Background: Although both inhaled and oral corticosteroids have anti-inflammatory effects causing improvement in clinical symptoms and spirometry in the treatment of asthma, the role of corticosteroids in the management of chronic obstructive pulmonary disease (COPD) is controversial. Objective: To evaluate the effects of inhaled corticosteroids on sputum neutrophilia in clinically stable COPD patients. Methods: In total, 18 patients were enrolled in the study. During 2 months, 9 patients in group A inhaled fluticasone propionate (FP) 500 mu g 3 times daily. In group B 9 patients received placebo. All of the patients continued to inhale both salbutamol and ipratropium bromide. In 9 patients, sustained-released theophylline was also administered. Blood samples, spirometric tests, blood gas analyses, and either spontaneous or induced sputum cultures were evaluated on entry into the study, after a 2 months of treatment and following the 6-week washout period. Results: After the 2-month FP treatment, no significant changes in the number of peripheral blood neutrophils, blood gas and spirometry data were observed in both groups. In group A, the total cell number and the number of neutrophils decreased from a mean of 3.4 +/- 1.3 x 10(6) cells/g and 0.6 +/- 0.3 x 10(6) neutrophils/g on entry into study to 1.9 +/- 0.6 x 10(6) cells/g and 0.02 +/- 0.01 x 10(6) neutrophils/g after 8-week treatment with FP, returning to 3.3 +/- 1.1 x 10(6) cells/g and 0.5 +/- 0.3 x 10(6) neutrophils/g following the washout period. The percentages of neutrophils were 55.6 and 77.9% in groups A and B after 2 months of FP treatment. There was no significant change in group B values during the study. Conclusion: These data suggest that neutrophilic inflammation in sputum may be decreased by inhaled corticosteroids in clinically stable COPD patients. Copyright (C) 2000 S. Karger AG, Basel.