Epilepsy in Children
To understand epilepsy, you first have to understand how the brain functions. The brain controls and regulates all voluntary and involuntary responses in the body. It consists of nerve cells that normally communicate with each other through electrical activity.
Epilepsy is defined as two or more seizures that occur without a specific cause. Seizures are altered behavior that occurs when part(s) of the brain receives a burst of abnormal electrical signals that temporarily interrupts normal electrical brain function.
Different kinds of epilepsy are classified according to:
- Signs and symptoms
- The child's age when they begin to occur
- The child’s EEG pattern
- Neurologic findings on examination
- Special kinds of imaging (x-ray-type) tests, including magnetic resonance imaging (MRI) and computerized tomography (CT) scans
Approximately 4-6% of children have a single seizure during childhood, and approximately 1% has two or more. Of those who have two or more seizures, 70-80% eventually outgrow the condition.
These seizures take place when abnormal electrical brain function occurs in one or more areas of one side of the brain. If the child does not lose consciousness throughout the seizure, the seizure was previously classified as simple. If the child loses consciousness or does not respond appropriately, the seizure was previously classified as complex.
Focal seizures may include one-sided jerking movements of the arms or legs, stiffening, eye deviation to one side or twisting of the body. Sometimes these symptoms follow these other signs:
- Seeing visions
- Hearing noises
- Tasting and smelling things
- A rapid heart rate
- Dilated pupils
- Stomach fullness
- Psychic symptoms such as a sense of deja-vu, distortions, illusions and hallucinations
These seizures involve both sides of the brain. As a result, the seizures are less variable than focal seizures.
Typically, they involve brief staring spells; sudden, quick muscle jerks; generalized and rhythmic jerking of the extremities; generalized stiffening episodes; or generalized stiffness followed by rhythmic jerking of the extremities or a sudden loss of muscle tone, resulting in a head drop or sudden fall to the ground.
Fever (febrile seizures) are caused by fever in children age three months to five years of age, with no other underlying neurologic problems present. Febrile seizures are common and occur in 2-5% of all children. Simple febrile seizures are brief (usually less than five minutes), generalized convulsions that only occur once in the course of an illness.
Metabolic or chemical imbalances in the body may also cause seizures. Conditions that prompt seizures include hypoglycemia (low blood sugar), hypo/hypernatremia (too little or too much sodium in the blood) and hypocalcemia (too little calcium). Meningitis or encephalitis (brain infections) may also induce seizures. Other acute problems that can cause seizures include toxins, trauma and strokes. In children with epilepsy, a common reason for sudden increase in seizures is that the youngsters are not taking their medications as directed.
Trauma at birth or brain abnormalities such as tumors can also be the source of seizures. A lack of adequate oxygen near the time of birth, trauma, infection and stroke can induce a seizure. Sometimes the seizures appear suddenly, although the brain abnormality may have been present for a long time.
Seizures can also develop as a result of a neurodegenerative disease. While neurodegenerative diseases are rare, they can be devastating.
The best tool the doctor has to evaluate the spells is the child's history. This includes knowing what happened immediately before the seizure, the first indication that something was wrong, a complete description of the event, the level of responsiveness of the child, how long the seizure lasted, how it resolved and what the child did after the event. All or some of the following tests may be used:
- Blood tests
- Electroencephalogram (EEG) – A procedure that records the brain's continuous, electrical activity by means of electrodes attached to the scalp.
- MRI – A diagnostic procedure that uses a combination of large magnets, radiofrequencies and a computer to produce detailed images of organs and structures within the body.
- CT scan – A diagnostic imaging procedure that uses a combination of x-rays and computer technology to produce cross-sectional images (often called slices) of the body, both horizontally and vertically. A CT scan shows detailed images of any part of the body, including the bones, muscles, fat and organs. CT scans are more detailed than general x-rays.
