Comparison of multiplex arrays: AllergyChip and Alex2. IgE detection for inhalant allergens.

BACKGROUND Accurate diagnosis of IgE-mediated allergic diseases is crucial for effective management. This study compared the diagnostic performance of two multiplex allergy assays-AllergyChip and ALEX2-by measuring IgE reactivity to 31 inhalant allergens in serum from 90 participants.

OBJECTIVE To compare the diagnostic performance of AllergyChip with ALEX2 as reference method for specific IgE detection.

METHODS Agreement between the assays was evaluated by calculating overall (OPA), positive (PPA), and negative percentage agreement (NPA). Cohen's kappa measured agreement beyond chance. ROC analysis evaluated AllergyChip's ability to discriminate between positive and negative sIgE results. Spearman's correlation assessed concordance between sIgE classes, and Bland-Altman analysis evaluated quantitative agreement.

RESULTS AllergyChip showed substantial agreement with ALEX2 (OPA 88%, Cohen's kappa 0.792). ROC analysis showed excellent discrimination (AUC 0.891). Spearman's correlation (Rs 0.792) indicated strong agreement. However, AllergyChip had PPA below 70% for nine allergens, notably 0% for Phl p 12 and 30% for Bet v 2.

CONCLUSIONS AllergyChip performs well in detecting IgE to inhalant allergens and may be a viable alternative assay. However, its lower sensitivity for certain allergens suggests it should complement, rather than replace, ALEX2, particularly in cost-sensitive settings. Further studies are needed to confirm these findings and improve accuracy in multiplex allergy diagnostics.