The pH of exhaled breath condensate (EBC): A non invasive tool for evaluation of asthma in childhood

Recent studies show that the pH of EBC could be predictive of asthma exacerbation in adults. However no data are available in children. The aim of our study was to establish if EBC pH could be used as a non-invasive mean of monitoring asthma in childhood. Between April and July 2002, a total of 104 consecutive patients with mild persistent asthma (72 M, median age 9.9 years) were enrolled. Thirty healthy children were used as controls (11 M, median age 7 years). All children performed skin prick tests, lung function tests and EBC pH measurements, using a hand-made device. Patients with asthma exacerbation received steroid and β2-agonist treatment for one week, and then the EBC pH determination was repeated. Out of 104 patients, 34 (32.7%) showed evidences of acute exacerbation of asthma (AA) and 70 (67.3%) had stable asthma (SA). We found that the pH of EBC in patients with AA was significantly lower than that of patients with SA (7.25 vs 7.32; p