Abstract
Oral food challenge (OFC) is the gold-standard to diagnose food allergy; however, it is a labour and resource-intensive procedure with the risk of causing an acute allergic reaction, which is potentially severe. Therefore, OFC are reserved for cases where the clinical history and the results of skin prick test and/or specific IgE do not confirm or exclude the diagnosis of food allergy. This is a significant proportion of patients seen in Allergy clinics and results in a high demand for OFC. The basophil activation test (BAT) has emerged as a new diagnostic test for food allergy. With high diagnostic accuracy, it can be particularly helpful in the cases where skin prick test and specific IgE are equivocal and may allow reducing the need for OFC. BAT has high specificity, which confers a high degree of certainty in confirming the diagnosis of food allergy and allows deferring the performance of OFC in patients with a positive BAT. The diagnostic utility of BAT is allergen-specific and needs to be validated for different allergens and in specific patient populations. Standardisation of the laboratory methodology and of the data analyses would help to enable a wider clinical application of BAT.
Highlights
The gold-standard for the diagnosis of food allergy is oral food challenge (OFC) [1]
Whenever possible, the diagnosis of food allergy is established by a recent convincing history of an IgE-mediated allergic reaction to the culprit food combined with evidence of IgE sensitization to the same food by skin prick test (SPT) and/or serum specific IgE [3]
Different parameters of the basophil activation test (BAT) have been shown to reflect different characteristics of the allergic reactions, with the proportion of activated basophils reflecting the severity of allergic symptoms and the dose at which basophils react to allergen in vitro reflecting the dose of food protein at which patients reacted during OFC [46]
Summary
The gold-standard for the diagnosis of food allergy is oral food challenge (OFC) [1]. The results of BAT can be determined in terms of percentage of basophils expressing the defined activation marker or in terms of mean fluorescence intensity (MFI) by calculating the stimulation index, i.e. the ratio between the MFI of the selected condition and the MFI of the negative control. The former is usually used for CD63 as CD63 is not expressed in resting cells and its expression after activation is bimodal. We validated the diagnostic cut-offs determined for peanut allergy in an independent prospectively recruited population [15] and the specificity and positive predictive value of BAT reached 100 %. Origin of the study population (e.g. recruited from a specialized Allergy clinic or from the general population)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
