Kim HS, et al. – The role of serum eosinophil–derived neurotoxin (EDN), eosinophil cationic protein (ECP), and total IgE as a biomarker of disease severity and relapse in severe recalcitrant atopic dermatitis (AD), had been investigated. A correlation was identified between EDN and the disease severity of AD. Furthermore, EDN seemed to predict relapse in severe recalcitrant AD. For evaluating AD disease activity and a predictor of relapse, the EDN serum level could be considered a candidate molecule as a clinical biomarker.