Exhaled nitric oxide differentiates airway diseases in the first two years of life

Abstract

Fractional exhaled nitric oxide (FENO) levels are increased in children and adults with asthma, whereas low levels have been found in cystic fibrosis and primary ciliary dyskinesia. The aim of this study was to investigate whether FENO measurements could distinguish between children below the age of 2 with different airway diseases. FENO measurements were performed in 118 infants aged between 4.6 and 25.2 mo: 74 infants with recurrent wheezing (RW), 24 with bronchopulmonary dysplasia (BPD), and 20 with cystic fibrosis (CF). FENO was measured also in 100 healthy controls aged between 1.1 and 7.7 mo. Geometric mean (95% confidence interval) FENO values were 10.4 (9.1-12.0) parts per billion (ppb) in healthy infants, 18.6 (15.6-22.2) ppb in wheezy infants, 11.7 (8.2-16.8) ppb in BPD infants and 5.9 (3.4-10.1) ppb in CF infants. FENO in wheezers was higher than in controls, BPD, and CF (p = 0.009, p = 0.038, and p < 0.001, respectively). Atopic wheezers showed higher FENO than nonatopic wheezers (p = 0.04). CF infants had lower FENO than healthy controls and BPD infants (p = 0.003 and p = 0.043, respectively). FENO values in BPD and control infants were not different. We conclude that FENO is helpful to differentiate various airway diseases already in the first 2 y of life. Copyright © 2006 International Pediatric Research Foundation, Inc.