Two Different Composite Markers Predict Severity and Threshold Dose in Peanut Allergy

Area of Science:

• Allergy and Immunology
• Pediatric Clinical Research
• Diagnostic Biomarker Development

Background:

• Lack of reliable biological markers for evaluating peanut allergy (PA) severity and threshold doses during oral food challenges (OFCs).
• Need for cost-effective and safe surrogate markers to predict allergic reaction intensity.

Purpose of the Study:

• To identify and evaluate biological markers correlating with allergic reaction severity and threshold dose in children undergoing peanut OFC.
• To assess the diagnostic accuracy of these markers in a pediatric PA population.

Main Methods:

• Collected demographic and biological data from children undergoing peanut OFC, including basophil activation test (BAT) results.
• Stratified patients into severity groups (mild-to-moderate vs. severe) and cumulative threshold dose groups (low ≤100 mg vs. high >100 mg).
• Analyzed correlations between markers like Ara h 2-specific IgE, FcεRI, and fMLP-positive controls with reaction severity and threshold dose.

Main Results:

• High concordance (96%) between OFC and BAT for PA diagnosis.
• Higher Ara h 2-specific IgE and FcεRI-positive control values correlated with severe peanut allergic reactions.
• A 2-marker combination (IgE, FcεRI) showed 92% sensitivity and 82% specificity for severe reactions.
• A 4-variable composite marker demonstrated 97% sensitivity and 61% specificity for low cumulative threshold dose in children.

Conclusions:

• Composite markers, incorporating both allergen-specific and non-allergen-specific basophil activation test parameters, are associated with peanut allergy severity and threshold dose in children.
• These findings suggest potential for improved prediction of reaction severity and dose thresholds in pediatric PA.