title: Analysis of exhaled leukotrienes in nonasthmatic adult patients with seasonal allergic rhinitis.
abstract: BACKGROUND
  Leukotrienes (LTs) are increased in exhaled breath condensate (EBC) in patients with asthma. So far no data have been reported about LT levels in nonasthmatic patients with seasonal allergic rhinitis (SAR). The aim of the study was to find out whether the LT levels in EBC were increased in the nonasthmatic adult patients with SAR both during and after the pollen season in comparison with healthy controls and to assess the changes of the LT levels after the pollen season.
  
  
  METHODS
  Twenty-nine nonasthmatic adult patients with SAR underwent measurement of exhaled LTs in the EBC during and after the pollen season. Leukotrienes B(4), C(4), D(4) and E(4) were analysed by a specific and sensitive gas chromatography/mass spectrometry (GC/MS) assay and compared with 50 healthy nonsmoking controls. Spirometry, skin prick tests and nonspecific IgE were evaluated.
  
  
  RESULTS
  Leukotrienes concentrations (B(4), E(4) but not D(4)) were significantly increased in and after the pollen season in patients with SAR in comparison with healthy controls. In most of the samples, LT C(4) was undetectable. The values of all exhaled LTs were significantly decreased after the pollen season compared with the seasonal baseline: LTB(4) (P = 0.023), LTD(4) (P = 0.020), LTE(4) (P = 0.047).
  
  
  CONCLUSIONS
  Levels of exhaled LTB(4) and LTE(4) were higher in SAR patients than in healthy controls and decreased after the pollen season as compared with levels in season. The SAR patients with the highest in season LT levels had also the post-season levels elevated and this may be an early marker of inflammatory process in the lower airways despite the absence of clinical symptoms of asthma.
authors.affiliation: Department of Allergology and Clinical Immunology, Hospital Na Homolce, Institute for Postgraduate Medical Education, Prague, Czech Republic.
authors.forename: P
authors.initials: P
authors.lastname: Cáp
authors.forename: F
authors.initials: F
authors.lastname: Pehal
authors.forename: J
authors.initials: J
authors.lastname: Chládek
authors.forename: M
authors.initials: M
authors.lastname: Malý
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D045853:Exhalation; D005260:Female; D006801:Humans; D007975:Leukotriene B4; D017999:Leukotriene E4; D008297:Male; D008875:Middle Aged; D009994:Osmolar Concentration; D011058:Pollen; D006255:Rhinitis, Allergic, Seasonal / Q000503:physiopathology*; D012621:Seasons
chemical_list: D007975:Leukotriene B4; D017999:Leukotriene E4