wheat allergy affecting the course of atopic eczema in adolescents and adult patients exist. Aim: The evaluation if wheat allergy can deteriorate the course of atopic eczema. Follow-up of patients with confirmed food allergy to wheat. Method: Altogether 179 persons suffering from atopic eczema were included in the study: 51 men and 128 women entered the study with an average age of 26.2 (s.d. 9.5 years) Dermatological and allergological examinations were performed, including skin prick tests, atopy patch tests, and specific serum IgE for wheat, open exposure test and double-blind, placebo-controlled food challenge test with wheat flour. Results: Wheat allergy affecting the coures of atopic eczema was confirmed in eight patients (4.5%) out of 179 patients enrolled in this study by double-blind, placebo controlled food challenge test. The course of atopic eczema showed a positive trend in patients with confirmed food allergy at 3, 6, 9, 12 month follow-up (statistical evaluation with paired t-test) after the elimination of wheat flour. Conclusion: Wheat allergy may play an important role in the worsening of atopic eczema (acting as a triggering exacerbating factor) only in a minority of adolescents and adult patients (4.5% in our study). The diagnostic methods (skin prick test, specific IgE, atopy patch test, history) cannot be used as separated tests for the determination of food allergy to wheat in patients with atopic eczema.Open exposure tests and double-blind, placebo-controlled food challenge should be used for the confirmation of wheat allergy affecting the course of atopic eczema.

Mouse models of food allergy: how well do they simulate the human disorder?

Food allergy is a growing health problem with serious concerns due to high potential for fatality. Rapid advances in the knowledge on causes and mechanisms as well as in developing effective prevention/therapeutic strategies are needed. To meet these goals, mouse models that simulate the human disorder are highly desirable. During the past decade, several mouse models of food allergies have been reported. Here, we briefly reviewed the human disorder and then critically evaluated these models seeking answers to the following important questions: To what extent do they simulate the human disorder? What are the strengths and limitations of these models? What are the challenges facing this scientific area? Our analysis suggest that: (i) the mouse models, with inherent strengths and limitations, are available for many major food allergies; there is scope for additional model development and validation; (ii) models mostly simulate the severe forms of human disorder with similar immune and clinical features; (iii) the approaches used to develop some of the mouse models may be questionable; and (iv) the specific mechanisms of sensitization as wells as oral elicitation of fatal reactions in both humans and mice remains incompletely understood and therefore warrants further research.

Food Protein-Induced Non-Immunoglobulin E-Mediated Allergic Colitis in Infants and Older Children: What Cytokines Are Involved?

BACKGROUND

Food protein-induced allergic proctocolitis (FPIAP) is mostly a non-immunoglobulin E-mediated disease where a T-cell-mediated reaction to cow's milk protein has been suggested. We determined the expression of transforming growth factor (TGF)-β, TGF-β receptor-1, tumor necrosis factor (TNF)-α, CD86, and CD23 on the colon mucosa to investigate their roles in the pathogenesis of the two subtypes of FPIAP, i.e. infantile FPIAP and FPIAP in older children.

METHODS

Group 1 comprised children with infantile FPIAP (age <6 months, n = 21), group 2 referred to FPIAP in older children (age >1.5 years, n = 7), and group 3 included children with juvenile hyperplastic polyps (n = 22). Immunohistochemical staining of colonic biopsy specimens was performed.

RESULTS

The expression of TNF-α was significantly higher in groups 1 and 2 compared to group 3. Group 2 patients had a significantly lower TGF-β expression compared to the other groups. The expression of CD86 was higher in group 1 than in group 3 (p = 0.012). Eosinophil counts per high-power field in the lamina propria were significantly correlated with CD86 expression (p = 0.026, r = 0.388).

CONCLUSION

Our results suggest that TNF-α is implicated in the pathogenesis of both types of FPIAP. The decreased activity of TGF-β receptor-1 accompanied by the increased expression of CD86 in infants and the decreased activity of TGF-β in older children appear to play a role in the development of FPIAP.

