title: Correlation of atopy and FeNO in allergic rhinitis: an Indian study.
abstract: BACKGROUND
  Fractional exhaled nitric oxide (FeNO) is a non-invasive marker of airway inflammation. Limited published data are available on the effect of atopy on FeNO in allergic rhinitis.
  
  
  OBJECTIVE
  To investigate the relationship between atopy and FeNO in patients with allergic rhinitis.
  
  
  METHODS
  Patients with allergic rhinitis were assessed for atopy and exhaled breath analysis of nitric oxide. Atopy was assessed by skin prick testing (SPT) against 58 common aero-allergens; a wheal size of 3mm or more as compared to buffer saline was considered positive. Patients were labelled to be atopic if they had at least one positive SPT result. The measurement of FeNO level was done by using NIOX chemiluminescence analyser.
  
  
  RESULTS
  Forty-nine participants (26 males) aged between 8-50 years were studied and 31 of them were found to be atopic. The average value of FeNO in the subjects studied (n = 49) was 26.0 +/- 22.7 parts per billion (ppb) with significantly higher values being observed in atopic group as compared to non-atopic group (34.2 +/- 24.3 versus 11.9 +/- 9.0 ppb; p < 0.05).
  
  
  CONCLUSIONS
  As FeNO is a marker of lower airway inflammation, significantly higher FeNO levels in atopic allergic rhinitis patients suggest that it may be a predictor for onset of asthma in these patients.
authors.affiliation: National Centre of Respiratory Allergy, Asthma and Immunology, Department of Respiratory Allergy and Applied Immunology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India. rajkumarvpci@gmail.com
authors.forename: Raj
authors.initials: R
authors.lastname: Kumar
authors.forename: Nitesh
authors.initials: N
authors.lastname: Gupta
authors.forename: Nitin
authors.initials: N
authors.lastname: Goel
mesh_terms: D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000032:analysis; D001944:Breath Tests; D002648:Child; D045853:Exhalation; D006801:Humans; D007194:India / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000378:metabolism*; D065631:Rhinitis, Allergic; D012221:Rhinitis, Allergic, Perennial / Q000378:metabolism* / Q000473:pathology; D012882:Skin Tests
chemical_list: D015415:Biomarkers; D009569:Nitric Oxide