engleski

Induced sputum - a method for cytologic analysis of bronchial specimens

Sputum induction by inhalation of hypertonic saline is a noninvasive method to obtain secretions from the lower respiratory tract for cell counting and bacteriologic analyses. The aim of this study was to introduce the method of induced sputum in our clinical practice and to get an insight into airway inflammation by examining cell count differences in 15 asthmatic patients, 30 chronic obstructive pulmonary disease (COPD) patients and 15 healthy controls. Gradually increasing concentrations (3%, 4%, 5%) of hypertonic saline were inhaled. Subjects were encouraged to cough in order to expectorate. The quality of the sample was scored on the volume of the plugs (considered to represent lower respiratory tract secretion) and salivary contamination (proportion of squamous cdls in the slides). A sample score >4 was considered adequate, 3 intermediate, and 52 inadequate. Cytologic sputum analysis was done after microscopic selection of the plugs. The results showed that inhalation of hypersonic saline is a safe method to get adequate sample for investigating various inflammatory mechanisms in lower airways. There were differences in sputum from three groups of subjects, i.e. a higher proportion of neutrophils in COPD (32%) in comparison to asthmatics (15%) and healthy controls (10%). The percentage of alveolar macrophages also differed (COPD 56.5%, asthmatics 46%, healthy 40%). Asthmatic patients had a higher proportion of eosinophils (asthmatics 18.5%, COPD 1.9%, healthy 0.06%) and metachromatic cells (asthmatics 0.3%, COPD 0.039%, healthy 0.014%).

Sputum; cytology: Pulmonary disease-chronic obstructive disease; Asthma; diagnosis

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