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

ABSTRACT

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.