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Antigen-specific IgG antibodies in feather duvet lung
Dirk Koschel1, Lars Lützkendorf, Bärbel Wiedemann
1Department of Pulmonary Diseases, Fachkrankenhaus Coswig, Centre for Pulmonary Diseases and Thoracic Surgery, Coswig, Germany. dr.koschel@fachkrankenhaus-coswig.de
Background:
Feather duvet lung (FDL) is a rare subgroup of bird fancier's lung (BFL). We were interested in determining antigen-specific IgG antibodies in patients with FDL and comparing them with those with BFL.
Material And Methods:
Specific IgG antibodies against goose and duck feathers, analysed with an automated fluorimetric enzyme immunoassay, were measured in healthy subjects (group A, n = 30), in patients with FDL (group B, n = 10) and with BFL (group C, n = 35); typical specific IgG antibodies of BFL in groups B and C.
Results:
An optimal threshold value for antibodies against goose or duck feathers to differentiate patients with either BFL or FDL from healthy subjects was determined at 10.85 mg L(-1) for goose feathers and at 8.81 mg L(-1) for duck feathers, respectively. Specific IgG antibodies against goose feathers were significantly higher in group B compared with group C. A ratio of specific IgG antibodies against goose feathers and budgerigar antigens with a threshold value of 0.91 could discriminate between patients with FDL and BFL with a specificity of 97% and a sensitivity of 90%.
Conclusions:
We were able to demonstrate the significant difference in IgG antibodies in patients with FDL and BFL and their contribution to discriminate between these similar kinds of extrinsic allergic alveolitis.
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