title: Markers of inflammation in the breath in paediatric inflammatory bowel disease.
abstract: OBJECTIVE
  Breath analysis and exhaled breath condensate (EBC) collection are simple and noninvasive processes whereby inflammatory mediators and other biomarkers can be assessed in diseases that affect the lung. It was hypothesised that markers of epithelial dysfunction and secretion, such as a low pH, 8-isoprostane, and release of epithelial factors such as trefoil factor 2 (TFF2) and mucin, would be elevated in the breath of those with inflammatory bowel disease (IBD). The aim was to compare the levels of these biomarkers in EBC and the fraction of expired nitric oxide (FENO) in children with Crohn disease (CD), in those with asthma, and in normal individuals in a pilot study.
  
  
  METHODS
  EBC was collected from patients in the 3 groups mentioned above in a cross-sectional design. pH, 8-isoprostane, TFF2, and mucin levels were measured in the EBC. Spirometry was performed in asthmatic patients and patients with IBD, whereas FENO and skin prick tests were performed in patients with IBD.
  
  
  RESULTS
  Breath samples including EBC were collected from 80 patients (30 CD, 30 asthma, 20 controls). Compared with controls, EBC pH was lower in children with IBD (P < 0.0001) or asthma (P = 0.0041). 8-Isoprostane levels differed between the 3 groups (P < 0.05). EBC TFF2 was mainly less than the limit of detection, whereas mucin levels did not differ significantly between the 3 groups. FENO was measurable in children with IBD, but did not correlate with disease activity or serum markers of inflammation.
  
  
  CONCLUSIONS
  A lower EBC pH may reflect inflammatory events either in the lung or systemically. 8-Isoprostane, FENO, and mucin were detected for the first time in the EBC of children with IBD. Further studies are required to assess the value of these assessments.
authors.affiliation: *Inflammation and Infection Research Centre, Faculty of Medicine, University of New South Wales †Edmond and Lili Safra Children's Hospital, Tel Hashomer, Israel ‡Department of Paediatrics, University of Otago, Christchurch, New Zealand §School of Women's and Children's Health, University of New South Wales, Sydney, Australia.
authors.forename: Yixi
authors.initials: Y
authors.lastname: Huang
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Lemberg
authors.forename: Andrew S
authors.initials: AS
authors.lastname: Day
authors.forename: Barbara
authors.initials: B
authors.lastname: Dixon
authors.forename: Steven
authors.initials: S
authors.lastname: Leach
authors.forename: Yoram
authors.initials: Y
authors.lastname: Bujanover
authors.forename: Adam
authors.initials: A
authors.lastname: Jaffe
authors.forename: Paul S
authors.initials: PS
authors.lastname: Thomas
mesh_terms: D000293:Adolescent; D001249:Asthma / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D001944:Breath Tests; D002648:Child; D003424:Crohn Disease / Q000378:metabolism*; D003430:Cross-Sectional Studies; D015237:Dinoprost / Q000031:analogs & derivatives; D045853:Exhalation; D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007249:Inflammation / Q000378:metabolism*; D018836:Inflammation Mediators / Q000378:metabolism; D028421:Isoprostanes / Q000378:metabolism*; D008168:Lung / Q000378:metabolism*; D008297:Male; D009077:Mucins / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism*; D010455:Peptides / Q000378:metabolism*; D010865:Pilot Projects; D012016:Reference Values; D000071164:Trefoil Factor-2
chemical_list: D015415:Biomarkers; D018836:Inflammation Mediators; D028421:Isoprostanes; D009077:Mucins; D010455:Peptides; C000604007:TFF2 protein, human; D000071164:Trefoil Factor-2; C075750:8-epi-prostaglandin F2alpha; D009569:Nitric Oxide; D015237:Dinoprost