Childhood absence epilepsy (CAE) is a type of epilepsy that causes absence (“ab-SONCE”) seizures. Children will stare and stop what they are doing. They may blink quickly or move their hands. These seizures last only a few seconds. They may look like daydreaming or inattention.
Children with CAE may also have other types of seizures, particularly tonic-clonic seizures. When a person has a tonic-clonic seizure (sometimes called a “grand mal seizure”), they lose consciousness. Their muscles stiffen. They may fall to the floor. Convulsions begin, meaning the person’s arms and usually legs begin to jerk. The person may lose control of their bladder or bowels.
Childhood Absence Epilepsy Types
Absence epilepsy is sometimes called “petit mal epilepsy.” There are two types of absence epilepsies in children: CAE and juvenile absence epilepsy (JAE). CAE is much more common.
CAE and JAE are similar but not the same. The main differences are how often the seizures occur. CAE seizures occur at least once a day. JAE seizures are typically less than daily.
|Childhood Absence Epilepsy
||Juvenile Absence Epilepsy
- Seizures begin between 4 and 10 years of age.
- Seizures occur daily. They usually happen multiple times per day.
- Medication often helps to stop the seizures.
- About 10% of patients with childhood absence epilepsy also have tonic-clonic seizures.
- The child is likely to grow out of CAE by their mid-teens or early adulthood.
- Seizures begin between 12 and 17 years of age
- Seizures happen less than every day.
- As many as 80% of patients with juvenile absence epilepsy have tonic-clonic seizures.
- Seizures are more likely to continue into adulthood.
When absence seizures begin at age 10 or later, it can be hard to know whether they are caused by CAE or JAE. If the child has lots of seizures every day, the diagnosis will be CAE.
Childhood Absence Epilepsy Causes
Children with CAE are usually otherwise healthy, with no history of neurological, intelligence or developmental problems. Some children with CAE report a family history of similar seizures. But for most children, there is no genetic link or known cause for the condition.
When CAE occurs before the age of 4, the cause may be related to a rare genetic condition called “glucose transporter Type 1 (Glut1) deficiency.” This condition keeps sugar from crossing the child’s blood into the brain. Anti-seizure medications may not help children with this condition. Often being on a ketogenic diet can help.
Childhood Absence Epilepsy Symptoms
CAE seizures involve staring spells. The child is not aware or cannot respond during these spells. You may also see:
- The child’s eyes may roll up briefly.
- Each episode lasts seconds. The child goes back to normal right away.
- The child often is not even aware that anything has happened.
- Seizures can occur hundreds of times per day in some children.
A small number of children with JAE epilepsy will have one or more episodes of “absence status epilepticus.” This is when an absence seizure lasts for several hours or even a day or more. Absence status epilepticus is a medical emergency. The child needs “rescue medication” to stop the seizure.
Other Conditions Associated with Childhood Absence Epilepsy
Most children with CAE have normal intelligence and development. However, up to one-in-three can have attention issues like attention deficit hyperactivity disorder (ADHD). Attention issues can continue even when seizures are well treated. These children also have higher rates of anxiety or depression.
Childhood Absence Epilepsy Diagnosis
An accurate diagnosis is essential before treatment can begin. Your child’s doctor will ask for a detailed description of the seizures and do a physical exam. They may order tests, such as:
- Electroencephalography (EEG). An EEG measures electrical activity in the brain. Your child will blow on a pinwheel during the test because hyperventilation can trigger an absence seizure.
- Magnetic resonance imaging (MRI) or another kind of imaging test. This can help determine the cause of the seizures. It can rule out other problems, such as a brain tumor or stroke.
Childhood Absence Epilepsy Treatment
Medication often helps children with CAE get seizure control. Children with both absence and tonic-clonic seizures may need multiple medications to control seizures. The ketogenic diet may be an option for patients whose seizures continue even with medications.
Childhood Absence Epilepsy Prognosis
Most children grow out of CAE and can eventually stop their medication. They likely will have no problems with seizures later in life. Their seizures often disappear by mid-adolescence.