Exhaled breath condensate pH in patients with cystic fibrosis.
OBJECTIVE
Exhaled breath condensate (EBC) pH has been proposed as a useful, non-invasive marker of airway inflammation in pulmonary diseases. In this study we tested whether cystic fibrosis (CF) is associated with acidification of EBC, when pH is assessed by the CO(2) gas standardization method.


METHODS
EBC was collected using two different devices (EcoScreen and R-Tube) in 46 stable CF patients during routine clinical visits and in 28 healthy controls.


RESULTS
Mean EBC pH in CF patients and in healthy controls was similar (EcoScreen: CF patients: 6.38 ± 0.03 versus controls: 6.39 ± 0.03, p = 0.699; R-tube: CF patients: 5.94 ± 0.04 versus controls: 6.02 ± 0.03, p = 0.159). Inflammatory cell counts in spontaneously expectorated sputum obtained in a subset of patients (n = 20) showed no correlation with pH values. EBC samples collected with the R-tube were more acidic than those collected with the EcoScreen device (p < 0.001).


CONCLUSIONS
Our data suggest that EBC pH does not discriminate between healthy controls and those with CF disease indicating that the clinical applicability of EBC pH measurements for assessing airway inflammation in CF is limited.
Department of Pathophysiology, National Koranyi Institute of TB and Pulmonology, Piheno ut 1, Budapest 1121, Hungary. antusb@hotmail.com
Balazs
B
Antus
Imre
I
Barta
Eszter
E
Csiszer
Krisztina
K
Kelemen
D000328:Adult; D001944:Breath Tests; D016022:Case-Control Studies; D003550:Cystic Fibrosis / Q000378:metabolism* / Q000503:physiopathology; D045853:Exhalation; D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D009569:Nitric Oxide / Q000378:metabolism; D012129:Respiratory Function Tests; D013183:Sputum / Q000166:cytology
D009569:Nitric Oxide