Orally exhaled nitric oxide as a marker of inflammation in childhood asthma

Airway inflammation is a key process involved in asthma since mediators released by inflammatory cells may induce acute damages and structural changes to the airways. Airway inflammation is, therefore, a primary therapeutic goal and the treatment with anti-inflammatory drugs should be started as early as possible in order to avoid irreversible airway remodelling occurring during chronic inflammation, even in young children. The need to monitor inflammation has led to the exploration of volatile compound in exhaled air. Nitric oxide (NO) is being increasingly used to assess airway inflammation in childhood. Moreover, it has become clear in the last few years that increased NO is present in the expired air of patients with asthma and that measurement of the fractional concentration of exhaled NO (FE_NO) may represent a non invasive, simple, well tolerated test thought to reflect the airway inflammatory events in asthmatic children.