Characteristics of childhood peanut allergy in the Australian Capital Territory, 1995 to 2007

Exploring the potential link between vegetable oil supplementation and adverse food reactions in dogs: a preliminary study

BACKGROUND

Adverse food reactions (AFR) are a common cause of skin diseases in dogs, with a prevalence of up to 24%. Research in humans and mice has shown that a high intake of vegetable oils rich in omega-6 polyunsaturated fatty acids (n-6 PUFA) can increase the risk and severity of allergic diseases. This study aimed to investigate the association between AFR and the supplementation of vegetable oils in the canine diet.

RESULTS

A total of 459 dogs were analyzed, with atopic dermatitis (22.66%) and adverse food reactions (AFR) (8.06%) being the most common diagnoses. Oil supplementation was recorded in 14.16% of dogs, with extra-virgin olive oil being the most common (70.77%). Dogs with AFR and concurrent AFR and CAD showed significantly higher oil supplementation rates compared to other conditions (P < 0.05; P < 0.001). No significant association was found between oil type and diagnosis (P = 0.563). After excluding EFA-supplemented dogs and those on prescription dermo diets, oil supplementation was still more prevalent in dogs with AFR compared to other conditions (29.31% vs. 10.10%, P < 0.001).

CONCLUSIONS

Vegetable oil supplementation was more frequent in dogs with AFR than in those with other dermatological conditions. This is the first study to evaluate the relationship between vegetable oil supplementation and AFR in dogs. While vegetable oil supplementation is associated with AFR, further studies are needed to establish causality and better understand the role of n-6 PUFA in the development of food allergies in dogs.

Dietary AGEs and food allergy: insights into the mechanisms of AGEs-induced food allergy and mitigation strategies

Food allergy (FA) is a significant public health concern, with over one billion individuals globally affected, and its prevalence continues to rise. Advanced glycation end products (AGEs) are common hazards in various diet. Recent investigations have shown that AGEs could influence the pathogenesis of FA by interacting with AGEs receptors. This paper provides a comprehensive review of recent advances on diet AGEs, summarized the mechanisms of AGEs in regulating food allergy and mitigation strategies, analyzed the limitations of current research on AGEs and prospected the future research. AGEs could combine with the receptors for AGEs (RAGE) to induce oxidative stress, inflammation and allergic signaling pathways. AGEs can affect allergen epitopes and conformation and regulate intestinal flora in a non-receptor-dependent manner, as well as affect the intestinal barrier and Th1/Th2 immune balance through receptor-dependent pathways to regulate food allergy. Currently, the approaches to reduce the AGEs-induced food allergy mainly depended on improving food processing methods (e.g., low temperature, short time, low pH and non-thermal processing methods), natural AGEs inhibitors and RAGE inhibitors. This review elucidates the influences of AGEs on food allergy and mitigation strategies, which could provide novel insights into reducing food allergy induced by diet AGEs.

Advances in Simple and Chiral-HPLC Methods for Antiallergic Drugs and Chiral Recognition Mechanism

Among many diseases, allergy appears to be a serious problem for human beings. Various forms of allergic disorders make people tense, leading to some other health issues. Many medications, including nonracemic and racemic ones, are used to treat this problem. It is important to have exact analysis strategies just to see any medication side effects, plasma profiles, and working efficiency. Therefore, efforts are made to review simple and chiral HPLC methods for antiallergic drugs; HPLC is the best analytical technique. The highlights in this article include the world scenario, causes of allergy, the effect of allergy on the economy, the mechanism of allergy in humans, classes of antiallergic drugs, simple drugs, chiral drugs, analysis by HPLC, and the chiral recognition mechanism. Moreover, attempts are also made to highlight the management of allergies and future perspectives.

Relevance of Early Introduction of Cow’s Milk Proteins for Prevention of Cow’s Milk Allergy

Food allergy incidence has increased worldwide over the last 20 years. For prevention of food allergy, current guidelines do not recommend delaying the introduction of allergenic foods. Several groundbreaking studies, such as the Learning Early About Peanut Allergy study, showed that the relatively early introduction of this allergenic food between 4–6 months of age reduces the risk of peanut allergy. However, less is known about the introduction of cow’s milk, as many children already receive cow’s-milk-based formula much earlier in life. This can be regular cow’s milk formula with intact milk proteins or hydrolyzed formulas. Several recent studies have investigated the effects of early introduction of cow’s-milk-based formulas with intact milk proteins on the development of cow’s milk allergy while breastfeeding. These studies suggest that depending on the time of introduction and the duration of administration of cow’s milk, the risk of cow’s milk allergy can be reduced (early introduction) or increased (very early introduction followed by discontinuation). The aim of this narrative review is to summarize these studies and to discuss the impact of early introduction of intact cow’s milk protein—as well as hydrolyzed milk protein formulas—and the development of tolerance versus allergy towards cow’s milk proteins.

The global burden of illness of peanut allergy: A comprehensive literature review

Peanut allergy (PA) currently affects approximately 2% of the general population of Western nations and may be increasing in prevalence. Patients with PA and their families/caregivers bear a considerable burden of self‐management to avoid accidental peanut exposure and to administer emergency medication (adrenaline) if needed. Compared with other food allergies, PA is associated with higher rates of accidental exposure, severe reactions and potentially fatal anaphylaxis. Approximately 7%–14% of patients with PA experience accidental peanut exposure annually, and one‐third to one‐half may experience anaphylaxis, although fatalities are rare. These risks impose considerably high healthcare utilization and economic costs for patients with PA and restrictions on daily activities. Measures to accommodate patients with PA are often inadequate, with inconsistent standards for food labelling and inadequate safety policies in public establishments such as restaurants and schools. Children with PA are often bullied, resulting in sadness, humiliation and anxiety. These factors cumulatively contribute to significantly reduced health‐related quality of life for patients with PA and families/caregivers. Such factors also provide essential context for risk/benefit assessments of new PA therapies. This narrative review comprehensively assessed the various factors comprising the burden of PA.

