Extended analysis of exhaled and nasal nitric oxide for the evaluation of chronic cough.

摘要: Abstract Introduction Chronic cough is usually defined as a that lasts for eight weeks or longer. Its etiological diagnosis not always straightforward, and the measurement of exhaled nitric oxide (FeNO) has been proposed in patients' evaluation. No studies have assessed usefulness extended NO evaluation chronic cough. Therefore, we aimed at evaluating an nasal initial Methods We studied 52 non-smoker patients with prolonged lasting more than weeks. Etiologies were identified. Nasal FeNO using multiple single-breath analysis different constant expiratory flow-rates. From fractional concentration measured each flow-rate, total flux between tissue gas phase bronchial lumen (J'awNO), alveolar (C ano ) extrapolated. Results The classified four categories: variant asthma (CVA), nonasthmatic eosinophilic bronchitis (NAEB), upper airway syndrome (UACS) gastro-esophageal reflux disease (GERD). Compared UACS GERD, both J'awNO higher CVA NAEB, no differences found C level among groups. Conclusions Our study suggests potentially useful role did find any additive value performing flow-rates measurements.