<unk>  <unk>  is a rare lung disorder characterized by an abnormal accumulation of surfactant-derived lipoprotein compounds within the alveoli of the lung. The accumulated substances interfere with the normal gas exchange and expansion of the lungs, ultimately leading to difficulty breathing and a predisposition to developing lung infections. The causes of<unk>  may be grouped into primary (autoimmune<unk> , hereditary<unk> , secondary (multiple diseases), and congenital (multiple diseases, usually genetic) causes, although the most common cause is a primary autoimmune condition in an individual.
Pulmonary alveolar proteinosis
Cryptogenic organizing pneumonia
Eosinophilic pneumonia
Lipid pneumonia
Acute eosinophilic pneumonia
Parasitic pneumonia
Pulmonary sequestration
Pulmonary alveolar microlithiasis