[Acute eosinophilic pneumonia induced by cigarette smoking--a challenge test utilizing another brand of cigarette]

A 15-year-old boy was hospitalized with complaints of fever, dry cough, and dyspnea. Chest X-ray films demonstrated diffuse infiltrates with peripheral dominance and blood gas analysis disclosed hypoxemia. Examination of bronchoalveolar lavage fluid revealed an increased eosinophil count. Transbronchial lung-biopsy specimens revealed the infiltration of eosinophils into alveolar walls. A conclusive diagnosis of acute eosinophilic pneumonia (AEP) was made on these grounds. We suspected the disease was associated with smoking because the patient had begun smoking cigarettes two weeks before admission. A challenge test was performed using a cigarette brand different from the one the patient had smoked, and was positive. Our findings supported the view that cigarette smoking in general can be a cause of AEP.