Central Nervous System Inflammation


Central Nervous System (CNS) inflammation is a common cause of neurological disease in cats and dogs.

The term meningitis is used when the lining surrounding the CNS is affected. The terms encephalitis and myelitis refer to inflammation of the brain and spinal cord, respectively.


Dogs and cats with CNS inflammation can exhibit a variety of abnormalities. These may include behavioral changes, weakness, abnormal limb coordination, blindness, and seizures. Some animals have signs that develop over weeks or months, whereas others appear to be suddenly affected.


There are many diseases that can mimic CNS inflammation such as tumors, strokes, malformations, and metabolic abnormalities. Appropriate testing is required to diagnose CNS inflammation and determine the type of inflammatory disease.

Animals suspected of CNS inflammation usually receive blood cell counts, blood chemistry tests, nervous system imaging, spinal fluid evaluation, and testing for infectious disease. Magnetic resonance imaging (MRI) is the preferred means of imaging the CNS. An MRI provides clear pictures of the brain and spinal cord and is the only way to diagnose many diseases that can mimic CNS inflammation, such as stroke.

Research performed at Texas A&M University, the University of Georgia, and elsewhere has highlighted that the majority of dogs with CNS inflammation do not have an active infection at the time of diagnosis. Most dogs appear to have abnormal immune system responses, which result in the disease process. Animals with immune-based CNS inflammation typically require drugs that slow down the immune system.


With properly tailored treatment these animals can live for years with excellent quality of life. Cats with CNS inflammation often have an active infection and may respond to treatment with antibiotics or other drugs.

Some animals with CNS inflammation can have seizure disorders. Although seizures can be distressing to owners, they can usually be controlled (but not entirely eliminated) with medications. Newer anti-seizure drugs are easy to use and likely have fewer side effects when compared to older standard medications.

Finally, animals with CNS inflammation may require intensive care unit-type care if they are severely affected. Treatments may need to be administered that can decrease brain swelling and lower the pressure within the skull.

Intravenous treatments to suppress the immune system may also be required. Round the clock nursing care, board-certified critical care specialists, and access to a team of specialists can be essential in giving the patient the best chance for recovery.

Most Frequently Affected Breeds

  • Yorkie
  • Pug
  • Chihuahua
  • Maltese