Lower exhaled nitric oxide in infants with Cystic Fibrosis compared to healthy controls

Exhaled nitric oxide (FE; NO; ) is a well-known, non-invasive airway biomarker. In patients with Cystic Fibrosis (CF) FE; NO; is decreased. To understand if reduced FE; NO; is primary related to Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) dysfunction or an epiphenomenon of chronic inflammation, we measured FE; NO; in 34 infants with CF prior to clinical symptoms and in 68 healthy controls. FE; NO; was lower in CF compared to controls (p=0.0006) and the effect was more pronounced in CF infants without residual CFTR function (p<0.0001). This suggests that FE; NO; is reduced in CF early in life, possibly associated with underlying CFTR dysfunction.