Epilepsy simply refers to repeated seizures. Seizures may occur as a one time event in an animal from a variety of causes,
but only if the seizures repeat again and again over a period of time
do we call it epilepsy.
Seizures are a sign of brain disease the same
way a cough is a sign of lung disease. Saying an animal has epilepsy is
like saying it has a chronic cough; it is a sign of a problem which
isn't going away. Anything which damages the brain in the right area
can cause epilepsy. If we can identify the cause of the seizures, say a
brain tumor or a stroke, then we say the pet has symptomatic (or
secondary) epilepsy. That is, the seizures are a symptom of a disease
process we've been able to identify. If we've looked and can't find the
cause, then we call it idiopathic (or primary) epilepsy. The term idiopathic
simply means that we don't know the cause. It may be that the cause has
escaped our attention; for example, a stroke that is too small to
detect with routine brain scans or damage that occurred during
Many of the idiopathic epileptics have inherited epilepsy:
epilepsy caused by a mutation in a specific gene which they inherited
from their parents. Dogs with idiopathic epilepsy frequently begin
seizing at between one and three years of age, and certain breeds are
predisposed to develop epilepsy. A few breeds have proven hereditary
epilepsy, while in most it is just a strong suspicion. One of the goals
of the Canine Epilepsy Project
is to identify genes responsible for epilepsy in dogs. This will allow
us to positively diagnose the hereditary form and take steps to
decrease the incidence of epilepsy in dogs.How common is epilepsy?
Epilepsy is one of the most common neurologic diseases in dogs,
but no one knows for sure just how common it is. Some studies estimate
up to 4% of all dogs are affected. In some breeds, the incidence may be
higher and some families may have up to 14% epileptics. Epilepsy occurs
less frequently in cats and other pets, presumably because they do not
have a hereditary form of the disease.
In order to rule out some
diseases, we would need further tests. If the animal is outside the 1-3
year old range when idiopathic epilepsy typically starts, or has any
abnormalities on examination that hint of a cause, we strongly
recommend such testing. Your veterinarian may refer you to a
neurologist for some of these tests. Even if an animal is within the
"idiopathic epilepsy" age range, we can't be sure it's idiopathic
unless we perform the full compliment of tests.Some of the recommended tests for Epilepsy:
- Glucose tolerance test - to check for hypoglycemia.
- Thyroid panel - 6 tests to check for low thyroid function/hypothyroidism.
- EEG - to see if there are findings suggestive of a lesion (an abnormal EEG is standard with epilepsy, but a vet or a physician will also be able to ell if there is a lesion.
- Cerebrospinal fluid analysis - to look for encephalitis, distemper and other infection.
- Blood test to check for lead poisoning or any other abnormality in the blood
- CT scan or MRI - to look at the condition of the brain
Infection of the brain
(encephalitis) can cause seizures. Canine distemper is the most common
cause of encephalitis in dogs and one of the reasons to keep your pets
current on their vaccinations.
Idiopathic Epilepsy, or IE for short, is used to describe repeated seizures of undetermined origin over time. Some think that IE is strictly an inherited condition, but nobody really knows why it happens to some dogs and not others.
With the increased research into environment, dog food ingredients and sources, and genetics we are hoping to stop all types of epilepsy that can be stopped.
Gene found for Neonatal
Encephalopathy of Standard Poodles
Source: Canine Epilepsy Network
Rev. 25 May 09