Influence of age on IgE response in peanut-allergic children and adolescents from the Mediterranean area

BACKGROUND

Peanut allergens are common triggers of food allergy. Analyses of sensitization patterns, relationships with other allergens, clinical symptoms, and variation with age are needed. We studied sensitization to Ara h 2, Ara h 9, and Pru p 3 in a peanut allergic children/adolescents and the relationship with peach and pollen.

METHODS

Peanut allergic patients aged between 1 and 20 years old were classified into two groups: A) allergic to peanut only and B) allergic to peach and peanut. The IgE response was measured to Ara h 2, Ara h 9, and Pru p 3.

RESULTS

Of 964 subjects evaluated, 28% were allergic to peanut. From this group, 68% were also sensitized to pollen. Urticaria was the most frequent entity followed by anaphylaxis and OAS. Fifty-eight percent had Ara h 2- and/or Ara h 9-specific IgE. More than half reported symptoms with peanut alone (Group A) and 35% to peanut and peach (Group B). We observed significant differences in sex, age, onset of symptoms, and sensitization to Artemisia between groups. IgE response to Ara h 2 was more frequent in Group A, and Ara h 9 and Pru p 3 in Group B. We observed a decrease in sensitization to Ara h 2 and an increase to Ara h 9 and Pru p 3 with increasing age.

CONCLUSION

Peanut allergy is frequent in subjects with allergy to plant foods, with Ara h 2 and Ara h 9 being two important allergens. In younger patients, Ara h 2 predominates over Ara h 9. The reverse was observed in older patients.

A retrospective study of peanut and tree nut allergy: Sensitization and correlations with clinical manifestations

Peanut (PN) and tree nut (TN) allergies are among the leading causes of fatal food-induced anaphylaxis and are increasing in prevalence, especially in children. Their cosensitization and concurrent clinical allergy have been understudied. This retrospective study investigated the correlation between PN and TN allergy, both in terms of in vitro sensitization (IVS) and clinical allergic manifestations. We conducted a retrospective medical record review at the Allergy Clinic at University Hospital of Brooklyn. Fourteen hundred six charts were reviewed, of which 76 (5.4%) had documented relevant clinical allergy: PN allergy but not TN allergy (n = 29) or TN allergy but not PN allergy (n = 11) or both (n = 30). Six patients with PN allergy but no TN exposure history were not included in the analysis. The majority of patients (67/76, 88.1%) had a concurrent history of asthma, rhinoconjunctivitis, or AD. Sensitivity of TN IVS predicting PN IVS was 38/39 (97%). Similarly, sensitivity of PN IVS predicting TN IVS was 38/42 (91%). Sensitivity of TN clinical allergy predicting PN allergy was 30/59 (51%). Sensitivity of PN clinical allergy predicting TN allergy was 30/41 (73%). The total number of organ systems involved in reported clinical reactions correlated with IVS to TN (p = 0.004) but not IVS to PN (p = 0.983). In summary, we found PN sensitization predicts TN sensitization in vitro, with lower predictability for clinical reactions.

The dichotomy of pathogens and allergens in vaccination approaches

Traditional prophylactic vaccination to prevent illness is the primary objective of many research activities worldwide. The golden age of vaccination began with an approach called variolation in ancient China and the evolution of vaccines still continues today with modern developments such as the production of Gardasil(TM) against HPV and cervical cancer. The historical aspect of how different forms of vaccination have changed the face of medicine and communities is important as it dictates our future approaches on both a local and global scale. From the eradication of smallpox to the use of an experimental vaccine to save a species, this review will explore these successes in infectious disease vaccination and also discuss a few significant failures which have hampered our efforts to eradicate certain diseases. The second part of the review will explore designing a prophylactic vaccine for the growing global health concern that is allergy. Allergies are an emerging global health burden. Of particular concern is the rise of food allergies in developed countries where 1 in 10 children is currently affected. The formation of an allergic response results from the recognition of a foreign component by our immune system that is usually encountered on a regular basis. This may be a dust-mite or a prawn but this inappropriate immune response can result in a life-time of food avoidance and lifestyle restrictions. These foreign components are very similar to antigens derived from infectious pathogens. The question arises: should the allergy community be focussing on protective measures rather than ongoing therapeutic interventions to deal with these chronic inflammatory conditions? We will explore the difficulties and benefits of prophylactic vaccination against various allergens by means of genetic technology that will dictate how vaccination against allergens could be utilized in the near future.

