Table 1

 Respiratory and non-respiratory conditions in which Feno measurements may have a role in diagnosis

Increased FenoVariable changes in Feno reportedDecreased Feno
Asthma1,79 Late asthmatic response80,81 Allergic rhinitis19 Viral infections43,44,82 Hepatopulmonary syndrome83 Liver cirrhosis84,85 Acute/chronic rejection of lung transplant including bronchiolitis obliterans86–90Bronchiectasis91–93 COPD17,75,78,94,95,96,97,98,99,100,101,102 Fibrosing alveolitis103 Sarcoidosis104 Systemic sclerosis105–107Cystic fibrosis91,108–110 Primary ciliary dyskinesia111,112 Pulmonary hypertension113 HIV infection114 ARDS115