Application of Inflammatory Markers in Induced Sputum in Stable Chronic Obstructive Pulmonary Disease Patients with Positive Bronchodilation Tests

Positive bronchodilation (BD) tests can be noticed in some stable chronic obstructive pulmonary disease (COPD) patients.The characteristics of airway inflammation in this entity remain unclear.Our study aimed to identify the characteristics of airway inflammation in stable COPD patients with positive BD tests.The airway inflammation was assessed in 88 patients with stable COPD using the examination of induced sputum in the aftermath of lung function and BD tests.Cellular counts and the levels of molecular markers including eosinophil cationic protein (ECP),myeloperoxidase (MPO),interleukin-5 (IL-5),and IL-8 were assayed by Wright's stain,Immuno-CAP system,and ELISA,RT-PCR.Among the 88 patients with stable COPD,20 (22.7%) showed positive BD tests.The values of eosinophils (4.7%±3.4%) and ECP (90.1±41.6 ng/mL) in induced sputum in stable COPD patients with positive BD tests were markedly elevated as compared with those in stable COPD patients with negative BD tests or in healthy controls (all P<0.05),but significantly lower than those in asthmatic patients (all P<0.01).The IL-5 in sputum supernatant was significantly decreased in stable COPD patients with positive BD tests as compared with the patients with asthma (12.5±7.8 vs.48.2±26.0 ng/mL;P<0.01).However,healthy controls exhibited similar concentrations of IL-5 in induced sputum with patients with stable COPD,whether with positive or negative BD tests (all P>0.05).Moreover,the values of neutrophils (61.8%±15.1%),MPO (574.0±111.8 ng/mL),and IL-8 (32.6±13.4 ng/mL) in induced sputum in stable COPD patients with positive BD tests were significantly higher than those in asthmatics or normal controls (all P<0.01).However,the values of the above inflammatory markers in induced sputum were similar among stable COPD patients with positive or negative BD tests (all P>0.05).The stable COPD patients with positive BD tests may present not only eosinophilic airway inflammation but also neutrophilic airway inflammation.

Effects of Medication Use on Small Airway Function and Airway Inflammation in Patients with Clinically Controlled Asthma

Objective To observe effects of medication use on small airway function,airway inflammation and acute exacerbations in patients with clinically controlled asthma.Methods Forced expiratory flow over the middle half of the forced expiratory curve(FEF25%–75%),percentage of eosinophil,concentrations of eosinophil cationic protein(ECP)and interleukin(IL)-5 in induced sputum were assessed in patients with clinically controlled asthma who were given oral anti-inflammatory agents alone or in combination with inhaled therapy and inhaled therapy alone.Subsequently,acute exacerbations were compared between two groups during the 24-week follow-up period.Results FEF25%–75%in 43 patients with clinically controlled asthma given oral anti-inflammatory agents alone or in combination with inhaled therapy was significantly higher than that in 49 patients given inhaled therapy alone.Meanwhile,the percentage of eosinophils and levels of IL-5 and ECP in patients with clinically controlled asthma given oral anti-inflammatory agents alone or in combination with inhaled therapy were significantly lower than those in patients given inhaled therapy alone.Additionally,the patients with clinically controlled asthma given inhaled therapy were likely to have more acute exacerbation than the patients given oral anti-inflammatory agents alone or in combination with inhaled therapy during the 24-week follow-up period.Conclusion Systemic anti-inflammatory agents may have a greater effect on parameters reflecting small airway patency and reducing acute exacerbations,presumably secondary to reduction in airway inflammation.