Wheat dependent exercise induced anaphylaxis: is this an appropriate terminology?

BACKGROUND The presentation of wheat dependent exercise induced anaphylaxis (WDEIA) can be variable. A high index of clinical suspicion is required to initiate the investigation pathway. Double blind placebo controlled food-exercise challenge is the gold standard investigation but the practicality of this test limits its application. AIM To critically analyse the symptoms of WDEIA and their correlation with serum specific IgE (sIgE) to romega-5-gliadin. METHODS 17 patients were tested for serum sIgE to romega-5-gliadin. The clinical response to a diet/exercise intervention protocol was used to assess specificity of a positive sIgE to romega-5-gliadin. Length of time to diagnosis, clinical likelihood scores, exercise intensity involved and the severity of allergic reactions were examined retrospectively. RESULT 8/10 patients with positive sIgE to romega-5-gliadin had a confirmed diagnosis of WDEIA. Half of the WDEIA patients had a prolonged time lag to diagnosis (32-62 months) and were initially diagnosed with idiopathic anaphylaxis or chronic idiopathic urticaria and angioedema. Only three patients had experienced life threatening symptoms (Mueller grading 4). A close association was observed between requirements of lower exercise intensity to provoke a reaction and diagnostic delay. CONCLUSION Specific IgE to romega-5-gliadin can provide supportive evidence for WDEIA without the need of a food-exercise challenge. The wheat-exercise association is not obvious in many patients, highlighting the need to consider WDEIA in the differential diagnosis of all patients presenting with idiopathic systemic reactions. The term anaphylaxis may be inappropriate and it is therefore worth considering an alternative terminology such as 'activity dependent wheat allergy' to describe this condition.