Milk allergy most burdensome in multi-food allergic children.

BACKGROUND: Food allergy is a substantial health burden, which disproportionately affects children. Among children with food allergy, as many as 70% have multiple food allergies. Whereas the overall burden of food allergy on quality of life has been described, little is known about the burden of individual allergens. We aimed to examine the perception of burden among families with multiple food-allergic children. METHODS: Parents of children with 1 + children with multiple food allergies including milk responded to online questions, including both open-ended and closed-ended questions on food allergy-related burdens of time, financial costs, social restrictions, and emotional demands. RESULTS: Overall, 64 children (69.8% boys) of whom (73.0%) most were aged 10 and younger were included. Most had been diagnosed with food allergy in infancy and by a (pediatric) allergist. Other common allergies included peanut (65.6%), tree nuts (57.8%), egg (76.6%), and sesame (31.3%). Quantitatively, milk allergy was reported as carrying the most burden, including most socially limiting (81.5%), requiring the most planning (75.9%), causing the most anxiety (68.5%), most challenging to find "safe" or allergy-friendly foods (72.2%), and costly (81.5%). Qualitatively, we identified five themes that captured burdens associated with costs, marketing of milk products to children, risk of cross-contamination, ubiquity of milk/dairy and public confusion with lactose intolerance, and an unwillingness of others to accommodate the allergy. CONCLUSION: Parents whose children have multiple food allergies, including milk, report milk as the allergy associated with the greatest time, financial, social, and emotional burdens.

Updated population minimal eliciting dose distributions for use in risk assessment of 14 priority food allergens.

Food allergy and allergen management are important global public health issues. In 2011, the first iteration of our allergen threshold database (ATDB) was established based on individual NOAELs and LOAELs from oral food challenge in roughly 1750 allergic individuals. Population minimal eliciting dose (EDp) distributions based on this dataset were published for 11 allergenic foods in 2014. Systematic data collection has continued (2011-2018) and the dataset now contains over 3400 data points. The current study provides new and updated EDp values for 14 allergenic foods and incorporates a newly developed Stacked Model Averaging statistical method for interval-censored data. ED01 and ED05 values, the doses at which 1%, and respectively 5%, of the respective allergic population would be predicted to experience any objective allergic reaction were determined. The 14 allergenic foods were cashew, celery, egg, fish, hazelnut, lupine, milk, mustard, peanut, sesame, shrimp (for crustacean shellfish), soy, walnut, and wheat. Updated ED01 estimates ranged between 0.03 mg for walnut protein and 26.2 mg for shrimp protein. ED05 estimates ranged between 0.4 mg for mustard protein and 280 mg for shrimp protein. The ED01 and ED05 values presented here are valuable in the risk assessment and subsequent risk management of allergenic foods.

Evaluation of the healthcare resource use and the related financial costs of managing peanut allergy in the United Kingdom.

Aims: We aimed to estimate the resource use and associated costs for patients with peanut allergy (PA) compared to matched controls. Methods: This was a retrospective cohort study using data from the UK Clinical Practice Research Datalink and Hospital Episode Statistics. PA patients were matched to two control cohorts: the first (simple-matched) were matched 1:1 on year of birth, general practice, gender and registration year. The second (atopy-matched) were matched on the same characteristics plus presence/absence of an atopic condition. Prescriptions and primary and secondary care contacts were compared between cases and controls. Results: 15,483 peanut-allergic patients were identified: 13,609 (87.9%) were simple-matched and 9,320 (60.2%) atopy-matched. The total per person annual incremental health-care costs associated with PA were £253 (atopy-matched) and £333 (simple-matched). For those with PA and a prior anaphylaxis incremental costs were £662, for those prescribed an epinephrine autoinjector incremental costs were £392. Extrapolated to the U.K. population, total excess costs of PA were between £33 and 44 million in 2015. Conclusions: Patients with PA had increased health-care contacts and consequently increased associated costs compared to controls. Observation bias should be considered in interpretation, but this study suggests that PA presents significant burden to health-care systems.

