Clinical features and outcomes of patients with wheat-dependent exercise-induced anaphylaxis: a retrospective study.

Background: Wheat-dependent exercise-induced anaphylaxis (WDEIA) is a serious and potentially life-threatening form of wheat allergy. Further episodes can only be prevented by avoiding wheat ingestion or avoiding exercise after wheat intake. Anaphylaxis may recur in some patients post-diagnosis. This study aimed to analyze the clinical features and management/outcomes of WDEIA in China.

Methods: We retrospectively analyzed the clinical characteristics, and laboratory testing of 197 patients with WDEIA. After diagnosis, the patients were followed up as outpatients to evaluate dietary/exercise choice and clinical outcomes.

Results: Among the 197 WDEIA patients (median age, 37 years), 53.8% were male and 28.4% had other allergic disorders. The median duration of anaphylaxis before diagnosis was 16 months. Significant delays in diagnosis (> 1 years) were recorded in 52.7% of the patients, which has not decreased by years (P = 0.064). Exercise (83.8%), alcohol (12.2%), and nonsteroidal anti-inflammatory drugs (7.1%) were the most common cofactors. The most common clinical features were urticaria (100%), loss of consciousness (82.7%), dyspnea (50.8%), and hypotension (47.2%). Of the 197 eligible patients, 155 responded (78.7%), and 124 (80.0%) of which had no anaphylaxis post-diagnosis. A wheat-free diet prevented future anaphylaxis in 91.7% of the patients, followed by the avoidance of wheat combined with exercise (87%) and reduced wheat intake combined with exercise avoidance (80.5%).

Conclusion: The diagnosis of WDEIA is frequently delayed. Therefore, when patients present with unexplained anaphylaxis, the possibility of WDEIA should be considered. A wheat-free diet or avoiding wheat combined with exercise or reduced wheat combined with exercise avoidance helps to significantly reduce the onset of future anaphylaxis. However, approximately one-fifth of patients continue to experience anaphylaxis post-diagnosis. Thus, these patients must always carry epinephrine autoinjectors.