pulmonary alveolar proteinosis n.
A chronic progressive lung disease of adults characterized by alveolar accumulation of granular proteinaceous material and little inflammatory cellular exudate.
pulmonary alveolar proteinosis
respiratory disorder caused by the filling of large groups of alveoli with excessive amounts of surfactant, a complex mixture of protein and lipid (fat) molecules. The alveoli are air sacs, minute structures in the lungs in which the exchange of respiratory gases occurs. The gas molecules must pass through a cellular wall, the surface of which is generally covered by a thin film of surfactant material secreted from the alveolar cells. When too much surfactant is released from the alveolar cells, or when the lung fails to remove the surfactant, gas exchange is greatly hindered and the symptoms of alveolar proteinosis occur.
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