Estimation of Health and Economic Benefits of Commercial Peanut Immunotherapy Products: A Cost-effectiveness Analysis.

Importance: Commercial epicutaneous peanut immunotherapy (EPIT) and peanut oral immunotherapy (POIT) may offer significant quality-of-life improvements for patients with peanut allergy, but the cost-effectiveness of commercial peanut immunotherapies is uncharacterized. Objective: To evaluate critical inputs associated with the cost-effectiveness of EPIT and POIT from a societal perspective. Design, Setting, and Participants: Economic evaluation in which microsimulations with Markov modeling were performed evaluating virtual children aged 4 years over an 80-year time horizon. The base-case costs included a caregiver-reported willingness to pay of $3839 annually for safe and effective food allergy treatment. Estimates of predictive biomarkers or oral challenges were incorporated after the first year of therapy with additional analyses of immunotherapy risk reduction of anaphylaxis and probability of sustained unresponsiveness (SU) to peanut after 4 years. Exposures: Children received EPIT, POIT, or no immunotherapy treatment (n = 10 000 per treatment strategy). Main Outcomes and Measures: Rates of therapy-associated adverse reactions and quality-of-life improvements associated with changes in eliciting or tolerated peanut doses were modeled along with quality-adjusted life-years (QALYs), anaphylaxis, therapy-associated anaphylaxis, and fatalities. Results: In the base-case analysis without SU to peanut, the EPIT strategy cost less than POIT (mean [SD] cost, $154 662 [$46 716] vs $163 524 [$56 800]) and had fewer total episodes of anaphylaxis (mean [SD], 1.33 [1.55] vs 3.83 [5.02] episodes) and fewer episodes of therapy-associated anaphylaxis (mean [SD], 0.62 [1.30] vs 3.10 [4.94] episodes) but had lower QALY accumulation (mean [SD], 26.932 [2.241] vs 26.945 [2.320] QALYs). The incremental cost-effectiveness ratio was $216 061 for EPIT and $255 431 for POIT. Models were sensitive to therapy cost, SU rates, health state utility, and risk reduction of anaphylaxis. With health state utility sensitivity analyses, the ceiling value-based cost (willingness-to-pay threshold $100 000/QALY) was between $1568 and $6568 for EPIT and between $1235 and $5235 for POIT. If high rates of SU to peanut can be achieved in longer-term models, EPIT and POIT could produce savings in terms of both cost and QALY. Conclusions and Relevance: In this simulated analysis, findings showed that EPIT and POIT may be cost-effective under some assumptions. Further research is needed to understand the degree of health state utility improvement associated with each therapy, degree of protection against anaphylaxis, and rates of SU.

Providing cost-effective care for food allergy.

OBJECTIVE: To review the cost-effectiveness of food allergy management strategies. DATA SOURCES AND STUDY SELECTIONS: A narrative review and synthesis of literature identified using a PubMed search of relevant articles describing cost-effectiveness evaluations of food allergy management. RESULTS: Screening at-risk infants for peanut allergy carries risk of overdiagnosis and is not cost-effective. Evidence suggests that cost-effective care could be better optimized by minimizing delay in oral food challenges for eligible patients, clarifying the role of precautionary allergen labeling, incorporating patient-preference sensitive care in activation of emergency medical services for resolved allergic reactions, and considering value-based pricing and school-supply models for epinephrine. Finally, the annual value-based cost (willingness to pay [WTP] $100,000/quality-adjusted life years [QALY]) of peanut immunotherapy has been estimated to be between $1568 and $6568 for epicutaneous immunotherapy (EPIT) and between $1235 and $5235 for probiotic with peanut oil immunotherapy (POIT), with each therapy showing more favorable cost-effectiveness with greater improvements in health utility, particularly if sustained unresponsiveness can be achieved. CONCLUSION: Many aspects of food allergy management are not cost-effective, and recent evaluations suggest a greater role for incorporating patient and family preferences into guideline-based and traditionally reflexive management decisions. Caregiver understanding of food allergy screening tradeoffs is critical, given that screening children before allergen exposure has significant costs and results in overdiagnosis, especially when oral food challenges are omitted from diagnostic algorithms. Cost-effectiveness analysis can help to identify important decision levers in patient management across a wide range of topics. Further research is needed to better understand health state utilities of specific patient populations.

