The Severe Asthma Phenotype Is Characterized by Elevated Levels of Formate in Exhaled Breath Condensate.

Determinants of Exhaled Breath Condensate pH in a Large Population With Asthma

“…1,7,35 Additionally, S-nitrosoglutathione (GSNO) metabo- determinant of asthmatic airway acidifi cation. 18,42,43 Therefore, the subset of patients with increased GSNO reductase activity might be predicted to have low F e NO and low EBC pH. One way or another, this subset appears to be biochemically unique and may be a subset in which the metabolomically targeted therapy (for example, with inhaled base 7,35 ) may be particularly benefi cial.…”

“…A subpopulation of patients with chronic cough who have consistently low EBC pH on serial studies at home appear to be those patients whose cough can be successfully treated with high-dose proton pump inhibitor therapy. 18 However, the fi nding is based on a subjective questionnaire. Prospective studies will be needed to determine whether a specifi c EBC pH will be useful in predicting responses to antacid-class therapies in asthma.…”