Detection of Caprine-specific Nucleic Acid Sequences in Goat Milk Using Polymerase Chain Reaction

Conflict of interest: none declared.

Atopy as a risk factor for thyroid autoimmunity in children affected with atopic dermatitis

BACKGROUND

As a result of several clinical reports addressing coincidence or coprevalence of atopy and autoimmune disease such as multiple sclerosis and type I diabetes mellitus, there has been considerable interest in defining the relationship between the expression of allergic and autoimmune disease in populations of patients. Although thyroid autoimmunity has been regularly associated with chronic urticaria in children, the cofrequency of thyroid autoimmunity and atopic dermatitis has not yet been investigated. The aim of the study was to describe our experience with children affected by atopic dermatitis and associated thyroid autoimmunity.

METHODS

From January 2010 to December 2012, 147 children affected by atopic dermatitis were consecutively referred to the Pediatric Clinic of the Pediatric Department at the Second University of Naples. Seventy healthy children of comparable ages, unaffected by atopic dermatitis, atopy or thyroid disease, served as a control group.

RESULTS

On the basis of skin prick test results we selected 54 IgE-mediated (36.7%) and 93 non-IgE-mediated AD (63.3%) children. Fourteen of 147 patients (9.52%) showed increased levels of antithyroid antibodies.

CONCLUSIONS

Our results therefore suggest that atopy, especially food allergy, and autoimmunity are two potential outcomes of dysregulated immunity.

Adverse reactions to foods and food allergy: development and reproducibility of a questionnaire for clinical diagnosis

Objective. To develop a questionnaire as a screening tool for adverse reactions to foods in children and to assess the technical reproducibility by test-retest. Methods. Reproducibility of the questionnaire was performed by the literature review, preparing the preliminary questionnaire, peer review, pretest, and retest analysis. The study of the test-retest reproducibility was cross-sectional and descriptive. Kappa coefficient was used to study the reproducibility of the questionnaire. The sample consisted of 125 2–4 year-old children from 15 daycare centers in Recife, Brazil, and interviews with parents or caregivers were used to collect data. Results. From the total children, sixty-three were boys (50.4%), forty-six were two years old (36.8%), forty-seven were three years old (37.6%), and thirty-two were four years old (25.6%). Forty caregivers reported that their child had health problems with food. Most frequently reported offending foods were milk, peanuts, shrimp, and chocolate. Nine questions showed a good Kappa index (≥0,6). Conclusions. The questionnaire used needs to be resized and reshaped on the basis of the issues with good internal consistency and reproducibility. The use of a validated and reproducible questionnaire in the children represents an important contribution towards assessing an eventual rise in overt food allergy.

Identification of rice proteins recognized by the IgE antibodies of patients with food allergies

Similarity among food allergens is a great problem affecting the specificity of diagnosis and treatment of allergic patients. We have observed that 80% of patients with food (including wheat) and pollen allergies have increased IgE antibodies against rice proteins. By immunoblotting, we documented that boiling decreased solubility and IgE reactivity of PBS-extracted rice and wheat proteins, yet in SDS extracts this reactivity was only slightly changed. The sera of patients highly positive on the IgE immunoblot and positive in basophil activation and skin prick test with boiled rice components were used for characterizing the IgE-binding proteins separated by 1D or 2D electrophoresis. Using mass spectrometry, we identified 22 rice SDS soluble proteins. Six of them were new thermostable potential rice allergens: glutelin C precursor, granule-bound starch synthase 1 protein, disulfide isomerase-like 1-1 protein, hypothetical protein OsI_13867, putative acid phosphatase precursor 1, and a protein encoded by locus Os02g0453600. All of the identified rice proteins differed from known wheat allergens, except proteins belonging to the α-amylase/trypsin inhibitor family. Furthermore, we would suggest that in patients with high IgE reactivity to wheat and rice components, the IgE immunoblot and skin prick test with boiled rice proteins could be beneficial before diet recommendation.

