Point-of-care blood eosinophil count in a severe asthma clinic setting

Background One of the main severe asthma phenotypes is severe eosinophilic or eosinophilic refractory asthma for which novel biologic agents are emerging as therapeutic options. In this context, blood eosinophil counts are one of the most reliable biomarkers. Objective To evaluate the performance of a point-of-care peripheral blood counter in a patients with severe asthma. Methods The blood eosinophil counts of 76 patients with severe asthma were evaluated by point-of-care and standard analyzers. Results A significant correlation between blood eosinophils assessed by the 2 devices was found (R2 = 0.854, P <.001); similar correlations were found also for white blood cells, neutrophils, and lymphocytes. The point-of-care device had the ability to predict blood eosinophil cutoffs used to select patients for biologic treatments for severe eosinophilic asthma and the ELEN index, a composite score useful to predict sputum eosinophilia. Conclusion The results of our study contribute to the validation of a point-of-care device to assess blood eosinophils and open the possibility of using this device for the management of severe asthma management.