Allergenicity assessment on thermally processed peanut influenced by extraction and assessment methods.

The effect of processing on allergenicity of peanut, a major allergic food remains uncertainty. To discover the influence of thermal processing, extraction and assessment methods on potential allergenicity, protein was extracted by three methods or digested in the form of defatted peanut powder (DPP). The components of extracted allergens were analyzed using electrophoresis and mass spectrometry; the advanced structures (the secondary structure and the tertiary structure) were characterized through spectroscopies; the potential allergenicities were assessed by enzyme linked immunosorbent assay (ELISA), Biolayer interferometry (BLI) and KU812 cell degranulation assay. Results demonstrated that extraction influenced the allergenicity assessment significantly, and the assessment method was also important. The potential allergenicity of protein changed after processing, it increased after roasting, while decreased after boiling. Additionally, digested DPP combined with basophilic granulocyte degranulation model might be a good allergenicity assessment method.

An economic evaluation of immediate vs non-immediate activation of emergency medical services after epinephrine use for peanut-induced anaphylaxis.

BACKGROUND: Layperson food allergy management plans commonly stipulate that if epinephrine is used to immediately call 911 and seek care in the nearest medical facility for observation. OBJECTIVE: To evaluate the cost-effectiveness of this strategy, vs a watchful waiting approach before activating emergency medical services (EMS). METHODS: We performed a cost-effectiveness analysis using Markov modeling simulated over a 20-year horizon comparing activating EMS immediately after epinephrine use for allergic reactions to peanut vs a "wait and see" approach in which EMS was only activated if symptoms of the reaction did not promptly resolve after treatment. The base-case model assumed a 10-fold increased fatality risk with delayed EMS activation. RESULTS: The fatality risk associated with early EMS use was minimal, with a per-patient fatality rate over a 20-year horizon of 1.2 × 10-6, vs 1.9 × 10-6 for a wait and see approach. The incremental cost per life-year saved was $142,943,447 for early EMS vs wait and see, with the cost per death prevented reaching $1,349,335,651 as the simulation concluded. Cost of early EMS activation rose to $321,625,534 per life-year saved ($3,035,454,848 per death prevented) if a 5-fold increase in fatality risk was assumed, and was $12,997,173 per life-year saved ($122,689,936 per death prevented) if a 100-fold increase in fatality risk was assumed. CONCLUSION: Medical observation of a treated and promptly resolved peanut allergic reaction has minimal benefit and excessive costs. Immediately activating EMS after using epinephrine for a peanut allergic reaction in this context is not cost-effective.

The Health and Economic Outcomes of Peanut Allergy Management Practices.

BACKGROUND: Peanut allergy is managed with strict avoidance, epinephrine carriage, and promptly treating reactions. OBJECTIVE: The objective of this study was to assess the health and economic benefits of pre-emptively injecting epinephrine for peanut ingestion in the absence of any symptoms, and to avoid products with peanut precautionary allergen labeling (PAL). METHODS: We used Markov modeling and simulations, assuming a base-case 10-fold fatality risk increase for less conservative management, with sensitivity analysis investigating 100- to 1000-fold increased fatality risk, incorporating risks of accidental exposures, reactions, fatality, and family costs of food allergy. Low-dose threshold challenges were used to exclude subjects highly reactive to PAL items. RESULTS: Based on these assumptions, small reductions in per-patient fatality risk resulted from pre-emptive epinephrine injection without symptoms present (<1 × 10-4 fewer per-patient fatalities), with incremental costs of $1193 per patient, $11,681,501/life year saved, and $110,270,820/death prevented versus waiting for symptoms before use, but this was not cost-effective even assuming 1000-fold risk ($107, 971/quality of life adjusted year) or quality of life (QoL). There were small reductions in per-patient fatality risk (<1 × 10-4 fewer per-patient fatalities) for PAL avoidance versus universal PAL consumption, with incremental costs of $3342 per patient, $19,325,994/life year saved, and $182,434,277/death prevented versus allowing PAL consumption. PAL avoidance was not cost-effective when assuming 1000-fold risk or considering QoL. Incorporating a single, supervised low-dose challenge of 1.5 mg of peanut protein to exclude children reactive to PAL consumption was cost-effective. CONCLUSIONS: Commonly recommended practices of pre-emptive epinephrine injection in the absence of symptoms, or universal avoidance of PAL, were not cost-effective when compared with administering epinephrine on symptom development or allowing PAL consumption.

