[Analysis of induced sputum in refractory asthma].
Induction of sputum by inhalation of hypertonic or isotonic fluid makes possible the safe and noninvasive harvesting of airway cells from patients with asthma, regardless of disease severity. Analysis of sputum cells has helped to identify different phenotypes of refractory asthma and shown that such asthma can be eosinophilic, neutrophilic, or both. Elevated eosinophil levels in sputum indicate a risk of exacerbation if the corticosteroid dose is reduced in stabilized patients. Surveillance of eosinophilia levels as an indicator for corticosteroid adjustment in refractory asthma makes it possible to reduce the frequency of severe exacerbations.
Louis
Renaud
R
Service de pneumologie, CHU Sart-Tilman, Liège BE-4000, Belgique. R.Louis@chu.ilg.ac.be
Potmans
Vincent
V
D001249:Asthma / Q000188:drug therapy; D006801:Humans; D013183:Sputum / Q000166:cytology*; D017211:Treatment Failure