[Fractional exhaled nitric oxide and its correlation with bioptic results in chronic cough patients]

Chronic non-productive cough in non-smokers with negative thoracic X-ray and normal spirometry is frequently encountered problem in the out-patient departments of specialists both pneumologists and allergologists. A lot of those patient present with already ongoing treatment with inhaled steroids. This work attempted to find valid markers of inflammation in our group of patients.

ICS naive non-smokers with negative X-ray of the chest, ACE-inhibitors non-users with no signs of UACS have been examined by bronchoscopy and FENO (Fractional Exhaled Nitric Oxide). Combination of these two methods aimed to confirm or exclude presence of bronchial inflammation. Recommendation for treatment with ICS can be more valid if based on positive results. Very small number of patients with eosinophilic type of bronchial inflammation on biopsy (3 from total no. 48) was found. In the group of those 3 patients with positive finding of eosinophilia in mucosa - regarding changes there were also high values of FENO, whereas in all other "allergy negative" patients the FENO values were low.

There was a low incidence of eosinophilic inflammation in our group of chronic cough patients. Bronchoscopy and FENO were in good agreement in ruling out or in confirmation of eosinophilic inflammation. FENO appears to be a good discriminator for ICS treatment decision in our group of patients.