Gao J, et al. - Researchers investigated the clinical application of the correlation between sputum eosinophils, fractional exhaled nitric oxide (FeNO) and blood eosinophils with uncontrolled asthmatic patients. They also assessed the links between these biomarkers in bronchial reversibility and bronchial hyper-responsiveness (BHR). They found that blood eosinophils and FeNO could provide an accurate prediction of eosinophilic airway inflammation in uncontrolled asthmatic patients. For sputum neutrophils and blood eosinophils, FeNO was identified to be poor surrogates. The FeNO level and blood eosinophils were shown to determine an optimal cutoff for sputum eosinophilia.