A novel patient-reported outcomes instrument assessing the side effects of peanut oral immunotherapy

BACKGROUND

Patients treated with peanut oral immunotherapy (OIT) may experience adverse reactions, particularly during up-dosing.

OBJECTIVE

To develop the Side Effects of Peanut Oral Immunotherapy Diary (SEPOD), an electronic questionnaire assessing the daily side effects of peanut OIT in clinical trials.

METHODS

Content and design of the SEPOD were informed by empirical literature review and meetings with 3 allergy-immunology experts. Interviews to confirm content and inform revisions were conducted in 24 pediatric patients with peanut allergy (14 treated with peanut OIT) aged 6 to 17 years; children aged 6 to 11 years were interviewed with their caregiver.

RESULTS

The SEPOD was drafted after literature review and expert interviews; the initial measurement approach comprised 2 SEPOD versions, a patient-reported outcome (PRO) version for children aged 12 to 17 years, and a caregiver-administered PRO version for children aged 6 to 11 years with instructions for caregiver questionnaire administration. Pediatric patients were expected to respond independently on both versions. Patient interviews indicated that some younger children (ie, aged 6-8 years) had difficulty understanding questions, even when reading aloud; therefore, a caregiver-administered outcome version, identical in content to the caregiver-administered PRO version, was developed for this age group. The final electronic SEPOD covered 23 peanut OIT side effects within the following 7 domains: gastrointestinal, dermatologic, itching, nasal, and respiratory, swelling (eyelid or periorbital, lip, tongue, and throat), pain (tongue, mouth, and throat), and dizziness.

CONCLUSION

This study yielded the SEPOD, a new clinical outcome assessment instrument with various methods of administration that can be used to assess the side effects of peanut OIT experienced by pediatric patients in a clinical trial setting.

Predictors of Food Sensitization in Children and Adults Across Europe

BACKGROUND

The geographical variation and temporal increase in the prevalence of food sensitization (FS) suggest environmental influences.

OBJECTIVE

To investigate how environment, infant diet, and demographic characteristics, are associated with FS in children and adults, focusing on early-life exposures.

METHODS

Data on childhood and adult environmental exposures (including, among others, sibship size, day care, pets, farm environment, and smoking), infant diet (including breast-feeding and timing of introduction to infant formula and solids), and demographic characteristics were collected from 2196 school-age children and 2185 adults completing an extensive questionnaire and blood sampling in the cross-sectional pan-European EuroPrevall project. Multivariable logistic regression was applied to determine associations between the predictor variables and sensitization to foods commonly implicated in food allergy (specific IgE ≥0.35 kU_A/L). Secondary outcomes were inhalant sensitization and primary (non-cross-reactive) FS.

RESULTS

Dog ownership in early childhood was inversely associated with childhood FS (odds ratio, 0.65; 95% CI, 0.48-0.90), as was higher gestational age at delivery (odds ratio, 0.93 [95% CI, 0.87-0.99] per week increase in age). Lower age and male sex were associated with a higher prevalence of adult FS (odds ratio, 0.97 [95% CI, 0.96-0.98] per year increase in age, and 1.39 [95% CI, 1.12-1.71] for male sex). No statistically significant associations were found between other evaluated environmental determinants and childhood or adult FS, nor between infant diet and childhood FS, although early introduction of solids did show a trend toward prevention of FS.

CONCLUSIONS

Dog ownership seems to protect against childhood FS, but independent effects of other currently conceived environmental and infant dietary determinants on FS in childhood or adulthood could not be confirmed.

The pertussis hypothesis: Bordetella pertussis colonization in the etiology of asthma and diseases of allergic sensitization

Decades of peer reviewed evidence demonstrate that: 1)Bordetellapertussisand pertussis toxin are potent adjuvants, inducing asthma and allergic sensitization in animal models of human disease, 2)Bordetella pertussisoften colonizes the human nasopharynx, and is well documented in highly pertussis-vaccinated populations and 3) in children, a history of whooping cough increases the risk of asthma and allergic sensitization disease. We build on these observations with six case studies and offer a pertussis-based explanation for the rapid rise in allergic disease in former East Germany following the fall of the Berlin Wall; the current asthma, peanut allergy, and anaphylaxis epidemics in the United States; the correlation between the risk of asthma and gross national income per capita by country; the lower risk of asthma and allergy in children raised on farms; and the reduced risk of atopy with increased family size and later sibling birth order. To organize the evidence for the pertussis hypothesis, we apply the Bradford Hill criteria to the association between Bordetella pertussisand asthma and allergicsensitization disease. We propose that, contrary to conventional wisdom that nasopharyngealBordetella pertussiscolonizing infections are harmless, subclinicalBordetella pertussiscolonization is an important cause of asthma and diseases of allergic sensitization.

Implementation of an Allergic Reaction Reporting Tool for School Health Personnel: A Pilot Study of Three Chicago Schools

Food allergy (FA) impacts 8% of U.S. children, thus it is critical to document allergic reactions to assist schools in managing FAs. We implemented and evaluated an online tool to assist school health personnel in tracking the characteristics of allergic reactions occurring at schools. The Online School Allergic Reaction Registry (OScARR) was modified from the Epinephrine Administration Form developed by the Massachusetts Department of Public Health, adapted for integration into existing school health records, and implemented in three Chicago schools during the 2016–2017 school year. All allergic reactions occurring at participating schools were recorded by school nurses. Twenty-five percent of the 20 allergic reactions reported were characterized as anaphylaxis by school nurses. School nurses reported that they would recommend OScARR for use in other schools. Detailed data obtained from three Chicago schools underscore the importance of proper documentation to improve the understanding of the causative allergen and location and management of allergic reactions in schools.

