IgE mediated reactions
Asthma, allergic rhinitis and allergic conjunctivitis may result following exposure to Duck feathers, epithelial cells or droppings. The allergic manifestations may present as Extrinsic Allergic Alveolitis (1).
Of 269 adult patients with suspected skin and respiratory allergies tested for feathers with skin specific IgE tests, 9% of the whole group and 14% of those positive to inhalant allergens were positive to any feather allergen. Two reacted to duck feathers, 12 to goose and 15 to chicken feathers. Symptoms were reported by 58% of feather skin specific IgE positive patients and 55% by other skin specific IgE positive patients. Positive RAST specific IgE tests were surprisingly few which may be explained by possible contamination of the skin extracts by mite allergens (2).
Extrinsic Allergic Alveolitis, also known as Hypersensitivity pneumonitis, 'Bird Fancier's Lung' and 'Farmer's Lung', is a disease of inflammation of the lung parenchyma in the terminal bronchioles and alveoli. Symptoms may start soon after exposure to bird allergens or after many years, and may include breathlessness, cough, occasional chills, and fever. Death may also result.
The allergenic proteins may be found in bird serum, droppings, and feathers. Contact may result from handling birds, cleaning their cages, or exposure to the organic dust drifting from where the birds reside.
Exposure to avian antigens results in the development of immunoglobulins including IgE (3), IgM (4), IgA and various IgG subclasses (5-7). The development of specific IgG and IgA antibodies to avian proteins does not necessarily indicate disease (8).
Diagnosis is based on a characteristic clinical picture and a typical x-ray pattern, accompanied by the presence of specific IgG antibodies (9).
Clinical allergy to commercial feather products is less common than usually thought, as a result of the removal of rough dry dust, washing and drying at 125OC. The allergens derived from unrefined feathers include bird serum proteins, bird droppings, and feather mites (2)
Polyester-filled pillows contain significantly more total weight of Der p 1 mite allergen (Dermatophagoides pteronyssinus) than feather-filled pillows (10).
