title: Diagnostic performance of an electronic nose, fractional exhaled nitric oxide, and lung function testing in asthma.
abstract: BACKGROUND
  Analysis of exhaled breath by biosensors discriminates between patients with asthma and healthy subjects. An electronic nose consists of a chemical sensor array for the detection of volatile organic compounds (VOCs) and an algorithm for pattern recognition. We compared the diagnostic performance of a prototype of an electronic nose with lung function tests and fractional exhaled nitric oxide (FENO) in patients with atopic asthma.
  
  
  METHODS
  A cross-sectional study was undertaken in 27 patients with intermittent and persistent mild asthma and in 24 healthy subjects. Two procedures for collecting exhaled breath were followed to study the differences between total and alveolar air. Seven patients with asthma and seven healthy subjects participated in a study with mass spectrometry (MS) fingerprinting as an independent technique for assessing between group discrimination. Classification was based on principal component analysis and a feed-forward neural network.
  
  
  RESULTS
  The best results were obtained when the electronic nose analysis was performed on alveolar air. Diagnostic performance for electronic nose, FENO, and lung function testing was 87.5%, 79.2%, and 70.8%, respectively. The combination of electronic nose and FENO had the highest diagnostic performance for asthma (95.8%). MS fingerprints of VOCs could discriminate between patients with asthma and healthy subjects.
  
  
  CONCLUSIONS
  The electronic nose has a high diagnostic performance that can be increased when combined with FENO. Large studies are now required to definitively establish the diagnostic performance of the electronic nose. Whether this integrated noninvasive approach will translate into an early diagnosis of asthma has to be clarified.
  
  
  BACKGROUND
  EUDRACT https://eudralink.emea.europa.eu; Identifier: 2007-000890-51; and clinicaltrials.gov; Identifier: NCT00819676.
authors.affiliation: Department of Pharmacology, Faculty of Medicine, Catholic University of the Sacred Heart, Largo F. Vito, 1, 00168 Rome, Italy. pmontuschi@rm.unicatt.it
authors.forename: Paolo
authors.initials: P
authors.lastname: Montuschi
authors.forename: Marco
authors.initials: M
authors.lastname: Santonico
authors.forename: Chiara
authors.initials: C
authors.lastname: Mondino
authors.forename: Giorgio
authors.initials: G
authors.lastname: Pennazza
authors.forename: Giulia
authors.initials: G
authors.lastname: Mantini
authors.forename: Eugenio
authors.initials: E
authors.lastname: Martinelli
authors.forename: Rosamaria
authors.initials: R
authors.lastname: Capuano
authors.forename: Giovanni
authors.initials: G
authors.lastname: Ciabattoni
authors.forename: Roberto
authors.initials: R
authors.lastname: Paolesse
authors.forename: Corrado
authors.initials: C
authors.lastname: Di Natale
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Barnes
authors.forename: Arnaldo
authors.initials: A
authors.lastname: D'Amico
mesh_terms: D000328:Adult; D000465:Algorithms; D001249:Asthma / Q000175:diagnosis* / Q000378:metabolism* / Q000503:physiopathology; D015374:Biosensing Techniques; D001944:Breath Tests; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D003955:Diagnostic Tests, Routine; D045853:Exhalation; D005260:Female; D006801:Humans; D008168:Lung / Q000503:physiopathology; D008297:Male; D013058:Mass Spectrometry; D009569:Nitric Oxide / Q000378:metabolism*; D012129:Respiratory Function Tests; D055549:Volatile Organic Compounds
chemical_list: D055549:Volatile Organic Compounds; D009569:Nitric Oxide