Bronchoalveolar lavage eosinophil cationic protein and interleukin-8 levels in acute asthma and acute bronchiolitis

Abstract

Objective: In this study, we measured the levels of eosinophil cationic protein (ECP) and interleukin (IL)-8 in bronchoalveolar lavage (BAL) fluid from patients with acute asthma and acute bronchiolitis, to determine any similarities or dissimilarities in the profiles of these biochemical markers in the two diseases. Methods: BAL fluids were obtained from children with acute asthma (n = 16), infants with acute bronchiolitis caused by respiratory syncytial virus (n = 18), and control subjects (n = 14). Children with asthma were selected to be free of viral infection. BAL cell counts and differentials were determined, and ECP and IL-8 levels were measured by radioimmunoassay and ELISA, respectively. Results: ECP levels in BAL fluids were significantly higher in the asthma group than in the bronchiolitis (P < 0.01) or control (P < 0.0001) groups. However, IL-8 levels were significantly higher in the bronchiolitis group than in the asthma (P < 0.01) or control (P < 0.001) groups. IL-8 levels in the asthma group and ECP levels in the bronchiolitis group were similar to those of the control group. Conclusion: This difference in profiles of ECP and IL-8 in acute asthma and acute bronchiolitis, together with a different inflammatory cell pattern, suggests that the nature of the inflammatory process within the lower respiratory tract may be distinctive in these two diseases. © 2005 Blackwell Publishing Ltd.