Lucinda Kennard1, Iason Thomas2, Krzysztof Rutkowski2, Vian Azzu3, Patrick F K Yong4, Bogusia Kasternow4, Hannah Hunter2, Naeema M O Cabdi5, Alla Nakonechna6, Annette Wagner7. 1. Department of Allergy, Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom. Electronic address: LK@doctors.org.uk. 2. Department of Allergy, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom. 3. Department of Medicine (Gastroenterology and Hepatology Subdivision), University of Cambridge, Cambridge, United Kingdom. 4. Department of Allergy and Clinical Immunology, Royal Surrey County Hospital, Guildford, United Kingdom. 5. Department of Allergy, Broadgreen Hospital, Liverpool, United Kingdom. 6. Department of Allergy, Broadgreen Hospital, Liverpool, United Kingdom; Liverpool Hope University, Liverpool, United Kingdom. 7. Department of Allergy, Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom.
Abstract
BACKGROUND: Omega-5 gliadin allergy (also known as wheat-dependent exercise-induced anaphylaxis) is a rare allergy to wheat that often presents with intermittent severe anaphylaxis in the context of a cofactor, such as exercise. OBJECTIVE: To undertake a detailed clinical characterization of the largest cohort of patients with omega-5 gliadin allergy to date. METHODS: We retrospectively analyzed the demographic characteristics, presentation, investigation, and management of 132 patients presenting with omega-5 gliadin allergy in 4 UK centers. RESULTS: There were significant delays in diagnosis of 1 to 5 years (40% of patients) and more than 5 years (29% of patients). The commonest cofactors were exercise (80%), alcohol (25%), and nonsteroidal anti-inflammatory drugs (9%). A minority of patients (11%) had no identifiable cofactor. The level of specific IgE to omega-5 gliadin does not predict the severity of allergic reactions. Patients who adhered to a gluten-free diet and those who avoided wheat in combination with exercise achieved the largest reductions in subsequent allergic reactions of 67% and 69%, respectively. CONCLUSION: Omega-5 gliadin allergy is a rare wheat allergy that presents with severe anaphylaxis. The diagnosis is frequently delayed, and therefore we recommend that all adult patients presenting with anaphylaxis of unclear cause should have omega-5 gliadin specific IgE tested. A gluten-free diet or avoidance of wheat-based meals in combination with exercise (if the cofactor is exercise) helps to significantly decrease the risk of future allergic reactions. However, antihistamines and an epinephrine autoinjector must always be prescribed because one-third of patients continue to have allergic reactions despite dietary advice.
BACKGROUND:Omega-5 gliadinallergy (also known as wheat-dependent exercise-induced anaphylaxis) is a rare allergy to wheat that often presents with intermittent severe anaphylaxis in the context of a cofactor, such as exercise. OBJECTIVE: To undertake a detailed clinical characterization of the largest cohort of patients with omega-5 gliadinallergy to date. METHODS: We retrospectively analyzed the demographic characteristics, presentation, investigation, and management of 132 patients presenting with omega-5 gliadinallergy in 4 UK centers. RESULTS: There were significant delays in diagnosis of 1 to 5 years (40% of patients) and more than 5 years (29% of patients). The commonest cofactors were exercise (80%), alcohol (25%), and nonsteroidal anti-inflammatory drugs (9%). A minority of patients (11%) had no identifiable cofactor. The level of specific IgE to omega-5 gliadin does not predict the severity of allergic reactions. Patients who adhered to a gluten-free diet and those who avoided wheat in combination with exercise achieved the largest reductions in subsequent allergic reactions of 67% and 69%, respectively. CONCLUSION:Omega-5 gliadinallergy is a rare wheatallergy that presents with severe anaphylaxis. The diagnosis is frequently delayed, and therefore we recommend that all adult patients presenting with anaphylaxis of unclear cause should have omega-5 gliadin specific IgE tested. A gluten-free diet or avoidance of wheat-based meals in combination with exercise (if the cofactor is exercise) helps to significantly decrease the risk of future allergic reactions. However, antihistamines and an epinephrine autoinjector must always be prescribed because one-third of patients continue to have allergic reactions despite dietary advice.