Adrenaline autoinjectors and schoolchildren: a community based study. (1/24)

Sixty schoolchildren prescribed adrenaline autoinjectors were identified by surveying schools in Hounslow, London; the 25 families who consented were interviewed. There was inconsistency in prescription and use of autoinjectors with poor training, absence of written instructions, and lack of follow up. It is recommended that national guidelines should be developed.  (+info)

Polymorphism in the STAT6 gene encodes risk for nut allergy. (2/24)

Nut allergy is an important and potentially life threatening food allergy with a prevalence of one in 150 children in the UK population. STAT6 (signal transducer and activator of transcription) is an important molecule in the induction and regulation of an allergic response, which maps to chromosome 12q in a region previously linked with total serum IgE concentration and atopy in different populations. We have examined the frequency of a single nucleotide polymorphism (SNP) in the 3'UTR region of STAT6 gene in 71 UK Caucasoid patients diagnosed with nut allergy and 45 atopic patients without nut allergy using PCR-RFLP and compared these with 184 UK healthy controls. The STAT6 G allele frequency was significantly increased in nut allergy patients compared with blood donor controls (P < 0.0001, OR = 2.9, 95% CI: 1.7-4.9), which was under a recessive model (GG vs GA+AA, P = 0.0001, OR = 3.2, 95% CI: 1.7-5.8) but not in atopic patients without nut allergy. The G allele was most frequent in the severe cases and GG homozygosity was associated with the increased risk of severe reaction (OR = 3.9, 95% CI: 1.9-8.3). We conclude that STAT6 3'UTR polymorphism is associated with susceptibility and severity in nut allergic patients in our population.  (+info)

Antiulcer drugs promote oral sensitization and hypersensitivity to hazelnut allergens in BALB/c mice and humans. (3/24)

BACKGROUND: Hazelnut allergy can be a consequence of sensitization to cross-reactive pollen, especially from the Fagales family. However, severe allergic reactions after ingestion of hazelnuts without associated pollen allergy have been reported. In these cases, oral sensitization by hazelnut ingestion is plausible. OBJECTIVE: We have reported that antiulcer drugs promote oral sensitization to digestion-labile food allergens. Because hazelnut proteins were sensitive to gastric digestion in our in vitro assay, we aimed to analyze the effect of antiulcer treatment on oral sensitization to hazelnut proteins. DESIGN: BALB/c mice were fed hazelnut extract with or without antiulcer drugs. In parallel, gastroenterologic patients (n = 153) were screened during antiulcer treatment for specific immunoglobulin (Ig) E to hazelnut and inhalative allergens in vitro and in vivo. RESULTS: Mice fed hazelnut extract in combination with antiulcer drugs formed anaphylactogenic IgG1 toward hazelnut and developed type I skin reactivity to hazelnut extract. In the human study population, 5 of 153 (3.3%) patients developed hazelnut-specific IgE, 4 of 5 developed specific skin reactivity, 3 of 5 had a positive result to oral provocation, and 2 of 5 manifested a food allergy to hazelnut after a 3-mo course of antiulcer treatment. Immunoblot testing with recombinant allergens showed that hazelnut, but not Fagales pollen, was the genuine elicitor in mice and humans. CONCLUSION: Our experimental and epidemiologic data suggest that the intake of antiulcer drugs may lead to the induction of immediate-type food hypersensitivity toward hazelnut.  (+info)

Cashew nut allergy is associated with a high risk of anaphylaxis. (4/24)

Cashew allergy is an evolving clinical problem. A retrospective chart review of 213 children with peanut or tree nut allergy was undertaken over a 42 month period. Anaphylaxis to cashew nut was more common than to peanut (74.1% v 30.5%). Children with cashew allergy are at risk of anaphylaxis.  (+info)

Differences in allergenic potential of food extracts following oral exposure in mice reflect differences in digestibility: potential approaches to safety assessment. (5/24)

