Idiopathic Epilepsy in Cats
Epilepsy is a brain disorder that causes the affected cat to have sudden, uncontrolled, recurring physical attacks, with or without loss of consciousness. When this occurs for unknown reasons, it is referred to as idiopathic epilepsy. Epilepsy is more common in dogs than in cats.
Symptoms and Types
Seizures in cats are usually preceded by a short aura (or focal onset). When this occurs the cat may appear frightened and dazed, or it may hide or seek attention. Once the seizure begins, the cat will fall on its side. It may become stiff, chomp its jaw, salivate profusely, urinate, defecate, vocalize, and/or paddle with all four limbs. These seizure activities generally last between 30 and 90 seconds.
Seizures most often occur while the patient is resting or asleep, often at night or in early morning. In addition, most cats recover from the after effects of the seizure by the time you take the cat to the veterinarian for examination.
Generally, epileptic seizures are first seen in cats between one to four years of age. Behavior following the seizure, known as postictal (after seizure) behavior, includes confusion and disorientation, aimless wandering, compulsive behavior, blindness, pacing, increased thirst (polydipsia), and increased appetite (polyphagia). Recovery following the seizure may be immediate, or it may take up to 24 hours.
In many cases, the cause is unknown. Some cases of idiopathic epilepsy may be genetic in origin.
The two most important factors in the diagnosis of idiopathic epilepsy is the age at onset and the seizure pattern (type and frequency). If your cat has more than two seizures within the first week of onset, your veterinarian will probably consider a diagnosis other than idiopathic epilepsy. If the seizures occur when the cat is younger than one year or older than four years, it may be metabolic or intracrainal (within the skull) in origin. Focal seizures or the presence of neurologic deficits, meanwhile, indicate structural intracranial disease.
Diagnosis will usually start with routine blood testing, including a complete blood cell count, a blood chemistry profile, a thyroid screen, and testing for viruses such as feline leukemia and feline AIDS. A urinalysis may also be recommended by your veterinarian.
Additional testing may involve specialized imaging studies of the brain, such as a CT scan or MRI. An analysis of spinal fluid collected via a spinal tap may be recommended as well.