Accurate and Reproducible Diagnosis of Peanut Allergy Using Epitope Mapping. Allergy Suarez-Farinas, M., Suprun, M., Kearney, P., Getts, R., Grishina, G., Hayward, C., Luta, D., Porter, A., Witmer, M., du Toit, G., Lack, G., Chinthrajah, R. S., Galli, S. J., Nadeau, K., Sampson, H. A. 2021

Abstract

BACKGROUND: Accurate diagnosis of peanut allergy is a significant clinical challenge. Here, a novel diagnostic blood test using the peanut Bead-Based Epitope Assay ("peanut BBEA") was developed utilizing the LEAP cohort and then validated using two independent cohorts.METHODS: The development of the peanut BBEA diagnostic test followed the National Academy of Medicine's established guidelines with discovery performed on 133 subjects from the non-interventional arm of the LEAP trial and an independent validation performed on 82 subjects from the CoFAR2 and 84 subjects from the POISED study. All samples were analyzed using the peanut BBEA methodology,which measures levels of IgE to two Ara h 2 sequential (linear) epitopes and compares their combination to a threshold pre-specified in the model development phase. When a patient has an inconclusive outcome by skin prick testing(or sIgE), IgE antibody levelsto this combination of two epitopes candistinguish whether the patient is "Allergic" or "Not Allergic." Diagnoses of peanut allergy in all subjects were confirmed by double-blind placebo-controlled food challenge and subjects' ages were 7-55 years.RESULTS: In the validation usingCoFAR2 and POISED cohorts, the peanut BBEA diagnostic test correctly diagnosed 93% of the subjects, with a sensitivity of 91%, specificity of 95%, a positive predictive value of 95% and negative predictive value of 91%.CONCLUSIONS: In validation of the peanut BBEA diagnostic test, the overall accuracy was found to be superior to existing diagnostic tests for peanut allergy including skin prick testing, peanut sIgE and peanut component sIgE testing.

View details for DOI 10.1111/all.14905

View details for PubMedID 33991353