Environmental exposure to peanut and the risk of an allergic reaction.

OBJECTIVE: To review the evidence of the risk of environmental exposure to peanut to a peanut allergic individual. DATA SOURCES AND STUDY SELECTION: A narrative review was performed using a PubMed search of relevant articles involving peanut environmental distribution, environmental peanut abatement, and public policy regarding peanut restriction. RESULTS: Data from 4 studies have shown that peanut butter vapors and smeared peanut butter on skin do not cause systemic reactions, that peanut can be abated from hands and surfaces using appropriate cleaning agents, and that shelled peanut dust does not become airborne. Studies have recently confirmed dose of 1.5 mg of peanut protein would be generally tolerated by approximately 95% of the peanut-allergic population based on objective symptoms in challenge-based studies, affirming earlier research. Restrictive policies that focus on bans (or restricted presence in certain areas) of peanuts or peanut-containing products in environments such as schools or on commercial aircraft are not backed by evidence that such measures work, which may raise an uncomfortable clash between accommodations that lack any medical evidence of necessity and a desire to provide measures that comfort our patients. CONCLUSION: There is little risk posed from non-oral exposure to peanut in the environment, from casual contact, proximity, or inhalation. If 5% of the population may tolerate a threshold of approximately 1.5 mg of peanut protein, this may help liberate behavior and situational-decision making regarding the necessity of certain avoidances and restrictions. Continued work is needed to dispel myths about the mechanisms of how peanut may induce an allergic reaction.

Assessment of peanut allergen Ara h1 in processed foods using a SWCNTs-based nanobiosensor.

The goals of this research were to develop a rapid single-walled carbon nanotube (SWCNT)-based biosensor and to employ it to commercial food products for Ara h1 detection. The SWCNT-based biosensor was fabricated with SWCNTs immobilized with antibody (pAb) through hybridization of 1-pyrenebutanoic acid succinimidyl ester (1-PBASE) as a linker. The resistance difference (ΔR) was calculated by measuring linear sweep voltammetry (LSV) using a potentiostat. Resistance values increased as the concentration of Ara h1 increased over the range of 1 to 105 ng/L. The specific binding of anti-Ara h1 pAb to antigen including Ara h1 was confirmed by both indirect ELISA kit and biosensor assay. The biosensor was exposed to extracts prepared from commercial processed food containing peanuts, or no peanuts, and could successfully distinguish the peanut containing foods. In addition, the application of present biosensor approach documented the precise detection of Ara h1 concentrations in commercially available peanut containing foods.

"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 screening approach, in terms of number of cases of peanut allergy prevented, quality-adjusted life years (QALY), and healthcare costs, although 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 $6556.69 (95%CI, $6512.76-$6600.62), compared with a cost of $7576.32 (95%CI, $7531.38-$7621.26) for skin test screening prior to introduction. From a US societal perspective, screening prior to introduction cost $654 115 322 and resulted in 3208 additional peanut allergy diagnoses. Both screening and nonscreening 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, and total healthcare costs compared to screening and in-office peanut introduction.

An Economic Analysis of a Peanut Oral Immunotherapy Study in Children.

