Comparison of diagnostic performances of two IgE biochips: ISAC (R) and ALEX2 (R)

Aim of the study. - The aim is to compare the diagnostic performances of two multi-allergenic IgE microarrays of different composition and principle. Patients and methods. - Twenty-one patients with polysensitivity or unexplained anaphylaxis were testedby two microarrays: the ISAC (R) biochip and the ALEX2 (R) biochip. Results. - The overall agreement of results between the two biochips was very good (97.8%), Analysis by molecular protein family shows a higher frequency of ALEX (R) positivity for LTP (7.4% versus 5.8 %), while the opposite is true for PR-10 (14.9% for ISAC (R) versus 11.9% for ALEX (R)). However, the concentrations observed in ALEX (R) for PR-10 are higher. As expected, a pretreatment by a specific inhibitor blocked the interference of anti-CCD IgE in ALEX (R) biochip. The analysis by patient allowed to highlight sensitizations tosome specific components of each biochip: meat, fish, and pistachio present only on ALEX2 (R) or alpha-Galon ISAC (R). Conclusion. - The results obtained with the 2 biochips are generally consistent for common allergens. Amore complete chip combining extracts as molecular allergens not available in individual tests shouldfind its place in the exploration of unexplained anaphylaxis but the choice and number of allergens testedshould evolve to best meet clinical needs. (c) 2023 Published by Elsevier Masson SAS.