D3.280 - Severe Anaphylaxis Induced by Turkey Egg with Tolerance to Hen’s Egg and Poultry Meat: A First Report

Food allergy to hen’s egg is well recognized and extensively studied; however, allergic reactions to eggs from other avian species are exceedingly rare. While poultry meat allergy has been described in association with hen’s or turkey meat proteins, isolated egg allergy restricted to a single avian species is scarcely reported. Component-resolved diagnostics are available for hen’s egg allergens but not for turkey egg, which limits mechanistic interpretation in such cases.

To the best of our knowledge, this is the first reported case of severe anaphylaxis induced by turkey egg, affecting both raw and cooked forms, in a patient who tolerates hen’s egg in both raw and cooked forms as well as poultry meat.

A 28-year-old male with no known chronic disease, atopic disorder, or previous history of food allergy was referred to our allergy clinic following a life-threatening allergic reaction. Two months prior to presentation, the patient experienced an acute reaction approximately 20 minutes after consuming a mixed meal containing baked turkey egg. He developed rapidly progressive shortness of breath, throat tightness, and dysphonia, accompanied by facial flushing and generalized erythema. On admission to the emergency department, he was found to be hypotensive (blood pressure 70/40 mmHg) with oxygen desaturation. Physical examination revealed marked oropharyngeal edema, including uvular swelling. Due to respiratory compromise, the patient required endotracheal intubation and was admitted to the intensive care unit, where he remained intubated and mechanically ventilated for one day. The patient clearly stated that he had never consumed turkey egg before this episode. Importantly, following the index reaction, he continued to consume hen’s egg (both raw and cooked forms) as well as hen’s meat without any symptoms, confirming ongoing tolerance. Prick-to-prick skin testing with fresh turkey egg white and yolk was performed. As early as the third minute after testing, the patient developed generalized pruritus, erythema extending beyond the test sites, diffuse flushing, shortness of breath, and hypotension (blood pressure 90/60 mmHg). Immediate treatment with 0.5 mg intramuscular epinephrine was administered. The local skin reaction was pronounced, with a wheal size of 40 × 32 mm for egg white and 30 × 18 mm for egg yolk (Figure 1). A detailed dietary history revealed that the patient regularly consumed hen’s egg in both raw and cooked forms, as well as hen’s meat, without any symptoms. Serum-specific IgE testing demonstrated sensitization to hen’s egg white (44.8 kUA/L), hen’s egg yolk (34.6 kUA/L), and hen’s meat (6.16 kUA/L), despite clear clinical tolerance. In contrast, serum-specific IgE to turkey meat was negative (<0.10 kUA/L), and an oral food challenge with turkey meat was subsequently performed and was tolerated without any adverse reaction. 

This case highlights a previously unrecognized phenotype of food-induced anaphylaxis characterized by isolated sensitization to turkey egg with preserved tolerance to hen’s egg and poultry meat.