Necrotizing meningoencephalitis of Maltese dogs.

The clinical and pathologic features of five young Maltese dogs with a necrotizing meningoencephalitis were studied and compared with published reports of the necrotizing meningoencephalitis of Pug dogs. The ages of the Maltese dogs ranged from 9 months to 4 years. Four dogs were male, and one was female. The dogs had a history of seizures with or without other neurologic signs for 3 days to 20 weeks prior to death. Cerebrospinal fluid examination in three dogs revealed a pleocytosis and elevated levels of protein. At necropsy, the cerebrum was asymmetrically swollen in four dogs, with a loss of distinction between the gray and white matter and mild to moderate asymmetrical dilation of the lateral ventricles. Histologically, there was extensive necrosis and nonsuppurative inflammation of the cerebral gray and white matter, overlying meninges, and adjacent thalamus and hippocampus. The 4-year-old dog had the longest duration of clinical signs and had little inflammation but extensive atrophy of affected areas, with astrocytosis. The clinical course and pathologic changes in these Maltese dogs are indistinguishable from those in reported cases of necrotizing meningoencephalitis of Pug dogs, indicating that this lesion is probably not unique to Pug dogs.