Aspergillus section Flavi and aflatoxins in dried figs and nuts in Algeria.
The presence of Aspergillus section Flavi and aflatoxin (AF) contamination was investigated in 112 samples of peanuts, almonds and dried figs collected in Algeria. The occurrence of aflatoxin B1 (AFB1), B2 (AFB2), G1 (AFG1) and G2 (AFG2) in different commodities has been determined with a sensitive method based on high performance liquid chromatography (HPLC) coupled with fluorescence detection with post-column photochemical derivatisation. Analytical results indicated that 28 samples of peanuts, 16 samples of almonds and 26 samples of dried figs contained detectable levels of AFs. A total of 69 samples (61.6%) were contaminated with AFB1 ranging from the limit of quantification to 174 µg kg-1. AFB2 was found in 12 samples (10.7%) and varied from 0.18 to 193 µg kg-1. Seven samples revealed AF concentrations lower than the limit of quantification. Eleven peanut and fourteen dried fig samples exceeded the European maximum limits for AFB1.
Advances in the Approach to the Patient with Food Allergy.
Advances in food allergy diagnosis, management, prevention and therapeutic interventions have been significant over the past two decades. Evidence based national and international guidelines have streamlined food allergy diagnosis and management, while paradigm shifting work in primary prevention of peanut allergy has resulted in significant modifications in the approach to early food introduction in infants and toddlers. Innovative investigation of food allergy epidemiology, systems biology, impact, and management has provided important insights. While active therapeutic approaches to food allergy presently remain experimental, progress toward licensed therapies has been substantial. Mechanistic understanding of the immunologic processes underlying food allergy and immunotherapy will inform the future design of therapeutic approaches targeting the food allergic response. Global strategies to mitigate the substantial medical, economic, and psychosocial burden of food allergy in affected individuals and families will require engagement of stakeholders across multiple sectors in research, healthcare, public health, government, educational institutions and industry. However, the relationship between the well-informed allergy care provider and the patient and family remains fundamental for optimizing the care of the patient with food allergy.
The effect of oral immunotherapy treatment in severe IgE mediated milk, peanut, and egg allergy in adults.
INTRODUCTION: The standard care of severe food allergy in both adults and children means avoidance of allergens. In recent years promising results of oral immunotherapy (OIT) have been reported in children. In adults, information on OIT in severe food allergy is very limited. OBJECTIVE: We aimed to study if OIT is possible in adults. METHODS: We report OIT results in 10 adult patients with milk OIT, nine adult patients with peanut OIT, and four adult patients with egg OIT. The allergy was confirmed with allergen specific IgE tests and oral food challenges (open in milk allergy and double-blind in peanut and egg allergy). The OIT was performed as open. RESULTS: The median dose of protein that led to discontinuation of allergen challenge because of symptoms was 7.5 mg in milk allergy, 25 mg in peanut allergy, and 15 mg in egg allergy. The median period of OIT was 515 days. Currently on OIT are 6/10 milk allergic patients, 4/9 peanut allergic patients and 3/4 egg allergic patients. The median dose of milk protein increased by 60-fold during OIT compared to the allergen challenge dose. In peanut OIT the median dose increased by eightfold and in egg allergy the dose increased with OIT by 35-fold. Local itching was the most common side effect of OIT (73.9% of the patients), four patients reported having used epinephrine autoinjector and three patients having needed emergency room treatment. CONCLUSIONS AND CLINICAL RELEVANCE: OIT can be given in adult patients with severe milk, peanut, or egg allergy only in selected cases. OIT leads into desensitization but it is not clear whether persistent tolerance can be achieved. Mild adverse events during OIT are common.
Preventing Peanut Allergy.
