Making the Most of In Vitro Tests to Diagnose Food Allergy

Abstract

Various in vitro tests assess different aspects of the underlying immune mechanism of IgE-mediated food allergy. Some can be used for diagnostic purposes; specific IgE to allergen extracts is widely available; specific IgE to allergen components is used in most specialist centers, and the basophil activation test is becoming increasingly used clinically. IgE to allergen peptides, T-cell assays, allergen-specific/total IgE ratios, and allergen-specific IgG4/IgE ratios are currently reserved for research. Different factors can modulate the likelihood of IgE-mediated food allergy of a given allergy test result, namely, the patients' age, ethnicity, previous allergic reaction to the identified food, concomitant atopic conditions, and geographical location, and need to be taken into account when interpreting the allergy test results in the clinic. The importance of the specific food, the clinical resources available, and patient preferences are additional aspects that need to be considered when deciding whether an oral food challenge is required to reach an accurate diagnosis of IgE-mediated food allergy.

Selective nut‐eating in peanut or tree nut allergic children—How can molecular allergology help?

“…However, they advised that previously avoided tree nuts should be introduced with caution as there may be other allergens not tested thus there was a chance of a potentially severe allergic reaction. Although diagnostic food challenges were not performed to the tree nuts in this study, previous studies suggest a higher probability of a negative challenge with negative IgE to seed storage proteins . However, due to pollen‐food syndrome, localised symptoms may develop.…”

“…Although diagnostic food challenges were not performed to the tree nuts in this study, previous studies suggest a higher probability of a negative challenge with negative IgE to seed storage proteins. 3 However, due to pollen-food syndrome, localised symptoms may develop.…”

Recent developments and highlights in immune monitoring of allergen immunotherapy

“…Activated basophils are important biomarkers of allergic responses, reflecting specific IgE functional activity. In vitro basophil activation tests (BAT) may be useful in monitoring patients on AIT, by ex vivo measurements of CD63 or CD203c expression, basophil histamine release (BHR) or diamine oxidase (DAO), avoiding the risk of severe allergic reactions with in vivo allergen challenge . However, advances in practical aspects of the test are required for standardization and adaptation for use in routine laboratories.…”

“…Information that can be obtained from sequence analysis is highlighted vivo allergen challenge. [94][95][96][97] However, advances in practical aspects of the test are required for standardization and adaptation for use in routine laboratories. Due to their sequestration into tissues, mast cells remain difficult to investigate in the context of AIT and immune monitoring.…”

Food allergy phenotypes: The key to personalized therapy

“…Although some risk factors related to the severity of FA have been identified, no clear bio‐markers are available to predict the risk or the level of ED in real life or during an OFC. Studies have shown contradictory results about sIgE and SPT and individual risk assessment . Shreffler et al.…”