ADULT-ONSET WHEAT ANAPHYLAXIS IN THE POSTPARTUM PERIOD

Abstract

Introduction Although most food allergies present in childhood, food allergies can develop at any age. The lay press suggests the occurrence of new allergy following parturition, but this has not been well-documented in the literature. Case Description 37-year old female without prior food allergies presented with sudden-onset urticaria, one week postpartum, which resolved with epinephrine. Over the subsequent two weeks, she had two episodes of anaphylaxis, during walks preceded by wheat ingestion. Per the patient's report, ingestion of wheat without exercise did not provoke symptoms. Skin testing shortly thereafter to a panel of aeroallergens and food allergens was negative. Serum specific IgE testing and component-resolved diagnostics were significant only for wheat omega-5 gliadin (5.3 ISU-E). An open challenge to wheat was positive with urticaria. We recommended strict avoidance of wheat. On follow up in 4 years, she had had no further allergic reactions and continued to avoid wheat. Omega-5 gliadin sensitization has declined slightly over these four years, to 2.1 ISU-E. She has not been re-challenged to wheat. Discussion Recent anaphylaxis may yield falsely-negative skin test results. This patient's initial history was suggestive of food-dependent, exercise-induced anaphylaxis (FDEIA). Wheat sensitization, specifically omega-5 gliadin, is the most commonly reported sensitization and trigger in FDEIA. Although exercise was a previously required component of her reactions, our patient developed subsequently a reaction during the open challenge, which was at rest. Striking in this case was the development of new food allergy closely associated with parturition. Pregnancy could modify food allergy risk.