title: Ana o 3-specific IgE is a good predictor for clinically relevant cashew allergy in children.
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.
authors.affiliation: Department of Pediatrics, St. Marien-Hospital, Bonn, Germany.
authors.forename: L
authors.initials: L
authors.lastname: Lange
authors.affiliation: Institute of Medical Biometry, Informatics und Epidemiology (IMBIE), Bonn, Germany.
authors.forename: L
authors.initials: L
authors.lastname: Lasota
authors.affiliation: Department of Pediatrics, St. Marien-Hospital, Bonn, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Finger
authors.affiliation: Department of Pediatrics, St. Marien-Hospital, Bonn, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Vlajnic
authors.affiliation: Children's Hospital, Osnabrück, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Büsing
authors.affiliation: Department for Pediatrics, Helios Klinikum, Aue, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Meister
authors.affiliation: Children's Hospital, University of Cologne, Cologne, Germany.
authors.forename: I
authors.initials: I
authors.lastname: Broekaert
authors.affiliation: Kinderarztpraxis Laurensberg, Aachen, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Pfannenstiel
authors.affiliation: Kinderarztpraxis Laurensberg, Aachen, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Friedrichs
authors.affiliation: Children's Hospital, Hannover Medical School, Hannover, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Price
authors.affiliation: Department of Pediatric Pneumology and Immunology, Charité-Universitätsmedizin, Berlin, Germany.
authors.forename: V
authors.initials: V
authors.lastname: Trendelenburg
authors.affiliation: Department of Pediatric Pneumology and Immunology, Charité-Universitätsmedizin, Berlin, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Niggemann
authors.affiliation: Department of Pediatric Pneumology and Immunology, Charité-Universitätsmedizin, Berlin, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Beyer
mesh_terms: D000485:Allergens / Q000276:immunology*; D031021:Anacardium / Q000009:adverse effects*; D000918:Antibody Specificity / Q000276:immunology; D052179:Antigens, Plant / Q000276:immunology*; D002648:Child; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology*; D008297:Male; D021184:Nut Hypersensitivity / Q000175:diagnosis* / Q000276:immunology*; D010940:Plant Proteins / Q000276:immunology*; D011379:Prognosis; D012372:ROC Curve
chemical_list: D000485:Allergens; C502483:Ana o 3 protein, Anacardium occidentale; D052179:Antigens, Plant; D010940:Plant Proteins; D007073:Immunoglobulin E
keywords: Ana o 3; allergen-specific IgE; cashew; children; component-resolved diagnostics; food allergy