Choi J, et al. - In this retrospective analysis, researchers assessed if eosinophils could serve as a tool to detect bacterial infection in acute exacerbations of chronic obstructive pulmonary disease (AECOPD) events. They studied medical records for patients who sought admission to Korea University Guro Hospital for AECOPD between January 2011 and May 2017. They concluded that for detecting bacterial infection in AECOPD events, eosinophil counts of less than 2% could be potential indicators. With regard to antibiotic use in AECOPD treatment, eosinophils could, therefore, serve as a reference.