Endogenous lipid pneumonia associated with atherosclerosis in a blue-fronted Amazon parrot (Amazona aestiva)

Endogenous lipid pneumonia is a rare inflammatory, non-infectious lung disease characterized by the accumulation of endogenous lipids in alveolar macrophages. It has been associated with bronchial obstruction, chronic lung inflammation, alveolar proteinosis and lipid storage disorders. A 14-year-old female blue-fronted Amazon parrot (Amazona aestiva) presented with intermittent dyspnoea, neurological signs and persistent lipaemia of unknown aetiology. At necropsy, the most relevant gross findings were increased rigidity of the great vessels, lungs with diffuse grey to whitish discolouration of the parenchyma and multifocal small yellowish nodules. Microscopic examination revealed typical lesions of atherosclerosis and severe multifocal accumulation of foamy macrophages filling the parabronchi, which led to a diagnosis of endogenous lipid pneumonia. Although the relationship between dyslipidaemia, atherosclerosis and endogenous lipid pneumonia in birds is not well established, the chronic dyslipidaemia of unknown origin could be involved in the pathogenesis of both the atherosclerosis and the endogenous lipid pneumonia. The present case highlights the need to better understand the relationships between various disorders of lipid metabolism in psittacine birds.