Component-resolved allergy diagnosis by microarray: potential, pitfalls, and prospects

Diagnosis of IgE-mediated allergies is not always straightforward, as traditional tests can yield equivocal or negative results and provocation tests are hampered by several practical and ethical limitations. During the last decades two new in vitro techniques have entered the field of allergy diagnosis, that is, flow-assisted analysis of allergen-specific activated basophils and component-resolved diagnosis (CRD). This review focuses on component-resolved allergy diagnosis by microarray that has evolved from recent advances in molecular allergology and biochip technology. The technique allows a comprehensive analysis of individual sensitization profiles with multiplexed purified and recombinant allergens within a single run using only a minute amount of serum, providing information that largely exceeds the output from current sIgE capturing tools. Actually, multiplexing allows identification of diagnostic patterns that may facilitate the formulation of diagnostic algorithms. Although CRD by microarray sounds promising, the diagnostic performance requires further intensive assessment before it can enter mainstream application. In our opinion, the technique should currently be considered a complementary diagnostic tool rather than a first-line choice.