EXHALED NO PICKS UP EARLY CHILDHOOD ASTHMA

Exhaled NO (FE_NO) is an important non-invasive marker of airway inflammation in asthma and probably reflects eosinophilic inflammation. In this issue of Thorax, Malmberg and colleagues show us that FE_NO is particularly useful in identifying preschool children with asthma. The authors studied children with asthma and matched healthy non-atopic controls. As expected, children with probable asthma had raised levels of FE_NO, but children with chronic cough who had normal lung function also had raised FE_NO levels. This study shows that FE_NO is superior as an inflammatory marker in discriminating between probable asthmatics and normal children, with loose associations described between the exhaled marker and lung function. The authors also point out the important observation that airway inflammation is a feature in the early stages of asthma, even in children. See page494 …