Component-resolved in vitro diagnosis of hazelnut allergy in Europe DOI: https://doi.org/10.1016/j.jaci.2009.02.005 Abstract: Background Background Food allergy to hazelnut occurs both with and without concomitant pollen allergy. Objective We sought to evaluate a panel of hazelnut allergens for diagnosis of hazelnut allergy in Spain, Switzerland, and Denmark. Methods Fifty-two patients with a positive double-blind, placebo-controlled food challenge result with hazelnuts; 5 patients with a history of anaphylaxis; 62 patients with pollen allergy but hazelnut tolerance; and 63 nonatopic control subjects were included. Serum IgE levels to hazelnut extract, recombinant hazelnut allergens (rCor a 1.04, rCor a 2, rCor a 8, rCor a 11), and native allergens (nCor a 9, nCor a Bd8K, nCor a Bd11K) were analyzed by means of ImmunoCAP. Results Among patients with hazelnut allergy, 91% (Switzerland/Spain, 100%; Denmark, 75%) had IgE to hazelnut extract, 75% to rCor a 1.04, 42% to rCor a 2, 28% to rCor a 8, and 2% to rCor a 11. The highest rate of sensitization to Cor a 1.04 was found in the northern regions (Switzerland/Denmark, 100%; Spain, 18%), whereas IgE to the lipid transfer protein rCor a 8 prevailed in Spain (Spain, 71%; Switzerland, 15%; Denmark, 5%). IgE to profilin rCor a 2 was equally distributed (40% to 45%). Among control subjects with pollen allergy, 61% had IgE to hazelnut extract, 69% to rCor a 1.04, 34% to rCor a 2, 10% to rCor a 8, and 6% to rCor a 11. Conclusion Component-resolved in vitro analyses revealed substantial differences in IgE profiles of hazelnut allergic and hazelnut tolerant patients across Europe. All Author: Kirsten Skamstrup Hansen, MD, PhD'Correspondence information about the author MD, PhD Kirsten Skamstrup Hansen Email the author MD, PhD Kirsten Skamstrup Hansen, Barbara K. Ballmer-Weber, MD, PhD, Joaquin Sastre, MD, PhD, Jonas Lidholm PhD, Kerstin Andersson, PhD, Hubert Oberhofer, MD, Magdalena Lluch-Bernal, MD, Jonas ?stling, PhD, Lars Mattsson, PhD,Frauke Schocker, hD, Stefan Viet, PhD, Lars K. Poulsen, PhDPlumX Metric