Identification of allergens in Artocarpus heterophyllus, Moringa oleifera, Trianthema portulacastrum and Syzygium samarangense

Separating Fact from Fiction in the Diagnosis and Management of Food Allergy

IgE-mediated food allergies are an important public health problem, affecting 5 % of adults and 8 % of children, with numerous studies indicating that the prevalence is increasing. Food allergic reactions can range in severity from mild to severe and life threatening. Accurate diagnosis of food allergy is necessary not only to provide appropriate and potentially life-saving preventive measures but also to prevent unwarranted dietary restrictions. The diagnosis of food allergy has traditionally been based on clinical history and food specific IgE (sIgE) testing, including skin prick testing (SPT), serum tests, or both. These tests tend to be extremely sensitive, but positive test results to foods that are tolerated are common. Studies of allergen component-resolved diagnostics (CRD) show that adjuvant use of this modality may provide a more accurate assessment in the diagnosis of food allergy, though the reported benefits are questionable for a number of major allergens. Furthermore, diagnostic cutoff values have been difficult to determine for allergens where component testing has been demonstrated to be beneficial.

Real word evidence studies: Is it the way forward?

In this chapter we will first consider whether there is real evidence on the basis of literature for early descriptions in antiquity of pathogenic reactions after food intake that could be comparable to allergy, for instance in the scriptures of Hippocrates or Lucretius. On this topic we are skeptical, which is in agreement with the medical historian Hans Schadewaldt. We also assert that it is unlikely that King Richard III was the first food-allergic individual in medical literature. Most probably it was not a well-planned poisoning ('allergy') with strawberries, but rather a birth defect ('… his harm was ever such since his birth') that allowed the Lord Protector to bring Mylord of Ely to the scaffold in the Tower, as we can read in The History of King Richard III by Thomas More (1478-1535; published by his son-in-law, Rastell, in 1557). In 1912, the American pediatrician Oscar Menderson Schloss (1882-1952) was probably the first to describe scratch tests in the diagnosis of food allergy. Milestones in the practical diagnosis of food allergy are further discussed, including scratch tests, intradermal tests, modified prick tests and prick-to-prick tests. False-negative results can be attributed to the phenomenon of a 'catamnestic reaction' according to Max Werner (1911-1987), or to the fermentative degradation of food products. Prior to the discovery of immunoglobulin E, which marked a turning point in allergy diagnosis, and the introduction of the radioallergosorbent test in 1967, several more or less reliable techniques were used in the diagnosis of food allergy, such as pulse rate increase after food intake according to Coca, the leukopenic index, drop in basophils or drastic platelet decrease. The 'leukocytotoxic test' (Bryan's test), today called the 'ALCAT' test, shows no scientific evidence. The double-blind placebo-controlled food challenge test remains the gold standard in the diagnosis of food allergy. For the future, component-resolved diagnostics with the use of recombinant molecular allergens or chip arrays, such as the ISAC technique, hold a lot of promise. With regard to the clinical situation, a subjective selection is given, touching on the pollen-associated food allergies ('birch-mugwort-celery-spice syndrome'), as well as the new phenomenon of lethal food allergies that have appeared since the 1980s. Finally, rare ways of elicitation of a 'derivative allergy', first described by Erich Fuchs (1921-2008), for example by kissing, as well as 'oral allergy syndrome' and oral hyposensitization are considered.

SummaryThe diagnosis of IgE‐mediated food allergy based solely on the clinical history and the documentation of specific IgE to whole allergen extract or single allergens is often ambiguous, requiring oral food challenges (OFCs), with the attendant risk and inconvenience to the patient, to confirm the diagnosis of food allergy. This is a considerable proportion of patients assessed in allergy clinics. The basophil activation test (BAT) has emerged as having superior specificity and comparable sensitivity to diagnose food allergy, when compared with skin prick test and specific IgE. BAT, therefore, may reduce the number of OFC required for accurate diagnosis, particularly positive OFC. BAT can also be used to monitor resolution of food allergy and the clinical response to immunomodulatory treatments. Given the practicalities involved in the performance of BAT, we propose that it can be applied for selected cases where the history, skin prick test and/or specific IgE are not definitive for the diagnosis of food allergy. In the cases that the BAT is positive, food allergy is sufficiently confirmed without OFC; in the cases that BAT is negative or the patient has non‐responder basophils, OFC may still be indicated. However, broad clinical application of BAT demands further standardization of the laboratory procedure and of the flow cytometry data analyses, as well as clinical validation of BAT as a diagnostic test for multiple target allergens and confirmation of its feasibility and cost‐effectiveness in multiple settings.

