A case of idiopathic hypereosinophilic syndrome presenting with acute respiratory distress syndrome.

Although idiopathic hypereosinophilic syndrome(IHES) commonly involves the lung, it is rarely associated with acute respiratory distress syndrome (ARDS). Here we describe a case of IHES presented in conjunction with ARDS. A 37-year-old male visited the emergency department at Samsung Medical Center, Seoul, Korea, with a chief complaint of dyspnea. Blood tests showed profound peripheral eosinophilia and thrombocytopenia. Patchy areas of consolidation with ground-glass opacity were noticed in both lower lung zones on chest radiography. Rapid progression of dyspnea and hypoxia despite supplement of oxygen necessitated the use of mechanical ventilation. Eosinophilic airway inflammation was subsequently confirmed by bronchoalveolar lavage, leading to a diagnosis of IHES. High-dose corticosteroids were administered, resulting in a dramatic clinical response.