title: Exhaled air temperature in asthma: methods and relationship with markers of disease.
abstract: BACKGROUND
  Exhaled breath temperature has been proposed as a surrogate marker for the evaluation of airway inflammation in asthmatic patients.
  
  
  OBJECTIVE
  The aim of the present study was to extend the investigation of exhaled air temperature as a means for the evaluation of airway inflammation using a professionally developed instrument.
  
  
  METHODS
  Fifty-seven children, 41 allergic mild asthmatics and 16 healthy controls have been evaluated. They underwent exhaled air temperature and lung function measurement. The asthmatic children also underwent exhaled nitric oxide measurement, and hypertonic saline sputum induction for the evaluation of eosinophil (EOS) percentage.
  
  
  RESULTS
  The level of exhaled temperature was significantly higher in asthmatics than in controls, being 30.18+/-0.14 degrees C vs. 27.47+/-0.24 degrees C (P<0.001). In asthmatic children, a positive relationship was observed between exhaled air temperature and both exhaled nitric oxide (r=0.39; P=0.01) and EOS percentage in samples from induced sputum (rho=0.53; P=0.04).
  
  
  CONCLUSIONS
  The data from the present study support the hypotheses that exhaled breath temperature is related to the degree of airway inflammation in asthma.
authors.affiliation: Clinica Pediatrica Università di Verona - Verona, Italy. giorgio.piacentini@univr.it
authors.forename: G L
authors.initials: GL
authors.lastname: Piacentini
authors.forename: D
authors.initials: D
authors.lastname: Peroni
authors.forename: E
authors.initials: E
authors.lastname: Crestani
authors.forename: F
authors.initials: F
authors.lastname: Zardini
authors.forename: A
authors.initials: A
authors.lastname: Bodini
authors.forename: S
authors.initials: S
authors.lastname: Costella
authors.forename: A L
authors.initials: AL
authors.lastname: Boner
mesh_terms: D000293:Adolescent; D001249:Asthma / Q000175:diagnosis*; D015415:Biomarkers; D001944:Breath Tests / Q000379:methods; D016022:Case-Control Studies; D002648:Child; D005260:Female; D006801:Humans; D007249:Inflammation; D008297:Male; D011237:Predictive Value of Tests; D013696:Temperature
chemical_list: D015415:Biomarkers