A 47-year-old woman was admitted to our hospital because of dry
cough and throat discomfort. Chest
X-ray film showed reticular shadows with Kerley B line and scattered nodular shadows. Blood examination revealed normal WBC count (5100/mm3) with
eosinophilia (21%), negative CRP, elevated ESR (49 mm/l hr), normal
IgE level and positive
antinuclear antibody with speckled pattern. Skin tests and precipitating
antibodies for common
allergens were negative. Results of arterial blood gas analysis and respiratory function test were almost normal. Bronchoalveolar lavage fluid yields 85.7% eosinophils, which suggested eosinophilic
lung disease. To establish the diagnosis,
thoracotomy was performed and lung specimens were obtained from S3a and S8a. In the area of the nodule, the alveolar spaces were filled with eosinophils and mononuclear cells, with no evidence of
vasculitis,
granuloma or parasites. Alveolar spaces were almost preserved in residual areas. The walls of air ways, pleura and lobular septa were heavily infiltrated with eosinophils and mononuclear cells. Thus, open lung biopsy confirmed the diagnosis of idiopathic
eosinophilic pneumonia. The areas of intraalveolar filling with eosinophils and mononuclear cells were found to correspond to the nodular shadows on chest
X-ray film. The relationship between the findings of chest
X-ray films and lung histology are discussed.