Diagnosis
We are using diagnostic tests to determine what the underlying cause of your pet’s symptoms are. A lot of different diseases, ranging from cancers to infections can look the same way!
We always start with a basic blood panel/urinalysis – this is important for any sick pet (not to mention for the monitoring of healthy elderly pets). A basic blood panel and urinalysis is the first step in evaluating the issue and determining what medications should be used. It can also help us in determining if other systems are involved.
X-rays of the heart/lungs and the belly are also helpful in making sure there are no obvious systemic diseases that could be causing the abnormal signs. They are also helpful in determining if it is safe (although there are always risks) to put the patient under anesthesia.
MRI (magnetic resonance imaging) is able to image the brain and spinal cord to help us determine likely causes and, therefore, the most appropriate treatments. CT is typically not helpful for imaging the brain and spinal cord for diseases like this because it focuses more on bone. MRI is considered best modality to evaluate the nervous system because it helps us evaluate soft tissue. General anesthesia is required to do an MRI and spinal tap, as the patient must be perfectly still throughout.
MRI of a dog with brain abnormalities; a biopsy is necessary to determine definitive diagnosis for GME
Collection and analysis of the cerebrospinal fluid (spinal tap) is usually very helpful in the determining/ruling out underlying causes and can also help with prognosis. Prior administration of cortisone-type medication may reduce the cells found in the tap and must be considered by the neurologist in the interpretation of the tap.
This kind of testing also helps in ruling out other conditions that might present similarly:
- Viral encephalitis (including canine distemper and rabies) though further spinal fluid testing is generally more revealing.
- Parasitic encephalitis (such as toxoplasma and neospora)
- Fungal encephalitis (such as Cryptococcus neoformans and others)
- Cancer
***The only way to confirm GME or some cancers with 100% certainty is with a biopsy. However, diagnostics do not get any more invasive than brain surgery. For this reason, confirmation is frequently post-mortem. Again, this is the same reason why you may find that this disease carries a poor prognosis if you are researching for it on the internet. In reality, 70-80% of Dr. Kube’s patients with inflammatory brain and spinal cord disease do very well with minimal treatments (1-2 drugs) and about 50% of those patients come off all medications. Another 10-15% may require 3 or more medications and may do OK requiring increasing medications. There is a small percentage that may not do well despite all the treatment we give. Please remember, some of the numbers are skewed based on the willingness of the owners to treat aggressively and the costs involved in doing so.
