Meningitis in Dogs

Meningitis is an uncommon, potentially life threatening condition that refers to inflammation of the meninges. Meninges are membranes that cover the brain and spinal cord. Any pet that is showing signs of seizures, changes in mental state or ability, or generalized pain needs to be examined by a veterinarian as soon as possible.

Meningitis is rare in dogs. Since there are numerous possible causes, it is difficult to identify specific risk factors. Very old, very young, and immunocompromised individuals are at increased risk of infections, which may increase the risk of meningitis.

Unvaccinated dogs and dogs who are not on regular parasite control are at higher risk of specific viral and parasite infections, which can lead to meningitis in some cases.

Symptoms may be vague and non-specific initially and worsen as time goes on.

Meningitis is often fatal even with treatment. Any sudden onset of neurologic symptoms, including seizures, incoordination, lack of balance, or involuntary eye movements must be treated as a medical emergency.

Meningitis has many infectious and noninfectious causes.

Infectious meningitis usually occurs through:

• Bite wound
• Inner ear infection
• Contaminated spinal tap

Broad categories of infectious agents include viral, bacterial, fungal, protozoal, parasites, ameboid, and algal agents.

Non-infectious causes of meningitis are broken down into immune mediated or unknown. Steroid responsive meningitis (SRM) is the most common type of non-infectious meningitis and is an immune mediated disorder.

Symptoms vary greatly depending on what area of the central nervous system is affected and the underlying cause.

Altered mental state is also a common symptom, meaning the pet seems disoriented or fails to interact with people or their surroundings like they used to.

Diagnosis starts with a physical exam, blood work, and X-rays. Fluid analysis and culture of the cerebral spinal fluid (spinal tap) is needed in most cases. An MRI of the central nervous system and testing for specific underlying causes are also helpful. Most definitive diagnoses are made after death.

Treatment varies widely and depends on the cause. Specific treatment for the underlying cause and supportive care is required for all cases. Antibiotics or steroids are used most commonly. Supportive care varies based on the severity of symptoms and can include IV fluid therapy, bladder expression or catheterization, rotation of recumbent patients, anticonvulsants, and pain medications.

Repeat analysis of cerebrospinal fluid or MRI is important in deciding when to stop treatment.

Dogs typically undergo treatment for at least 4 weeks. Treatment is continued for 10-14 days past resolution of clinical symptoms.

Prognosis varies from good to grave depending on the underlying cause. Prognosis for steroid responsive meningitis is generally good while most infectious causes carry a poor to grave prognosis.

Some infectious types of meningitis can be prevented by staying up to date on vaccinations and parasite control. Most underlying causes of meningitis cannot be prevented.

Viral causes of meningitis are contagious and are usually spread through aerosolized droplets or transfer of body fluids. Vaccines against viral causes of meningitis are effective at preventing the disease.

Meningitis is uncommon in dogs.

• Antibiotics
• Steroids
• Pain medications
• Supportive care