Measurement of nasal and fractional exhaled nitric oxide in children with upper airway inflammatory disease: Preliminary results.

OBJECTIVES To assess the clinical significance of nasal nitric oxide (nNO) and fractional exhaled nitric oxide (FeNO) concentrations in children with upper airway inflammatory disease. METHODS Fifteen healthy children, 30 with allergic rhinitis (AR), 10 with non-allergic rhinitis (NAR), and 30 with sleep disordered breathing (SDB) were enrolled. The FeNO and nNO concentrations were measured non-invasively using a NIOX MINO system. RESULTS Both nNO and FeNO were significantly higher in children with AR than in healthy children (P=0.000 and P=0.000, respectively). Compared to healthy children, nNO was also significant higher in children with NAR (P=0.011) or SDB (P=0.027). In contrast, FeNO did not differ from controls in children with NAR or SDB. CONCLUSIONS Our data suggest that nNO has potential value for diagnosing upper airway inflammation. Moreover, elevated FeNO distinguishes allergic from non-allergic rhinitis.