Wheat-dependent exercise-induced anaphylaxis in Chinese people: a clinical research on 33 cases with antigenic analysis of wheat proteins

Background Wheat-dependent exercise-induced anaphylaxis (WDEIA) is a severe allergic condition in which wheat ingestion together followed by physical exercise induces anaphylaxis. For patients with WDEIA, omega-5 gliadin is considered to be one of the major allergens. Aim To analyse the clinical features and allergen spectrum of WDEIA and to investigate the relationship between WDEIA and serum levels of platelet-activating factor (PAF), interleukin (IL)-9 and IL-33. Methods Medical histories and conditions of WDEIA cases were collected and summarized, with allergen tests of wheat proteins measured at the same visit. Of the 33 patients enrolled, 13 also had serum levels of PAF, IL-9 and IL-33 measured. The healthy control (HC) group consisted of 13 healthy individuals, who also underwent both the wheat-protein allergen tests and the inflammatory-mediator tests. Results All patients experienced severe allergic reaction during exercise after wheat ingestion. Manifestations of WDEIA included facial oedema, generalized urticaria and respiratory symptoms. Unconsciousness was also observed in 21 cases. In the patient group, 57.6% were confirmed as hypersensitive to glyceraldehyde-3-phosphate dehydrogenase (GAPDH), while 54.5% were allergic to omega-5 gliadin. PAF concentration was significantly higher in patients with WDEIA compared with HCs, whereas there was no significant difference in IL-9 or IL-33 between the two groups. Conclusions WDEIA is a rare type of anaphylaxis. GAPDH and omega-5 gliadin may be the most common allergy-causing wheat proteins for Chinese people. PAF may be associated with the onset and development of WDEIA.