Related Experiment Videos
Induced sputum, eosinophilic bronchitis, and chronic obstructive pulmonary disease
1Asthma Research Group, Departments of Medicine and Paediatrics, St. Joseph's Hospital and McMaster University, Hamilton, Ontario, Canada.
American Journal of Respiratory and Critical Care Medicine
|November 11, 1999
Summary
Induced sputum analysis reveals eosinophilic bronchitis, common in asthma, can occur in COPD and chronic cough. This finding is crucial as eosinophilia indicates response to corticosteroid treatment.
Area of Science:
- Pulmonology
- Allergy and Immunology
- Respiratory Medicine
Background:
- Sputum induction and examination allow for analysis of cellular and molecular markers of airway inflammation in various respiratory conditions.
- These methods are safe, non-invasive, reproducible, valid, and responsive to treatment, even in severe asthma and COPD exacerbations.
Purpose of the Study:
- To explore the role of sputum eosinophilia in diagnosing and managing airway inflammatory diseases.
- To investigate the occurrence and clinical significance of eosinophilic bronchitis in patients with asthma, chronic cough, and COPD.
Main Methods:
- Utilizing induced sputum analysis to identify cell and molecular markers of airway inflammation.
- Correlating sputum findings, specifically eosinophilia, with clinical diagnoses and treatment responses.
Main Results:
- Eosinophilic bronchitis, characterized by sputum eosinophilia, is typical in asthma but also observed in some patients with chronic cough and COPD.
- While eosinophilia in COPD is often linked to smoking, other causes may exist.
- The presence of sputum eosinophilia generally predicts a positive response to corticosteroid therapy.
Conclusions:
- Induced sputum examination is a valuable tool for assessing airway inflammation in diverse respiratory diseases.
- Eosinophilic bronchitis, identified via sputum eosinophilia, is a clinically important phenotype that responds to corticosteroids.
- Absence of sputum eosinophilia may be associated with corticosteroid resistance in certain airway diseases.