title: Exhaled 8-isoprostane in childhood asthma.
abstract: BACKGROUND
  Exhaled breath condensate (EBC) is a non-invasive method to assess airway inflammation and oxidative stress and may be useful in the assessment of childhood asthma.
  
  
  METHODS
  Exhaled 8-isoprostane, a stable marker of oxidative stress, was measured in EBC, in children (5-17 years) with asthma (13 steroid-naïve and 12 inhaled steroid-treated) and 11 healthy control.
  
  
  RESULTS
  Mean exhaled 8-isoprostane concentration was significantly elevated in steroid-naïve asthmatic children compared to healthy children 9.3 (SEM 1.7) vs. 3.8 (0.6) pg/ml, p < 0.01. Children on inhaled steroids also had significantly higher 8-isoprostane levels than those of normal subjects 6.7 (0.7) vs. 3.8 (0.6) pg/ml, p < 0.01. Steroid-naïve asthmatics had higher exhaled nitric oxide (eNO) than those of controls 28.5 (4.7) vs. 12.6 (1.5) ppb, p < 0.01. eNO in steroid-treated asthmatics was similar to control subjects 27.5(8.8) vs. 12.6(1.5) ppb. Exhaled 8-isoprostane did not correlate with duration of asthma, dose of inhaled steroids or eNO.
  
  
  CONCLUSIONS
  We conclude that 8-isoprostane is elevated in asthmatic children, indicating increased oxidative stress, and that this does not appear to be normalized by inhaled steroid therapy. This suggests that 8-isoprostane is a useful non-invasive measurement of oxidative stress in children and that antioxidant therapy may be useful in the future.
authors.affiliation: National Heart and Lung Institute, Imperial College London, London, UK. a.bush@ic.ac.uk
authors.forename: Sukhbir K
authors.initials: SK
authors.lastname: Shahid
authors.forename: Sergei A
authors.initials: SA
authors.lastname: Kharitonov
authors.forename: Nicola M
authors.initials: NM
authors.lastname: Wilson
authors.forename: Andrew
authors.initials: A
authors.lastname: Bush
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Barnes
mesh_terms: D000293:Adolescent; D001249:Asthma / Q000175:diagnosis* / Q000378:metabolism*; D015415:Biomarkers / Q000032:analysis*; D001944:Breath Tests / Q000379:methods*; D002648:Child; D002675:Child, Preschool; D015237:Dinoprost / Q000031:analogs & derivatives* / Q000032:analysis; D045853:Exhalation; D005260:Female; D006801:Humans; D008168:Lung / Q000378:metabolism*; D008297:Male; D009569:Nitric Oxide / Q000032:analysis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D015415:Biomarkers; C075750:8-epi-prostaglandin F2alpha; D009569:Nitric Oxide; D015237:Dinoprost