[A case of pulmonary alveolar proteinosis with increased IgE and CEA]

We report here a case of pulmonary alveolar proteinosis with significantly increased IgE and CEA values, in both serum and bronchoalveolar lavage fluid. A 35-year-old man presented with exertional dyspnea, diffuse abnormal shadows on radiological examination of the chest and physiologic evidence of a restrictive lung disease. Bronchoalveolar lavage and transbronchial lung biopsy proved that the patient was suffering from pulmonary alveolar proteinosis. He had worked as a landscape gardener for the past 2 years, and had been exposed to insecticides. IgE and CEA levels were significantly elevated in both serum and bronchoalveolar lavage fluid. After whole lung lavage, general status improved remarkably and serum CEA fell to the normal range. The serum IgE level was, however, reduced by only half. Proliferating type II epithelial cells in pulmonary alveolar proteinosis have been suggested to produce CEA. However, the cause of the increased IgE level remains unknown. This case report suggests that some abnormal immunological events, leading to hyperproduction of IgE, could play a role in the onset of pulmonary alveolar proteinosis.