Death by food

Although death from food is not an uncommon finding in forensic facilities worldwide, the range of underlying lethal mechanisms and associated conditions that should be sought at the time of autopsy is quite disparate. Deaths may occur from i) infectious agents including bacteria, viruses, protozoa, cestodes, nematodes and prions; ii) natural toxins including amanita toxins, tetrodotoxin, ciguatera and scombroid; iii) anaphylaxis; iv) poisoning; v) mechanical issues around airway and gut obstruction and/or perforation; and vi) miscellaneous causes. Food-related deaths are important in terms of global mortality, and thus autopsies need to be comprehensive with full ancillary testing. Medicolegal matters may involve issues concerning likely exposure to infectious agents, possible foods ingested, the declared content and possible components of food, the significance of toxicological analyses, and aspects of duty of care in cases of café coronary syndrome and gastroenteritis while in care.

Parent-reported prevalence of food allergy in Mexican schoolchildren: A population-based study

BACKGROUND

Food allergy (FA) prevalence is well documented in developed countries and appears to be increasing, but remains unknown in most Latin American countries. We aimed to evaluate on a population basis the parent-reported prevalence of FA and its clinical characteristics in Mexican schoolchildren.

METHODS

A validated Spanish version of a structured written questionnaire was administered to parents of schoolchildren aged 5-13 years old from Culiacan, Mexico.

RESULTS

A total of 1049 parents responded to the survey (response rate, 84%). The estimated prevalence rates (95% CI) were: adverse food reactions 10.0% (8.3-11.9), "perceived FA, ever" 5.5% (4.3-7.0), "physician-diagnosed FA, ever" 4.9% (3.7-6.3), "immediate-type FA, ever" 4.4% (3.3-5.8), "immediate-type FA, current" 3.5% (2.6-4.8), and anaphylaxis 1.2% (0.72-2.1). Immediate hypersensitivity reactions were mainly triggered by the consumption of shrimp (1.3%), other shellfish (0.7%), strawberry (0.6%), chocolate (0.5%), and egg (0.4%). Schoolchildren with "immediate-type FA, current" had more atopic dermatitis and allergic rhinitis (p<0.05), but not asthma or drug allergy (p>0.05) than children without FA. All cases of anaphylaxis sought medical attention, but only one child had physician-diagnosed anaphylaxis and was advised to acquire an epinephrine autoinjector.

CONCLUSIONS

The prevalence of "immediate-type FA, current" to any food is 3.5% in Mexican schoolchildren. The poor recognition of anaphylaxis and the low frequency of prescription of epinephrine autoinjectors suggest that acute food-induced allergic reactions are not optimally managed in Mexico.

Combined blockade of the histamine H1 and H4 receptor suppresses peanut-induced intestinal anaphylaxis by regulating dendritic cell function

BACKGROUND

Signaling through histamine receptors on dendritic cells (DCs) may be involved in the effector phase of peanut-induced intestinal anaphylaxis.

OBJECTIVES

The objective of this study was to determine the role of histamine H1 (H1R) and H4 receptors (H4R) in intestinal allergic responses in a model of peanut allergy.

METHODS

Balb/c mice were sensitized and challenged with peanut. During the challenge phase, mice were treated orally with the H1R antagonist, loratadine, and/or the H4R antagonist, JNJ7777120. Bone marrow-derived DCs (BMDCs) were adoptively transferred to nonsensitized WT mice. Symptoms, intestinal inflammation, and mesenteric lymph node and intestine mucosal DCs were assessed. Effects of the drugs on DC chemotaxis, calcium mobilization, and antigen-presenting cell function were measured.

RESULTS

Treatment with loratadine or JNJ7777120 individually partially suppressed the development of diarrhea and intestinal inflammation and decreased the numbers of DCs in the mesenteric lymph nodes and lamina propria. Combined treatment with both drugs prevented the development of diarrhea and intestinal inflammation. In vitro, the combination suppressed DC antigen-presenting cell function to T helper cells and DC calcium mobilization and chemotaxis to histamine.

CONCLUSION

Blockade of both H1R and H4R in the challenge phase had additive effects in preventing the intestinal consequences of peanut sensitization and challenge. These effects were mediated through the limitation of mesenteric lymph node and intestinal DC accumulation and function. Identification of this histamine H1R/H4R-DC-CD4⁺ T-cell axis provides new insights into the development of peanut-induced intestinal allergic responses and for prevention and treatment of peanut allergy.

Cross-sensitization profiles of edible nuts in a birch-endemic area

BACKGROUND

Sensitization to birch pollen causes cross-sensitization to nuts, but rarely leads to clinical nut allergy. The aim was to study sensitizations to nuts in individuals sensitized to birch pollen and examine cross-reactivities between birch and nut species.

METHODS

All subjects with skin prick tests (SPTs) for birch pollen conducted during 1997-2013 in the Skin and Allergy Hospital in Helsinki (n = 114 572) and their available SPTs for nuts (n = 50 604) were included. Nut sensitizations were analyzed both with and without cosensitization to birch and stratified into age-categories. Cross-reactivities were analyzed with hierarchical clustering. One group of 1589 patients was surveyed for symptoms. Data were gathered also from Lapland to examine sensitizations in an area with less birch-pollen exposure.

