Epilepsy

Epilepsy is a condition in which a person experiences symptoms such as recurrent seizures.

Epilepsy is a condition in which a person has recurrent seizures.

A seizure is defined as an abnormal, disorderly discharging of the brain's nerve cells, resulting in a temporary disturbance of motor, sensory, or mental function.

There are many types of seizures, depending primarily on what part of the brain is involved. The term epilepsy says nothing about the type of seizure or cause of the seizure, only that the seizures happen again and again. A stricter definition of the term requires that the seizures have no known underlying cause. This may also be called primary or idiopathic epilepsy.

• Episodes of abnormal electrical activity within the brain result in seizures.
• The specific area of the brain affected by abnormal electrical activity may result in a particular type of seizure.
• If all areas of the brain are affected by abnormal electrical activity, a generalized seizure may result. This means that consciousness is lost or impaired. Often all the person's arms and legs stiffen and then jerk rhythmically.
• One seizure type may evolve into another during the course of the seizure. For example, a seizure may start as a partial, or focal, seizure, involving the face or arm. Then the muscular activity spreads to other areas of the body. In this way, the seizure becomes generalized.
• Seizures caused by high fevers in children are not considered epilepsy.

Healthy people may have seizures under certain circumstances. If the seizures have a known cause, the condition is referred to as secondary or symptomatic epilepsy. Some of the more common causes include the following:

• Tumor
• Chemical imbalances such as low blood sugar or sodium
• Head injuries
• Certain toxic chemicals or drugs of abuse
• Alcohol withdrawal
• Stroke, including hemorrhage
• Birth injuries

Almost any type of behavior that happens repetitively may represent a seizure.

• Generalized seizures: All areas of the brain (the cortex) are involved in a generalized seizure. Sometimes these are referred to as grand mal seizures.
  • To the observer, the person experiencing such a seizure may cry out or make some sound, stiffen for some seconds, then have rhythmic movements of the arms and legs. Often the rhythmic movements slow before stopping.
  • Eyes are generally open.
  • The person may not appear to be breathing. The person is often breathing deeply after an episode.
  • The return to consciousness is gradual and should occur within a few moments.
  • Loss of urine is common.
  • Often people will be confused briefly after a generalized seizure.
• Partial or focal seizures: Only part of the brain is involved, so only part of the body is affected. Depending on the part of the brain having abnormal electrical activity, symptoms may vary.
  • If the part of the brain controlling movement of the hand is involved, for example, then perhaps only the hand may show rhythmic movements or jerking.
  • If other areas of the brain are involved, symptoms might include strange sensations or small repetitive movements such as picking at clothes or lip-smacking.
  • Sometimes the person with a partial seizure appears dazed or confused. This may represent a partial complex seizure. The term "complex" is used by doctors to describe a person who is between being fully alert and unconscious.
• Absence or petit mal seizures: These are most common in childhood.
  • Impairment of consciousness is present with the person often staring blankly.
  • Repetitive blinking or other small movements may be present.
  • Typically, these seizures are brief, lasting only seconds. Some people may have many of these in a day.
  • Other seizure types exist particularly in very small children.

Dravet Syndrome is a rare seizure disorder caused by a genetic abnormality that starts in infancy. It’s a lifelong epileptic condition that causes developmental and cognitive problems in people who suffer from it, according to the U.S. National Institute of Neurological Disorders and Stroke.

What are the symptoms of Dravet syndrome?

Symptoms of Dravet syndrome may range from mild to severe and include:

• Convulsive seizures that begin before 15 months of age
  • Seizures are prolonged and involve half of the body
  • Subsequent seizures may involve the opposite half of the body
  • Temperature changes, like exiting a warm bath, can bring on a seizure
  • Status epilepticus, a medical emergency condition of continuous seizure, may happen often in children with Dravet, especially before age five.
• Developmental cognitive and physical delays resulting from seizures
• Changes in eating and appetite
• Crouched gait and compromised balance as the child grows older

Most cases of Dravet (about 80%, according to the NIH) are caused by a harmful mutation of the SCN1A gene. This gene encodes for sodium channels in neuron membranes, the proper functioning of which is crucial for movement and sensory tasks and baseline homeostasis (balance) within the nervous system.

What is the treatment for Dravet syndrome?

Treatment for Dravet syndrome, until 2018, mostly relied on general seizure medications targeting the faulty neuronal sodium channels, the NIH states. This was when the U.S. Food and Drug Administration approved cannabis-based Epidiolex (cannabidiol) as the first medication for Dravet, specifically, and the first cannabidiol-based medication approved in the U.S.

