A 2-year-old male West Highland white terrier with a 4-month history of seizures was referred for investigation. Depressed mentation, proprioceptive deficit and decreased menace response were noted at neurological examination. Post-mortem examination of the brain revealed multifocal lesions located principally in the left side of the diencephalon and mesencephalon. The lesions consisted of non-suppurative inflammation and large areas of cavitation. The clinical evaluation and histopathological findings were consistent with a diagnosis of necrotizing meningoencephalitis (NME). Immunofluorescence performed on frozen sections of kidney revealed strong smooth linear labelling of the glomerular basement membrane with anti-IgG serum as well as weaker linear labelling with anti-IgM serum. This histomorphological pattern was consistent with anti-glomerular basement membrane glomerulonephritis. The association of this type of glomerulonephritis with a necrotizing encephalitis would support the hypothesis of an immune-mediated aetiology for NME.