RESULTS

Of subjects with birch sensitization, 84% were cosensitized to hazelnut, 71% to almond, and 60% to peanut. In a subgroup without birch sensitization, young children (<5 years) were most commonly nut-sensitized (8-40%); and this prevalence decreased in adolescents and further in adults (4-12%). Cashew and pistachio (ρ = 0.66; P < 0.001) and pecan and walnut (ρ = 0.65; P < 0.001) correlated the strongest. The majority of nut-sensitized patients (71% hazelnut, 83% almond, 73% peanut) reported no or mild symptoms. Cosensitizations between nuts and birch were similar in Lapland with its lower birch-pollen exposure.

CONCLUSION

Birch-sensitized individuals are frequently cosensitized to hazelnut, almond, and peanut. Among the birch-negatives, prevalences of nut sensitizations decrease from early childhood to adolescence. Cashew and pistachio, and pecan and walnut cross-react the most.

Role of Maternal Dietary Peanut Exposure in Development of Food Allergy and Oral Tolerance

BACKGROUND

The impact of maternal ingestion of peanut during pregnancy and lactation on an offspring's risk for peanut allergy is under debate.

OBJECTIVE

To investigate the influence of maternal dietary peanut exposure and breast milk on an offspring's allergy risk.

METHODS

Preconceptionally peanut-exposed C3H/HeJ females were either fed or not fed peanut during pregnancy and lactation. The offsprings' responses to peanut sensitization or oral tolerance induction by feeding antigen prior to immunization were assessed. We also assessed the impact of immune murine milk on tolerance induction pre- or post-weaning. For antigen uptake studies, mice were gavaged with fluorescent peanut in the presence or absence of immune murine milk; Peyer's patches were harvested for immunostaining.

RESULTS

Preconceptional peanut exposure resulted in the production of varying levels of maternal antibodies in serum (and breast milk), which were transferred to the offspring. Despite this, maternal peanut exposure either preconceptionally or during pregnancy and lactation, when compared to no maternal exposure, had no impact on peanut allergy. When offspring were fed peanut directly, dose-dependent tolerance induction, unaltered by maternal feeding of peanut, was seen. Although peanut uptake into the gut-associated lymphoid tissues was enhanced by immune milk as compared to naïve milk, tolerance induction was not affected by the co-administration of immune milk either pre- or post-weaning.

CONCLUSION

Maternal peanut exposure during pregnancy and lactation has no impact on the development of peanut allergy in the offspring. Tolerance to peanut can be induced early, even pre-weaning, by giving moderate amounts of peanut directly to the infant, and this is neither enhanced nor impaired by concurrent exposure to immune milk.

World Health Organization estimates of the global and regional disease burden of four foodborne chemical toxins, 2010: a data synthesis

Background Chemical exposures have been associated with a variety of health effects; however, little is known about the global disease burden from foodborne chemicals. Food can be a major pathway for the general population's exposure to chemicals, and for some chemicals, it accounts for almost 100% of exposure.  Methods and Findings Groups of foodborne chemicals, both natural and anthropogenic, were evaluated for their ability to contribute to the burden of disease.  The results of the analyses on four chemicals are presented here - cyanide in cassava, peanut allergen, aflatoxin, and dioxin.  Systematic reviews of the literature were conducted to develop age- and sex-specific disease incidence and mortality estimates due to these chemicals.  From these estimates, the numbers of cases, deaths and disability adjusted life years (DALYs) were calculated.  For these four chemicals combined, the total number of illnesses, deaths, and DALYs in 2010 is estimated to be 339,000 (95% uncertainty interval [UI]: 186,000-1,239,000); 20,000 (95% UI: 8,000-52,000); and 1,012,000 (95% UI: 562,000-2,822,000), respectively.  Both cyanide in cassava and aflatoxin are associated with diseases with high case-fatality ratios.  Virtually all human exposure to these four chemicals is through the food supply.  Conclusion Chemicals in the food supply, as evidenced by the results for only four chemicals, can have a significant impact on the global burden of disease. The case-fatality rates for these four chemicals range from low (e.g., peanut allergen) to extremely high (aflatoxin and liver cancer).  The effects associated with these four chemicals are neurologic (cyanide in cassava), cancer (aflatoxin), allergic response (peanut allergen), endocrine (dioxin), and reproductive (dioxin).

Engineering the Microbiome: a Novel Approach to Immunotherapy for Allergic and Immune Diseases

The incidence of immune disorders is growing parallel with practices associated with westernization, such as dietary changes, increased use of antibiotics, or elevated rates of Cesarean section. These practices can significantly impact the gut microbiota, the collection of bacteria residing in the human gastrointestinal tract, and subsequently disrupt the delicate balance existing between commensal flora and host immune responses. Restoring this balance by modifying the microbiota has thus emerged as a promising therapeutic approach. Here, we discuss the interaction between gut commensals and immunity, along with the potential of different interventions on the microbiota as treatment for inflammatory and allergic diseases.

ASCIA guidelines for prevention of anaphylaxis in schools, pre-schools and childcare: 2015 update

The aim of these guidelines is to assist staff in school and childcare settings to plan and implement appropriate risk minimisation strategies, taking into consideration the needs of the allergic child, the likely effectiveness of measures and the practicality of implementation. Although these guidelines include risk minimisation strategies for allergic reactions to insect stings or bites, latex and medication, the major focus relates to food allergy. This is due to the higher relative prevalence of food allergy in childhood (compared with other allergic triggers) and the higher likelihood of accidental exposure in these settings. Care of the allergic child in the school, pre-school or childcare settings requires accurate information obtained from parents and carers, staff training in the recognition and management of acute allergic reactions, planning for unexpected reactions (including in those not previously identified as being at risk), age appropriate education of children with severe allergies and their peers, and implementation of practical strategies to reduce the risk of accidental exposure to known allergic triggers. Strategy development also needs to take into account local or regional established legislative or procedural guidelines and the possibility that the first episode of anaphylaxis may occur outside the home. Food bans are not recommended as the primary risk minimisation strategy due to difficulties in implementation and lack of proven effectiveness.

