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

Exhaled nitric oxide (FENO) is a well-known, non-invasive airway biomarker. In patients with Cystic Fibrosis (CF) FENO is decreased. To understand if reduced FENO is primary related to Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) dysfunction or an epiphenomenon of chronic inflammation, we measured FENO in 34 infants with CF prior to clinical symptoms and in 68 healthy controls. FENO 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 FENO is reduced in CF early in life, possibly associated with underlying CFTR dysfunction.