Basophil allergen threshold sensitivity and component-resolved diagnostics improve hazelnut allergy diagnosis

• BackgroundIgE sensitization to hazelnut is common, especially in birch endemic areas. However, its clinical significance often needs to be confirmed by a food challenge. ObjectiveTo 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. MethodsForty 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. ResultsEight 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, P<0.0001). Children positive in challenge also had higher levels of IgE-ab to Cor a 9 and Cor a 14 (P<0.01 and P<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. Conclusions and Clinical RelevanceCD-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.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Lungmedicin och allergi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Respiratory Medicine and Allergy (hsv//eng)

Nyckelord

basophils

CD-sens

flow cytometry

IgE antibody

molecular allergology

oral food challenge

tryptase

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)