Does tidal exhaled nitric oxide reflect mucosal airway inflammation in infants?

Using transmission electron microscopy, the numbers of subepithelial eosinophils, neutrophils, mast cells, plasma cells, and lymphomononuclear cells, identified by their ultrastructure, were determined in ultrathin sections obtained from the endobronchial biopsies. 3 As there are no reference data in normal healthy infants, we used an arbitrary classification based on the median count of each cell line ( =50th percentile=high). Only the results in atopic infants favoured an association between FENO and eosinophils. [...]although it seems unlikely that FENO,TB would be a useful predictor of corticosteroid responsiveness in unselected infants with severe recurrent respiratory symptoms, its usefulness in selected infants with recurrent wheeze remains to be studied further.