Asthma and lower airway diseaseBiomarker surrogates do not accurately predict sputum eosinophil and neutrophil percentages in asthmatic subjects
Section snippets
Methods
Subjects with mild-to-severe asthma were comprehensively characterized according to the Severe Asthma Research Program (SARP) phenotype protocol at Wake Forest School of Medicine, as previously described.37 Briefly, nonsmoking subjects (<5 pack years) who met American Thoracic Society criteria for the diagnosis of asthma (enriched for severe asthma) provided informed consent (Wake Forest Institutional Review Board–approved protocol, BG01-425). Evaluation included spirometry, bronchodilator
Subjects' demographics
There were significant differences in lung function, bronchodilator reversibility, symptoms, and health care use for subjects with severe asthma compared with those with mild and moderate asthma (Table I). Age and duration of asthma were increased in subjects with more severe asthma, but there were no differences in atopic measures, including total serum IgE levels, frequency of positive skin test results, number of positive skin test results, serum eosinophil counts, or Feno levels.
Subjects
Discussion
Sputum eosinophilia and neutrophilia are characteristics of bronchial inflammation in asthmatic patients, reflect underlying airway pathology, and are useful in predicting responses to therapeutic interventions.3, 7, 8, 9, 10, 11, 12 Investigators have explored alternative biomarkers as surrogates because of the time-intensive and technically demanding methods for sputum induction, processing, and analysis in clinical settings. The potential usefulness of readily available predictive biomarkers
References (61)
- et al.
Clinical assessment of asthma severity partially corresponds to sputum eosinophilic airway inflammation
Respir Med
(2004) - et al.
Airway inflammation assessed by invasive and noninvasive means in severe asthma: eosinophilic and noneosinophilic phenotypes
J Allergy Clin Immunol
(2006) - et al.
Sputum eosinophil counts predict asthma control after discontinuation of inhaled corticosteroids
J Allergy Clin Immunol
(2005) - et al.
Loss of control of asthma following inhaled corticosteroid withdrawal is associated with increased sputum interleukin-8 and neutrophils
Chest
(2007) - et al.
Clinical usefulness of fractional exhaled nitric oxide for diagnosing prolonged cough
Respir Med
(2008) - et al.
Exhaled nitric oxide and exhaled breath condensate pH in severe refractory asthma
Chest
(2010) - et al.
Nitric oxide in exhaled breath is poorly correlated to sputum eosinophils in patients with prednisone-dependent asthma
J Allergy Clin Immunol
(2010) - et al.
Relationship between airway inflammation, hyperresponsiveness, and obstruction in asthma
J Allergy Clin Immunol
(2001) - et al.
The influence of age on induced sputum differential cell counts in normal subjects
Chest
(2004) - et al.
Expiratory flows and airway inflammation in elderly asthmatic patients
Respir Med
(2011)
Association of forced expiratory volume with disease duration and sputum neutrophils in chronic asthma
Am J Med
Characterization of the Severe Asthma Phenotype by the NHLBI Severe Asthma Research Program
J Allergy Clin Immunol
Exhaled nitric oxide identifies the persistent eosinophilic phenotype in severe refractory asthma
J Allergy Clin Immunol
A comparison of exhaled nitric oxide and induced sputum as markers of airway inflammation
J Allergy Clin Immunol
Exhaled nitric oxide in pulmonary diseases. A comprehensive review
Chest
Asthma exacerbations and sputum eosinophil counts: a randomised controlled trial
Lancet
A trial of clarithromycin for the treatment of suboptimally controlled asthma
J Allergy Clin Immunol
Evidence that severe asthma can be divided pathologically into two inflammatory subtypes with distinct physiologic and clinical characteristics
Am J Respir Crit Care Med
Neutrophilic inflammation in severe persistent asthma
Am J Respir Crit Care Med
Analysis of induced sputum in adults with asthma: identification of subgroup with isolated sputum neutrophilia and poor response to inhaled corticosteroids
Thorax
Analyses of asthma severity phenotypes and inflammatory proteins in subjects stratified by sputum granulocytes
J Allergy Clin Immunol
Changes in sputum eosinophils predict loss of asthma control
Am J Respir Crit Care Med
Determining asthma treatment by monitoring sputum cell counts: effect on exacerbations
Eur Respir J
“Refractory” eosinophilic airway inflammation in severe asthma. Effect of parenteral corticosteroids
Am J Respir Crit Care Med
Mepolizumab for prednisone-dependent asthma with sputum eosinophilia
N Engl J Med
Lebrikizumab treatment in adults with asthma
N Engl J Med
Can we predict sputum eosinophilia from clinical assessment in patients referred to an adult asthma clinic?
Intern Med J
Correlation between exhaled nitric oxide, sputum eosinophils, and methacholine responsiveness in patients with mild asthma
Thorax
The use of exhaled nitric oxide concentration to identify eosinophilic airway inflammation: an observational study in adults with asthma
Clin Exp Allergy
Asthma morbidity among inner-city adolescents receiving guidelines-based therapy: role of predictors in the setting of high adherence
J Allergy Clin Immunol
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Supported by the National Heart, Lung, and Blood Institute Severe Asthma Research Program Awards HL69167, U10HL109164, and RC2HL101487.
Disclosure of potential conflict of interest: A. T. Hastie, W. C. Moore, B. M Rector, and D. A. Meyers have received grants from the National Heart, Lung, and Blood Institute (NHLBI). R. M. Pascual has consultant arrangements with United Therapeutics and has received grants from Actelion. S. P. Peters has received a grant and travel support from the National Institutes of Health (NIH)/NHLBI; has served on advisory boards for AstraZeneca, Aerocrine, Merck, Targacept, and TEVA; has received payment for lectures from Merck and Integrity CE; and has received royalties from UpToDate. E. R. Bleecker has received grants and travel support from the NIH/NHLBI. The rest of the authors declare that they have no relevant conflicts of interest.