Abstract
Background: Spirometry is the standard test to monitor patients with pulmonary pathologies. Sputum rheology has recently emerged as a possible biomarker of obstructive respiratory diseases in which difficulties to expectorate are related to a thickened mucus.
Objective: To compare rheometry and spirometry tests as pathological markers.
Methods: Healthy volunteers (HV), COPD, asthmatic, and stable CF patients (n = 11, 11, 12, 11) were tested with spirometry (FEV1, FVC, and PEF), before and after administering Beta2-adrenergic agonist. Sputum samples were also collected, and tested with oscillatory rheometry, yielding the sputum elastic and viscous moduli, G’ and G”. Under small deformations (< 5%), the sputum behaves as a soft solid (G’ > G”).
Results: Expectedly, spirometry tests show the degraded pulmonary function of CF patients, but only FEV1 distinguishes the four populations with some overlap. The effect of Beta2-adrenergic agonist treatment is very weak. Rheology measurements more clearly distinguish HV, COPD, and CF patients, with a weaker population overlap.
Conclusion: As expected, spirometry consistently allows to quantify a loss of pulmonary capacity in respiratory diseases. Sputum rheology offers a complementary marker of the patient condition with strong variations observed, at least for CF and COPD, which suggests its potential to monitor more finely the patient’s evolution.
Footnotes
Cite this article as: European Respiratory Journal 2019; 54: Suppl. 63, PA1709.
This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).
- Copyright ©the authors 2019