Background
We have identified peroxidase I as a causative allergen for wheat-dependent exercise-induced anaphylaxis developed as pollen food allergy syndrome(PFAS-WDEIA) due to cross-reaction between wheat proteins and grass pollen allergens. The purpose of this study is to establish peroxidase I-specific IgE test and test its sensitivity and specificity to identify PFAS-WDEIA.
Subjects and Methods
Serum were obtained from 6 patients with PFAS-WDEIA, 18 patients with conventional WDEIA, 11 patients with hydrolyzed wheat protein allergy, 11 patients with hay fever, and 22 patients with red meat/crustacean allergy. Peroxidase I was purified upon chromatography steps, and peroxidase I-specific IgE test was established by CAP-FEIA system. Wheat, gluten and omega-5 gliadin-specific IgE were determined by CAP-FEIA system.
Summary of the results
Positive of peroxidase I-specific IgE test were 3 of 6 PFAS-WDEIA patients, but none of 18 conventional WDEIA, 11 hydrolyzed wheat allergy, 11 hay fever, nor 22 red meat/crustacean allergy patients. Sensitivity of peroxidase I-specific IgE test was 50% and its specificity was 100%, whereas, sensitivity of wheat-specific IgE test was 83.3% and its specificity was 74.2%, sensitivity of gluten-specific IgE test was 50% and its specificity was 79%, and sensitivity of omega-5 gliadin-specific IgE test was 0% and its specificity was 77.4%.
Conclusion
Wheat peroxidase I-specific IgE test is useful to identify patients with wheat-dependent exercise-induced anaphylaxis developed by sensitization to grass pollen.

Establishment of wheat peroxidase I-specific IgE test to identify wheat-dependent exercise-induced anaphylaxis developed by sensitization to grass pollen