Abstract
Background:
Hazelnut represents one of the most important food allergens. Yet, sensitization to hazelnut is often randomly detected during routine diagnostic workup without a clear-cut history of allergy. The aim of this study was to assess the diagnostic usefulness of recombinant hazelnut components and whole hazelnut extract for the prediction of clinical reactivity in sensitized children.
Methods:
Fifty-three consecutive children were investigated who underwent oral food challenge (OFC) due to positive in vitro test results and/or cutaneous reactions after hazelnut ingestion. Determination of specific immunoglobulin E (sIgE) against allergen extracts and recombinant hazelnut components had been performed in all patients prior to OFC.
Results:
OFC revealed hazelnut allergy in 19 children (36%). At a mean total IgE of 518 kU/L, sIgE to hazelnut extract was significantly higher in allergic than in tolerant children (38 vs. 13 kU/L). In contrast, no significant difference in sIgE levels against allergen components was detected. A ratio of rCor a 1 to hazelnut extract sIgE levels >1 predicted hazelnut tolerance with a sensitivity and a negative predictive value of 100%. The corresponding specificity (47%) and positive predictive value (51%) were low.
Conclusions:
In the present study, a ratio of rCor a 1 to hazelnut extract sIgE >1 predicted hazelnut tolerance during OFC in children with suspected hazelnut allergy. However, further investigations in larger populations are warranted to investigate the transferability of these results to other patient populations. Until then, OFC remain the diagnostic gold standard for the definitive diagnostic workup of suspected food allergy.
Get full access to this article
View all access options for this article.