title: Food allergy: which tests are worth doing and which are not?
abstract: Adverse reactions to foods may arise by a variety of mechanisms, both immune (IgE and non-IgE) and non-immune mediated. This article considers those assays useful in the diagnosis of Type 1 hypersensitivity to foods (IgE-based) and, importantly, discusses those assays where evidence is lacking for their use. In all cases of suspected food allergy, a full clinical history is indispensable in facilitating diagnosis. Total serum IgE is not a suitable screen for food allergy. Suspect allergens may be confirmed by either skin prick testing or serological assays for specific IgE. Several studies suggest concentrations of food-specific IgE at which there is a high probability of reaction on food challenge. These cut-off levels are now being used by physicians to direct clinical advice. However, it is important to note that not all studies agree on these limits and the chosen cut-off is dependent on the population studied and the assay used.
authors.affiliation: Immunology and Immunogenetics, Pathology Sciences, North Bristol NHS Trust, Southmead Hospital, Bristol, UK.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Lock
authors.forename: David J
authors.initials: DJ
authors.lastname: Unsworth
mesh_terms: D000293:Adolescent; D000328:Adult; D000485:Allergens; D000918:Antibody Specificity; D002648:Child; D002675:Child, Preschool; D021181:Egg Hypersensitivity / Q000175:diagnosis / Q000453:epidemiology; D005512:Food Hypersensitivity / Q000175:diagnosis* / Q000453:epidemiology; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000175:diagnosis* / Q000453:epidemiology; D007118:Immunoassay; D007073:Immunoglobulin E / Q000097:blood*; D016269:Milk Hypersensitivity / Q000175:diagnosis / Q000453:epidemiology; D021183:Peanut Hypersensitivity / Q000175:diagnosis / Q000453:epidemiology; D012882:Skin Tests; D006113:United Kingdom / Q000453:epidemiology
chemical_list: D000485:Allergens; D007073:Immunoglobulin E