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Measurement of Antigen-Specific IgA May be Useful in Children with Food Allergy
Sunday, March 6, 2016
South Exhibit Hall H (Convention Center)
Yosuke Baba, MD, PhD, Asuka Honjo, MD, Susumu Yamazaki, MD, PhD, Eisuke Inage, MD,PhD, Mari Mori, MD,PhD, Masato Kantake, MD, PhD, Yoshikazu Ohtsuka, MD,PhD, Toshiaki Shimizu, MD,PhD
Rationale: The IgE antibody contributes to immediate type allergic reactions, and the presence of the specific antibody can be an evidence of the diagnosis of allergic reactions; however, it is rare to see its elevation during infancy. On the other hand, the IgA antibody is massively produced in the intestinal Peyer’s patches. But the mechanism by which secretory IgA recognizes some antigens has not been clarified in food allergy.

Methods: We performed a retrospective study of patients with food allergy. The subjects of the present study are 56 patients that we performed oral food challenge (OFC) in our department. We investigated their serum levels of total IgE, antigen-specific IgE, antigen-specific IgA. Non-allergic children whose age and sex were about the same as the patients of food allergy were used as a control group. All patients agreed to the study with written consent.

Results: The measurement of serum levels of antigen-specific IgA was possible in a total of 32 patients. Children who were low levels in antigen-specific IgA have past histories of atopic dermatitis, and their serum levels of specific IgE were significantly higher, but their serum levels of antigen-specific IgA were significantly lower compared with control group. Especially, serum levels of ovomucoid-specific IgA were low in children who has ovalbumin allergy.

Conclusions: IgE antibody contributes to immediate type allergic reactions, and the presence of the specific antibody can be an evidence of the diagnosis of allergic reactions. Moreover, we suggested that measurement of antigen-specific IgA can be also useful in prediction of allergic reactions.