[Acute eosinophilic pneumonia induced by cigarette smoking: positive lymphocyte stimulation test of a cigarette extract].

A 21-year-old man was admitted to our hospital with high fever, general fatigue and dyspnea. Chest radiography on admission showed diffuse bilateral infiltrate shadows with Kerley's B lines, and a CT scan showed patches of infiltrates with thickened interlobular septa in both lungs. Examination of the bronchoalveolar lavage fluid and the clinical course led to a diagnosis of acute eosinophilic pneumonia. The patient improved without steroid therapy. We suspected that the disease was related to smoking because the patient had started smoking seven days before the onset of the symptoms. Because a lymphocyte stimulation test gave a positive reaction to a cigarette extract, a challenge test was done. After this, the patient had fever and hypoxemia. These findings suggest that cigarette smoking induces acute eosinophilic pneumonia.