Basophil activation test compared to skin prick test and fluorescence enzyme immunoassay for aeroallergen-specific Immunoglobulin-E

In this study, we compared the results of SPT, BAT and FEIA for different aeroallergens.We performed BAT, SPT and FEIA in 41 atopic subjects (symptomatic and with positive SPT for at least 1 of 9 common aeroallergens) and 31 non-atopic subjects (asymptomatic and with negative SPT).Correlations between SPT and BAT, SPT and FEIA, and BAT and FEIA results were statistically significant but imperfect. Using SPT as the "gold standard", BAT and FEIA were similar in sensitivity. However, BAT had lower specificity than FEIA. False positive (BATposSPTneg) results were frequent in those atopic subjects who were allergic by SPT to a different allergen and rare in non-atopic subjects. The false positivity in atopic subjects was due in part to high levels of serum Total-IgE (T-IgE) levels in atopic individuals that lead to basophil activation upon staining with fluorochrome-labeled anti-IgE.As an alternative to SPT in persons allergic to aeroallergens, BAT in its present form is useful for distinguishing atopic from non-atopic persons. However, BAT in its present form is less specific than FEIA when determining the allergen which a patient is allergic to. This is due to IgE staining-induced activation of atopic person's basophils and/or nonspecific hyperreactivity of atopic person's basophils.Allergen-specific IgE-mediated inflammation is thought to play a major role in the pathogenesis of allergic diseases including extrinsic asthma, rhinitis or eczema. Fc receptors of IgE bind to basophils and mast cells. Crosslinking of the bound IgE by allergens induces the release of inflammatory mediators. Skin prick testing (SPT) is an indirect measure of specific IgE bound to skin mast cells [1]. It has been widely used for the diagnosis of allergic disease because the results are available quickly. However, the utility of SPT is limited in patients with rash or dermographism or those taking antihistamines [2,3]. An alternative to SPT is the determination of serum concentration of specif