Meningitis in Dogs: Everything a Pet Parent Needs To Know

Meningitis is inflammation of the meninges, the thin layers of tissue that surround the brain and spinal cord. 

What Is Meningitis in Dogs?

When you read about meningitis in dogs, you might also encounter medical terms that combine the word “meningitis” with other words, such as “encephalitis” or “myelitis.” While these complicated words can be confusing, it’s important to know about these conditions that often go together with meningitis. 

Words ending in “-itis” describe inflammation affecting part of your dog’s body. For example, encephalitis means inflammation of the brain, while myelitis means inflammation of the spinal cord.

Meningoencephalitis refers to inflammation of the meninges that surround the spinal cord and brain and inflammation of the brain itself. 

Understanding these terms can provide valuable insight into what your dog is experiencing when they are affected by these conditions. 

Many conditions can cause inflammation of the meninges, spinal cord, and brain, and all meningitis cases require prompt treatment by a veterinarian. 

If you think your dog may have signs of meningitis, seek emergency veterinary care immediately. 

Symptoms of Meningitis in Dogs

Dogs with meningitis may develop the following signs: 

• Fever 

• Generalized pain (may be severe) 

• Neck stiffness 

• Lethargy 

• Poor appetite 

Dogs can experience different clinical signs depending on which structures are affected by inflammation and swelling. 

With meningitis alone, they typically develop a fever, pain, and often a stiff neck. However, if inflammation extends to the brain or spinal cord, neurological signs can occur. 

If inflammation extends to the brain (meningoencephalitis), affected dogs may experience behavioral changes, confusion, agitation, or seizures. 

If the spinal cord is involved (meningoencephalomyelitis), they may develop coordination issues, unsteadiness, vertigo, and tremors. 

Causes of Meningitis in Dogs

Meningitis is often caused by an infection or autoimmune condition. 

Autoimmune disease occurs when the immune system attacks normal body tissues. The exact cause of autoimmune disease in dogs is unclear, but it may result from a combination of genetic predisposition and environmental triggers that prompt an immune response. 

Autoimmune meningitis cases are often grouped under the term steroid-responsive meningitis-arteritis (SRMA). While this condition is more commonly seen in Beagles, other breeds can also be affected. 

In some cases, meningitis is classified as “idiopathic,” meaning the underlying cause is unknown. 

A good example is granulomatous meningoencephalomyelitis (GME), a condition that primarily affects small toy breeds, such as Poodles and Terrier breeds. 

The following are more common causes of infectious meningitis in dogs: 

• Bacterial infections: Bacterial infections in another part of the body, such as the sinuses, ears, eyes, or a distant organ, can spread to the central nervous system. Tick bites and animal bites can also lead to bacterial meningitis. Pasteurella, Staphylococcus, and Ehrlichia are examples of bacteria that can lead to meningitis. 

• Viral infections: Viral meningitis was more common before widespread vaccination decreased the incidence of canine distemper virus, which can lead to the condition. 

• Fungal infections: Fungi such as Histoplasma, Cryptococcus, Blastomyces, and Coccidioides can be found in the soil and affect the central nervous system. 

• Protozoan infections: Toxoplasma is a protozoan that can invade a dog’s central nervous system and cause meningitis; however, the condition is more common in cats. 

• Parasites: Uncommonly, parasites can lead to meningitis. An example is Baylisascaris, a roundworm found in raccoons. 

How Veterinarians Diagnose Meningitis in Dogs

To diagnose meningitis in dogs, a veterinarian will start with a physical exam and blood work. 

If they suspect meningitis, your vet might recommend special blood, urine, or fecal tests to rule out regional infectious causes. 

In some cases, your veterinarian might refer your dog to a veterinary neurologist for advanced diagnostic testing, such as: 

• Magnetic resonance imaging (MRI): MRI is a non-invasive test that produces a detailed image of soft tissues—in this case, the brain and spinal cord. Dogs must be completely still for an MRI, so it is performed under general anesthesia. 

• Computed tomography (CT): This test takes cross-sectional images to provide a detailed three-dimensional picture of internal structures. 

• Cerebrospinal fluid (CSF) analysis (spinal tap): For this test, a long needle is inserted into the vertebral space to collect a sample of the fluid surrounding the brain and spinal cord. The fluid is then analyzed to diagnose meningitis and possibly determine its cause. A CSF analysis is done under anesthesia. 

Treatment of Meningitis in Dogs

Treatment for meningitis in dogs depends on the underlying cause. 

Some meningitis cases, such as bacterial or fungal infections and steroid-responsive meningitis, are curable. 

Others, such as granulomatous meningoencephalomyelitis (GME), are progressive and have no successful treatment. A veterinarian would then recommend humane euthanasia.  

If a bacterial cause is diagnosed, your dog will be put on antibiotics, such as doxycycline or clindamycin. If your dog is diagnosed with a fungal infection, they might be prescribed antifungal medications, like itraconazole. 

Infections in the brain and spinal cord often require extended treatment and typically require frequent rechecks and monitoring. 

Expect your dog to be on medications for many months or possibly years. 

Steroids, such as prednisone, are often prescribed for dogs with non-infectious meningitis. These dogs also usually require long treatment protocols. While some dogs might be able to stop taking medications, others are tapered down to their lowest effective dose for long-term treatment. 

Recovery and Management of Meningitis in Dogs

While many dogs affected by meningitis make a full recovery, treatment commonly takes many months. Fortunately, many dogs show improvement within days of starting appropriate medications. 

Pain medications, such as gabapentin, might be necessary if your dog is stiff or uncomfortable during the initial recovery phase.

Always consult your veterinarian before giving your dog any medication. 

Deeper bedding, like an orthopedic bed, can help support your dog’s body if they have generalized pain. A wheelchair or other support can be helpful if they are unsteady from inflammation in or around their spine.

Prevention of Meningitis in Dogs

Not all cases of meningitis in dogs can be prevented, but you can lower your pet’s risk by: 

• Ensuring your dog is up to date on their vaccinations 

• Providing year-round tick prevention 

• Preventing your dog from interacting with wildlife 

• Preventing your dog from rooting around in soil that might contain dangerous fungal spores