Induced Sputum: A Valuable Tool for Assessing Cellular and Microbiological Characteristics in Cystic Fibrosis Expectorating Teenagers
M. Guedes, D. Frankel, S. A. Baron, J. Berbis, N. Stremler‐Le Bel, M. Baravalle‐Einaudi, P. Roll, E. Kaspi, J. C. DubusABSTRACT
Introduction
Cellular characteristics of induced sputum (IS) are not investigated in cystic fibrosis (CF) patients.
Objectives
This pilot study, conducted on 17 expectorating CF adolescents, compared sputa obtained the same day, in a stable period, by autogenic drainage (expectorating sputum, ES) and 4 h later after inhaling hypertonic saline (IS).
Results
No difference was noted concerning weight, volume, and percentage of dead cells between the two collection methods. Sample quality (< 50% of dead cells and < 20% squamous cells) was higher in the case of IS than ES (94.1% vs. 58.8%, p = 0.03), with a doubled cell count (p = 0.01), a higher proportion of alveolar macrophages (p = 0.03), and a lower proportion of squamous cells (p = 0.004). The detection of germs increased by 44% in IS samples, possibly modifying therapeutic management in 17.6% of the patients.
Conclusion
IS improves the quality and the microbiological detection of the sample, even among CF patients who spontaneously expectorate.