Epilepsy

Causes and Risks:
A seizure disorder includes any condition in which there are repeated episodes of seizures of any type. Epilepsy (idiopathic seizure disorder) is a term used when the seizure disorder has no identifiable cause such as brain disease. A seizure disorder affects about 0.5% of the population. It can affect people of any age.

Transmission of information from nerve cell to nerve cell occurs by an electrochemical process. This process can be detected as electrical activity by an electroencephalograph ( EEG ). Abnormal patterns of electrical activity are associated with seizures.

The cause of the seizure correlates to some extent with the age of onset. In some people, seizures may be triggered by hormone changes such as pregnancy or menstruation. They may also be triggered by illness or by sensory stimuli such as lights, sounds, and touch. In many cases, no trigger is found for the seizures. Given sufficient circumstances, any person will have a seizure. The amount of stimulation required to cause a seizure is called the seizure threshold. Many people with epilepsy are considered to have a low seizure threshold.

Some of the more common causes of seizures include:
  • Idiopathic (no identifiable cause)
    • usually begin between ages 5 to 20
    • can occur at any age
    • no other neurologic abnormalities present
    • often a family history of epilepsy or seizures

  • Congenital defects and perinatal (near the time of birth) injuries--seizures usually begin in infancy or early childhood
  • Metabolic abnormalities

  • Brain injury
    • may affect any age, highest incidence in young adults
    • most likely if the brain membranes are damaged
    • seizures usually begin within 2 years after the injury
    • early seizures (within 2 weeks of injury)--do not necessarily indicate that chronic seizures (epilepsy) will develop

  • Tumors and brain lesions that occupy space (such as hematomas )
    • may affect any age, more common after age 30
    • partial (focal) seizures most common initially
    • may progress to generalized tonic-clonic seizures

  • Disorders affecting the blood vessels ( stroke , TIA , and so on)
    • most common cause of seizures after age 60

  • Degenerative disorders (senile dementia Alzheimer type, or similar organic brain syndromes)
    • mostly affect older people

  • Infections

There may be changes in mental status (such as alertness and awareness) and/or focal neurologic symptoms (localized symptoms of changes in brain function) associated with the seizures. The type of seizure that occurs varies depending on the location and type of the problem causing the seizure and with individual response to the problem.

Seizures may occur in a generalized form (affecting all or most of the brain) or in a partial form (affecting only a portion of the brain). Epilepsy is typically generalized (except in some cases that develop in childhood and have a specific focus). Generalized seizures include variations of generalized tonic-clonic seizures and petit mal seizures . Partial seizures include focal seizures (during which the person remains alert but there are abnormal movements or sensations) and partial complex seizures (during which the abnormal movement or sensation is accompanied by changes in consciousness ).

Prevention:
Generally, there is no known prevention for seizure disorders.

Symptoms:
Epilepsy is characterized by seizures of any type that occur on a chronic , recurrent basis and have no known cause. Nonspecific symptoms and/or signs may occur along with the seizures; including a headache , changes in mood or energy level, dizziness , fainting , confusion , and memory loss . An aura, sensations indicating a seizure is imminent, occur in some persons just prior to a generalized seizure.

Types of seizures and their symptoms:
PETIT MAL SEIZURES

  • minimal or no movements (usually, except for "eye blinking")
  • brief sudden loss of awareness or conscious activity
  • recurs many times
  • occurs most often during childhood
  • decreased learning

GRAND MAL SEIZURES (GENERALIZED TONIC-CLONIC SEIZURES)

SINGLE FOCAL SEIZURES

PARTIAL COMPLEX SEIZURES

  • automatism (automatic performance of complex behaviors)
  • abnormal sensations
  • may have nausea, sweating, skin flushing, and dilated pupils
  • may have other focal (localized) symptoms
  • recalled or inappropriate emotions
  • changes in personality or alertness
  • may or may not lose consciousness
  • olfactory (smell) or gustatory (taste) hallucinations or impairments -- if temporal focus



Signs and Tests:
The diagnosis of epilepsy and/or seizure disorders involves a history of recurrent seizures of any type. A physical examination , including a detailed neuromuscular examination, may be normal or may show focal neurologic deficits (localized abnormalities of brain functions).

  • An electroencephalograph ( EEG ), a reading of the electrical activity in the brain, usually confirms the presence of various types of seizures. It may, in some cases, indicate the location of the lesion causing the seizure .

Tests for the cause may include various blood tests (as appropriate depending on the suspected cause), including:

Tests for the cause may include procedures such as:

A physical examination and testing may be used to rule out other temporary and reversible causes of seizures such as a fever , various temporary chemical imbalances, toxemia of pregnancy , withdrawal from alcohol or drugs (especially benzodiazepines and barbiturates), use of drugs (especially street drugs), or other causes.

Disorders that may cause symptoms resembling seizures include transient ischemic attacks, rage or panic attacks, and any disorder that causes loss of consciousness or that causes tremors or tics as symptoms (abnormal muscle movements that are not caused by abnormal brain electrical activity).

Treatment:
If a seizure occurs, give appropriate emergency first aid.

