The role of diagnostic tests and oral food challenge results to predict sesame allergy.

BACKGROUND The presence of sesame allergy and its importance are increasing. OBJECTIVE To determine the results of sesame and tahini oral food challenges (OFCs) and whether sesame-specific immunoglobulin E and skin prick tests (SPTs) accurately predicted sesame allergy in children. METHODS Patients with suspected sesame allergy between June 1, 2018, and June 1, 2020, were examined. RESULTS Of 92 patients (n = 65, 70.7% of the patients were boys) with a median age of 2 years (interquartile range, 1.2-3.8 years), 64 were reactive to tahini. Of 64 patients, 41 had a positive OFC result and 23 had a consistent history. Of 54 sesame OFCs, 10 patients had a positive outcome. Of 44 with a negative outcome of sesame OFC, 4 experienced allergic reactions with tahini at home and 22 patients had a positive result for tahini OFC. In multivariate logistic regression analysis, clinical reactivity of sesame (either a consistent history or a positive OFC) was positively associated with sesame SPT (odds ratio, 2.120; 95% confidence interval, 1.136-3.957; P = .01) and tahini SPT (odds ratio, 1.661; 95% confidence interval, 1.143-2.413; P = .008). Nevertheless, sesame-specific immunoglobulin E did not predict clinical reactivity. Tahini OFC outcomes were well predicted for both sesame and tahini SPTs (area under the curves of 0.937 and 0.896, respectively, P < .001 for both). A sesame SPT wheal size of 5.25 mm had 90.6% sensitivity, 82.1% specificity, and 5.1 positive likelihood ratio. For tahini SPT, the 6-mm threshold had 100% sensitivity, 82.1% specificity, and 5.6 positive likelihood ratio. CONCLUSION In the OFC, tahini emerged as a more optimal diagnostic tool to avoid false negatives. Furthermore, both high sesame and tahini SPT levels individually can help predict the diagnosis of sesame allergy.