BACKGROUND: Peanut oral immunotherapy (POIT) decreases the probability of accidental recurrent systemic reactions but reactions from the therapy itself are frequent. OBJECTIVE: The purpose of this economic analysis was to characterize the potential cost-effectiveness of POIT. METHODS: Cohort simulations were used to evaluate the effect of POIT for children with peanut allergy. A POIT with probiotic was used in the base-case simulation and long-term survival was modeled using age-adjusted mortality together with the risk of food allergy-associated mortality. RESULTS: The incremental POIT cost-effectiveness ratio was $2142 per quality-adjusted life-year. A mean number of 12.3 (95% CI, 12.0-12.5) and 2.0 (95% CI, 1.9-2.1) allergic reactions occurred in the POIT and avoidance groups over 20 years of simulation, with 2.3 (95% CI, 2.2-2.3) episodes of anaphylaxis treated with intramuscular epinephrine per subject in the POIT group and 1.1 (95% CI, 1.0-1.2) episodes per subject in the avoidance group. In sensitivity analyses, POIT was associated with lower rates of anaphylaxis than strict avoidance when the annual rate of accidental allergic reactions in the peanut avoidance group exceeded 25%, the annual rate of anaphylaxis in the POIT group dropped below 6%, or the probability of sustained unresponsiveness after 4 years of POIT was 68% or greater. CONCLUSIONS: POIT may be cost-effective in a long-term economic model. However, treated patients may experience a greater rate of peanut-associated allergic reactions and anaphylaxis. The analysis was sensitive to rates of accidental allergic reactions, therapy-associated adverse events, and likelihood of therapy-induced tolerance.

The economic effect and outcome of delaying oral food challenges.

BACKGROUND: Food specific IgE (sIgE) is a useful marker to assess predictability of oral food challenge (OFC) outcome. A threshold of less than 2 kUA/L for peanut, egg, and milk has been proposed as a 50% negative predictive value at which patients may pass an OFC. OBJECTIVE: To assess the economic effect and outcome of delaying OFCs. METHODS: A retrospective analysis was performed for peanut, egg, and milk OFCs conducted between 2001 and 2012 at a tertiary food allergy referral center. Delayed OFC was defined as greater than 12 months from the time the sIgE level became less than 2 kUA/L. Time to OFC was explored in association with skin prick test result (wheal size), OFC outcome, and the economic effect of delay. RESULTS: Of 319 challenges, 173 OFCs were delayed (54.2%) by a mean time of 35.5 months (range, 13-123 months) vs a mean time of 4.2 months in the 146 challenges that were not delayed (P < .001). The overall OFC passage rate was 89.9%. There was no association between delayed OFC and history of anaphylaxis, type of allergen, age at OFC, or challenge outcome. Delay in OFC was associated with an estimated mean economic cost of $12,203 per patient ($4,184 per 12 months) and $1,951,487 total (total delay, 5,597 months) in this population. CONCLUSION: Despite a 50% negative predictive value, more than 50% of OFCs were delayed in this population by a mean time of nearly 3 years. Delaying OFC is associated with increased costs, and quality improvement is needed to help decrease time to OFC and reduce the economic burden of food allergy on families and the health care system.

Allergen composition analysis and allergenicity assessment of Chinese peanut cultivars.

Peanut (Arachis hypogaea) is among the eight major food allergens in the world. Several attempts have been made to decrease or eliminate the allergenicity of peanut. Systemic screening of thousands of peanut cultivars may identify peanut with low allergenicity. In this study, the allergen compositions of 53 Chinese peanut cultivars were characterized, and their allergenicity to sera IgE of Chinese patients and in a mouse model was assessed. Contents of total protein and allergens were quantified by SDS-PAGE and densitometry analysis on gel. Although the contents of allergens broadly varied among cultivars, they were related to one another. The IgE binding capacity of cultivars was tested by ELISA, and their allergenicity was further evaluated in a mouse model by oral sensitization. Results showed that the allergenicity of peanut was affected by allergen composition rather than a single allergen. Peanut cultivars with low allergenicity may contain more Ara h 3/4 (24 kDa), Ara h 2 and less Ara h 3/4 (43, 38, and 36 kDa), Ara h 6. Screening based on allergen composition would facilitate the identification of low-allergenic peanut.

