Abstract

Introduction:

Airway obstruction and inflammation are char­acteristic features of asthma and COPD. Induced sputum may provide an alternative method in the investigation of airway inflammation.

Aim:

The aim of this study was to demonstrate and compare the relative proportion of the cells in induced sputum samples in patients with asthma and COPD.

Materials and Methods:

A group of 30 patients with mild to moderate asthma and a group of 20 patients moderate to severe COPD were studied. Spirometry with assessment of reversibility were recorded. Sputum was induced with inhala­tion of 3% hypertonic saline solution. Total and differential cell counts of sputum samples were determined.

Results:

Neutrophils were the predominant cells in the induced sputum samples of COPD patients and eosinophils were predominant in the samples from asthmatics. Induced sputum lymphocyte and macrophage counts were significantly higher in asthma than COPD.

Conclusions:

Increase in sputum neutrophils is characteristic of COPD patients, while an increase in eosinophils is found in asthma. Induced sputum procedure is a noninvasive, safe method for the determination of predominant cells of airway inflammation.