Multiplex component-based allergen macroarray test is useful to predict clinical reactivity to tree nuts in children

Area of Science:

• Allergy and Immunology
• Pediatric Allergy
• Diagnostic Technologies

Background:

• Singleplex tests for tree nut (TN) allergies have diagnostic value but are costly and require excessive blood sampling.
• Limitations include a restricted number of detectable allergens.
• Multiplex macroarray testing offers a potential solution for comprehensive TN allergy diagnosis.

Purpose of the Study:

• To investigate the diagnostic utility of the multiplex macroarray (ALEX² test) for tree nut allergies in children.
• To evaluate the accuracy of specific allergen components in predicting clinical reactivity.
• To assess the ALEX² test as a stand-alone diagnostic tool.

Main Methods:

• Investigated 169 children with suspected tree nut allergies.
• Utilized skin prick tests (SPT) and component-resolved diagnostics (component- and extract-specific IgEs).
• Assessed clinical reactivity and tolerance to various tree nuts.

Main Results:

• Identified key allergen predictors for cashew, pistachio, hazelnut, and walnut allergies with high diagnostic accuracy (AUC 0.749-0.962).
• Over 93% of clinically reactive patients showed specific IgE positivity to key allergens (e.g., rPis v 1/rAna o 3 for pistachio/cashew).
• High concentrations of specific allergens demonstrated 100% specificity and positive predictive value (PPV) for certain nut allergies.

Conclusions:

• The multiplex macroarray (ALEX² test) is a useful and reliable diagnostic tool for pediatric tree nut allergies.
• It confirms and expands existing knowledge on TN allergy diagnostics.
• The ALEX² test can serve as a stand-alone diagnostic method in a bottom-up approach.