Crosslinking of peanut allergen Ara h 2 by polyphenol oxidase: digestibility and potential allergenicity assessment.

BACKGROUND: Peanut is one of the eight major food allergens. Its allergen, Ara h 2, can be recognized by over 90% of serum IgE samples from peanut-allergic patients. Therefore, reducing the allergenicity of Ara h 2 is especially important. RESULTS: In the present study, polyphenol oxidase (PPO), a protein cross-linking reaction catalyst that acts on tyrosine residue, was used to modify Ara h 2. After crosslinking, the microstructure, digestibility, IgG binding capability and IgE binding capability of Ara h 2 were analyzed. Cross-linking decreased the potential allergenicity of Ara h 2 by masking the allergen epitope, while the antigenicity of Ara h 2 changed slightly. After crosslinking, the apparent diameter of Ara h 2 was altered from 300 to 1700 nm or 220 nm, indicating that polymerization could either be inter- or intramolecular. Regarding digestibility, crosslinked Ara h 2 was relatively more easily digested by gastric fluid compared with the untreated Ara h 2, but much more difficult in the intestinal fluid. CONCLUSION: The crosslinking reaction catalyzed by PPO, as a non-thermal process, may be beneficial for avoiding food allergy. The reaction could mask allergen epitopes, decreasing the allergenicity of Ara h 2. © 2015 Society of Chemical Industry.

Assessment of the sensitizing potential of processed peanut proteins in Brown Norway rats: roasting does not enhance allergenicity.

BACKGROUND: IgE-binding of process-modified foods or proteins is the most common method for examination of how food processing affects allergenicity of food allergens. How processing affects sensitization capacity is generally studied by administration of purified food proteins or food extracts and not allergens present in their natural food matrix. OBJECTIVES: The aim was to investigate if thermal processing increases sensitization potential of whole peanuts via the oral route. In parallel, the effect of heating on sensitization potential of the major peanut allergen Ara h 1 was assessed via the intraperitoneal route. METHODS: Sensitization potential of processed peanut products and Ara h 1 was examined in Brown Norway (BN) rats by oral administration of blanched or oil-roasted peanuts or peanut butter or by intraperitoneal immunization of purified native (N-), heated (H-) or heat glycated (G-)Ara h 1. Levels of specific IgG and IgE were determined by ELISA and IgE functionality was examined by rat basophilic leukemia (RBL) cell assay. RESULTS: In rats dosed orally, roasted peanuts induced significant higher levels of specific IgE to NAra h 1 and 2 than blanched peanuts or peanut butter but with the lowest level of RBL degranulation. However, extract from roasted peanuts was found to be a superior elicitor of RBL degranulation. Process-modified Ara h 1 had similar sensitizing capacity as NAra h 1 but specific IgE reacted more readily with process-modified Ara h 1 than with native. CONCLUSIONS: Peanut products induce functional specific IgE when dosed orally to BN rats. Roasted peanuts do not have a higher sensitizing capacity than blanched peanuts. In spite of this, extract from roasted peanuts is a superior elicitor of RBL cell degranulation irrespectively of the peanut product used for sensitization. The results also suggest that new epitopes are formed or disclosed by heating Ara h 1 without glucose.

Quantitative risk assessment relating to adventitious presence of allergens in food: a probabilistic model applied to peanut in chocolate.

