Latin name: Melopsittacus undulatus
Source material: Feathers
Common names: Budgerigar, Budgie, Parakeet
Direct or indirect contact with bird allergens may cause sensitisation. Bird allergens may be major components of house dust.
Budgerigar and Parakeet are the common names for a widespread group of small Parrots, native to the Indo-Malayan-Australian region and now the most popular cage birds in the world. Parakeets have long, pointed tails, unlike the chunky Lovebirds with which they are sometimes confused. The wild Budgerigar of Australia is usually green or blue with black and yellow markings; as a cage bird, however, it has been bred in many color varieties.
Large flocks, sometimes in the tens of thousands, inhabit the open grasslands in central Australia, nesting in the spring and summer in the southern areas of the continent. In most of the world, however, Budgerigars are familiar only as pets.
Well-defined major allergenic bands with molecular mass of 20-30 kDa and 67 kDa have been detected and identified in IgE immunoblots with feather extracts as well as with serum proteins of Budgerigar, Parrot, Pigeon, Canary, and Hen. Inhalable feather dust was shown to contain several allergenic components which cross-react with serum allergens/antigens of the same as well as of other bird species (1).
The allergens have not been fully characterised yet.
As noted above, inhalable feather dust contains several allergenic components which cross-react with serum allergens/antigens of the same as well as of other bird species (1).
Cross-reactivity between Chicken and other phylogenetically related bird species may be expected, and in Chicken-allergic patients significant IgE antibody titers to Parrot, Budgerigar, Chicken, Pigeon, Goose and Duck have been reported (2-3, even in patients without known exposure (1).
Budgerigar and Hen feather and egg yolk alpha-livetin have been shown to have common epitopes, and the authors of the study suggest that alpha-livetin (Chicken serum albumin) leads to a cross-sensitisation and consequently to Bird-Egg Syndrome (4).
Asthma, allergic rhinitis and allergic conjunctivitis may result on exposure to Budgerigars (5-6). The allergic manifestations may present as Bird Fancier´s Asthma and as the so-called Bird-Egg Syndrome, with symptoms such as rhinitis, urticaria and angioedema, and also as gastro-intestinal problems (3, 7).
In 212 sera from Budgerigar and Canary fanciers with symptoms of rhinitis and/or bronchial asthma, in 25 of 98 Canary feather-specific IgE antibody measurements, and in 28 of 154 Budgerigar feather-specific IgE antibody measurements, a significant level of specific IgE was found. In 3 sera, IgE antibodies against sera from both birds were present. IgE antibodies against Canary and/or Budgerigar feathers were present in about 20% of Canary and Budgerigar fanciers with symptoms of atopic disease. Canary and Budgerigar feathers contain IgE-binding antigens that are not present in the corresponding bird sera and droppings (6).
In a prospective study, 258 adults were investigated for sensitisation against bird antigens (Budgerigar, Canary, Pigeon) using an intracutaneous test. Eighteen of 78 Budgerigar keepers reacted against Budgerigar feathers. Thirty (38%) showed a positive skin reaction with at least 1 of the 3 extracts tested. In persons not exposed to birds, 18/96 (19%) were found to react to at least 1 of the 3 allergen extracts. Late reactions occurred in 5/70 (7%) Budgerigar keepers. The frequency of sensitisation against Budgerigar antigens increased to 48% of bird keepers (24/50) if the birds could fly around in their homes instead of being always caged (4/22, 18%). Three of the 78 Budgerigar keepers (4%) had a positive nasal provocation with feather extract, and they were skin-positive against all 3 bird antigens tested (7).
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 disease occurs after exposure to organic dust, especially after close contact with Pigeons or other birds such as Budgerigars, Parrots, Canaries, Parakeets, Cockatiels, Doves or Finches. Exposure results in the development of immunoglobulins including IgE (1), IgM (8), IgA and various IgG subclasses (9-11). The antibodies may be found in the sera and saliva of patients (12) as well as in the sera of asymptomatic but exposed subjects (13).
The allergenic proteins may be found in bird serum, droppings, skin scales, feathers and, in the case of Pigeons, Pigeon bloom (a waxy fine dust which coats the feathers of Pigeons). Contact may result from handling birds, cleaning their lofts, or exposure to the organic dust drifting down from a ceiling or roof where birds nest.
Diagnosis is based on a characteristic clinical picture and a typical x-ray pattern, accompanied by the presence of specific IgG antibodies (14).
