title: Hydrogen peroxide in breath condensate during a common cold.
abstract: BACKGROUND
  Hydrogen peroxide (H2O2) in exhaled air condensate is elevated in inflammatory disorders of the lower respiratory tract. It is unknown whether viral colds contribute to exhaled H2O2.
  
  
  OBJECTIVE
  To assess exhaled H2O2 during and after a common cold.
  
  
  METHODS
  We examined H2O2 in the breath condensate of 20 normal subjects with acute symptoms of a common cold and after recovery 2 weeks later and, similarly, in 10 subjects without infection. H2O2 was measured with a fluorimetric assay.
  
  
  RESULTS
  At the time of infection exhaled H2O2 (median, ranges) was 0.20 microM (0.03-1.2 microM), and this decreased to 0.09 microM (< 0.01-0.40 microM) after recovery (p = 0.006). There was no significant difference in lung function (forced vital capacity and forced expiratory volume in 1 sec) during and after colds. In the controls, exhaled H2O2 did not change over a 2-week period.
  
  
  CONCLUSIONS
  H2O2 in exhaled air condensate is elevated during a common cold, and returns to normal within 2 weeks of recovery in healthy subjects. Hence, symptomatic upper respiratory tract infection may act as a confounder in studies of H2O2 as a marker of chronic lower airway inflammation.
authors.affiliation: Department of Paediatrics, Division of Paediatric Respiratory Medicine, Erasmus University Medical Center/Sophia Children's Hospital, Rotterdam, The Netherlands.
authors.forename: R Q
authors.initials: RQ
authors.lastname: Jöbsis
authors.forename: S L
authors.initials: SL
authors.lastname: Schellekens
authors.forename: A
authors.initials: A
authors.lastname: Fakkel-Kroesbergen
authors.forename: R H
authors.initials: RH
authors.lastname: Raatgeep
authors.forename: J C
authors.initials: JC
authors.lastname: de Jongste
mesh_terms: D000328:Adult; D001944:Breath Tests; D003139:Common Cold / Q000175:diagnosis* / Q000378:metabolism*; D005260:Female; D006801:Humans; D006861:Hydrogen Peroxide / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests
chemical_list: D006861:Hydrogen Peroxide