Chronic eosinophilic pneumonia presenting with acute onset

A 44-year-old woman was hospitalized with a 2-day history of cough, sputum, and fever. There was no history of atopic dermatitis or asthma. On admission, the chest X-ray revealed scattered infiltration in the left upper lung fields. Further examination revealed peripheral blood and bronchoalveolar lavage fluid eosinophilia. Transbronchial lung biopsy revealed eosinophilic pneumonia, with eosinophil infiltration of the alveoli, destroyed basal lumina, and connecting intraluminal fibrosis of the alveolar walls. Based on the findings, we made the diagnosis of chronic eosinophilic pneumonia. Treatment with prednisolone at 60 mg/day resulted in dramatic improvement of both the symptoms and the radiologic abnormalities.