EMERGENCY FIRST-AID TREATMENT, during generalized tonic-clonic seizure :

  • Protect the person from injury. Do not attempt to force a hard object (such as a spoon or tongue depressor) between the teeth, because you can cause more damage than what you are trying to prevent!
  • Clear the area of furniture or other objects that may cause injury from falls during the seizure. Do not attempt to restrain or hold the person down during the seizure.
  • Protect from aspiration (inhaling) of vomit or mucus. Turn the person onto the side if vomiting occurs. Keep the person on the side while he or she sleeps after the seizure is over.

If the person having seizures turns blue or stops breathing, turn him or her to the side to keep the airway open and prevent the tongue from obstructing the airway. Breathing usually starts on its own once the seizure is over. CPR or mouth-to-mouth breathing is rarely needed after seizures and cannot be performed during the seizure. Repeated or prolonged seizures (status epilepticus) may cause severe lack of oxygen in the body and are an emergency situation requiring immediate professional assistance.

EMERGENCY MEDICAL TREATMENT (status epilepticus):

  • Obtain professional medical assistance immediately.
  • Measures to protect the airway may be needed, including use of tubes to keep the airway open. Breathing should be supported as appropriate.
  • Intravenous glucose may be administered to the person on the chance that low blood sugar is responsible for the seizure.
  • Medications such as diazepam (Valium) or lorazepam, or anticonvulsant medications (such as phenytoin and phenobarbital) may be used to control prolonged, repeated, generalized seizures. They are usually injected into a vein. Other medical treatment may be indicated, including use of general anesthesia with neuromuscular blockade (" muscle paralyzers").
  • After status epilepticus is controlled, oral anticonvulsants are begun and tests are performed to determine the cause of the condition.

AFTER A SEIZURE
Record details of the seizure to report to the health care provider. Important details include date and time of the seizure, how long it lasted, which body parts were affected, the type of movements or other symptoms, possible causes, and other factors noted.

Isolated seizures are treated as specific for the type of seizure and the suspected cause (see the specific seizure type for details). Generally, this includes treatment of the cause and/or use of anticonvulsant medications.

Treat any injuries from bumps or falls.

AFTER DIAGNOSIS OF EPILEPSY (seizure disorder):
Treatment of causes, if a cause has been identified, may stop the occurrence of seizures. This may include medical treatment of disorders, surgical repair of tumors or brain lesions, or other treatments.

Oral anticonvulsants prevent or minimize the number of future seizures. Response is individual, and the medication used and dosage may have to be adjusted repeatedly.

Types of seizures and the corresponding medications:

  • Petit mal seizures usually respond best to valproic acid or ethosuximide. Clonazepam or other medications may also be used.
  • Grand mal seizures usually respond best to phenytoin, carbamazepine, valproic acid, or phenobarbital. Primidone or other medications may also be used.
  • Focal seizures or partial complex seizures usually respond to phenytoin or carbamazepine.

Follow-up for re-evaluation should occur at least yearly. Monitoring of plasma drug levels is important for the continued control of seizures and the reduction of side effects. Pregnancy ; lack of sleep; skipping doses of medications; use of drugs, medications or alcohol; or illness may cause seizures in a person with a previously well-controlled seizure disorder.

Use of informational jewelry or cards (such as Medic-Alert or similar) that indicate a seizure disorder may be advised to aid in obtaining prompt medical treatment if a seizure occurs.

Support Groups:
The stress of illness can often be helped by joining a support group where members share common experiences and problems. See epilepsy - support group .

Prognosis:
Seizure disorder (epilepsy) is a chronic , usually lifelong condition. In some cases, the need for medications may be reduced or eliminated over time. A seizure-free period of 4 years may indicate that reduction or elimination of medications is possible.

Death or permanent brain damage from seizures is rare but can occur if the seizure is prolonged or 2 or more seizures occur in proximity (status epilepticus). Death or brain damage are most often caused by prolonged lack of breathing and resultant death of brain tissue (infarction) from lack of oxygen (ischemia).

Serious injury can occur if a seizure occurs during driving or when operating dangerous equipment, so these activities may be restricted for people with poorly controlled seizure disorders.

Infrequent seizures may not severely restrict the person's lifestyle. Work, school, and recreation do not necessarily need to be restricted.

Complications:

  • prolonged seizures or closely occurring seizures (status epilepticus)
  • injury from such actions as falls, bumps, biting self
  • injury from having a seizure while driving and/or operating machinery
  • aspiration of fluid into the lungs and subsequent aspiration pneumonia
  • permanent brain damage ( stroke or other damage)
  • difficulty with learning
  • side effects of medications (with or without observable symptoms)



Call Your Healthcare Provider:
Go to the emergency room or call the local emergency number (such as 911) if this is the first time the person has had seizures or this is a new type of seizure for the person; the seizure lasts longer than 2 to 3 minutes; or repeated seizures occur (over any amount of time). Two or more seizures that occur over a few minutes or when consciousness is not regained between them (status epilepticus) is an emergency situation.

Call your health care provider if questions or concerns arise or if any new symptoms occur, including possible side effects of medications such as changes in mental status (such as drowsiness , restlessness , confusion , and sedation), nausea/vomiting , a rash , loss of hair , tremors or abnormal movements, and problems with coordination.