Gastrointestinal food allergy in infants

Food allergies are classified into three types, "IgE-mediated," "combined IgE- and cell-mediated" and "cell-mediated/non-IgE-mediated," depending on the involvement of IgE in their pathogenesis. Patients who develop predominantly cutaneous and/or respiratory symptoms belong to the IgE-mediated food allergy type. On the other hand, patients with gastrointestinal food allergy (GI allergy) usually develop gastrointestinal symptoms several hours after ingestion of offending foods; they belong to the cell-mediated/non-IgE-mediated or combined IgE- and cell-mediated food allergy types. GI allergies are also classified into a number of different clinical entities: food protein-induced enterocolitis syndrome (FPIES), food protein-induced proctocolitis (FPIP), food protein-induced enteropathy (Enteropathy) and eosinophilic gastrointestinal disorders (EGID). In the case of IgE-mediated food allergy, the diagnostic approaches and pathogenic mechanisms are well characterized. In contrast, the diagnostic approaches and pathogenic mechanisms of GI allergy remain mostly unclear. In this review, we summarized each type of GI allergy in regard to its historical background and updated clinical features, offending foods, etiology, diagnosis, examinations, treatment and pathogenesis. There are still many problems, especially in regard to the diagnostic approaches for GI allergy, that are closely associated with the definition of each disease. In addition, there are a number of unresolved issues regarding the pathogenic mechanisms of GI allergy that need further study and elucidation. Therefore, we discussed some of the diagnostic and research issues for GI allergy that need further investigation.

Stress and food allergy: mechanistic considerations

Recent years have seen a marked increase in food allergy prevalence among children, particularly in Western countries, that cannot be explained by genetic factors alone. This has resulted in an increased effort to identify environmental risk factors underlying food allergies and to understand how these factors may be modified through interventions. Food allergy is an immune-mediated adverse reaction to food. Consequently, considerations of candidate risk factors have begun to focus on environmental influences that perturb the healthy development of the emerging immune system during critical periods of development (eg, prenatally and during early childhood), particularly in the gut. Given that psychosocial stress is known to play an important role in other allergic and inflammatory diseases, such as asthma, its potential role in food allergy is a growing area of research. However, research to date has largely focused on animal studies. This review synthesizes relevant animal research and epidemiological data, providing proof of concept for moderating influences of psychological stress on food allergy outcomes in humans. Pathways that may underlie associations between psychosocial stress and the expression of food allergy are discussed.

Prevalence of confirmed IgE-mediated food allergy among adolescents in Turkey

BACKGROUND

Although food allergy is an important health problem in Western countries, the prevalence varies among geographic regions. There is limited data on the prevalence of food allergy especially for adolescent age group, and the data from Turkey and Mediterranean region are even scarce.

METHODS

The study is a cross-sectional survey including a questionnaire followed by phone survey with families that have reported food allergy and clinical evaluation of children having a history compatible with food allergy after phone survey. The sample number of students has been calculated 9096 of a total of 210.000 students at the second stage (6th, 7th, and 8th grades) of state elementary schools in the metropolitan counties of Ankara province with the assumption of food allergy prevalence (P) = 1% and a δ value = 0.2 (α < 0.05, β = 0.8).

RESULTS

Of 11,233 questionnaires distributed at 34 schools, 10,096 (89.4%) have been returned. The number of reported food allergy was 1139 (11.2%), and it was reduced to 133 (1.3%) after phone survey. After clinical evaluation by skin test, specific IgE and double-blind placebo-controlled food challenge (DBPCFC), proven IgE-mediated food allergy was determined in 15 (0.15%) children. The foods most commonly resulting food allergy were peanut 0.05% and treenuts 0.05%.

CONCLUSION

The prevalence of food allergy among adolescent age group has been confirmed to be comparatively low in Turkey. Peanuts and treenuts were determined to be the most common causes of IgE-mediated food allergy.

Interleukin 10 (IL10) and transforming growth factor β1 (TGFβ1) gene polymorphisms in persistent IgE-mediated cow's milk allergy

OBJECTIVES

The aim of this cross-sectional study was to evaluate whether interleukin 10 (IL10) and transforming growth factor β1 (TGFβ1) gene polymorphisms were associated with persistent IgE-mediated cow's milk allergy in 50 Brazilian children. The diagnostic criteria were anaphylaxis triggered by cow's milk or a positive double-blind, placebo-controlled food challenge. Tolerance was defined as the absence of a clinical response to a double-blind, placebo-controlled food challenge or cow's milk exposure.

