Ana o 3-specific IgE is a good predictor for clinically relevant cashew allergy in children DOI: 10.1111/all.13050 Abstract: Background: Component-resolved diagnostics using specific IgE to 2 S albumins has shown to be a valuable new option in diagnostic procedure. Ana o 3 is a 2 S albumin from cashew. The aim of this study was to investigate the role of Ana o 3-specific serum IgE in the diagnosis of cashew allergy and to identify cut-off levels to replace oral food challenges. Moreover, the value of additional determination of total IgE has been investigated. Methods: In a multicentre study, we analysed specific IgE to cashew extract and Ana o 3 as well as total IgE in children with suspected cashew allergy using the ImmunoCAP-FEIA and a standardized diagnostic procedure including oral challenges where indicated. Results: A total of 61 patients were included in the study. Forty-two were allergic to cashew, and 19 were tolerant. In receiver operating curves, Ana o 3 discriminates between allergic and tolerant children better than cashew-specific IgE with an area under the curve of 0.94 vs 0.78. The ratio of Ana o 3-specific IgE to total IgE did not further improve the diagnostic procedure. Probability curves for Ana o 3-specific IgE have been calculated, and a 95% probability could be estimated at 2.0 kU/l. Conclusions: Specific IgE to Ana o 3 is a valuable tool for the diagnosis of cashew allergy. Considering its positive predictive value, it might allow to make a considerable number of oral challenges superfluous. First Author: L. Lange Correspondence: Dr. Lars Lange, Department of Pediatrics,St. Marien-Hospital, Robert-Koch-Str. 1,53123 Bonn, Germany. All Authors: L. Lange, L. Lasota, A. Finger, D. Vlajnic, S. Busing € , J. Meister, I. Broekaert, C. Pfannenstiel,F. Friedrichs, M. Price, V. Trendelenburg, B. Niggemann & K. Beyer.