Allergy to egg yolk possibly induced by sensitization to bird serum antigens.

Hypersensitivity to ingested hen's egg yolk is described in a 65-year-old female patient. The patient's symptoms started in adult life and coincided with the acquisition of a parrot as a household pet. The bird's presence caused complaints of allergic rhinitis, while the ingestion of eggs caused urticaria and angioedema. Analysis of sequential blood serum samples revealed high levels of IgE antibodies to egg yolk and to various bird sera, but no precipitins. RAST-inhibition experiments indicated that the primary sensitization may have been to antigens from the parrot.