METHOD

The genomic DNA of the 50 patients and 224 healthy controls (HCs) was used to investigate five IL10 gene polymorphisms (-3575A/T, -2849A/G, -2763A/C, -1082G/A, -592C/A) and one TGFβ1 polymorphism (-509C/T).

RESULTS

Among the five IL10 polymorphisms analyzed, homozygosis for the G allele at the -1082 position was significantly higher in the patients compared with the healthy controls (p=0.027) and in the persistent cow's milk allergy group compared with the healthy controls (p=0.001).

CONCLUSIONS

Homozygosis for the G allele at the IL10 -1082G/A polymorphism is associated with the persistent form of cow's milk allergy.

Food allergy: temporal trends and determinants

This review summarizes studies discussing temporal trends in the prevalence of food allergy as well as potential factors associated with the development of food allergy. In addition, we will address the potential hypotheses accounting for the apparent increase in food allergy prevalence. Studies suggest increased prevalence of food allergy. However, relatively little is known about its pathogenesis. This review aims to assess temporal trends in the prevalence of food allergy and discuss potential genetic, environmental, and demographic determinants. The search strategy examined the medical literature database MEDLINE (using PubMed) for the time period of January 1, 2002 to January 31, 2012. In recent decades, the prevalence of food allergy in general has increased by 0.60 % [95 % confidence interval (CI), 0.59 %-0.61 %] and the prevalence of peanut allergy by 0.027 % (95 % CI, 0.026 %-0.028 %), but it has now likely stabilized in developed countries. Genes, the environment, and demographic characteristics play a role in the pathogenesis of food allergy. Numerous environmental and demographic factors as well as gene-environment interactions may account for this increase in prevalence, but further studies are required to tease out their relative contribution.

A personalized food allergen testing platform on a cellphone

We demonstrate a personalized food allergen testing platform, termed iTube, running on a cellphone that images and automatically analyses colorimetric assays performed in test tubes toward sensitive and specific detection of allergens in food samples. This cost-effective and compact iTube attachment, weighing approximately 40 grams, is mechanically installed on the existing camera unit of a cellphone, where the test and control tubes are inserted from the side and are vertically illuminated by two separate light-emitting-diodes. The illumination light is absorbed by the allergen assay, which is activated within the tubes, causing an intensity change in the acquired images by the cellphone camera. These transmission images of the sample and control tubes are digitally processed within 1 s using a smart application running on the same cellphone for detection and quantification of allergen contamination in food products. We evaluated the performance of this cellphone-based iTube platform using different types of commercially available cookies, where the existence of peanuts was accurately quantified after a sample preparation and incubation time of ~20 min per test. This automated and cost-effective personalized food allergen testing tool running on cellphones can also permit uploading of test results to secure servers to create personal and/or public spatio-temporal allergen maps, which can be useful for public health in various settings.

Evaluation of cow's milk allergy in a large group of adolescent and adult patients with atopic dermatitis

Few studies concerning the occurrence of cow's milk allergy with the use of double-blind, placebo controlled food challenge test in adolescents and adult patients suffering from atopic dermatitis exist.

AIM

To evaluate the occurrence of cow's milk allergy in adolescents and adults suffering from atopic dermatitis.

METHOD

Altogether 179 persons suffering from atopic dermatitis were included in the study: 51 men and 128 women entered the study with the average age of 26.2 (s.d. 9.5 years). Complete dermatological and allergological examinations were performed.

RESULTS

The positive results in specific IgE and in skin prick tests were recorded in 12% of patients. According to the open exposure tests and double-blind, placebo controlled food challenge tests these patients are only sensitized to cow's milk without clinical symptoms of allergy. Double-blind, placebo controlled food challenge test confirmed food allergy to cow milk only in one patient (worsening of atopic dermatitis), the oral allergy syndrome was observed in another one patient, occurrence of this allergy was altogether 1.1%.