Fenfluramine, first released as an appetite suppressant, is also an FDA-approved medication approved for Dravet syndrome in patients age 2 and older as of June 2020, according to the NIH.

Other seizure medications (oxcarbazepine, carbamazepine, phenytoin, and lamotrigine) shouldn’t be used on a daily basis – especially in small children – as they can increase the number of seizures and make them worse in the long term, the NIH states.

What is the prognosis for Dravet syndrome?

Cognitive disability can range from mild to profound. Most people with Dravet, also known as severe myoclonic epilepsy of infancy (SMEI), are reliant on caretakers throughout their lives, though the severity of symptoms may vary, the NIH states.

People with Dravet have fewer seizures as they grow older, and more than a 300% increased chance of early death, according to one study. About 16 people per 1000 with Dravet will die in a given year as opposed to 5 in 1000 with no serious underlying health conditions, according to the 2016 study published in Epilepsy Research. The numbers were based on the outcomes from 100 people with Dravet followed for about 17 years.

An estimated 10% to 20% of individuals with Dravet syndrome die before they reach adulthood.

A first seizure is a reason to visit your doctor or a hospital's emergency department. For someone with a diagnosed seizure disorder, a change in seizure patterns or more frequent seizures are reasons to see the doctor.

Visits to a hospital's emergency department are not needed for everyone with a seizure. Some seizures are emergencies, as in the following cases when 911 should be called:

• A seizure that continues for more than 5 minutes 
• Breathing difficulty 
• Persistent confusion or unconsciousness 
• Injuries sustained during a seizure
• A first seizure

The first task facing the doctor is to decide if the event was a seizure or some other condition, such as fainting, that may mimic a seizure.

• The doctor will take a history of the facts that surrounded the event. Any eyewitness accounts will be very helpful. Family history, social history, and past medical history are important as well.
• Bring any medicine containers, including prescription drugs, to the hospital to help the doctor make the diagnosis.
• A neurological examination will be performed. This may include some tests not usually performed in other physical examinations, such as strength and reflex testing.
• Depending on the history and physical examination, laboratory work may be ordered. This might include blood or urine testing.
• Special testing such as MRI, CT scans, or EEG (brain wave patterns) may be performed.

Home care with epilepsy varies with the frequency and type of seizures. It is important to take anticonvulsant medication regularly to prevent seizures.

When a seizure occurs, an observer can use common sense to prevent injuries.

• Cushion the person's head.
• Loosen any tight neckwear.
• Turn the person on his or her side.
• Do not hold the person down or restrain the person.
• Do not place anything in the mouth or try to pry the teeth apart. The person is not in danger of swallowing his or her tongue.
• Observe seizure characteristics-length, type of movements, and direction of head or eye turning. These characteristics may help the doctor diagnose the type of seizure.

Depending on the seizure type, different treatments may be prescribed. This will often include anticonvulsant medication that prevents or stops seizures.

• The type of anticonvulsant medication selected by your doctor will depend on factors such as seizure type, cost, and other medical conditions.
• Anticonvulsant medications may need frequent adjustments, especially after starting medications.
• Monitoring of anticonvulsant medications and other laboratory tests may be necessary.

Follow-up varies tremendously depending on an identified cause of seizures and the frequency of seizures.

• For people with infrequent seizures who are on constant medications, follow-up visits once or twice a year may be adequate.
• If the seizures are difficult to control or if new medications are being used, weekly visits are not unusual.

If the seizures are related to another medical condition, identification and treatment of that medical condition is the key to prevention. If anticonvulsant medication is prescribed, taking the medication on the recommended schedule and not missing medication is important.

• Some people with epilepsy are quite sensitive to alcohol. If this pattern develops, avoid alcohol. Others may have seizures only after ceasing heavy alcohol intake. The key to prevention is avoidance of alcohol.
• Sleep deprivation and stress certainly may increase the frequency of seizures in some people with epilepsy.

Epilepsy simply describes the condition of recurrent seizures. The outcome of the seizure disorder is strongly related to the cause of the seizures if a cause is discovered.

For people with symptomatic epilepsy—that is, seizures that occur because other medical conditions exist—prognosis will depend on the other medical condition.

• Seizures resulting from low blood sugar, for example, could be prevented by careful management and avoidance of hypoglycemia (low blood sugar).
• Seizures related to progressive medical conditions such as some brain tumors or metabolic conditions may be difficult to control and may have a poor outcome.

Epilepsy.com

Epilepsy Association of Calgary

Hawaii Epilepsy Center

British Epilepsy Association

National Institute of Neurological Disorders and Stroke, Epilepsy Information Page

MedlinePlus, Epilepsy