[Comparative study of secretory IgA].

Objective: The aim of this study was measure and compare Secretory IgA levels in the respiratory tract.

Design: Cross-sectional study.

Setting: Neumology Department of General Hospital. La Raza Medical Center Mexico.

Material And Method: There were 35 volunteers. Samples of sputum, washings nasopharyngeal and bronchial was obtained from thirty five patients with COPD. Measurement of SIgA levels was performed by nephelometric technique. Results is reported as ratio of SIgA concentration/Total proteins concentration named SIgA relative concentration. Correlation index was obtained of three type of samples.

Results: The SIgA values of sputum, washings nasopharyngeal and bronchial was similar similar +/- 0.011, 0.064 +/- 0.007 and 0.082 +/- 0.017 respectively). Multiple correlation was r = 0.508 (p < 0.01).