Use of co-immunoelectrodiffusion to detect presumed disease-associated precipitating antibodies, and time-course value of specific isotypes in bird-breeder's disease.
OBJECTIVE
The practical value of immunological diagnosis of bird-breeder's disease (BBD) is controversial, because of difficulties in distinguishing active disease patients from simple contact subjects. The aim of this study was to determine the diagnostic and prognostic value of (a) presumed disease-associated antibodies precipitating pigeon antigens (immunoglobulin A (IgAp) and P2 component), (b) characterization of specific isotypes (IgG, IgM, and IgA), and (c) antibody kinetics after antigen eradication.


METHODS
405 subjects (775 sera) in contact with birds were studied [by means of co-immunoelectrodiffusion (Co-IED) and enzyme-linked immunofiltration (ELIFA)] with soluble extracts of pigeon droppings and squab crop milk. These patients were divided into two groups based on the final clinical evaluation of the patients' physicians, which was taken as the gold standard (positive in 90 and negative in 315 cases).


RESULTS
On the basis of this gold standard, the detection of presumed disease-associated precipitating antibodies by Co-IED had a specificity of 95.5%, a sensitivity of 98.7%, an accuracy of 98%, and positive and negative predictive values of 95.5% and 98.7%, respectively. Most of the patients with a final positive diagnosis of BBD had specific IgG, IgM, and IgA antibodies by ELIFA. After antigen eradication, anti IgAp and/or P2 antibodies disappeared more rapidly than other precipitating systems.


CONCLUSIONS
Identification by Co-IED of precipitating immune complexes IgAp and/or P2 significantly reinforces the intrinsic credibility of immunological diagnosis of BBD. Compared to these presumed disease-associated precipitating antibodies, detection and time course of specific IgM, IgA antibodies, provided no additional diagnostic value or prognostic arguments to judge disease activity after antigen eradication.
Toubas
Dominique
D
Laboratoire de Parasitologie-Mycologie, CHU, Hôpital Maison Blanche, UPRES EA 2070, IFR 53 Biomolecules, Université de Reims Champagne-Ardenne, 45 rue Cognacq Jay, France.
Aubert
Dominique
D
Villena
Isabelle
I
Foudrinier
Frédérique
F
Chemla
Cathy
C
Pinon
Jean Michel
JM
D000368:Aged; D000485:Allergens; D000818:Animals; D000906:Antibodies / Q000097:blood*; D001716:Bird Fancier's Lung / Q000175:diagnosis / Q000276:immunology*; D016022:Case-Control Studies; D010856:Columbidae / Q000276:immunology; D005260:Female; D006386:Hemagglutination Tests; D006801:Humans; D005779:Immunodiffusion / Q000379:methods* / Q000706:statistics & numerical data; D007132:Immunoglobulin Isotypes / Q000097:blood; D007159:Immunologic Tests / Q000379:methods; D008297:Male; D008875:Middle Aged; D011233:Precipitin Tests; D011234:Precipitins / Q000097:blood; D011379:Prognosis; D012680:Sensitivity and Specificity
D000485:Allergens; D000906:Antibodies; D007132:Immunoglobulin Isotypes; D011234:Precipitins