Basophil allergen threshold sensitivity and component‐resolved diagnostics improve hazelnut allergy diagnosis. Issue 9 (September 2015)

• Record Type: Journal Article
• Authors: Brandström, J.; Nopp, A.; Johansson, S. G. O.; Lilja, G.; Sundqvist, A.‐C.; Borres, M. P.; Nilsson, C.
• Is Part Of: Clinical & experimental allergy. Volume 45:Issue 9(2015:Sep.)
• Page Start: 1412
• Page End: 1418
• Publication Date: 2015-09
• Subjects: Allergy -- Periodicals; Immunology -- Periodicals; 616.97
• DOI: 10.1111/cea.12515
• Languages: English
• ISSNs: 0954-7894

Abstract

<abstract abstract-type="main" id="cea12515-abs-0001"> <title>Summary</title> <sec id="cea12515-sec-0001" sec-type="section"> <title>Background</title> <p>IgE sensitization to hazelnut is common, especially in birch endemic areas. However, its clinical significance often needs to be confirmed by a food challenge.</p> </sec> <sec id="cea12515-sec-0002" sec-type="section"> <title>Objective</title> <p>To evaluate the clinical significance of IgE antibodies to hazelnut components and basophil allergen threshold sensitivity (CD‐sens) to hazelnut, in relation to double‐blind placebo‐controlled food challenge (DBPCFC) in children with a suspected hazelnut allergy.</p> </sec> <sec id="cea12515-sec-0003" sec-type="section"> <title>Methods</title> <p>Forty children underwent a DBPCFC. CD‐sens to hazelnut as well as IgE antibodies to hazelnut and its components Cor a 1, Cor a 8, Cor a 9 and Cor a 14 were analysed. Serum tryptase was measured before, during and after DBPCFC.</p> </sec> <sec id="cea12515-sec-0004" sec-type="section"> <title>Results</title> <p>Eight children had a positive DBPCFC, and all of them had a high CD‐sens value to hazelnut. Of the 32 children that passed the DBPCFC, 31 were very low or negative in CD‐sens. A positive DBPCFC corresponded with significantly higher CD‐sens values (median 8.9, range 3.3–281) compared to children negative in challenge (median 0.05, range 0–34.7, <italic>P</italic> < 0.0001). Children positive in challenge also had higher levels of IgE‐ab to Cor a 9 and Cor a 14 (<italic>P</italic> < 0.01 and <italic>P</italic> < 0.001, respectively) compared with those with a negative challenge. In relation to the results from DBPCFC, the sensitivity of CD‐sens and IgE‐ab to Cor a 14 was excellent (100%) and the specificity was very high (> 97% and > 94%, respectively). Five of the eight patients positive at challenge showed an increase in tryptase > 20% compared to tryptase baseline levels.</p> </sec> <sec id="cea12515-sec-0005" sec-type="section"> <title>Conclusions and Clinical Relevance</title> <p>CD‐sens and component‐resolved diagnostics to hazelnut, used separately or in combination, may improve the diagnostic accuracy and safety and reduce overdiagnosis of hazelnut allergy.</p> </sec> </abstract>