Update on exhaled nitric oxide in pulmonary disease

Abstract

The ability to assess the inflammatory status of a patient’s airway using a noninvasive method is the ideal situation for clinicians. Owing in part to the relationship between the levels of exhaled nitric oxide to inflammation and the ease of the technique, the measurement of the fraction of exhaled nitric oxide (F_ENO) has achieved considerable attention, particularly with respect to asthma. A multitude of studies have shown that when measured in exhaled air, this unique molecule has the potential to have both diagnostic and therapeutic roles in the clinical setting for many pulmonary diseases. The incorporation of F_ENO into asthma management and treatment algorithms may help shed further insight on the current control and future risk of patients. Research is ongoing to determine the biology and the benefits of the use of F_ENO in respiratory conditions in addition to asthma. This review will briefly outline the pathophysiology of nitric oxide, the measurement of F_ENO and the potential clinical uses of F_ENO in asthma and a number of other respiratory diseases. Despite its promise, until further research is conducted, the use of F_ENO cannot be recommended for routine clinical management of respiratory diseases at present, but should be considered as an adjuvant to help guide therapy in certain patients with asthma and in those with eosinophilic bronchitis.

Keywords::

• asthma
• eosinophilic bronchitis
• exhaled nitric oxide
• F_ENO
• fraction of exhaled nitric oxide
• inflammation

Financial & competing interests disclosure

RA McIvor has received honoraria for providing lectures and attending advisory boards in asthma management for AstraZeneca, GlaxoSmithKline, Merck, Norvartis and Boehringer Ingelheim. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.