Published: May 3, 2007
Updated: May 3, 2007
Many parents are scared to death if their child has a seizure. It is usually a young child who has a fever and has had a short seizure.
Usually the parents have already taken the child to the emergency room, but when they come to me later they want answers: “Is it serious?” “Will my child have seizures all her life?”
Dr. Fawn Leigh, one of Duke’s pediatric neurologists, discusses childhood seizures and when to be concerned and when to be reassured.
-- Dennis Clements, MD, PhD, MPH
As a pediatric neurologist, I see many young patients with seizures. The first question usually asked is, “What is a seizure?”
A seizure is a sudden alteration of behavior or consciousness caused by abnormal electrical activity in the brain.
Seizures come in many forms. Some seizures involve convulsive activity such as jerking movements or stiffening of the body. Other seizures are exhibited by simply staring off into space.
The most common seizure typically begins with sudden change in the child’s level of alertness, followed by shaking or stiffening of the body lasting several minutes. Often, these seizures are followed by a period of decreased activity, usually sleepiness, and may include temporary paralysis.
This state can last anywhere from minutes to hours. While first-time seizures that last less than three to five minutes may be frightening, most are not serious and a visit with your child’s doctor may be all that is needed.
For prolonged, persistent seizure activity that lasts longer than five minutes, parents and caregivers should seek medical care. Seizures that are longer than 15 minutes and recurrent are termed “status epilepticus.” Status epilepticus is a medical emergency and must be managed by skilled physicians and not by parents.
Seizures are divided into two major categories (based on 1981 international classification):
Generalized seizures are divided into convulsive and nonconvulsive. Convulsive means that there is muscle movement such as stiffening (also known as tonic) or jerking (clonic) activity. When these movements are combined it may be called “grand mal.”
Other types of convulsive seizure activity include myoclonic and atonic seizure activity. Myoclonus is usually characterized by sudden, single jerks. Atonic seizure activity is typically characterized by dropping quickly to the floor as if suddenly asleep or paralyzed. The child then quickly recovers.
These two latter convulsive seizure types can both be difficult to diagnose and treat because often they are the manifestation of a mixed seizure disorder. In infants these seizures may be called infantile spasms.
Nonconvulsive means that there is alteration of consciousness without muscle movement. This form of seizure activity was formerly called “petit mal,” and is now commonly referred to as “absence.”
Absence seizures are unique in that typically they are characterized by an abrupt onset of staring and end just as abruptly with no confused state following the events. Parents usually report that the child looks like they are “spacing out.” (Teenagers who look like this often are not having seizures -- they are simply bored.)
Partial seizures can be simple or complex. Simple partial seizures are focal seizures that involve movement or sensation on one side of the body without altered consciousness. Simple partial seizures are commonly localized to areas in the brain called the motor or sensory strip.
Partial seizures may be with or without aura, which involves associated states such as fear, or changes in heart rate, flushing, or abdominal discomfort.
Complex partial seizures commonly originate from the frontal and temporal lobes of the brain where there are many complex interconnections, resulting in alteration of conscious. Typical complex partial seizures manifest as sudden change in level of alertness with or without aura, blank stare, confusional state, or aimless movements such as wandering around or repetitive behavior.
The above descriptions are broad characterizations of seizure types. In the real world, seizure presentations are not always as clear-cut. Commonly, there are overlapping signs and symptoms that make finding the seizure origin challenging.
For example, partial seizures starting on one side of the brain may spread to the whole brain and can look like a generalized seizure event with tonic-clonic activity of the entire body. This is why doctors often ask numerous questions about how the seizure began.
For parents and caregivers who are present during a seizure, the description of the beginning of the seizure event can be very helpful in diagnosing the seizure (and hence the treatment).
In addition to the history, an electroencephalogram (EEG) can provide functional assessment of the electrical activity in the brain and a brain MRI can provide structural assessment of the brain when they are indicated.
A common question that people ask when a child suddenly has a seizure is “Why did it happen?” In most children, doctors do not find a specific cause for the seizures. Children can have seizures from excessive fever or an underlying medical condition.
While it is frustrating not to be given a reason for the seizures, it is actually good news, because it means that your doctor has not found a serious cause of the seizure.
Common causes of seizures include:
Febrile seizures are the most common convulsive event in childhood. This is a unique kind of seizure, which occurs in early childhood in association with elevation in body temperature. These occur in about 2 to 5 percent of children between the ages of six months and five years when they have a high fever. This percentage means that approximately one in 25 children will have at least one febrile seizure.
The vast majority of febrile seizures are felt to be harmless and do not require daily anticonvulsant therapy. A daily anticonvulsant should only be considered for children with complex febrile seizures, meaning febrile seizures that are focal, prolonged, or recur within 24 hours.
Although children who have had febrile seizures are at increased risk for developing epilepsy, the risk is still in most cases very small. However, children with a pre-existing neurological condition or developmental delay have a greater risk of developing recurrent seizures.
After an initial febrile seizure in children younger than 12 months, a lumbar puncture is frequently considered to rule out meningitis, as other signs and symptoms of this serious condition may be minimal or absent in this age group.
In children 12 to 24 months, a lumbar puncture may also be considered. In children older than 24 months, the decision to perform a lumbar puncture depends on the child’s clinical presentation.
There is no specific test for the diagnosis of seizure. The diagnosis is made by putting together a constellation of information. Tests such as an EEG can be helpful in determining the type of seizure and can assist the doctor in selecting a medication. The findings on an EEG, taken together with the description of the seizure event, recurrence and family history, all contribute to the diagnostic process.
For each seizure type, there are several anticonvulsants that may be equally effective. The selection of medication is usually based on many factors including the seizure type, side effects, your child’s medical history, interactions with other medications that your child is taking, previous drug allergies, your child’s age, convenience, and cost.
Successful management of seizure disorder in children requires a team approach. This team typically includes parents, caregivers, teachers, skilled therapists, and the physician.
Most importantly, the well-being of the child should be the center focus. Communication among these team members is invaluable in coordinating a comprehensive treatment plan, which includes medication, education, supportive interventions, and observation.
While medication controls a majority of seizure disorders, there remains the group of children with intractable epilepsy, such as uncontrollable seizures, that can be devastating and associated with developmental disabilities.
The epilepsy research community continues to concentrate its efforts on identifying causes of epilepsy, new technology for diagnosis, drug development, and surgical techniques with hope for better treatment options and potential cures.
-- Fawn Leigh, MD, is a pediatric neurologist at Duke Children’s Health Center. Dr. Leigh evaluates and treats a wide spectrum of neurological disorders in children, including seizures, movement, neuromuscular, and neurocutaneous disorders. Dr. Leigh has a research interest in Neurofibromatosis (NF) and has established a collaborative initiative with the Neuroproteomics Laboratory to identify potential biomarkers in NF.
-- Dennis Clements, MD, PhD, MPH, is the chief of primary care pediatrics at Duke Children's Hospital.