Time trends in Australian hospital anaphylaxis admissions in 1998-1999 to 2011-2012

BACKGROUND

Studies from the United Kingdom, the United States, and Australia have reported increased childhood food allergy and anaphylaxis prevalence in the 15 years after 1990.

OBJECTIVE

We sought to examine whether childhood food allergy/anaphylaxis prevalence has increased further since 2004-2005.

METHODS

We examined hospital anaphylaxis admission rates between 2005-2006 and 2011-2012 and compared findings with those from 1998-1999 to 2004-2005.

RESULTS

Overall population food-related anaphylaxis admission rates (per 10(5) population per year) increased from 5.6 in 2005-2006 to 8.2 in 2011-2012 (a 1.5-fold increase over 7 years). The highest rates occurred in children aged 0 to 4 years (21.7 in 2005-2006 and 30.3 in 2011-2012, a 1.4-fold increase), but the greatest proportionate increase occurred in those aged 5 to 14 years (5.8-12.1/10(5) population/y, respectively, a 2.1-fold increase) compared with those aged 15 to 29 years and 30 years or older (a 1.5- and 1.3-fold increase, respectively). Not only did absolute food-related anaphylaxis admissions increase, but the modeled year-on-year rate of increase in overall food-related anaphylaxis admissions also increased over time from an additional 0.35 per 10(5) population/y in 1998-1999 (all ages) to 0.49 in 2004-2005 and 0.63 in 2011-2012 (P < .001).

CONCLUSIONS

Food-related anaphylaxis has increased further in all age groups since 2004-2005. Although the major burden falls on those aged 0 to 4 years, there is preliminary evidence for a recent acceleration in incidence rates in those aged 5 to 14 years. This contrasts with the previous decade in which the greatest proportionate increase was in those aged 0 to 4 years. These findings suggest a possible increasing burden of disease among adolescents and adults who carry the highest risk for fatal anaphylaxis.

Serum vitamin D levels in a cohort of adult and pediatric patients with eosinophilic esophagitis

BACKGROUND

Vitamin D deficiency has been associated with increased risk for severe asthma, challenge-proven food allergy, and severe atopic dermatitis. Vitamin D levels have not been reported in patients with eosinophilic esophagitis (EoE).

OBJECTIVE

To determine levels of 25-hydroxyvitamin D in a cohort of patients with EoE.

METHODS

Total serum 25-hydroxyvitamin D was measured using liquid chromatography with tandem mass spectroscopy in adults (n = 35) and children (n = 34) with EoE. Results were compared with patient demographics, EoE-specific disease parameters, markers of sensitization, and features of severity using multivariable logistic regression.

RESULTS

The median vitamin D level was 28.9 ng/mL. Patients with insufficient vitamin D (<30 ng/mL) were older (median 25.5 vs 16.2 years) and had a higher body mass index (median 25.2 vs 19.8 kg/m(2)). Peak median esophageal eosinophil counts were not significantly different for vitamin D insufficient and sufficient patient groups; however, higher vitamin D levels correlated with higher histologic eosinophil counts (R = 0.61, P = .03). Although there were no statistical differences in total IgE or levels of specific IgE between patients with vitamin D insufficiency and those with sufficiency, a positive skin prick test reaction to peanut was more common in patients who had vitamin D insufficiency (adjusted odds ratio 7.57, P = .009). Vitamin D insufficiency was not associated with surrogate markers of severity (dilation in adults or hospitalization or emergency visits in children).

CONCLUSION

In these patients with EoE, vitamin D levels were low overall (median <30 ng/mL). The only marker of sensitization associated with insufficient vitamin D in these patients with EoE was a positive skin prick test reaction to peanut.

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

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

Prevalence of immediate-type food allergy in early childhood in seoul

PURPOSE

There are scanty epidemiologic data on the prevalence of food allergy (FA) among preschool children in Asia. We performed this study to determine the prevalence and causative foods of immediate-type FA in early childhood in Korea.

METHODS

A questionnaire-based, cross-sectional study was performed between September and October 2011. Children aged 0-6 years were recruited from 301 public child care centers in Seoul. Parents were asked to complete a questionnaire on FA. Children with FA were classified into "perceived FA, ever," "immediate-type FA, ever," and "immediate-type FA, current" according to the algorithm.

RESULTS

A total of 16,749 children were included in this study. The prevalence of "perceived FA, ever," "immediate-type FA, ever," and "immediate-type FA, current" was 15.1%, 7.0%, and 3.7%, respectively. "Immediate-type FA, current" was reported by 182 (4.9%) out of 3,738 children aged ≤2 years, 262 (3.4%) of 7,648 children aged 3-4 years, and 177 (3.3%) of 5,363 children aged 5-6 years. Hen's egg (126/621) was the most frequent cause as the individual food item, followed by cow's milk (82/621) and peanut (58/621). Among the food groups, fruits (114/621), tree nuts (90/621) and crustaceans (85/621) were the most common offending foods. The three leading causes of food-induced anaphylaxis were hen's egg (22/47), cow's milk (15/47), and peanut (14/47).

