a very rare disease in which a phospholipid is widely distributed in cells and accumulates in the alveolar spaces in the lung. In some cases the underlying cause is unknown. In others it may relate to an infection or an immune system dysfunction. The net effect is a progressive interference in the ability of the lung (alveoli) to exchange oxygen and carbon dioxide.
symptoms include cough, weight loss, fatigue, shortness of breath and nail abnormalities (clubbing). Chest x-ray may show infiltrates, but a bronchoscopy with trans-tracheal biopsy is necessary to make a tissue diagnosis or alveolar proteinosis. Spontaneous remission may occur in some individuals while complete respiratory failure occurs in others.