Brain and Spinal Cord Inflammation (Meningoencephalomyelitis, Eosinophilic) in Dogs

Meningoencephalomyelitis in Dogs

Eosinophilic meningoencephalomyelitis is a condition that causes the inflammation of the brain, spinal cord, and their membranes due to abnormally high numbers of eosinophils, a type of white blood cell, in the cerebrospinal fluid (CSF). Often, the increase of eosinophils is in response to a parasite infection, tumor or allergic reaction in the dog.

Although dogs of any age may succumb to eosinophilic meningoencephalomyelitis, Golden retrievers seem to be predisposed to the condition.

Symptoms and Types

Symptoms vary in location and severity, but are often related to the nervous system such as circling, loss of memory, seizures and blindness.

Causes

It is common for the underlying cause to the eosinophilic meningoencephalomyelitis to be idiopathic (or unknown) in nature. Other typical factors associated with this disease include:<

• Allergies (also common)
• Tumors
• Parasite infections
• Fungal infections
• Vaccinations

Diagnosis

You will need to give a thorough history of your dog’s health, including the onset and nature of the symptoms. The veterinarian will then conduct a complete physical examination and several laboratory tests -- such as complete blood count (CBC), blood culture biochemistry profile, and urinalysis -- to help identify and isolate the cause of inflammation.

Blood testing may reveal abnormally high number of eiosinophils in the blood. Biochemistry profiling, for example, may show abnormal liver enzyme activity, indicating parasitic infections. And magnetic resonance imaging (MRI) may reveal tumorous lesions in the dog's brain or spinal cord.

One of the most important diagnostic tests, however, is CSF (or cerebrospinal fluid) analysis. A sample of your dog's CSF will be collected and sent to a laboratory for culturing and further evaluation. In case of idiopathic or allergic causes, abnormally high numbers of eiosinophils are seen in the CSF. Tumors, meanwhile, are generally associated with an abnormally low number of white blood cells along with a small number of eiosinophils in the CSF.

Treatment

Due to the severity of the disease, most dogs with eosinophilic meningoencephalomyelitis will need to be hospitalized. In cases where no underlying cause can be identified (idiopathic), your veterinarian may prescribe steroids for a few weeks to control inflammation. Otherwise, dogs are kept on certain diet and movement restrictions until a cause, and more specific treatment regimen, can be found.

Living and Management

Overall prognosis heavily depends on the underlying cause of the disease. However, prognosis is good if aggressive treatment is conducted quickly -- most dogs will improve within first 72 hours and recover after six to eight weeks.

During hospitalization, your dog is often examined every six hours. Post-treatment, the veterinarian may request that you bring the dog for regular follow-up evaluations.