Comparison of three methods for the determination of serum alpha-1-antitrypsin in patients with pulmonary diseases.
In patients with pulmonary diseases, serum alpha 1-antitrypsin (AAT) was measured by three methods: radial immunodiffusion (RID), trypsin inhibitory capacity assay (TIC) and by rate nephelometry with the immunosystem (NIA) in a total of 369 subjects (sarcoidosis, n = 35; asthma, n = 41; chronic obstructive bronchitis, n = 62; bronchogenic carcinoma, n = 93; pneumonia, n = 24; tuberculosis, n = 43; fibrosis, n = 22; healthy controls, n = 49). Considering all patients, AAT was found to be significantly elevated (p less than 0.01-0.001) in all methods (RID: 3.3 +/- 1.0 g/l; TIC: 2.7 +/- 0.4 g/l; NIA: 2.1 +/- 0.8 g/l) compared to healthy controls (RID: 2.1 +/- 0.3 g/l; TIC: 2.1 +/- 0.4 g/l; NIA: 1.2 +/- 0.3 g/l). The lowest mean values were found by means of the NIA method. The best correlation coefficient (R) was evaluated between the TIC and the NIA method (R = 0.96) in healthy controls, but the best correlated methods were the RID and the NIA (R = 0.93) in patients with pulmonary disease.
Prinsen
J H
JH
Department of Clinical Chemistry, Marienhospital Gelsenkirchen, University of Essen, FRG.
Schweisfurth
H
H
Rasche
B
B
Breuer
J
J
D000328:Adult; D000368:Aged; D002648:Child; D005260:Female; D006801:Humans; D005779:Immunodiffusion; D008171:Lung Diseases / Q000097:blood*; D008297:Male; D008722:Methods; D008875:Middle Aged; D000515:alpha 1-Antitrypsin / Q000032:analysis*
D000515:alpha 1-Antitrypsin