Potential non-immunoglobulin E-mediated food allergies: comparison of open challenge and double-blind placebo-controlled food challenge.
OBJECTIVE
Comparison of open food challenge (OFC) with double-blind placebo-controlled food challenge (DBPCFC).


METHODS
Prospective sequential randomized challenges.


METHODS
Twenty adults with chronic allergy symptoms and at least 1 positive intradermal food wheal response recorded symptoms during DBPCFC and OFC provoked using organic foods, normal portions, and normal food preparation. Acoustic Rhinometry and biochemical tests were done during DBPCFC.


RESULTS
All patients reacted to at least 1 food and to all challenges with the same food, with multiorgan symptoms in the nose, nervous system, throat, and lung. There was a correlation in the type and severity of symptoms (P = 0.015) for OFC and DBPCFC, and both were significantly (P < 0.01) more severe than placebo. Compared with DBPCFC, OFC sensitivity was 66%, and positive predictive value was 89%.


CONCLUSIONS
This is the first study showing both concordance of OFC and DBPCFC and also that intradermal tests can identify reactive foods that can be verified by DBPCFC. Because most tests for IgE-mediated food allergy were negative, observed reactions were probably non-IgE mediated.
Wang
De Yun
de Y
Department of Otolaryngology, The National University of Singapore, Singapore.
Gordon
Bruce R
BR
Chan
Yiong Huak
YH
Yeoh
Kian Hian
KH
D004311:Double-Blind Method; D005512:Food Hypersensitivity / Q000175:diagnosis* / Q000276:immunology / Q000503:physiopathology; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology*; D007428:Intradermal Tests
D007073:Immunoglobulin E