Research Reports

Back to research reports

Sputum Biomarkers of Inflammation and Lung Function Decline in Children with Cystic Fibrosis

  • Researchers

    Scott D Sagel, Brandie D Wagner, Margaret M Anthony, Peggy Emmett and Edith T Zemanick

  • Place of research

    University of Colorado

  • Publication

    American Journal of Respiratory and Critical Care Medicine / November 2012

  • Subjects

    , , , , ,

  • We wanted to know whether measuring inflammation in sputum (mucus) samples from children with CF would be helpful to monitor lung disease activity or even predict those children at greater risk for experiencing more rapid lung function decline.

  • Why is this important?

    If it turns out that collecting sputum and measuring inflammation allows us to monitor lung disease activity, and possibly even predict those children at risk for faster lung function decline, this would have a significant impact on routine clinical practice in CF. It means that besides monitoring infection in sputum collected at routine clinic visits, that CF clinicians could also measure inflammation in these same samples and treat those children who have too much inflammation in their sputum.

  • What did you do?

    We collected sputum (by giving a hypertonic saline nebulizer treatment) annually over three years in a group of 35 school age children with CF. We measured a panel of markers (indicators) of inflammation in these sputum samples. We then looked at relationships between sputum inflammation measurements and lung function changes in these children.

  • What did you find?

    We found that sputum inflammation measurements are related to lung function changes in our group of CF children and that measuring inflammation at one time point does appear to predict those children who will have a faster lung function decline over time. In our study, sputum neutrophil elastase was the most helpful marker of inflammation to monitor lung disease activity.

  • What does this mean and reasons for caution?

    This means that treatments that target inflammation, particularly neutrophil elastase, could help to prevent or slow lung function decline in CF. However, our study was relatively small and performed in a single center and may not be applicable to the broader CF community.

  • What's next?

    Next steps will be to see if our findings are similar in a larger CF population including adults, identify high versus low sputum inflammation values for the CF population, and try to figure out how much we need to change or reduce inflammation to lead to a meaningful clinical improvement.