Hydrocephalus with periventricular encephalitis in the dog.

A 3-month-old female Dalmatian dog and a 2.5-month-old Poodle dog were referred with a sudden onset of neurological syndrome consistent with hydrocephalus. Clinical signs included depression, severe ataxia, eye abnormalities and skull enlargement in one case. Postmortem examination revealed severe internal hydrocephalus with cavitation of the cerebral white matter associated with necrotizing and inflammatory lesions of the periventricular nervous tissue. Although no bacteria were isolated from cerebrospinal fluid and no infectious agents were detected in the brains, an infectious etiology was postulated.