Study objectives: We examined the effects of
glucocorticoids on airway inflammation and its association with the
reversibility of airflow obstruction in response to oral glucocorticoid
administration in patients with COPD.
Twenty-four male patients with smoking-related stable pulmonary
emphysema without α1-antitrypsin deficiency and nine
normal healthy volunteers.
Measurements: We measured
the pulmonary function, the inflammatory cells, and the levels of
eosinophil cationic protein (ECP), immunoreactive neutrophil
elastase-α1-protease inhibitor (NE-α1-PI)
complex, and interleukin (IL)-8 in sputum induced from patients with
pulmonary emphysema in its stable phase before and after treatment with
20 mg oral prednisolone per day for 2 weeks.
The eosinophil and neutrophil counts and the concentrations of ECP,
NE-α1-PI complex, and IL-8 in the sputum were
significantly increased at baseline. The eosinophil count at baseline
was significantly correlated with the reversibility of airflow
obstruction following treatment, and the treatment also significantly
reduced the eosinophil numbers and ECP level in the sputum. In
contrast, the increased neutrophil number and the concentrations of
NE-α1-PI complex and IL-8 at baseline did not correlate
with the reversibility and were not affected by treatment.
Conclusions: These findings suggest that the eosinophilic
inflammation, not neutrophilic inflammation, in the airway is involved
in the reversible part of the airflow obstruction in response to
glucocorticoids in patients with pulmonary emphysema.
Abbreviations: BALF = BAL fluid;
ECP = eosinophil cationic protein;
NE-α1-PI = neutrophil