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Accurate diagnosis of food allergies is vital to identify patients who may have severe, life-threatening allergic reactions, and to exclude suspected allergies that could lead to unnecessary dietary restrictions.
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Traditional tests for food allergy have several limitations; skin prick testing and food-specific IgE levels are excellent tools for detecting sensitization to foods, but, often, positive tests are clinically irrelevant. Although oral food challenges are the gold standard for diagnosing
Optimizing the Diagnosis of Food Allergy
Section snippets
Key points
Standard diagnostic tests
The typical diagnostic routine (Fig. 1) begins with a medical history to determine whether the symptoms are potentially related to ingestion of specific foods; whether adverse reactions are allergic in nature; and, if so, the likely pathophysiologic basis. Knowledge of the epidemiology of food allergy and details of the history may identify potential triggers to which simple tests, such as SPT and sIgE, can be applied and interpreted in the context of the history and a knowledge of test
Component-Resolved Diagnostics
Allergen CRDs have garnered a lot of attention in recent years, with the hope of offering a more accurate assessment of allergic status. Instead of using crude allergen extracts consisting of a mixture of components, CRD measures IgE to individual allergen proteins. In recent years, several studies on a variety of food allergens have demonstrated that CRD can improve the specificity of allergy testing.
The usefulness of CRD has been best demonstrated in studies on peanut allergy.33 In 2004,
Future diagnostic tests
Several tests are undergoing study and may have advantages compared with currently available tests for diagnosing food allergy (Table 2).
Controversial and unproven tests
There are several tests that have been examined that are not recommended for the diagnosis of food allergy. Intradermal testing should not be used. Not only is intradermal injection of allergens overly sensitive, but it also carries a higher risk of adverse reactions than SPT.1, 83 The National Institute of Allergy and Infectious Diseases expert guidelines published in 2010 also suggest that atopy patch testing (APT) should not be used in the routine evaluation of noncontact food allergy.
Future considerations and summary
The work-up of a potential food allergy can be a complex assessment involving the clinical history, SPT, and sIgE levels, although ultimately these diagnostic tools may be inadequate to definitively diagnose a food allergy. Currently, OFCs remain the most definitive test in the diagnosis of food allergy, but they are time consuming, costly, and have the potential to elicit a severe allergic reaction. In recent years, several different testing modalities, including CRD, basophil activation
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2023, Food Research InternationalSeparating Fact from Fiction in the Diagnosis and Management of Food Allergy
2022, Journal of PediatricsCharacteristics of patients with spontaneous resolution of sesame allergy
2022, Annals of Allergy, Asthma and ImmunologyCitation Excerpt :A combination of commercial sesame extract and tahini yielded higher sensitivity and specificity.20 The mean wheal diameter of SPT with tahini in our study was larger at baseline compared with the mean wheal diameter with commercial sesame extract, because of the higher protein concentration in tahini and because relevant labile proteins may not be present in the commercial extracts.21,22 Higher sensitivity of SPT with tahini raises the concern on mislabeling patients as having allergy and biased results.
Precision medicine in allergic diseases
2022, Revista Medica Clinica Las CondesEvolving Interpretation of Screening and Diagnostic Tests in Allergy
2021, Journal of Allergy and Clinical Immunology: In PracticeThe Revenge of Unintended Consequences of Anaphylaxis-Risk Overdiagnosis: How Far We Have Come and How Far We Have to Go
2021, Journal of Allergy and Clinical Immunology: In PracticeCitation Excerpt :The potential benefit of screening is prevention of a first allergic reaction to peanut at home; however, many of these reactions are nonsevere19 and there has never been a known or reported life-threatening reaction or fatality reported on first ingestion of peanut in infancy, although underreporting of fatalities for anaphylaxis likely occurs in all age ranges.1,27,28 There are significant harms with preemptive screening prior to peanut introduction related to the poor specificity of first-line allergy testing.29,30 Preemptive screening may result in unnecessary peanut avoidance and overdiagnosis of peanut allergy19; it may not even be feasible in large populations owing to the high prevalence of eczema and egg allergy within the infant population.