Basophil activation test (BAT) or the mast cell activation test (MAT) are two in vitro tests that are currently being studied in food allergy as diagnostic tools as an alternative to oral food challenges (OFCs). We conducted a meta-analysis on BAT and MAT, assessing their specificity and sensitivity in diagnosing peanut allergy. Six databases were searched for studies on patients suspected of having peanut allergy. Studies using BAT or MAT to peanut extract and/or component as diagnostic tools with results given in percentage of CD63 activation were included in this meta-analysis. Study quality was evaluated with the QUADAS-2 tool. On the 11 studies identified, eight focused exclusively on children, while three included a mixed population of adults and children. Only one study provided data on MAT, precluding us from conducting a statistical analysis. The diagnostic accuracy of BAT was higher when stimulated with peanut extract rather than Ara h 2 with a pooled specificity of 96% (95% CI: 0.89-0.98) and sensitivity of 0.86 (95% CI: 0.74-0.93). The sensitivity and specificity of BATs in discriminating between allergic and sensitized patients were studied as well, with pooled analysis revealing a sensitivity of 0.86 (95% CI: 0.74; 0.93) and a specificity of 0.97 (95% CI: 0.94, 0.98). BATs, when stimulated with peanut extracts, exhibit a satisfactory sensitivity and specificity for the diagnosis of peanut allergy and can help to discriminate between allergic individuals and those only sensitized to peanuts. More investigations on the potential for MATs diagnostic methods are warranted.

Peanut allergy is a leading cause of severe food reactions. This meta-analysis evaluates the efficacy and safety of epicutaneous immunotherapy (EPIT) compared to placebo for peanut-allergic individuals. After prospectively registering on PROSPERO, we searched three databases (PubMed, Google Scholar, and Cochrane CENTRAL) and 2 trial registries till September 2023. Analysis was conducted via RevMan where data was computed using risk ratios (RR). The Cochrane Risk of Bias tool and GRADE criteria were used to appraise and evaluate the evidence. From 4927 records, six multicenter randomized placebo-controlled trials comprising 1453 participants were included. The 250 µg EPIT group had a significant increase in successful desensitization compared to placebo (RR: 2.13 (95% C.I: 1.72, 2.64), P < 0.01, I2 = 0%), while the 100 µg EPIT group did not (RR: 1.54 (95% C.I: 0.92, 2.58), P = 0.10, I2 = 0%) (moderate certainty evidence). Moreover, there was a significant increase in local (RR: 1.69 (95% C.I: 1.06, 2.68), P = 0.03, I2 = 89%) and systemic adverse events (RR: 1.75 (95% C.I: 1.14, 2.69), P = 0.01, I2 = 0%) with EPIT. Additionally, individuals administered EPIT have an increased probability of requiring rescue medications like epinephrine (RR: 1.91 (95% C.I: 1.12, 3.28), P = 0.02, I2 = 0%) and topical corticosteroids (RR: 1.49 (95% C.I: 1.29, 1.73), P < 0.01, I2 = 0%) to treat adverse events. The association of adverse events post-treatment including anaphylaxis (RR: 2.31 (95% C.I: 1.00, 5.33), P = 0.05, I2 = 36%), skin/subcutaneous disorders like erythema or vesicles (RR: 0.93 (95% C.I: 0.79, 1.08), P = 0.33, I2 = 0%), and respiratory disorders like dyspnea or wheezing (RR: 0.94 (95% C.I: 0.77, 1.15), P = 0.55, I2 = 0%) with EPIT is inconclusive. EPIT, although effective in desensitization, is linked to an increased risk of adverse events. PROSPERO registration: CRD42023466600.

UNASSIGNED: Background. The review was structured in the following sections: 1) Cow\'s Milk Proteins Allergy (CMA), 2) Food Allergy to Peanuts and 3) Prevention of Food Allergy. In CMA, studies indicate that extensively hydrolyzed casein formula supplemented with Lactobacillus Rhamnosus GG aids in acquiring tolerance to cow\'s milk proteins, resolving gastrointestinal symptoms and preventing of other allergic manifestations. In peanut oral immunotherapy (OI), supplementation with Lactobacillus Rhamnosus CGMCC 1.3724 appears to promote sustained desensitization. However, the evidence supporting probiotics for preventing food allergies lacks robustness. Current evidence supports the use of oligosaccharides from breast milk in the first months of life for preventing atopic dermatitis, FA and asthma Methods. A PubMed/Medline search was carried out on articles published between 2011 and 2021 with the following query: (\"Food Hypersensitivity\"[Mesh]) AND ((\"Probiotics\"[Mesh]) OR (\"Prebiotics\"[Mesh])). Subsequently, the titles and abstracts were analysed and selected according to established criteria. After full reading of these articles, 54 were included and a narrative review was performed. Results. The review was structured in the following sections: 1) Cow\'s Milk Proteins Allergy (CMA), 2) Food Allergy to Peanuts and 3) Prevention of Food Allergy. In CMA, studies indicate that extensively hydrolyzed casein formula supplemented with Lactobacillus Rhamnosus GG aids in acquiring tolerance to cow\'s milk proteins, resolving gastrointestinal symptoms and preventing of other allergic manifestations. In peanut oral immunotherapy (OI), supplementation with Lactobacillus Rhamnosus CGMCC 1.3724 appears to promote sustained desensitization. However, the evidence supporting probiotics for preventing food allergies lacks robustness. Current evidence supports the use of oligosaccharides from breast milk in the first months of life for preventing atopic dermatitis, FA and asthma. Conclusions. The potential of probiotics to be used as therapeutic adjuvants in CMA and peanut OI is promising. However, there is inconsistency regarding the type of probiotic, the dose and duration of supplementation. Further studies are needed to clarify the role of probiotics and prebiotics in FA.