A Case Series of Eosinophilic Esophagitis: Importance of Allergy Evaluation, Detection of Food Allergy and Avoidance Diet

ABSTRACTFood allergies are increasing in prevalence, and with it, IgE testing to foods is becoming more commonplace. Food-specific IgE tests, including serum assays and prick skin tests, are sensitive for detecting the presence of food-specific IgE (sensitization), but specificity for predicting clinical allergy is limited. Therefore, positive tests are generally not, in isolation, diagnostic of clinical disease. However, rationale test selection and interpretation, based on clinical history and understanding of food allergy epidemiology and pathophysiology, makes these tests invaluable. Additionally, there exist highly predictive test cutoff values for common allergens in atopic children. Newer testing methodologies, such as component resolved diagnostics, are promising for increasing the utility of testing. This review highlights the use of IgE serum tests in the diagnosis of food allergy.

Positive standardized food challenges represent the gold standard of diagnostic procedures in food-related reactions suspected to be of allergic nature. Skin prick testing and in-vitro diagnosis is helpful in most cases and can help to avoid cumbersome food challenges. This review considers recent progress in the use of in-vitro tests in the diagnosis of food allergy. Recent studies have addressed the characterization of 'new' food allergens which might now be used more accurately in the in-vitro diagnosis of food allergy. Additionally, while in-vitro tests must always be interpreted in line with the allergen tested and the clinical history, levels of food-specific immunoglobulin E can be correlated with the outcome of challenges to foods such as tree nuts as well as egg, according to two recent studies. Finally, epitope binding patterns of specific food allergens might help to predict which patients will most likely outgrow their food allergy, or which patients are clinically tolerant. This might help to avoid food challenges, which carry a risk for a potentially severe outcome. Recent studies of in-vitro diagnosis of food allergy have helped to provide safer and more accurate tests in the diagnosis and prognosis of food allergy.

Optimizing the diagnosis of peanut and tree nut allergy.

An accurate diagnosis of food allergy is extremely important to guide safe and yet not overly restrictive dietary management. The cornerstone of the diagnosis of food allergy is the clinical history; it allows appropriate selection of the allergens to be tested and interpretation of the results of allergy tests, namely Skin Prick Test (SPT), Specific IgE (sIgE) to allergen extracts and, more recently, specific IgE to allergen components and the Basophil Activation Test (BAT). SPT and sIgE to allergen extracts are very sensitive methods to detect IgE sensitization to a specific food and assess the possibility of spontaneous resolution. Cut-offs have been generated based on the probability of clinical reactivity during oral food challenges and can improve the specificity of SPT and sIgE, helping to confirm the diagnosis of food allergy. Specific IgE to allergen components refines food allergy diagnosis as it allows differentiating species-specific from cross-reactive allergens, aiding the differential diagnosis between a true and potentially severe food allergy from pollen-food syndrome or clinically irrelevant sensitization. The BAT is a new diagnostic test which has high specificity and sensitivity and can complement specific IgE, allowing the deferral of OFC in patients with a positive BAT. Depending on the likelihood of clinical allergy determined based on the combination of the history and the results of allergy tests, an oral food challenge may be indicated to confirm or exclude the diagnosis. Oral food challenge is the gold standard for the diagnosis of food allergy, but is a resource-intensive procedure with some level of risk involved; thus they are reserved for the equivocal cases. This review article discusses the above diagnostic techniques detailing the methods, utility, advantages and disadvantages.

Oral food challenge (OFC) is the gold standard for diagnosis of IgE-mediated and non-IgE mediated food allergy. It is usually conducted to make diagnosis, to monitor for resolution of a food allergy, or to identify the threshold of responsiveness. Clinical history and lab tests have poor diagnostic accuracy and they are not sufficient to make a strict diagnosis of food allergy. Higher concentrations of food-specific IgE or larger allergy prick skin test wheal sizes correlate with an increased likelihood of a reaction upon ingestion. Several cut-off values, to make a diagnosis of some food allergies (e.g., milk, egg, peanut, etc.) without performing an OFC, have been suggested, but their use is still debated. The oral food challenge should be carried out by experienced physicians in a proper environment equipped for emergency, in order to carefully assess symptoms and signs and correctly manage any possible allergic reaction. This review does not intend to analyse comprehensively all the issues related to the diagnosis of food allergies, but to summarize some practical information on the OFC procedure, as reported in a recent issue by The Expert Review of Food Allergy Committee of Italian Society of Pediatric Allergy and Immunology (SIAIP).

