Nitrites and nitrates in exhaled breath condensate in cystic fibrosis: relation to clinical parameters.

Objectives: To evaluate correlation of exhaled breath condensate (EBC) nitrite and nitrate concentra- tions with disease severity in cystic fi brosis (CF) patients. Background: Nitrites and nitrates are products of oxidative metabolism of nitric oxide. Impaired metabolism of nitric oxide plays a role in pathogenesis of CF. Methods: EBC was collected from 46 stable CF patients and from 21 healthy controls. EBC concentrations of nitrites and nitrates were correlated with parameters of lung disease and nutritional status and with systemic infl ammatory markers. Results: EBC nitrates concentrations in CF patients were lower than in healthy subjects (5.8 vs 14.3 μmol/l, p<0.001). They correlated positively with FEV 1 (p=0.025) and serum albumin values (p=0.016) and negatively with chest radiograph Northern score (p=0.015) and serum C-reactive protein values (p=0.005). EBC nitrites concentrations in CF patients did not differ from those in healthy subjects and were not correlated to any stud- ied parameter. Conclusions: EBC nitrates concentrations correlate with disease severity in CF patients and are lower than in