COMPARISON OF SAMPLES COLLECTED BY SPUTUM INDUCTION AND BRONCHOSCOPY FROM ASTHMATIC AND HEALTHY-SUBJECTS

To compare markers of inflammation in secretions obtained by sputum in duction (SI), bronchial wash (50 ml instillate [BW]), and bronchoalveo lar lavage (4 x 60 mi instillates [BAL]), we analyzed markers of infla mmation in samples obtained by these methods in 10 healthy and 10 asth matic subjects. Of the asthmatic subjects 8 had mild disease (FEV(1), % of predicted > 75%). Within subjects from both groups, we found that sputum, compared with either BW or BAL, had higher numbers of nonsqua mous cells (p = 0.0001) and higher levels of eosinophil cationic prote in (ECP) (p = 0.0001), albumin (p = 0.0001), and mucin-like glycoprote in (p = 0.0001). The eosinophil percentages and the ECP levels in sput um correlated more closely with those in BW (r = 0.67, p = 0.005; r = 0.69, p = 0.0008, respectively) than in BAL (r = 0.5, p = 0.03; r = 0. 37, p = 0.11). Comparing the asthmatic and healthy subgroups, we found that eosinophil percentages were higher in sputum (p = 0.0003) and BW (p = 0.006) from asthmatic subjects and that ECP levels were higher i n BW (p = 0.001) and BAL (p = 0.0005) from asthmatic subjects. We conc lude that analysis of induced sputum reveals information qualitatively similar to that obtained by analysis of BW and BAL and that sputum in duction is not only noninvasive and easily repeated but also yields sa mples more concentrated and richer in airway secretions than those obt ained by bronchoscopy.