Introduction to Inflammatory Brain Disease in Dogs

Inflammatory Brain Disease encompasses a range of conditions, including Granulomatous Meningoencephalitis (GME) and Necrotizing Encephalitis (NE). These diseases are often grouped together because distinguishing the specific type a dog has generally requires a brain biopsy. However, since they present similarly, share treatment approaches, and have comparable prognoses, a brain biopsy is usually not recommended. Instead, treatment is initiated based on clinical diagnosis.

This condition is sometimes referred to as Meningoencephalitis of Unknown Etiology (MUE), as the exact cause remains unknown. However, genetic predispositions have been identified in certain breeds. For example, a specific gene (DLA) in Pugs has been linked to a significantly higher risk of developing this disease. Genetic testing for this gene can be arranged during your appointment.

Ultimately, Inflammatory Brain Disease appears to be an autoimmune disorder, where the immune system mistakenly attacks the brain as if it were an infectious agent, despite the absence of an actual infection. This process is somewhat analogous to multiple sclerosis in humans.

Steroid Responsive Meningitis Arteritis is also an inflammatory disease that can affect the brain, however due to some differences in diagnosis and prognosis, it is discussed in another section.

Which Dogs Are Prone to Inflammatory Brain Disease

Inflammatory Brain Disease primarily affects small breed dogs, including Pugs, French Bulldogs, Yorkshire Terriers, and Chihuahuas. However, it's important to note that this condition can occur in dogs of any breed and, though very rare, it can also affect cats. The majority of cases are diagnosed in dogs aged between 2 and 7 years.

Symptoms of Inflammatory brain disease

If you notice the onset of new symptoms or worsening of existing ones in your pet, it’s important to consult with the neurology team. These symptoms can be indicative of various brain diseases, so unless your pet has been specifically diagnosed with Inflammatory Brain Disease through an MRI and spinal tap, these signs don't definitively point to this particular condition.

Common symptoms include:

Seizures
Changes in personality
Loss of training or previously learned behaviors
Difficulty staying awake or sleeping
Problems with walking or coordination
Dizziness or vertigo
Circling behavior
Sudden onset of blindness
Challenges with eating, drinking, or swallowing

Diagnosing Inflammatory Brain Disease

The diagnosis of Inflammatory Brain Disease typically involves an MRI, a spinal tap, and specialized blood work to exclude infections. While identifying specific conditions like Granulomatous Meningoencephalitis (GME) or Necrotizing Encephalitis (NE) would require a brain biopsy, this procedure is not commonly recommended due to practical considerations. Therefore, to ensure an accurate diagnosis, it’s essential to perform as many supportive tests as possible, such as CT/MRI scans, cerebrospinal fluid (CSF) analysis, and infectious disease testing. These comprehensive evaluations help us confidently determine the presence of Inflammatory Brain Disease in your pet.

Will my pet be okay?

Inflammatory Brain Diseases are serious conditions, and it is a sad reality that despite treatment, some dogs may not survive. However, many dogs respond positively to treatment and have a good quality of life. In some cases, dogs can even be cured of the disease. It's important to understand that while there is hope for improvement, a complete cure is not always possible and some dogs may be on medication for the rest of their lives.

Treatment of Inflammatory Brain Disease

Inflammatory Brain Disease is primarily treated with immunosuppressive drugs. While there are various treatment protocols, most include the use of steroids such as prednisone or dexamethasone. Additionally, many dogs are prescribed a second medication to regulate the immune system. This combination allows for reduced steroid use over time, which is beneficial given the potential serious side effects of long-term or high-dose steroid use. Other medications that may be recommended include cytarabine, mycophenolate, leflunomide, cyclosporine, azathioprine, and CCNU.

It's important to note that these drugs can weaken your pet's ability to fight infections, and vaccinations might not be advisable during treatment. If your dog experiences seizures, seizure medications will likely be part of the treatment plan.

Regular veterinary check-ups are crucial for monitoring your pet's health. Typically, rechecks are scheduled 1-2 weeks after the initial diagnosis and then monthly for the first few months. The frequency of further rechecks depends on the severity of your dog's condition; more severely affected dogs may require hospitalization initially and more frequent check-ups. Regular blood and urine screenings are advised to monitor for medication side effects. For stable patients, we recommend these tests every 4 months.

If your pet exhibits any of the following symptoms, it is crucial to seek emergency veterinary care immediately:

If your pet has any of the following signs, please seek emergency care:

Experiencing more than two seizures in a day, unless your veterinary team has provided specific alternate instructions.
A seizure that lasts longer than five minutes.
Inability to stand or walk.
Difficulty or inability to eat or drink.
Unconsciousness, especially if your pet cannot be roused.
Pressing their head against a wall or other surfaces persistently.
Continuous howling, barking, or crying that does not subside when comforted.
Sudden, uncharacteristic aggressive behavior.

Inflammatory Brain Disease