A. Antczak et al., INCREASED HYDROGEN-PEROXIDE AND THIOBARBITURIC ACID-REACTIVE PRODUCTSIN EXPIRED BREATH CONDENSATE OF ASTHMATIC-PATIENTS, The European respiratory journal, 10(6), 1997, pp. 1235-1241
Symptoms of bronchial asthma are a manifestation of airway inflammatio
n, Circulatory leucocytes (predominantly eosinophils, mast cells and n
eutrophils), release inflammatory mediators, including reactive oxygen
species, i.e. superoxide anion which is dismutated to hydrogen peroxi
de (H2O2) Neutrophils from asthmatics generate greater amounts of thes
e species than those of healthy subjects, Some of the H2O2 and thiobar
bituric acid-reactive products (TBARs) can evaporate from alveolar lin
ing fluid, and could be expired from the airways of asthmatics, In thi
s study, therefore, we determined whether asthmatic patients exhale mo
re H2O2 and TBARs than healthy subjects. We examined 10 healthy subjec
ts as a control group and 21 asthmatic subjects, In asthmatic subjects
, forced expiratory volume in one second (FEV1), was 68+/-9% of predic
ted value, peak expiratory flow rate (PEFR) was 65+/-8% pred, and bron
chial reversibility was 34+/-5% of prebronchodilated FEV1, The mean H2
O2 level measured spectrofluorimetrically in the expired breath conden
sate of asthmatic subjects was 26 fold higher than that in healthy con
trols (0.26+/-0.29 vs 0.01+/-0.03 nM; p<0.05), The concentration of TB
ARs in breath condensate was also higher in asthmatic patients compare
d with nonasthmatics (0.073+/-0.071 vs 0.004+/-0.009 nM; p<0.05), Ther
e was a significant correlation between H2O2 level and concentration o
f TBARs in asthmatic patients (r=0.74; p<0.01), There was also a stron
g inverse correlation between H2O2 content of all asthmatics and FEV1%
pred (r= -0.63; p<0.005) and PEFR% pred (r= -0.52; p<0.05). We conclu
de that there are elevated levels of hydrogen peroxide and thiobarbitu
ric acid-reactive products in expired breath condensate of asthmatic p
atients, and that measurement of these substances in the expired breat
h condensate could be a simple, noninvasive method that could be used
as a biochemical marker of airway inflammation.