CONCLUSIONS

The prevalence of immediate-type FA in early childhood is 3.7%, and is higher in younger children. The most common offending foods differed with age.

Mucosal immunology of food allergy

Food allergies are increasing in prevalence at a higher rate than can be explained by genetic factors, suggesting a role for as yet unidentified environmental factors. In this review, we summarize the state of knowledge about the healthy immune response to antigens in the diet and the basis of immune deviation that results in immunoglobulin E (IgE) sensitization and allergic reactivity to foods. The intestinal epithelium forms the interface between the external environment and the mucosal immune system, and emerging data suggest that the interaction between intestinal epithelial cells and mucosal dendritic cells is of particular importance in determining the outcome of immune responses to dietary antigens. Exposure to food allergens through non-oral routes, in particular through the skin, is increasingly recognized as a potentially important factor in the increasing rate of food allergy. There are many open questions on the role of environmental factors, such as dietary factors and microbiota, in the development of food allergy, but data suggest that both have an important modulatory effect on the mucosal immune system. Finally, we discuss recent developments in our understanding of immune mechanisms of clinical manifestations of food allergy. New experimental tools, particularly in the field of genomics and the microbiome, are likely to shed light on factors responsible for the growing clinical problem of food allergy.

Nuts 'n' guts: transport of food allergens across the intestinal epithelium

The increase in the incidence of food allergy is a growing problem for the western world. This review will focus on the findings from several macromolecular epithelial transport experiments and drug permeability studies to provide a recent comprehension of food allergen intestinal epithelial cell transport and the allergen-epithelial relationship. Specifically, this review will aim to answer whether allergens can permeate the intestinal barrier directly via intestinal epithelial cells, and whether this mode of transport affects downstream immune reactions. By improving our understanding of the interactions which take place during exposure of food allergens with the intestinal epithelium, we can begin to understand whether the epithelial barrier plays a major role in the allergic sensitization process rather than simply restricting the entry of allergens to the underlying lamina propria.

Predictive value of specific IgE for clinical peanut allergy in children: relationship with eczema, asthma, and setting (primary or secondary care)

The usefulness of peanut specific IgE levels for diagnosing peanut allergy has not been studied in primary and secondary care where most cases of suspected peanut allergy are being evaluated. We aimed to determine the relationship between peanut-specific IgE levels and clinical peanut allergy in peanut-sensitized children and how this was influenced by eczema, asthma and clinical setting (primary or secondary care). We enrolled 280 children (0-18 years) who tested positive for peanut-specific IgE (> 0.35 kU/L) requested by primary and secondary physicians. We used predefined criteria to classify participants into three groups: peanut allergy, no peanut allergy, or possible peanut allergy, based on responses to a validated questionnaire, a detailed food history, and results of oral food challenges.Fifty-two participants (18.6%) were classified as peanut allergy, 190 (67.9%) as no peanut allergy, and 38 (13.6%) as possible peanut allergy. The association between peanut-specific IgE levels and peanut allergy was significant but weak (OR 1.46 for a 10.0 kU/L increase in peanut-specific IgE, 95% CI 1.28-1.67). Eczema was the strongest risk factor for peanut allergy (aOR 3.33, 95% CI 1.07-10.35), adjusted for demographic and clinical characteristics. Asthma was not significantly related to peanut allergy (aOR 1.93, 95% CI 0.90-4.13). Peanut allergy was less likely in primary than in secondary care participants (OR 0.46, 95% CI 0.25-0.86), at all levels of peanut-specific IgE.The relationship between peanut-specific IgE and peanut allergy in children is weak, is strongly dependent on eczema, and is weaker in primary compared to secondary care. This limits the usefulness of peanut-specific IgE levels in the diagnosis of peanut allergy in children.

An unfolded variant of the major peanut allergen Ara h 2 with decreased anaphylactic potential

BACKGROUND

Peanut allergy causes severe type 1 hypersensitivity reactions and conventional immunotherapy against peanut allergy is associated with a high risk of anaphylaxis.

OBJECTIVE

Our current study reports proof of concept experiments on the safety of a stably denatured variant of the major peanut allergen Ara h 2 for immunotherapy. We determined the impact of structure loss of Ara h 2 on its IgE binding and basophil degranulation capacity, T cell reactivity as well as anaphylactic potential.

METHODS

The secondary structure of untreated and reduced/alkylated Ara h 2 variants was determined by circular dichroism spectroscopy. We addressed human patient IgE binding to Ara h 2 by ELISA and Western blot experiments. RBL-SX38 cells were used to test the degranulation induced by untreated and reduced/alkylated Ara h 2. We assessed the anaphylactic potential of Ara h 2 variants by challenge of sensitized BALB/c mice. T cell reactivity was investigated using human Ara h 2-specific T cell lines and splenocytes isolated from sensitized mice.

RESULTS

Reduction/alkylation of Ara h 2 caused a decrease in IgE binding capacity, basophil degranulation and anaphylactic potential in vivo. However, the human T cell response to reduced/alkylated and untreated Ara h 2 was comparable. Mouse splenocytes showed higher metabolic activity upon stimulation with reduced/alkylated Ara h 2 and released similar IL-4, IL-13 and IFNγ levels upon treatment with either Ara h 2 variant.

CONCLUSIONS AND CLINICAL RELEVANCE

Reduced/alkylated Ara h 2 might be a safer alternative than native Ara h 2 for immunotherapeutic treatment of peanut allergic patients.