The measurement of specific IgG using IgG tracer technology has been shown to be a sensitive and specific assay for the routine diagnostic testing of extrinsic allergic alveolitis (15).
Feather Mites are a major source of soluble proteins derived from feathers, accounting for up to 10% of the total weight of the feather. RAST inhibition indicated feather Mites had species-specific epitopes as well as ones that cross-reacted with Dermatophagoides pteronyssinus (16-17).
- Tauer-Reich I, Fruhmann G, Czuppon AB, Baur X. Allergens causing bird fancier's asthma. Allergy 1994;49(6):448-53
- de Maat-Bleeker F, van Dijk AG, Berrens L. Allergy to egg yolk possibly induced by sensitization to bird serum antigens. Annals of Allergy 1985;54(3):245-8.
- van Toorenenbergen AW, Huijskes-Heins MI, Gerth van Wijk R. Different pattern of IgE binding to chicken egg yolk between patients with inhalant allergy to birds and food-allergic children. Int Arch Allergy Immunol 1994;104(2):199-203.
- Szepfalusi Z, Ebner C, Pandjaitan R, Orlicek F, Scheiner O, Boltz-Nitulescu G, Kraft D, Ebner H. Egg yolk alpha-livetin (chicken serum albumin) is a cross-reactive allergen in the bird-egg syndrome. J Allergy Clin Immunol 1994;93(5):932-42
- Gerth Van Wijk R, Van Toorenenbergen AW, Dieges PH. Nasal allergy to avian antigens. Clin Allergy 1987;17(6):515-21
- van Toorenenbergen AW, Gerth van Wijk R, van Dooremalen G, Dieges PH. Immunoglobulin E antibodies against budgerigar and canary feathers. Int Arch Allergy Appl Immunol 1985;77(4):433-7
- Bosenecker A, Musken H, Bergmann KC. Sensitization in budgerigar owners. [German] Pneumologie 1998;52(4):209-13
- Martinez-Cordero E, Aquilar Leon DE, Retana VN. IgM antiavian antibodies in sera from patients with pigeon breeder’s disease. J Clin Lab Anal 2000:14(5):201-7
- Yoshizawa Y, Miyashita Y, Inoue T, Sumi Y, Miyazaki Y, Sato T, et al. Sequential evaluation of clinical and immunological findings in hypersensitivity pneumonitis: serial subclass distribution of antibodies. Clin immunol Immunopathol 1994;73(3):330-7
- Todd A, Coan R, Allen A. Pigeon breeder’s lung; IgG subclasses to pigeon Intestinal mucin and IgA antigens. Clin Exp Immunol 1993;92(3):494-9
- Baldwin CI, Todd A, Bourke SJ, Allen A, Calvert JE. IgG subclass responses to pigeon intestinal mucin are related to development of pigeon fancier’s lung. Clin Exp Allergy 1998;28(3):349-57
- McSharry C, Macleod K, McGregor S, Speekenbrink AB, Sriram S, Boyd F, et al. Mucosal immunity in extrinsic allergic alveolitis: salivary immunoglobulins and antibody against inhaled avian antigens among pigeon breeders. Clin Exp Allergy 1999;29(7):957-64
- Rodrigo MJ, Benavent MI, Cruz MJ, Rosell M, Murio C, Pascual C, et al. Detection of specific antibodies to pigeon serum and bloom antigens by enzyme linked immunosorbent assay in pigeon breeder’s disease. Occup Environ Med 2000;57(3):159-64
- Rodriguez de Castro F, Carrillo T, Castillo R, Blanco C, Diaz F, Cuevas M. Relationship between characteristics of exposure to pigeon antigens. Clinical manifestations and humoral immune response. Chest 1993;103(4):1059-63
- Lopata A, Schinkel M, Andersson C, Johansson G, van Hage-Hamsten M. Quantification of IgG antibodies to bird antigens in the diagnosis of extrinsic allergic alveolitis (EAA) using the UniCAP system. (Manuscript in preparation)
- Colloff MJ, Merrett TG, Merrett J, McSharry C, Boyd G. Feather mites are potentially an important source of allergens for pigeon and budgerigar keepers. Clin Exp Allergy 1997;27(1):60-7
- Merrett TG, Colloff M, McSharry C, Merret J. Feather mite specific IgE antibodies are commonly found among pigeon keepers. Ann Allergy 1993;70:65