BACKGROUND: It has been proposed that the pH of airway lining fluid may regulate the fractional exhaled concentration of nitric oxide (Fe(NO)) in respiratory disease. METHODS: Fe(NO), exhaled breath condensate (EBC) pH, and EBC concentrations of nitrite plus nitrate (NO2/NO3) were compared in 12 subjects with stable asthma, 18 with stable cystic fibrosis (CF), and 15 healthy control subjects. Eight of the CF patients were studied on a separate occasion at the start of a pulmonary exacerbation. RESULTS: Fe(NO) was significantly greater in asthmatic subjects than in control subjects (mean 35 v 9 ppb, p<0.001). EBC pH, however, was similar in the asthmatic and control groups (median 5.82 v 6.08, p=0.23). Levels of NO2/NO3 were on average higher in EBC samples from asthmatic subjects, but the difference was not significant. In patients with stable CF both the Fe(NO) (mean 4 ppb, p<0.001) and EBC pH (median 5.77, p=0.003) were lower than in the control group. Levels of EBC NO2/NO3 (median 29.9 microM; p=0.002) in patients with stable CF, in contrast, were significantly higher than in control subjects. During CF exacerbations, EBC pH was further reduced (median 5.30, p=0.017) but Fe(NO) and NO2/NO3 were unchanged. CONCLUSIONS: These findings demonstrate a dissociation between EBC pH and Fe(NO) in inflammatory airways disease.
BACKGROUND: It has been proposed that the pH of airway lining fluid may regulate the fractional exhaled concentration of nitric oxide (Fe(NO)) in respiratory disease. METHODS:Fe(NO), exhaled breath condensate (EBC) pH, and EBC concentrations of nitrite plus nitrate (NO2/NO3) were compared in 12 subjects with stable asthma, 18 with stable cystic fibrosis (CF), and 15 healthy control subjects. Eight of the CF patients were studied on a separate occasion at the start of a pulmonary exacerbation. RESULTS:Fe(NO) was significantly greater in asthmatic subjects than in control subjects (mean 35 v 9 ppb, p<0.001). EBC pH, however, was similar in the asthmatic and control groups (median 5.82 v 6.08, p=0.23). Levels of NO2/NO3 were on average higher in EBC samples from asthmatic subjects, but the difference was not significant. In patients with stable CF both the Fe(NO) (mean 4 ppb, p<0.001) and EBC pH (median 5.77, p=0.003) were lower than in the control group. Levels of EBCNO2/NO3 (median 29.9 microM; p=0.002) in patients with stable CF, in contrast, were significantly higher than in control subjects. During CF exacerbations, EBC pH was further reduced (median 5.30, p=0.017) but Fe(NO) and NO2/NO3 were unchanged. CONCLUSIONS: These findings demonstrate a dissociation between EBC pH and Fe(NO) in inflammatory airways disease.
Authors: H Kanazawa; S Shoji; M Yamada; T Fujii; T Kawaguchi; S Kudoh; K Hirata; J Yoshikawa Journal: J Allergy Clin Immunol Date: 1997-05 Impact factor: 10.793
Authors: Xiaoling Zang; José J Pérez; Christina M Jones; María Eugenia Monge; Nael A McCarty; Arlene A Stecenko; Facundo M Fernández Journal: J Am Soc Mass Spectrom Date: 2017-03-31 Impact factor: 3.109
Authors: Rembert Koczulla; Silvano Dragonieri; Robert Schot; Robert Bals; Stefanie A Gauw; Claus Vogelmeier; Klaus F Rabe; Peter J Sterk; Pieter S Hiemstra Journal: Respir Res Date: 2009-08-24