Acute eosinophilic pneumonia caused by passive smoking

Acute eosinophilic pneumonia (AEP) is characterized by eosinophilic infiltration in the lungs, respiratory distress, a rapid therapeutic response to corticosteroids, and the absence of relapse. Some cases of AEP are caused by infections, drugs, and inhaled antigens. Cigarette smoking is considered a probable cause of AEP, as AEP has developed soon after starting to smoke in some patients and a challenge with cigarette smoking was positive in some patients. All reported patients with cigarette smoking‐induced AEP were active smokers, while no case of AEP caused by passive smoking has been reported. We present a case of AEP presumed to have been caused by passive cigarette smoking. (Korean J Med 77:508-511, 2009)