Pulmonary alveolar proteinosis
Pulmonary alveolar proteinosis is a rare disease in which a type of protein builds up in the air sacs (alveoli) of the lungs, making breathing difficult.
Alveolar proteinosis; Pulmonary alveolar phospholipoproteinosis
In some cases, the cause of pulmonary alveolar proteinosis is unknown. In others, it occurs with lung infection or an immune problem. It also can occur with cancers of the blood system, and after exposure to high levels of environmental substances, such as silica or aluminum dust.
This rare disorder generally affects people ages 30 to 50 and is seen in men more often than in women. A form of the disorder is present at birth (congenital).
There may be no symptoms.
Exams and Tests
The doctor may hear crackles ("rales") in the lungs. Often, the physical examination is normal.
The following tests may be done:
Treatment involves washing out the protein substance from the lung (whole-lung lavage) from time to time. Certain patients with this disease may need to have a lung transplant. Avoidance of dusts that might have caused the condition is also recommended.
Research has shown some benefit to an experimental treatment that uses a blood-stimulating medication called granulocyte-macrophage colony stimulating factor (GM-CSF), which is known to be lacking in some patients with alveolar proteinosis.
Some people with this condition go into remission. Others have respiratory
failure that gets worse, and they may need a lung transplant. Up to 25% of people with this condition die within 5 years of being diagnosed.
When to Call a Medical Professional
Call your health care provider if you develop serious breathing symptoms. Shortness of breath that gets worse over time may signal that your condition is developing into a more serious medical emergency.
Levine SM. Alveolar filling disorders. In: Goldman L, Ausiello D, eds. Goldman's Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 91.
Trapnell BC, Nakata K, Kavuru MS. Pulmonary alveolar proteinosis syndrome. In: Mason RJ, Broaddus VC, Martin TR, et al, eds. Murray and Nadel's Textbook of Respiratory Medicine. 5th ed. Philadelphia, Pa: Saunders Elsevier; 2010:chap 63.
Denis Hadjiliadis, MD, Assistant Professor of Medicine, Division of Pulmonary, Allergy and Critical Care, University of Pennsylvania, Philadelphia, PA. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, Bethanne Black, Stephanie Slon, and Nissi Wang.