Lipoid pneumonia in a rough collie dog

The incidence of lipoid pneumonia in dogs is not known and confirmed cases do not appear to have been reported. Three forms of lipoid pneumonia are recognised in mammalian species; exogenous lipoid pneumonia (ELP), endogenous lipoid pneumonia (EnLP), and post-obstructive endogenous lipoid pneumonia (PEnLP). All forms share similar microscopic characteristics of fat accumulation in the cytoplasm of alveolar macrophages and are otherwise clinically indistinct from other forms of pneumonia. A case of lipoid pneumonia in a seven-year-old rough collie dog which was presented with recurrent bronchopneumonia over several months is reported here. Diagnosis was made from biopsy of resected lung tissue and from detection of fat-containing vacuoles in macrophages obtained by bronchoalveolar lavage. ELP could not be differentiated from PEnLP in this dog, but a complete recovery followed removal of the affected right accessory and caudal lung lobes.