External hydrocephalus in a dog with suspected bacterial meningoencephalitis.

An approximately 12-week-old, male fox terrier was presented for clinical and physical signs consistent with hydrocephalus. Diagnostic evaluation led to a diagnosis of external hydrocephalus and fibrinopurulent meningoencephalitis. Treatment consisted of antibiotics and the placement of a ventriculoperitoneal shunt. The dog improved neurologically and was alive and doing well 1 year following initial presentation. This is the first reported case of external hydrocephalus in the dog. The dog of this report exhibited clinical features consistent with a disorder termed hydrocephalus with periventricular encephalitis.