The rising prevalence of food allergy and specifically peanut allergy has had significant implications for affected patients, families, and society. The current standard of care remains strict avoidance and the use of emergency medications for accidental ingestions. There is recent evidence-based information to suggest that one approach to preventing peanut allergy lies in early introduction of peanut. This represents a paradigm shift from previous recommendations and has led to updated guidelines in the United States, Europe, and Australasia on the introduction of potentially allergenic foods in the infant diet. This new approach to prevention has some practical obstacles and challenges associated with its implementation. There is also growing interest in the role of maintaining a healthy skin barrier in prevention of sensitization and food allergy. Other approaches, including pro- and prebiotics, prenatal maternal dietary avoidance, breastfeeding, and the use of specific formulas, have not shown reproducibly favorable results. As children with peanut allergy are unlikely to outgrow their food allergy, early oral immunotherapy in those with established peanut allergy is being investigated with the hopes of altering the natural history of an otherwise lifelong disease.
" To Screen or not to Screen": Comparing the Health and Economic Benefits of Early Peanut Introduction Strategies in Five Countries.
BACKGROUND: Early peanut introduction (EPI) in the first year of life is associated with reduced risk of developing peanut allergy in children with either severe eczema and/or egg allergy. However, EPI recommendations differ among countries with formal guidelines. METHODS: Using simulation and Markov modeling over a 20-year horizon to attempt to explore optimal EPI strategies applied to the US population, we compared high-risk infant specific IgE peanut screening (US/Canadian) with the Australiasian Society for Clinical Immunology and Allergy (Australia/New Zealand) (ASCIA) and the United Kingdom Department of Health (UKDOH) published EPI approaches. RESULTS: Screening peanut skin testing of all children with early onset eczema and/or egg allergy before in-office peanut introduction was dominated by a no-screen approach, in terms of number of cases of peanut allergy prevented, QALY's, and healthcare costs, though screening resulted in a slightly lower rate of allergic reactions to peanut per-patient in high-risk children. Considering costs of peanut allergy in high-risk children, the per-patient cost of early introduction without screening over the model horizon was $6,556.69 (95%CI, $6,512.76-$6,600.62), compared with a cost of $7,576.32 (95%CI, $7,531.38-$7,621.26) for skin test screening prior to introduction. From a US societal perspective, screening prior to introduction cost $654,115,322 and resulted in 3,208 additional peanut allergy diagnoses. Both screening and non-screening approaches dominated deliberately delayed peanut introduction. CONCLUSIONS: A no-screening approach for EPI has superior health and economic benefits in terms of number of peanut allergy cases prevented, QALY's, and total health care costs compared to screening and in-office peanut introduction.
Changes in immunoreactivity of allergen-reduced peanuts due to post-enzyme treatment roasting.
The objective of this study was to evaluate the effect of enzyme treatment and post-enzyme treatment roasting on allergenicity of raw peanut kernels. Raw peanuts were treated by single- and two-enzyme treatments, respectively. Enzyme-treated raw peanuts were dry roasted. Reductions of four major allergens (Ara h 1, 2, 3, and 6) and in vitro allergenicity of peanuts were evaluated. Quantitative measurements show that enzyme treatment of raw peanuts reduced Ara h 1, 2, 3 and 6 in raw peanuts by 99-100%, 95-99%, 35-46% and 85-88%, respectively. Roasting of enzyme-treated peanuts significantly reduced the total soluble protein (P < 0.05), Ara h 3 and 6 (P < 0.0001), slightly increased Ara h 1 in the extracts (P < 0.05), but did not significantly affect Ara h 2. Immunoblot shows that the IgE-bindings of both soluble and insoluble proteins of enzyme-treated peanuts were slightly enhanced by roasting but still tremendously lower than that of untreated peanuts.
Food Allergy.
PURPOSE OF REVIEW: The goal of this review is to present an updated summary of the natural history of major childhood and adult food allergies and report recent advances in potential treatments for food allergy. RECENT FINDINGS: The most common childhood food allergies are typically outgrown by adolescence or adulthood. However, peanut/tree nut allergies appear to more commonly persist into adulthood. Adults can develop new IgE-mediated food allergies; the most common is oral allergy syndrome. There are multiple different approaches being tried as possible treatments for food allergy. The prevalence of food allergy appears to be increasing but the varied approaches to treatment are being actively pursued such that an approved modality may not be too far in the future.