Food allergy diagnosis remains challenging due to the difficulty of distinguishing true clinical allergy from asymptomatic sensitization. Inaccurate diagnosis may result in unnecessary dietary restrictions, reduced quality of life, or, conversely, failure to identify individuals at risk of severe allergic reactions. This review critically analyzes the efficacy, limitations, and clinical utility of currently available diagnostic tests for food allergy, with particular emphasis on their ability to predict true clinical reactivity. A comprehensive literature review was conducted to evaluate the sensitivity, specificity, and predictive values of both traditional and emerging diagnostic modalities. English-language guidelines, systematic reviews, and key clinical studies published primarily within the past 15 years (up to 2025) were identified through PubMed and Google Scholar. Classic diagnostic tools, including skin prick testing (SPT) and serum-specific IgE (sIgE), were assessed alongside novel approaches such as component-resolved diagnostics (CRD), basophil activation test (BAT), mast cell activation test (MAT), atopy patch testing (APT), cytokine profiling, and omics-based diagnostics. Particular attention was given to how these tests compare with the oral food challenge (OFC), which remains the diagnostic gold standard. The findings demonstrate that while conventional tests offer high sensitivity and are valuable for initial risk assessment, their limited specificity often leads to overdiagnosis. Emerging molecular and cellular assays show improved specificity and functional relevance, especially in complex cases involving polysensitization or unclear clinical histories and may reduce reliance on OFCs in the future. However, accessibility, cost, and lack of standardization currently limit their widespread clinical application. Advances in artificial intelligence and data integration hold promise for improving diagnostic accuracy through enhanced interpretation of complex immunological data. Based on the synthesized evidence, this review proposes an evidence-based, stepwise, and individualized diagnostic algorithm for food allergy. Integrating clinical history, targeted testing, and selective use of OFCs can improve diagnostic certainty, enhance food safety, minimize unnecessary dietary avoidance, and optimize patient outcomes. The review underscores the need for continued research, standardization, and validation of novel diagnostic tools to support personalized and precise food allergy management.

Soybean is the most important oilseed crop that is grown in India. Horse purslane (Trianthema portulacastrumL.) infests soybean heavily, causing enormous yield losses and threatening the sustainability of the soybean production system. Information on the interference and economic threshold of horse purslane will be useful for the effective management of horse purslane in soybean. This will lead to the rationalization of herbicide use and the reduction of herbicide input into the environment. It was observed in this study that “a composite stand of weeds including horse purslane”, and 200 horse purslane plants per m2were equally competitive to soybean. These two treatments resulted in a higher dry weight, growth rate, and uptake of N, P, and K by the weeds and/or horse purslane, compared to the other treatments. They caused more reductions in soybean growth (dry weight, height, crop growth rate, net assimilation rate, and leaf area index) and resulted in a more significant yield reduction than did the other treatments. The weed density–crop yield and the relative leaf area–crop yield models were found to be equally effective in simulating soybean yield losses in relation to a wide range of horse purslane densities and the regression equations were a good fit. The quadratic equations revealed that a density of approximately six, five, and four horse purslane plants per m2would be the economic threshold levels of horse purslane in soybean cultivation, when considering the 70, 80, and 90% horse purslane control efficiencies, respectively, of the herbicide, lactofen.

Reconciling breast-feeding and early food introduction guidelines in the prevention and management of food allergy

BackgroundTo date, diagnosing food allergies in children still presents a diagnostic dilemma, leading to uncertainty concerning the definite diagnosis of peanut allergy, as well as to the need for strict diets and the potential need for adrenalin auto-injectors. This uncertainty in particular is thought to contribute to a lower quality of life. In the diagnostic process double-blind food challenges are considered the gold standard, but they are time-consuming as well as potentially hazardous. Other diagnostic tests have been extensively studied and among these component-resolved diagnostics appeared to present a promising alternative: Ara h2, a peanut storage protein in previous studies showed to have a significant predictive value.MethodsSixty-two out of 72 children, with suspected peanut allergy were analyzed using serum specific IgE and/or skin prick tests and specific IgE to several components of peanut (Ara h 1, 2, 3, 6, 8, 9). Subsequently, double-blind food challenges were performed. The correlation between the various diagnostic tests and the overall outcome of the double-blind food challenges were studied, in particular the severity of the reaction and the eliciting dose.ResultsThe double-blind provocation with peanut was positive in 33 children (53 %). There was no relationship between the eliciting dose and the severity of the reaction. A statistically significant relationship was found between the skin prick test, specific IgE directed to peanut, Ara h 1, Ara h 2 or Ara h 6, and the outcome of the food challenge test, in terms of positive or negative (P < .001). However, we did not find any relationship between sensitisation to peanut extract or the different allergen components and the severity of the reaction or the eliciting dose. There was no correlation between IgE directed to Ara h 3, Ara h 8, Ara h 9 and the clinical outcome of the food challenge.ConclusionsThis study shows that component-resolved diagnostics is not superior to specific IgE to peanut extract or to skin prick testing. At present, it cannot replace double-blind placebo-controlled food challenges for determination of the eliciting dose or the severity of the peanut allergy in our patient group.Electronic supplementary materialThe online version of this article (doi:10.1186/s12887-016-0609-7) contains supplementary material, which is available to authorized users.