Central Texas Veterinary Specialty Hospital

Non-Infectious Inflammatory Brain Disease

Diagnosis and treatment of neurological disease is often both challenging and frustrating. Signs of intracranial disease are highly variable and can range from subtle behavioral changes to generalized seizures. Inflammatory brain disease should be considered in any patient presenting with seizures, blindness, behavioral change, or disequilibrium.

Inflammatory what?!

Inflammation is a relatively generic term used to describe the body’s reaction to an adverse stimulus. Meningoencephalitis implies inflammation of the brain parenchyma and the surrounding membranes and results from 2 major causes: infectious and non-infectious causes.

There are several, well described forms of non-infectious brain inflammation recognized in dogs including necrotizing meningoencephalitis (NME), necrotizing leukoencephalitis (NLE), and granulomatous meningoencephalitis (GME). Collectively, these diseases usually affect young to middle-aged, small breed dogs.

NME typically affects the grey/white matter junction of the cerebral cortex and can lead to cavitations in the brain tissue. This pattern of inflammation was previously referred to as "Pug dog encephalitis" but has now been recognized in many breeds (including Maltese, Pekingese, and Chihuahua).

NLE typically affects the deep white matter of the cerebrum and brainstem and often results in marked cavitations in the brain. This is often referred to as "necrotizing encephalitis of Yorkshire Terriers" but has described in several breeds (including Chihuahuas and French bulldogs).

GME is probably the most well known of the non-infectious inflammations of the brain. Although often seen affecting the brainstem, this disease can present with highly variable signs and can be seen in ocular, focal, or disseminated forms.

The definitive diagnosis of inflammatory brain disease is ultimately through histopathology. The combined use of magnetic resonance imaging (MRI) and cerebrospinal fluid analysis has enabled us to make more accurate antemortem diagnosis of these diseases. MRI is the best diagnostic modality available to image the brain and allows us to see the exact nature and location of these lesions. Knowing where these diseases typically affect the brain, and being able to see them with MRI, can help us establish an accurate antemortem presumptive diagnosis and begin treatment as quickly as possible.

The CTVSH neurology department is available at our Round Rock location for consultation and full diagnostic workup. We offer in-house 1.5T MRI and CSF analysis. Please feel free to call CTVSH with any questions.