Clinical presentation of cashew nut allergy in a paediatric cohort attending an allergy clinic in the West of Ireland.
BACKGROUND: Cashew nut (CN) allergy appears to be increasing. Reactions are variable and may include anaphylaxis. AIM: To describe the clinical features of CN allergy in a group of children attending an allergy clinic with suspected peanut allergy and confirmed sensitisation to CN. METHODS: Patients were identified retrospectively by reviewing the Immunology Database at University Hospital Galway over a 5-year period, Oct. 2010 to Sept. 2015. Patients confirmed sensitised to CN (specific IgE > 0.35 kUa/L, ImmunoCAP Assay) were selected and contacted. RESULTS: Over the 5-year period, 115 children were identified; 102/115 were individually contacted. Of the 102 children, 55 had a history of prior CN exposure with confirmed clinical reaction, 43 had no prior CN exposure, and 4 were sensitised and tolerating CN. For those with clinical CN allergy (N = 55), 30 (55%) were male and median age of onset was 2 years (lower quartile 1.5, upper quartile 4.8). Severity of reaction was graded as mild for 13 children, moderate in 13 additional children, and severe in 29 children. Median CN serum IgE level was 3.2 kUa/L (range 0.36 to > 100) in the clinical reaction group, 2.91 kUa/L (range 0.36 to > 100) in the sensitised group, and 3.4 kUa/L (range 0.94 to 5.21) in those tolerating CN. IgE values were not significantly different between those with mild, moderate, or severe reaction to CN (p = 0.346). CONCLUSION: Children are ingesting CN at a young age with more than half of allergic reactions reportedly severe in nature. The specific CN IgE value was not helpful in predicting severity of reactions.
Microbead-based simultaneous fluorometric detection of three nut allergens.
A microbead-based method is developed for the detection of three nut allergens that can occur in food. The bead array constitutes of a suspension of spectrally distinct fluorescent polystyrene microbeads and has been applied for the simultaneous detection of three main and serious allergens (hazelnut, peanut and walnut). The method is based on the simultaneous identification of specific DNA sequences after PCR. The PCR products are biotinylated and hybridized to nut-specific oligonucleotide probes attached to the microbeads. The hybrids are finally detected by a streptavidin-phycoerythrin conjugate and flow cytometric analysis. As low as 0.01% content of the three nuts in processed food (cookies) can be detected by this method. Graphical abstract Schematic of a method for simultaneous fluorometric detection of three nut allergens in processed food (cookies) based on the use of fluorescent microbeads and flow cytometric analysis. B: Biotin; SA-PE: Streptavidin conjugated to phycoerythrin.
Application of Multiantigen Profiling To Detect Pecan.
A problem often encountered in the detection and identification of undeclared tree nut food allergens is the lack of analytical methods. This problem is accentuated by the current trend, whereby the primary methods used to detect food allergens are antibody-based enzyme-linked immunosorbent assays (ELISAs) and the development of analyte-specific antibodies takes months. The recently developed xMAP food allergen detection assay (xMAP FADA) has the ability to generate multiantigen profiles with tree nuts, thereby providing a potential solution to this problem. The xMAP FADA includes 22 antibodies targeting peanut, soy, and nine tree nuts. The high number of antibodies to a diverse group of tree nuts and legumes and the propensity of tree nuts to cross-react have enabled the development of multiantigen profiling, whereby an analyte reacts with the various antibodies to generate a profile. Recently, a question arose regarding the possible presence of pecan dust at a manufacturer of pecan products that also stored fresh produce. The lack of suitable pecan ELISAs created an analytical challenge that was resolved using multiantigen profiling with the xMAP FADA. Pecan was detected on swab samples by using multiantigen profiling and confirmed by DNA analysis. The use of multiantigen profiling provided an analytical capability beyond what was possible with an analyte-specific analytical method.