- Lumbar puncture (spinal tap) – A special needle is placed into the lower back into the spinal canal. This is the area around (but not into) the spinal cord. The pressure in the spinal canal and brain can then be measured. A small amount of cerebral spinal fluid (CSF) can be removed and sent for testing to determine if there is an infection or other problem. CSF is the fluid that bathes your child's brain and spinal cord.
Many types of medications may be used to treat seizures and epilepsy. Epilepsy medications are selected based on:
- The seizure type
- Child’s age
- Side effects
- Medication cost
- Consistent use of the medication
Medications used at home are usually taken by mouth (as capsules, tablets, sprinkles or syrup), but some can be given rectally (into the child's rectum as a suppository). If your child has seizures while in the hospital, they may be given injections or intravenous (IV).
It’s important to give your child their medication on time and as prescribed by your child's physician. Each person’s body works differently, so adjustments in schedule and dosage may be needed for good control of seizures. All medications may have side effects, although some children may not experience any. Discuss your child's medication side effects with their physician. While your child is taking medications, different tests may be done to monitor the effectiveness of the medication. These tests may include the following:
- Blood work: Frequent blood draws testing may be required to check the level of the medication in the body. Based on this level, the physician may increase or decrease the dose of the medication to achieve the desired level. This level is called the "therapeutic level," and is where the medication works most efficiently. Blood work may also be done to monitor the effects of medications on body organs.
- Urine tests: These tests are performed to see how the child's body is responding to the medication.
You should weigh the risks and benefits of therapy versus the risks of a subsequent seizure before your child begins taking a medicine. Treatment is generally not started after the first seizure in children.
While reports vary, the recurrence risk after the first seizure, if it occurred for no apparent reason, is approximately 40%. The majority of recurrent seizures occur soon after the first event — 50% occur within six months.
The use of only one drug is preferable if possible, as approximately 70% of children become seizure-free on therapy with one medication. Another 15% of children become seizure-free on a combination of several. The final 15% have epilepsy that does not respond to medication.
- Ketogenic diet – A strict, high-fat diet useful for generalized seizures that don't respond to medication.
- Vagal nerve stimulator – A surgically implanted wire around the vagal nerve hooked to a pacemaker device in the chest that is programmed to give intermittent stimulation to the vagal nerve. This device is FDA-approved as adjunctive therapy for partial seizures in children over age 12. However, some researchers believe it’s useful for younger children, as well as in children with intractable generalized seizures.
- Epilepsy surgery – For some patients, particularly those with focal seizures that don't respond to medication or with identifiable lesions on head imaging studies, epilepsy surgery may be the best treatment.
Status epilepticus (SE) is any type of seizure lasting more than 30 minutes. It occurs in about out 100,000 to 150,000 cases per year and children represent about half of these cases. About 75% of children with epilepsy that begins before age one have at least one episode of SE, and it represents approximately 5% of all febrile seizures.
SE may occur in all the types of seizures seen in children of different ages. It may be triggered by the following:
- A change in or abrupt termination of medications
- Poison ingestion
- Metabolic derangements and disease
Early appropriate treatment is best. Since most seizures last less than one to two minutes, we recommend that acute treatment be initiated for seizures lasting longer than five minutes.
There are many behaviors that, while they may be alarming, aren’t signs of a seizure. They include:
- Apnea (not breathing for more than 15 seconds), though rarely the only evidence of a seizure
- Infants with gastroesophageal reflux disease (GERD), a digestive disorder in which gastric acid flows from the stomach into the esophagus; may have spells of staring, stiffening and arching of the back
- Some sleep disorders, including night terrors, sleepwalking and other conditions
- Certain kinds of migraine headaches
- Breath-holding spells in children six months to six years old.
- Movement disorders, such as jitteriness, shuddering attacks, tics, Tourette's syndrome and others
- Inattention or daydreaming spells
- Repetitious behaviors such as head banging, body rocking, temper tantrums and "rage attacks"
- Pseudoseizures/psychogenic seizures in response to emotional stress