Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2013 Apr;30(2):117-23.
doi: 10.4103/0970-2113.110419.

Usefulness of induced sputum eosinophil count to assess severity and treatment outcome in asthma patients

Ankan Bandyopadhyay  1 , Partha P Roy, Kaushik Saha, Semanti Chakraborty, Debraj Jash, Debabrata Saha
Affiliations

Usefulness of induced sputum eosinophil count to assess severity and treatment outcome in asthma patients

Ankan Bandyopadhyay et al. Lung India. 2013 Apr.

Abstract

Context: Currently treatment decisions in asthma are governed by clinical assessment and spirometry. Sputum eosinophil, being a marker of airway inflammation, can serve as a tool for assessing severity and response to treatment in asthma patients.

Aims: To establish correlation between change in sputum eosinophil count and forced expiratory volume in one second (FEV1)% predicted value of asthma patients in response to treatment. In this study, we also predicted prognosis and treatment outcome of asthma patients from baseline sputum eosinophil count.

Settings and design: A longitudinal study was conducted to determine the treatment outcome among newly diagnosed asthma patients who were classified into A (n = 80) and B (n = 80) groups on the basis of initial sputum eosinophil count (A ≥ 3% and B < 3%).

Materials and methods: After starting treatment according to Global Initiative for Asthma Guideline, both A and B groups were evaluated every 15 days interval for the 1(st) month and monthly thereafter for a total duration of 12 months. In each follow-up visit detailed history, induced sputum eosinophil count and spirometry were done to evaluate severity and treatment outcome.

Results: FEV1% predicted of group A asthma patients gradually increased and sputum eosinophil count gradually decreased on treatment. Longer time was required to achieve satisfactory improvement (FEV1% predicted) in asthma patients with sputum eosinophil count ≥3%. There was statistically significant negative correlation between FEV1% predicted and sputum eosinophil count (%) in of group A patients in each follow-up visit, with most significant negative correlation found in 8(th) visit (r = -0.9237 and P = < 0.001). Change in mean FEV1% (predicted) from baseline showed strong positive correlation (r = 0.976) with change in reduction of mean sputum eosinophil count at each follow-up visits in group A patients.

Conclusions: Sputum eosinophil count, being an excellent biomarker of airway inflammation, can serve as a useful marker to assess disease severity, treatment outcome, and prognosis in asthma patients.

Keywords: Asthma; forced expiratory volume in one second; induced sputum; sputum eosinophil count; treatment outcome.

PubMed Disclaimer

Conflict of interest statement

Conflict of Interest: None declared.

Figures

Figure 1
Figure 1
Flow chart describing the patient flow and study method
Figure 2
Figure 2
Line diagrams showing outcome variables (mean no. of sleep disturbances, performance of daily activity, control status, and no. of exacerbations) of group A and group B during initial and follow-up visits
Figure 3
Figure 3
(a) Line diagram showing sputum eosinophil count (%) of group A and group B during initial and follow-up visits. (b) Line diagram showing FEV1% predicted of group A and group B during initial and follow-up visits
Figure 4
Figure 4
Scatter plot showing correlation between changes in mean FEV1 (% predicted) and change in reduction of mean sputum eosinophil count (%) during follow-up visits in group A
See this image and copyright information in PMC

References

    1. Global initiative for asthma/Who initiative. [Last cited in 2010 June 29]. Available from: http://www.ginasthma.com/index.asp?l1= 1andl2 = 0 .
    1. Cianchetti S, Bacci E, Ruocco L, Bartoli ML, Ricci M, Pavia T, et al. Granulocyte markers in hypertonic and isotonic saline-induced sputum of asthmatic subjects. Eur Respir J. 2004;24:1018–24. - PubMed
    1. Nathan RA, Sorkness CA, Kosinski M, Schatz M, Li JT, Marcus P, et al. Development of the asthma control test: A survey for assessing asthma control. J Allergy Clin Immunol. 2004;113:59–65. - PubMed
    1. Kim CK, Koh YY, Callaway Z. The validity of induced sputum and bronchoalveolar lavage in childhood asthma. J Asthma. 2009;46:105–12. - PubMed
    1. Green RH, Brightling CE, McKenna S, Hargadon B, Parker D, Bradding P, et al. Asthma exacerbations and sputum eosinophil counts: A randomised controlled trial. Lancet. 2002;360:1715–21. - PubMed