title: Exhaled nitric oxide and biomarkers in exhaled breath condensate indicate the presence, severity and control of childhood asthma.
abstract: BACKGROUND
  Exhaled nitric oxide and inflammatory biomarkers in exhaled breath condensate may be useful to diagnose and monitor childhood asthma. Their ability to indicate an asthma diagnosis, and to assess asthma severity and control, is largely unknown.
  
  
  OBJECTIVE
  To study (1) the ability of exhaled nitric oxide and inflammatory markers in exhaled breath condensate (nitrite, nitrate, hydrogen peroxide, 8-isoprostane, IFN-gamma, TNF-alpha, IL-2, -4, -5, -10 and acidity) to discriminate between childhood asthma and controls. (2) The ability of these biomarkers to indicate asthma severity and control.
  
  
  METHODS
  One-hundred and fourteen children were included: 64 asthmatics (10.7+/-3.0 years, 67.2% atopic) and 50 controls (10.0+/-0.4 years). Condensate was collected using a glass condenser.
  
  
  RESULTS
  Exhaled nitric oxide, IFN-gamma and IL-4 in exhaled breath condensate differed significantly between asthma and controls. Multivariate backward logistic regression models demonstrated that IL-4 (odds ratio 7.9, 95% confidence interval 1.2-51.0) was the only significant indicator of an asthma diagnosis. Asthma control was best assessed by exhaled nitric oxide, 8-isoprostane, IFN-gamma and IL-4 (sensitivity 82%, specificity 80%, P<0.05), whereas exhaled nitric oxide, 8-isoprostane, nitrate and nitrite in condensate were the best indicators of asthma severity (sensitivity 89%, specificity 72%, P<0.05).
  
  
  CONCLUSIONS
  Different markers in condensate are of an additional value to exhaled nitric oxide, and are needed in non-invasive inflammometry. They could be useful to diagnose asthma and to indicate asthma control and severity in childhood.
authors.affiliation: Department of Paediatric Pulmonology, University Hospital Maastricht, Maastricht, The Netherlands. crob@paed.azm.nl
authors.forename: C M H H T
authors.initials: CM
authors.lastname: Robroeks
authors.forename: K D G
authors.initials: KD
authors.lastname: van de Kant
authors.forename: Q
authors.initials: Q
authors.lastname: Jöbsis
authors.forename: H J E
authors.initials: HJ
authors.lastname: Hendriks
authors.forename: R
authors.initials: R
authors.lastname: van Gent
authors.forename: E F M
authors.initials: EF
authors.lastname: Wouters
authors.forename: J G M C
authors.initials: JG
authors.lastname: Damoiseaux
authors.forename: A
authors.initials: A
authors.lastname: Bast
authors.forename: W K W H
authors.initials: WK
authors.lastname: Wodzig
authors.forename: E
authors.initials: E
authors.lastname: Dompeling
mesh_terms: D000293:Adolescent; D001249:Asthma / Q000175:diagnosis*; D015415:Biomarkers / Q000032:analysis; D001944:Breath Tests; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D015237:Dinoprost / Q000031:analogs & derivatives / Q000032:analysis; D045853:Exhalation; D005260:Female; D006801:Humans; D007371:Interferon-gamma / Q000032:analysis; D015847:Interleukin-4 / Q000032:analysis; D008297:Male; D009566:Nitrates / Q000032:analysis; D009569:Nitric Oxide / Q000032:analysis*; D009573:Nitrites / Q000032:analysis; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index
chemical_list: D015415:Biomarkers; D009566:Nitrates; D009573:Nitrites; D015847:Interleukin-4; C075750:8-epi-prostaglandin F2alpha; D009569:Nitric Oxide; D007371:Interferon-gamma; D015237:Dinoprost