Peanut allergy is a public health concern, owing to the high prevalence in France and the severity of the reactions. Despite peanut-containing product avoidance diets, a risk may exist due to the adventitious presence of peanut allergens in a wide range of food products. Peanut is not mentioned in their ingredients list, but precautionary labeling is often present. A method of quantifying the risk of allergic reactions following the consumption of such products is developed, taking the example of peanut in chocolate tablets. The occurrence of adventitious peanut proteins in chocolate and the dose-response relationship are estimated with a Bayesian approach using available published data. The consumption pattern is described by the French individual consumption survey INCA2. Risk simulations are performed using second-order Monte Carlo simulations, which separately propagates variability and uncertainty of the model input variables. Peanut allergens occur in approximately 36% of the chocolates, leading to a mean exposure level of 0.2 mg of peanut proteins per eating occasion. The estimated risk of reaction averages 0.57% per eating occasion for peanut-allergic adults. The 95% values of the risk stand between 0 and 3.61%, which illustrates the risk variability. The uncertainty, represented by the 95% credible intervals, is concentrated around these risk estimates. Children have similar results. The conclusion is that adventitious peanut allergens induce a risk of reaction for a part of the French peanut-allergic population. The method developed can be generalized to assess the risk due to the consumption of every foodstuff potentially contaminated by allergens.

Assessment of the tolerance to lupine-enriched pasta in peanut-allergic children.

BACKGROUND: Reports of allergy to lupine derivatives (as de novo sensitization or cross-reactivity in subjects allergic to peanut) are increasing as their use in food products increases. OBJECTIVES: The aim of this study was to assess: (1) lupine tolerance in a group of children allergic to peanut, using lupine enriched-pasta instead of raw flour as has been done in previous clinical studies; (2) whether technological treatments of lupine modify its cross-reactivity or co-sensitization with peanut; (3) the role of lupine seed proteins in sensitization, and (4) to identify the eliciting doses (EDs) by using double-blind, placebo-controlled food challenges (DBPCFC). METHODS: Twelve patients with a history of clinical allergic reactions to peanut were evaluated by skin prick tests (SPTs), the ImmunoCAP test, immunoblotting, and DBPCFC. The 12 selected subjects were included in a trial where lupine-enriched pasta and placebo pasta were administered in a DBPCFC protocol. RESULTS: Positive clinical reactions were observed in two children, the EDs being 0.2 and 6.4 g of pasta, corresponding to 50 mg and 1.6 g of lupine proteins, respectively. Beta-conglutin was the protein most involved in SPT positivity. CONCLUSION: Lupine-enriched pasta can be tolerated by most subjects suffering from peanut allergy, but a sizeable minority (2/12 of them in this case) can develop potentially dangerous clinical reactions. Information about possible reactions to lupine derivatives by those allergic to peanuts must be included in the labelling of lupine-enriched products to protect consumers at risk.

Assessment of three human FcepsilonRI-transfected RBL cell-lines for identifying IgE induced degranulation utilizing peanut-allergic patient sera and peanut protein extract.

Specific IgE sera screening studies are employed to investigate protein cross-reactivity. Such nonfunctional immunochemical methods cannot measure the biological activity of proteins. Therefore, an assay using RBL cells transfected with human FcepsilonRI was developed. Our objective was to evaluate the degranulation of three cell-lines expressing either the alpha-(RBL-hEI(a)-2B12 and RBL-30/25cells) or alpha-, beta-, and gamma-subunits (RBL SX-38) of the human FcepsilonRI by beta-hexosaminidase release. Purified human IgE and serum-derived polyclonal IgE from peanut-allergic subjects following challenge with anti-IgE or peanut protein extract, respectively, were utilized. Robust degranulation was induced in all three: RBL-30/25 (84%), -hEI(a)-2B12 (54%), SX-38 (94%), respectively, using purified IgE+anti-human IgE. Good release (18%, 40-45%, and 65%, respectively) occurred for one peanut-allergic subject+peanut extract with all cell-lines. With serum from three other peanut-allergic subjects, no beta-hexosaminidase release occurred with RBL-hEI(a)-2B12 cells+peanut extract, while only serum from one subject induced good degranulation, 30% and 60%, respectively, with RBL-30/25 and RBL SX 38 cells. Consistent degranulation with a potent food allergen (peanuts) was not observed. The assay's utility in safety assessment, predictive value and reproducibility for evaluating the cross-reactivity of proteins with allergens needs further investigation with additional proteins and well-characterized sera.