CONCLUSION

Cow's milk allergy rarely plays a role in the worsening of atopic dermatitis in adolescent and adult patients.

Anti-immunoglobulin e therapy

The importance of immunoglobulin E (IgE) in atopic disorders such as asthma, allergic rhinitis, food allergies, and atopic dermatitis is well established. Elevation of total serum IgE is typically found in many atopic patients, and in predisposed individuals, allergen-specific IgE is produced. The availability of humanized monoclonal antibodies against IgE has provided a new therapeutic option and tool to explore the role IgE in allergic diseases and the effects of inhibiting IgE itself. Omalizumab is a humanized, monoclonal antibody that recognizes and binds to the Fc portion of the IgE molecule. Administration of omalizumab results in a rapid and substantial decrease in free IgE in serum. Consequently, the activity of cell populations involved in allergic inflammation, including mast cells, eosinophils, basophils, and antigen-presenting cells, is affected as well. Clinically, anti-IgE therapy has already been proven to be useful in the treatment of asthma and allergic rhinitis. The aim of this review is to provide an overview of the mechanisms of action of anti-IgE therapy as well as its efficacy in the treatment of allergic diseases, especially asthma. Considerations regarding dosing and safety of omalizumab will be addressed as well.

Oral immunotherapy for milk allergy

BACKGROUND

The mainstay of treatment of IgE-mediated cow milk allergy (IMCMA) is an avoidance diet, which is especially difficult with a ubiquitous food like milk. Milk oral immunotherapy (MOIT) may be an alternative treatment, through desensitization or induction of tolerance.

OBJECTIVES

We aim to assess the clinical efficacy and safety of MOIT in children and adults with IMCMA as compared to a placebo treatment or avoidance strategy.

SEARCH METHODS

We searched 13 databases for journal articles, conference proceedings, theses and unpublished trials, without language or date restrictions, using a combination of subject headings and text words. The search is up-to-date as of October 1, 2012.

SELECTION CRITERIA

Only randomised controlled trials (RCT) were considered for inclusion. Blinded and open trial designs were included. Children and adults with IMCMA were included. MOIT administered by any protocol were included.

DATA COLLECTION AND ANALYSIS

A total of 2111 unique records were identified and screened for potential inclusion. Studies were selected, data extracted and methodological quality assessed independently by two reviewers. We attempted to contact the study investigators to inquire about data not published that was required for the analysis. Statistical heterogeneity was assessed using the I² test. We estimated a pooled risk ratio (RR) for each outcome using a Mantel-Haenzel fixed-effect model if statistical heterogeneity was low as evaluated by an I² value less than 50%.

MAIN RESULTS

Of 157 records reviewed, 16 were included, representing five trials. In general, the studies were small and had inconsistent methodological rigor. Overall, the quality of evidence was rated as low. Each study used a different MOIT protocol. A total of 196 patients were studied (106 MOIT, 90 control) and all were children. Three studies were blinded and two used an avoidance diet control.  Sixty-six patients (62%) in the MOIT group were able to tolerate a full serving of milk (about 200 mL) compared to seven (8%) of the control group (RR 6.61, 95% CI 3.51 to 12.44). In addition, 27 (25%) in the MOIT group could ingest a partial serving of milk (10 to 184 mL) while none could in the control group (RR 9.34, 95% CI 2.72 to 32.09). None of the studies assessed the patients following a period off immunotherapy. Adverse reactions were common (97 of 106 MOIT patients had at least one symptom), although most were local and mild. Because of variability in reporting methods, adverse effects could not be combined quantitatively. For every 11 patients receiving MOIT, one required intramuscular epinephrine. One patient required it on two occasions.

AUTHORS' CONCLUSIONS

Studies to date have involved small numbers of patients and the quality of evidence is generally low. The current evidence shows that MOIT can lead to desensitization in the majority of individuals with IMCMA although the development of long-term tolerance has not been established. A major drawback of MOIT is the frequency of adverse effects, although most are mild and self-limited. The use of parenteral epinephrine is not infrequent. Because there are no standardized protocols, guidelines would be required prior to incorporating desensitization into clinical practice.