An animal model for food allergy is needed to assess genetically modified food crops for potential allergenicity. The ideal model must produce allergic antibody (IgE) to proteins differentially according to known allergenicity before being used to accurately identify potential allergens among novel proteins. The oral route is the most relevant for exposure to food antigens, and a protein's stability to digestion is a current risk assessment tool based on this natural route. However, normal laboratory animals do not mount allergic responses to proteins administered orally due to oral tolerance, an immunologic mechanism which specifically suppresses IgE. To circumvent oral tolerance and evoke differential IgE responses to a panel of allergenic and nonallergenic food extracts, female C3H/HeJ mice were exposed subcutaneously or orally with cholera toxin as an adjuvant. All foods elicited IgE by the subcutaneous route. Oral exposure, however, resulted in IgE to allergens (peanut, Brazil nut, and egg white) but not to nonallergens (spinach and turkey), provided that the dose and exposures were limited. Additionally, in vitro digestibility assays demonstrated the presence of digestion-stable proteins in the allergenic food extracts but not in the nonallergenic foods. Our results suggest that the subcutaneous route is inadequate to distinguish allergens from nonallergens, but oral exposure under the appropriate experimental conditions will result in differential allergic responses in accordance with known allergenicity. Moreover, those foods containing digestion-resistant proteins provoke allergic responses in this model, supporting the current use of pepsin resistance in the decision tree for potential allergenicity assessment.  (+info)

Fixed food eruption caused by cashew nut. (6/24)


Tree nut and peanut consumption in relation to chronic and metabolic diseases including allergy. (7/24)

The New and Emerging Research session highlighted the emerging understanding of both the positive and negative effects of nuts consumption on health. The limited nature of both experimental and epidemiological evidence for positive relationship(s) between nut intake and health were noted. Study inconsistency and limitations, particularly survey methodology, were explored. Recent results from epidemiologic studies indicating a potential negative association between nut and seed intake and cancer risk were reviewed. The ability of walnuts to reduce endothelin suggests an interesting biochemical mechanism of nut action that may affect other endothelin-associated diseases, which should be further explored. The effects of nuts and their constituents on a nuclear receptor screen (PPARalpha, beta/delta, gamma, LXRalpha, beta, RXRalpha, beta, gamma, PXR, and FXR) have been explored. Nut allergenicity and approaches necessary to minimize this effect were also described. In contrast to the positive effects, nut allergies present tree nut-allergic consumers with health challenges. The Food Allergy and Anaphylaxis Network stressed the importance of ensuring that consumers with food allergies have legible, accurate food labels. The Food Allergen Labeling and Consumer Protection Act has engendered precautionary, worst-case allergen scenario labeling statements with unknown benefits to consumer health. Issues of cross-contamination due to shared equipment and shared facilities highlighted the need to rely on allergen control programs that use ELISA technology and have increased understanding of nut allergens. Ultimately, to maximize the positive benefits of nuts, the consumer must be provided with all the information required to make an informed choice.  (+info)

Priority areas for research on the intake, composition, and health effects of tree nuts and peanuts. (8/24)

This article summarizes the main conclusions drawn from a conference on the health effects of nut consumption and identifies priority areas for future research. Individuals with higher intakes of nuts generally have higher intakes of many beneficial dietary constituents. More information is needed on nut composition, the bioavailability of nutrients, and other bioactive constituents. Better methods are needed to assess usual nut intake, including biomarkers, and the types, physical form, and amounts of nuts that are consumed. The feasibility of including nuts and seeds as a separate food group in the Dietary Guidelines should be tested, as should ways to increase nut intake. A moderate intake of nuts can be included in a weight loss regimen and further information is needed on whether nuts improve satiety as well as adherence to and efficacy of diets designed for weight reduction. There is substantial evidence that nut consumption reduces risk of cardiovascular disease. Future research should investigate their benefits for prevention of congestive heart failure, including clinical studies in patients with this condition, to evaluate the effects of nuts on markers of heart disease risk. Higher nut consumption is associated with lower risk of diabetes and associated cardiovascular disease. More remains to be learned about the effects of nuts on postprandial glycemic and insulin response, glycemic control, and improvement of disease risk factors in subjects with prediabetes and diabetes. Information is needed on nut-induced allergic reactions, including their prevalence and consequences, causes of sensitization, biomarkers of severe reactions, and cross-reactivity to different types of nuts.  (+info)