Clinical characteristics of soybean allergy in Europe: a double-blind, placebo-controlled food challenge study.
BACKGROUND
Soybean is a relevant allergenic food, but little is known about individual threshold doses in soy allergy.


OBJECTIVE
We sought to determine the clinical characteristics of soy allergy in Europe, including a dose-response curve.


METHODS
Patients with a history of soy allergy underwent a titrated, double-blind, placebo-controlled food challenge. A statistical model was used to calculate the risk of allergic consumers to experience an allergic reaction to soy. Sera were analyzed for specific IgE to soy, peanut, Bet v 1, and Gly m 4.


RESULTS
All patients but one responded primarily with subjective symptoms to the challenge followed by objective symptoms in 11 subjects, ranging from rhinitis up to a decrease in blood pressure. Cumulative threshold doses for allergic reactions ranged from 10 mg to 50 g for subjective symptoms and from 454 mg to 50 g for objective symptoms. The pattern of IgE reactivity against proteins with molecular weights of between approximately 10 and 70 kd was highly individual among the patients and did not correlate with the severity of symptoms.


CONCLUSIONS
When data are fitted by using a normal distribution statistical model, they predict that 1% of patients with soy allergy would react subjectively and objectively with 0.21 and 37.2 mg of soy protein, respectively.


CONCLUSIONS
Both the clinical and immunologic basis of soy allergy in Europe are highly complex, which affects the diagnosis of soy allergy and the advice given to patients with soy allergy in regard to risk management.
Ballmer-Weber
Barbara K
BK
Allergy Unit, Department of Dermatology, University Hospital, Zurich, Switzerland. barbara.ballmer@usz.ch
Holzhauser
Thomas
T
Scibilia
Joseph
J
Mittag
Diana
D
Zisa
Guliana
G
Ortolani
Claudio
C
Oesterballe
Morten
M
Poulsen
Lars K
LK
Vieths
Stefan
S
Bindslev-Jensen
Carsten
C
D000293:Adolescent; D000328:Adult; D000368:Aged; D000485:Allergens / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D003718:Denmark / Q000453:epidemiology; D004306:Dose-Response Relationship, Immunologic; D004311:Double-Blind Method; D005260:Female; D005512:Food Hypersensitivity / Q000175:diagnosis* / Q000453:epidemiology / Q000276:immunology*; D006801:Humans; D007223:Infant; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D010919:Placebos; D012882:Skin Tests; D013025:Glycine max / Q000276:immunology*; D013557:Switzerland / Q000453:epidemiology
D000485:Allergens; D010919:Placebos