Food allergy: an enigmatic epidemic

Food allergy is a common disease that is rapidly increasing in prevalence for reasons that remain unknown. Current research efforts are focused on understanding the immune basis of food allergy, identifying environmental factors that may contribute to its rising prevalence, and developing immunotherapeutic approaches to establish immune tolerance to foods. Technological advances such as peptide microarray and MHC class II tetramers have begun to provide a comprehensive profile of the immune response to foods. The burgeoning field of mucosal immunology has provided intriguing clues to the role of the diet and the microbiota as risk factors in the development of food allergy. The purpose of this review is to highlight significant gaps in our knowledge that need answers to stem the progression of this disorder that is reaching epidemic proportions.

Progress in understanding the epigenetic basis for immune development, immune function, and the rising incidence of allergic disease

The profile of allergic disease worldwide continues to change as the number of severe IgE-mediated allergies increases. This phenomenon is thought to reflect the outcome of combined genetic/environmental/developmental/stochastic effects on immune development, but understanding this remains a challenge. Epigenetic disruption at key immune genes during development has been proposed as a potential explanation for how environmental exposures may alter immune cell development and function. This represents an emerging area of research with the potential to yield new understanding of how disease risk is modified. Here, we examine recent developments in this field that are defining new epigenetic paradigms of allergic disease.

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.

Mediators released during human anaphylaxis

A range of mediators are generated during anaphylaxis, with redundancy of effects, multiple overlapping pathways, and involvement of several cell types. Key steps in the reaction occur at the site of initial contact, and mediators may not be detectable systemically. Furthermore, the potencies of various mediators vary enormously, and clinical effects may occur below our level of detection. We also do not know what converts (amplifies) a local reaction into systemic anaphylaxis. Murine models have identified several novel mediators that may propagate and/or regulate this process and also indicate that circulating neutrophils may play an important role in reaction amplification. Differential expression of various genes within specific intracellular signalling pathways of mediator release may further explain the varying severities of anaphylactic reactions. As our knowledge of the mechanisms of activation, key mediators, and the regulation of mediator release improves, new treatments for prevention and acute management may emerge.

Latitude, sunlight, vitamin D, and childhood food allergy/anaphylaxis

Vitamin D is widely known for its role in bone metabolism, but this sterol hormone also has important immunomodulatory properties. Vitamin D is produced by the conversion of D3 in the skin following UVB exposure, or after ingestion of D2 or D3. At the extremes of latitude, there is insufficient UVB intensity in the autumn and winter months for adequate synthesis of vitamin D to occur. Growing evidence implicates vitamin D deficiency in early life in the pathogenesis of nonskeletal disorders (e. g., type 1 diabetes and multiple sclerosis) and, more recently, atopic disorders. Several studies have reported higher rates of food allergy/anaphylaxis or proxy measures at higher absolute latitudes. Although causality remains to be determined, these studies suggest a possible role for sunlight and/or vitamin D in the pathogenesis of food allergy/anaphylaxis.

Comparison of the incidence, etiology, and management of anaphylaxis over time

BACKGROUND

Failure to promptly recognize and treat anaphylaxis can result in death. Understanding the incidence, etiology, and management is imperative. A previous pediatric study identified latex as the most common anaphylaxis allergen. We aim to describe the incidence, etiology, and management of anaphylaxis prelatex and postlatex-precaution implementation.

METHODS

Retrospective review of inpatient and emergency department (ED) records of pediatric anaphylaxis patients seen at 1 institution between 1986 and 1990 or 2002 and 2006 was performed. Patients with 2 systemic symptoms (gastrointestinal, respiratory, hypotension/syncope, oropharyngeal, altered mental status) or 1 systemic symptom plus 1 cutaneous symptom (urticaria, edema, or flushing) were included.

RESULTS

Fifty-three episodes were included from 1986 to 1990. A total of 117 episodes were included from 2002 to 2006. Approximately 80% of cases presented to the ED. From 1986 to 1990, we noted 30.5 cases per 100,000 ED visits versus 38 cases per 100,000 ED visits from 2002 to 2006. Food allergens were most common in both groups (43%). Latex accounted for only 1.9% of cases in 1986 to 1990 versus 1.7% postlatex precautions. Prehospital epinephrine use was poor. Patients in 2002 to 2006 were more likely to receive steroids, H2-blockers, epinephrine autoinjectors, and allergist referrals but less likely to receive epinephrine.

CONCLUSIONS

The etiology of pediatric anaphylaxis has not significantly changed over time but seems to differ across regions because latex was not a significant allergen at this institution in either period. The incidence of anaphylaxis has increased slightly. Anaphylaxis remains underdiagnosed and undertreated. Improved education of patients/caregivers and health care providers is needed.

Peanut oral immunotherapy: is it ready for clinical practice?

The prevalence of peanut allergy in the United States and other Westernized countries has tripled in the past 15 years, now affecting more than 1% of the population. Strict peanut avoidance is the current standard of care. In the past decade, a number of small, largely uncontrolled clinical trials have suggested that oral immunotherapy (OIT) can effectively desensitize most children with peanut allergy. Some in the allergy community now feel that OIT is ready for clinical practice. In this review, the evidence base in the medical literature is examined. Although peanut OIT shows promise, the evidence currently available on its effectiveness, risk benefit, and potential long-term consequences is insufficient to support its use in clinical practice. Appropriately designed, prospective clinical trials are urgently needed to determine whether OIT is a safe, effective form of therapy for food allergy.

Evidence of pathway-specific basophil anergy induced by peanut oral immunotherapy in peanut-allergic children

BACKGROUND

In Westernized countries, over 1% of the population is allergic to peanuts or tree nuts, which carries a risk of severe allergic reactions. Several studies support the efficacy of peanut oral immunotherapy (OIT) for reducing the clinical sensitivity of affected individuals; however, the mechanisms of this effect are still being characterized. One mechanism that may contribute is the suppression of effector cells, such as basophils. Basophil anergy has been characterized in vitro as a pathway-specific hyporesponsiveness; however, this has not been demonstrated to occur in vivo.

