Nasal and bronchoalveolar lavage fluid cytokines in early cystic fibrosis.

Cytokine levels in nasal and lower airways in young cystic fibrosis (CF) patients were compared with those in controls. Nasal (NLF) and bronchoalveolar (BALF) lavage fluids were obtained from children with or without CF who were undergoing bronchoscopy for clinical indications. In NLF, neither inflammatory cells nor cytokine concentrations differed between patients and controls. However, interleukin (IL)-8 levels in infected BALF from children with CF were markedly elevated compared with levels in infected and uninfected controls, even after standardization of IL-8 concentrations to bacterial counts. BALF IL-6 was modestly elevated in infected CF patients compared with uninfected but not infected controls; IL-10 did not differ among the groups. NLF and BALF IL-8 levels were not significantly correlated. Excessive airway inflammation in early CF thus appears to be confined to the lower respiratory tract, and IL-8 levels are markedly increased in children with CF compared with control children with a bacterial infection of the lower airways.