Case of the Month: Seizures

Marley’s story*

While travelling with his family in the United States, Marley suffered what his humans worried was a seizure.  He recovered uneventfully, but when another similar event happened about a week later, he was brought to a local emergency clinic.  Marley had no history of a head trauma, so a comprehensive workup was performed to rule out internal illnesses, endocrine disorders, infections, and poisoning. All of his test results were normal.  Again, Marley recovered well from the event, so he was released into the watchful eyes of his family.  Upon returning home to Canada, Marley continued to have seizures approximately every other week.

Marley was referred to a neurology specialist to attempt to understand the cause of his ongoing seizures. He received repeat blood tests, a CT scan, a spinal tap, and several other tests to screen for Lyme disease and other infections that are known cause neurological disorders.  Although no detectible cause could be found, Marley continued to have seizures.  It was concluded that Marley either had idiopathic epilepsy (an electrical disorder of the brain), or that he had suffered some kind of neurological insult (trauma, toxin, infection) that caused lasting effects, but left no trace behind.

Marley was placed on an anticonvulsant medication long-term to help manage his seizures.  His blood is monitored regularly to ensure that he is tolerating the medication well.

About the Condition: Seizures

Seizures represent an abnormality in how biological electrical signals are produced and travel through the brain.  They can result in lost or altered consciousness, tremors or convulsions, vocalization, stargazing, and temporary loss of continence.  Frequent, prolonged, or severe seizures can cause permanent brain damage, blindness, and even death. 

Seizures can be caused by things that happen OUTSIDE of the brain, like blood sugar abnormalities, hormonal disturbances, or poisoning. They can also be caused by things happening INSIDE the brain, like tumors, strokes, head trauma, or infection.  Sometimes causes are categorized as structural (actual physical changes within the brain), or non-structural.  Structural diseases like tumors, strokes, and scars are more common in older patients, and known to be more difficult to manage with medication.  When no toxin, structural abnormality, or blood abnormality can be identified, seizures are classified as Idiopathic Epilepsy…seizures with unknown cause.  Idiopathic epilepsy is usually the easiest kind of epilepsy to control with medication, and is the most common form of epilepsy diagnosed in dogs who have their first seizure at a young age (under five).

Sometimes a seizure is a one-off event.  When seizures happen more than once, especially within a three-month period, it’s important to investigate the cause.  This involves examining the animal thoroughly, asking the owner about diet, drug/toxin access and other lifestyle features, and running both basic and advanced diagnostic tests.  Bloodwork can rule out blood sugar and electrolyte abnormalities, organ dysfunction and hormonal problems.  Imaging such as MRI or CT scans can screen for structural changes or signs of trauma. Sampling the cerebrospinal fluid (spinal tap) can reveal inflammation or infection within the brain.  When the results of all tests are normal, a diagnosis of idiopathic epilepsy can be made.

Treatment

The goals of treating Idiopathic epilepsy are to prevent severe seizures, to prevent seizure events from escalating, and to reduce seizure frequency to fewer than one event every three months. Treatment involves giving medication that slows or reduces electrical transmission in the brain. This reduces the frequency and severity of seizures but can also cause sedation and sluggishness in the pet, especially in the early weeks of treatment. In a crisis, sedatives like diazepam (Valium), levetiracetam, or even anesthetic drugs like propofol can be given to halt a long-lasting seizure.  Once a pet is stabilized, they are started on daily oral anticonvulsant medications such as phenobarbital, potassium bromide, or levetiracetam (Keppra).  Some dogs “outgrow” epilepsy and can be weaned off medication after 12 or more seizure-free months.  Other dogs require medication to be given life-long to prevent them from having frequent and/or severe seizures.  Medications like phenobarbital can have negative impacts on the liver, so regular bloodwork is necessary to monitor organ function and blood concentrations of the drug. The prognosis for dogs receiving regular monitoring and care for idiopathic epilepsy is good.

Claim Outcome

Marley is doing well on his medication, and experiences fewer, and less severe seizures now, allowing him to return to his active life with his family.  Workup and management of his seizures cost his family $10,250** over a 7 month timeframe since his first episode. Pets Plus Us has reimbursed them $8,100 of those expenses.  We can tell you are in good hands, Marley!