title: Oxidative stress in the airways of children with asthma and allergic rhinitis.
abstract: BACKGROUND
  Even though it is well known that oxidant stress plays an important role in the pathogenesis of asthma, less is known about allergic rhinitis. Moreover, it is not known whether the co-existence of the two diseases augments the level of oxidant stress within a united airway concept.
  
  
  OBJECTIVE
  To define the level of oxidative stress in children with asthma and/or allergic rhinitis in nasal and oral exhaled breath condensates (EBC) of children.
  
  
  METHODS
  Children aged 6-18 years with asthma (n = 28), allergic rhinitis (n = 17), asthma and allergic rhinitis (n = 100), and healthy controls (n = 74) were enrolled in the study. Levels of malondialdehyde (MDA) as a marker of oxidative stress and reduced glutathione (GSH) as an antioxidant were measured by High-Performance Liquid Chromatography in the EBC.
  
  
  RESULTS
  Malondialdehyde levels were higher, and GSH levels were lower in all patient groups compared to healthy controls in both nasal and oral EBC samples (p < 0.01) but there were no differences among the different patient groups. Interestingly, oral MDA levels were lower in patients with asthma and allergic rhinitis [17.78 nM (11.62-23.94)] compared to patients with asthma only [25.71 nM (18.81-32.61)] (p < 0.01).
  
  
  CONCLUSIONS
  Both asthma and allergic rhinitis are associated with increased oxidative stress in the airways in children. However, the co-existence of the two diseases does not augment the oxidant stress further.
authors.affiliation: Pediatric Allergy and Asthma Unit, Ihsan Dogramaci Children's Hospital, Hacettepe University School of Medicine, Ankara, Turkey.
authors.forename: Melda
authors.initials: M
authors.lastname: Celik
authors.forename: Ayfer
authors.initials: A
authors.lastname: Tuncer
authors.forename: Ozge U
authors.initials: OU
authors.lastname: Soyer
authors.forename: Cansın
authors.initials: C
authors.lastname: Saçkesen
authors.forename: H
authors.initials: H
authors.lastname: Tanju Besler
authors.forename: Omer
authors.initials: O
authors.lastname: Kalayci
mesh_terms: D000293:Adolescent; D001249:Asthma / Q000378:metabolism*; D015415:Biomarkers / Q000032:analysis; D001944:Breath Tests; D002648:Child; D002851:Chromatography, High Pressure Liquid; D005260:Female; D005978:Glutathione / Q000032:analysis; D006801:Humans; D008297:Male; D008315:Malondialdehyde / Q000032:analysis; D018384:Oxidative Stress; D065631:Rhinitis, Allergic; D012221:Rhinitis, Allergic, Perennial / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D008315:Malondialdehyde; D005978:Glutathione