Earlier egg and peanut introduction probably reduces risk of egg and peanut allergy, respectively, but it is uncertain whether food allergy as a whole can be prevented using earlier allergenic food introduction.
To investigate associations between timing of allergenic food introduction to the infant diet and risk of food allergy.
In this systematic review and meta-analysis, Medline, Embase, and CENTRAL databases were searched for articles from database inception to December 29, 2022. Search terms included infant, randomized controlled trial, and terms for common allergenic foods and allergic outcomes.
Randomized clinical trials evaluating age at allergenic food introduction (milk, egg, fish, shellfish, tree nuts, wheat, peanuts, and soya) during infancy and immunoglobulin E (IgE)-mediated food allergy from 1 to 5 years of age were included. Screening was conducted independently by multiple authors.
The Preferred Reporting Items for Systematic Reviews and Meta-analyses guideline was used. Data were extracted in duplicate and synthesized using a random-effects model. The Grading of Recommendations, Assessment, Development, and Evaluation framework was used to assess certainty of evidence.
Primary outcomes were risk of IgE-mediated allergy to any food from 1 to 5 years of age and withdrawal from the intervention. Secondary outcomes included allergy to specific foods.
Of 9283 titles screened, data were extracted from 23 eligible trials (56 articles, 13 794 randomized participants). There was moderate-certainty evidence from 4 trials (3295 participants) that introduction of multiple allergenic foods from 2 to 12 months of age (median age, 3-4 months) was associated with reduced risk of food allergy (risk ratio [RR], 0.49; 95% CI, 0.33-0.74; I2 = 49%). Absolute risk difference for a population with 5% incidence of food allergy was -26 cases (95% CI, -34 to -13 cases) per 1000 population. There was moderate-certainty evidence from 5 trials (4703 participants) that introduction of multiple allergenic foods from 2 to 12 months of age was associated with increased withdrawal from the intervention (RR, 2.29; 95% CI, 1.45-3.63; I2 = 89%). Absolute risk difference for a population with 20% withdrawal from the intervention was 258 cases (95% CI, 90-526 cases) per 1000 population. There was high-certainty evidence from 9 trials (4811 participants) that introduction of egg from 3 to 6 months of age was associated with reduced risk of egg allergy (RR, 0.60; 95% CI, 0.46-0.77; I2 = 0%) and high-certainty evidence from 4 trials (3796 participants) that introduction of peanut from 3 to 10 months of age was associated with reduced risk of peanut allergy (RR, 0.31; 95% CI, 0.19-0.51; I2 = 21%). Evidence for timing of introduction of cow\'s milk and risk of cow\'s milk allergy was very low certainty.
In this systematic review and meta-analysis, earlier introduction of multiple allergenic foods in the first year of life was associated with lower risk of developing food allergy but a high rate of withdrawal from the intervention. Further work is needed to develop allergenic food interventions that are safe and acceptable for infants and their families.

With increasing prevalence of peanut allergy (PA) globally and the greater risk of potential reactions occurring due to the leading role of nuts in food products, PA has become a significant public health concern over the past decade, affecting up to 5 million of the US adult population. This review details updates and advances in prevalence, diagnosis, and immunotherapies that have occurred over the past year.
Therapeutic and diagnostic advances remain at the forefront of research and have continued to push the food allergy (FA) field forward to provide a promising role in the detection and treatment of PA. The FA field has researched significant advances in peanut immunotherapy, biomarker diagnosis, and quality of life (QoL) improvement.
Given the burden and consequences for individuals with PA, these advances delivered in clinical practice can significantly improve the QoL of individuals with PA and their caregivers. Ongoing studies will continue to investigate long-term outcome measures of desensitisation and effective management plans tailored to the families\' needs.

