Noninvasive markers of airway inflammation in asthma

Clin Transl Sci. 2009 Apr;2(2):112-7. doi: 10.1111/j.1752-8062.2009.00095.x.


Background: Although airway inflammation plays a major role in the pathophysiology of asthma, quantitative markers of airway inflammation are limited in clinical practice.

Objective: To determine if levels of noninvasive markers of eosinophil-catalyzed oxidation, lipid peroxidation, and nitric oxide production are associated with asthma.

Methods: Participants were enrolled from academic medical centers participating in the Severe Asthma Research Program. Clinical characteristics, laboratory data, pulmonary function tests, and levels of the following noninvasive markers were obtained: urinary bromotyrosine, a marker of eosinophil-catalyzed oxidation; urinary F(2)-isoprostanes, markers of lipid peroxidation; and exhaled nitric oxide, a marker of airway inflammation

Results: Fifty-seven asthmatic participants and thirty-eight healthy participants were enrolled. Bromotyrosine, F(2)-isoprostanes, and exhaled nitric oxide were each significantly increased in asthmatic participants versus controls (p<0.01). An elevated level (greater than median) of any marker was associated with a significant 3- to 6-fold greater odds of having asthma. Participants with two or more elevated marker levels showed an 18-fold greater odds of having asthma. Relationships were also noted with airflow obstruction and bronchodilator response.

Conclusion: Findings from this pilot study indicate that urinary levels of bromotyrosine and F(2)-isoprostanes, in addition to exhaled nitric oxide levels, are associated with asthma.

Keywords: Asthma; Biomarkers; Inflammation.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Asthma / complications*
  • Asthma / diagnosis
  • Asthma / pathology
  • Asthma / urine*
  • Biomarkers / urine*
  • Confidence Intervals
  • Female
  • Humans
  • Inflammation / complications*
  • Inflammation / urine*
  • Male
  • Odds Ratio
  • Respiratory System / pathology*
  • Young Adult


  • Biomarkers