Lung
Other nonneoplastic disease
Alveolar proteinosis
Author: Elliot Weisenberg, M.D.
Last author update: 1 October 2011
Last staff update: 11 December 2024 (update in progress)
Copyright: 2003-2024, PathologyOutlines.com, Inc.
PubMed search: alveolar proteinosis [title] pulmonary
Table of Contents
Definition / general | Treatment | Microscopic (histologic) description | Electron microscopy descriptionCite this page: Weisenberg E. Alveolar proteinosis. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/lungnontumoralveolarprotein.html. Accessed December 25th, 2024.
Definition / general
- Rare disease with accumulation of acellular surfactant presumedly due to impaired clearance, likely due to dysfunction of alveolar macrophages
- Considered a response to alveolar injury, not a specific entity
- Congenital (2% of cases), primary (idiopathic) or secondary forms
- Congenital cases are usually due to mutation in surfactant protein or GM-CSF receptor genes
- Secondary (most common), associated with silica dust, aluminum, fiberglass, chemicals, immunosuppression, leukemia / lymphoma, Nocardia, Mycobacteria and Aspergillosis
- Usually adults (more common in smokers), also children
- Sputum contains chunks of gelatinous material; no inflammation
- Usually does NOT progress to chronic fibrosis
- Xray: resembles pulmonary edema; diffuse pulmonary opacification
Treatment
- Whole lung lavage (also diagnostic)
Microscopic (histologic) description
- Alveoli contain amorphous, eosinophilic and PAS+ material in lumina consisting of type II pneumocytes, lamellar bodies and necrotic alveolar macrophages
- Variable fibrosis
- Mild / no lymphocytic infiltration
Electron microscopy description
- Exudate contains lamellar bodies, lipid particles and cellular debris