Peanut hypersensitivity is one of the top causes of food-related allergic responses and death in high-income countries. As a result, the goal of this study was to see if various forms of immunotherapies can help reduce the severity of peanut hypersensitivity reactions. From 2019 to 2021, a systematic search of PubMed, Web of Science, Wiley online library, and Science Direct was done. Peanut immunotherapy (PIT) clinical trials were considered. There were 19 trials with a total of 1565 participants. Twelve were on oral immunotherapy (OIT), two on sublingual immunotherapy (SLIT), two on subcutaneous immunotherapy (SCIT), two on epicutaneous immunotherapy (EPIT), and one was a comparison of SLIT and OIT. Desensitization was achieved by 74.3% of those who received OIT, 11% of those who received SLIT, 61% of those who received SCIT, and 49% of those who received EPIT. The majority of adverse events (AE) were mild to moderate. Those requiring epinephrine, on the other hand, were moderate to severe and were more common in the therapy groups. This systematic review showed that the current PIT regimens can accomplish desensitization regardless of the route of administration, with an acceptable safety profile.

Eliciting doses (EDs) (eg, ED01 or ED05 values, which are the amounts of allergen expected to cause objective symptoms in 1% and 5% of the population with an allergy, respectively) are increasingly being used to inform allergen labeling and clinical management. These values are generated from food challenge, but the frequency of anaphylaxis in response to these low levels of allergen exposure and their reproducibility are unknown.
Our aim was to determine (1) the rate of anaphylaxis in response to low-level peanut exposure and (2) the reproducibility of reaction thresholds (and anaphylaxis) at food challenge.
We conducted a systematic review and individual participant data meta-analysis of studies that reported at least 50 individuals with peanut allergy reacting to peanut at double-blind, placebo-controlled food challenge (DBPCFC) and were published between January 2010 and September 2020. Risk of bias was assessed by using National Institute for Clinical Excellence methodologic checklists.
A total of 19 studies were included (covering a total of 3151 participants, 534 of whom subsequently underwent further peanut challenge). At individual participant data meta-analysis, 4.5% (95% CI, 1.9% to 10.1%) of individuals reacted to 5 mg or less of peanut protein with anaphylaxis (moderate heterogeneity [I2 = 57%]). Intraindividual thresholds varied by up to 3 logs, although this variation was limited to a half-log change in 71.2% (95% CI, 56.2% to 82.6%) of individuals. In all, 2.4% (95% CI, 1.1% to 5.0%) of patients initially tolerated 5 mg of peanut protein but then reacted to this dose at subsequent challenge (low heterogeneity [I2 = 16%]); none developed anaphylaxis.
Around 5% of individuals reacting to an ED01 or ED05 level of exposure to peanut might develop anaphylaxis in response to that dose. This equates to 1 and 6 anaphylaxis events per 2500 patients exposed to an ED01 or ED05 dose, respectively, in the broader population of individuals with peanut allergy.

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.

Given the burden of disease and the consequences of a diagnosis of peanut allergy, it is important that peanut allergy be accurately diagnosed so that an appropriate treatment plan can be developed. However, a test that indicates there is peanut sensitization present (eg, a \"positive\" test) is not always associated with clinical reactivity. This practice parameter addresses the diagnosis of IgE-mediated peanut allergy, both in children and adults, as pertaining to 3 fundamental questions, and based on the systematic reviews and meta-analyses, makes recommendations for the clinician who is evaluating a patient for peanut allergy. These questions relate to when diagnostic tests should be completed, which diagnostic tests to utilize, and the utility (or lack thereof) of diagnostic testing to predict the severity of a future allergic reaction to peanut.

This systematic review of ways to prevent immediate-onset/IgE-mediated food allergy will inform guidelines by the European Academy of Allergy and Immunology (EAACI).
The GRADE approach was used. Eleven databases were searched from 1946 to October 2019 for randomized controlled trials (and large prospective cohort studies in the case of breastfeeding). The studies included heterogeneous interventions, populations, and outcomes and so were summarized narratively.
Forty-six studies examined interventions to reduce the risk of food allergy in infancy (up to 1 year) or early childhood. The following interventions for pregnant or breastfeeding women and/or infants may have little to no effect on preventing food allergy, but the evidence is very uncertain: dietary avoidance of food allergens, vitamin supplements, fish oil, probiotics, prebiotics, synbiotics, and emollients. Breastfeeding, hydrolyzed formulas, and avoiding cow\'s milk formula may not reduce the risk of cow\'s milk protein allergy; however, temporary supplementation with cow\'s milk formula in the first week of life may increase the risk of cow\'s milk allergy. Introducing well-cooked egg, but not pasteurized raw egg, from 4 to 6 months probably reduces the risk of hen\'s egg allergy. Introducing regular peanut consumption into the diet of an infant at increased risk beginning from 4 to 11 months probably results in a large reduction in peanut allergy in countries with a high prevalence. These conclusions about introducing peanut are based on moderate certainty evidence, from single trials in high-income countries.
Sixty percent of the included studies were published in the last 10 years, but much still remains to be understood about preventing food allergy. In particular, there is a need to validate the potential benefits of early introduction of food allergens in a wider range of populations.