OBJECTIVE

To evaluate the hypothesis that basophil anergy occurs in vivo due to chronic allergen exposure in the setting of a clinical oral immunotherapy trial.

METHODS

Samples of peripheral blood were obtained from subjects during a placebo-controlled clinical trial of peanut OIT. Basophil reactivity to in vitro stimulation with peanut allergen and controls was assessed by the upregulation of activation markers, CD63 and CD203c, measured by flow cytometry.

RESULTS

The upregulation of CD63 following stimulation of the IgE receptor, either specifically with peanut allergen or non-specifically with anti-IgE antibody, was strongly suppressed by active OIT. However, OIT did not significantly suppress this response in basophils stimulated by the distinct fMLP receptor pathway. In the subset of subjects with egg sensitization, active peanut OIT also suppressed CD63 upregulation in response to stimulation with egg allergen. Allergen OIT also suppressed the upregulation of CD203c including in response to stimulation with IL-3 alone.

CONCLUSION

Peanut OIT induces a hyporesponsive state in basophils that is consistent with pathway-specific anergy previously described in vitro. This suggests the hypothesis that effector cell anergy could contribute to clinical desensitization.

The role of nuts in the optimal diet: time for a critical appraisal?

During the last decades, nuts have attracted the attention of researchers for their potential benefits in cardiovascular prevention. We discuss here some aspects of the assumed beneficial effects of nuts, weighing them against potential harm. Epidemiological observations and controlled intervention trials consistently suggest that nuts consumption is associated with improved serum lipid profile, thus helping decrease cardiovascular risk. Being nuts an energy dense food, their impact on energy balance and body weight should be considered. In particular, the claim that adding nuts to the habitual diet, thus increasing calorie intake, does not cause body fat accumulation still needs evidence and biological plausibility. The potential risk associated with the relatively frequent occurrence of allergic reactions following the consumption of nuts is also discussed.

Peanut allergy diagnoses among children residing in Olmsted County, Minnesota

BACKGROUND

Peanut allergy is a major health concern, particularly in developed countries. Research indicates that as many as 2% of children are allergic to peanuts, which represents a 3-fold increase in diagnoses over the past 2 decades.

OBJECTIVE

This population-based descriptive study used the Rochester Epidemiology Project to estimate the prevalence in 2007 and annual incidence rates of peanut allergy diagnoses from 1999 to 2007 among children residing in Olmsted County, Minnesota.

METHODS

Residents of Olmsted County from January 1, 1999, through December 31, 2007, who received medical care at a Rochester Epidemiology Project facility and provided research authorization were eligible for the study. A medical chart review of 547 potential diagnoses resulted in 244 prevalent and 170 incident cases. Annual rates, crude and adjusted for age and sex, were standardized with the use of the indirect method to the Olmsted County population data in 1999. Incidence rate ratios were estimated with Poisson regression.

RESULTS

The prevalence in 2007 was 0.65%. Female children were less likely to be diagnosed than male children (incidence rate ratio = 0.18; 95% CI, 0.07-0.48). Children aged birth to 2 years were significantly more likely to be diagnosed than older children aged 3-17 years (incidence rate ratio = 0.001; 95% CI, 0.0004-0.004). A significant 3-fold increasing trend was observed in diagnoses over time from 2.05 cases per 10,000 children in 1999 to 6.88 cases per 10,000 in 2007.

CONCLUSIONS

Peanut allergies are an increasing concern in Olmsted County, Minnesota, as indicated by a 3-fold increase in diagnoses from 2.05 per 10,000 children in 1999 to 6.88 per 10,000 children in 2007.

Neonatal vitamin D status and childhood peanut allergy: a pilot study

BACKGROUND

Although a number of factors have been proposed to explain the increase in food allergy during the last decade, the possibility that vitamin D status may play a pathogenic role has received recent attention.

OBJECTIVE

To determine whether lower levels of neonatal 25-hydroxyvitamin D (25[OH]D) would be observed in children with peanut allergy compared with in population controls.

METHODS

The concentration of 25(OH)D was measured from neonatal dried blood samples by liquid chromatography tandem mass spectrometry. Levels were compared between children with IgE-mediated peanut allergy younger than 72 months assessed during 2008-2011 in a specialist referral clinic in the Australian Capital Territory and population births matched by sex, birth date, and birth location. Odds ratios were calculated for the matched pairs across quintiles of 25(OH)D.

RESULTS

Neonatal 25(OH)D levels ranged from 8 to 180 nmol/L (median, 66 nmol/L; interquartile range, 46-93 nmol/L); only 4 children (3%) had levels less than 25 nmol/L, and 24 (20.9%) had levels greater than 100 nmol/L. No significant association was found between socioeconomic or clinical factors and 25(OH)D levels. Compared with the reference group (50-74.9 nmol/L), levels of 75 to 99.9 nmol/L were associated with lower risk of peanut allergy (P = .02). No further reduction was found at levels of 100 nmol/L or higher, and the risk of peanut allergy at levels less than 50 nmol/L was not significantly different from the reference group.

CONCLUSION

The relationship between neonatal 25(OH)D level and childhood peanut allergy was nonlinear, with slightly higher levels (75-99.9 nmol/L) associated with lower risk than those in the reference group (50-74.9 nmol/L). Vitamin D status may be one of many potential factors contributing to childhood peanut allergy pathogenesis.