title: Exhaled nitric oxide and breath condensate ph in asthmatic reactions induced by isocyanates.
abstract: BACKGROUND
  We investigated the usefulness of measurements of fractional exhaled nitric oxide (FeNO) and pH of exhaled breath condensate (EBC) for monitoring airway response after specific inhalation challenges with isocyanates in sensitized subjects.
  
  
  METHODS
  Lung function (FEV(1)), FeNO, and pH in argon-deaerated EBC were measured before and at intervals up to 30 days after a specific inhalation challenge in 15 subjects with isocyanate asthma, in 24 not sensitized control subjects exposed to isocyanates, and in 3 nonasthmatic subjects with rhinitis induced by isocyanate. Induced sputum was collected before and 24 h after isocyanate exposure.
  
  
  RESULTS
  Isocyanate-induced asthmatic reactions were associated with a rise in sputum eosinophil levels at 24 h (p < 0.01), and an increase in FeNO at 24 h (p < 0.05) and 48 h (p < 0.005), whereas FeNO level did not vary with isocyanate exposure in subjects with rhinitis and in control subjects. FeNO changes at 24 h positively correlated with corresponding sputum eosinophil changes (rho = 0.66, p < 0.001). A rise in pH was observed in the afternoon samples of EBC, irrespective of the occurrence of isocyanate-induced asthmatic reactions.
  
  
  CONCLUSIONS
  We demonstrated that isocyanate-induced asthmatic reactions are associated with a consistent delayed increase in FeNO but not with the acidification of EBC.
authors.affiliation: Department of Environmental Medicine and Public Health, University of Padova, Padova, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Ferrazzoni
authors.affiliation: Department of Environmental Medicine and Public Health, University of Padova, Padova, Italy.
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Scarpa
authors.affiliation: Department of Environmental Medicine and Public Health, University of Padova, Padova, Italy.
authors.forename: Gabriella
authors.initials: G
authors.lastname: Guarnieri
authors.affiliation: Department of Clinical Medicine, Nephrology, and Health Sciences, University of Parma, Parma, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Corradi
authors.affiliation: Department of Clinical Medicine, Nephrology, and Health Sciences, University of Parma, Parma, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Mutti
authors.affiliation: Department of Environmental Medicine and Public Health, University of Padova, Padova, Italy. Electronic address: piero.maestrelli@unipd.it.
authors.forename: Piero
authors.initials: P
authors.lastname: Maestrelli
mesh_terms: D000328:Adult; D001249:Asthma / Q000139:chemically induced* / Q000175:diagnosis* / Q000378:metabolism; D001944:Breath Tests; D001985:Bronchial Provocation Tests; D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D017953:Isocyanates / Q000009:adverse effects*; D008297:Male; D009569:Nitric Oxide / Q000378:metabolism*; D009784:Occupational Diseases / Q000139:chemically induced / Q000175:diagnosis* / Q000378:metabolism; D016273:Occupational Exposure / Q000009:adverse effects; D011237:Predictive Value of Tests; D016037:Single-Blind Method; D013997:Time Factors
chemical_list: D017953:Isocyanates; D009569:Nitric Oxide