Exhaled nitric oxide is reduced in infants with cystic fibrosis.

BACKGROUND Exhaled nitric oxide levels are low in patients with cystic fibrosis (CF), despite the chronic inflammation present in the airways. This study aimed to determine whether levels of exhaled nitric oxide were reduced prior to the onset of respiratory symptoms in infants with CF. METHODS The levels of exhaled nitric oxide were measured using a chemiluminescence analyser in five infants with CF and 11 healthy control subjects, both groups having a mean age of 48.6 days. RESULTS Mean levels of exhaled nitric oxide were significantly lower in infants with CF than in the control group (4.9 ppb v 12.1 ppb; p=0.01). CONCLUSIONS This finding may be the key to understanding the inflammatory processes in early cystic fibrosis and may lead to novel treatment approaches.