Effects of short-term inhaled fluticasone on oxidative burst of sputum cells in cystic fibrosis patients

Inhaled corticosteroids have been proposed to decrease pulmonary inflammation in cystic fibrosis (CF). In this study the effects of therapy with inhaled fluticasone on clinical and sputum outcomes (leukocyte count, activity of myeloperoxidase, superoxide anion release) in adult CF patients were investigated in an open label design. Twenty-six stable patients (median+/-SD forced expiratory volume in one second (FEV1) 58.1+/-19.9% pred.) were randomly assigned to the study group (500 mu g b.i.d, for three weeks) or the control group (n=14; nonsteroid medication). Sputum samples were obtained during inhalation of hypertonic saline (3%, 20 min), which was found not to alter the investigated sputum parameters. No significant changes in clinical parameters, sputum leukocyte count, activity of myeloperoxidase, and baseline superoxide anion release where observed following therapy. Surprisingly, stimulated superoxide anion release increased significantly after therapy (34.1+/-17.7 versus 25.2+/-17.4 nmol.hr(-1).10(6) cells, p<0.03) and exceeded spontaneous variability of this parameter (p=0.02 versus control group). In conclusion, in adult cystic fibrosis patients short-term fluticasone therapy had no evident effect on clinical and sputum parameters. Further investigations are necessary to evaluate whether the observed up-regulation of oxidative capacity of inflammatory cells is of concern or benefit in these patients.