Frequently asked questions about infantile spasms

1. What is infantile spasms?

Infantile spasms, also called "epileptic spasms" or West Syndrome, is a type of epilepsy that tends to affect infants under the age of 2 years, and is characterized by clusters of peculiar seizures. These seizures—termed  spasms—are involuntary and usually consist of a brief interruption of behavior, often with lifting and extension of the arms and bending forward at the waist. In many cases, this behavior is accompanied by a rapid and forceful drop of the head. Each cluster typically lasts a few minutes. There are many variations of this pattern.  After individual spasms, children often cry. Clusters of spasms most often occur upon awakening, but can happen at any time of the day. A typical example is presented in the video below. For additional examples of infantile spasms, please see our collection of videos.

2. What is epilepsy?

Epilepsy simply indicates a tendency for seizures. There is an enormous spectrum of epilepsy, from very mild to very severe. Some people with epilepsy will only have a few seizures in their lifetime and others may have hundreds or even thousands of seizures in a single day.

3. What causes infantile spasms?

There are countless causes for infantile spasms. Almost any brain abnormality or injury to the brain has the potential to cause infantile spasms.  In addition, despite thorough medical evaluation, approximately 10% of children with infantile spasms have no identified cause. It is unclear why some infants with risk factors for infantile spasms ultimately develop it, and others do not.

4.  How common is infantile spasms?

In comparison to epilepsy, which is very common, infantile spasms are fairly rare. There are approximately 2000 to 4000 new cases in the United States each year.

5. What is the outcome of infantile spasms? How can it affect children?

The outcome of infantile spasms is highly varied, but infantile spasms are notorious for causing poor cognitive development, such as mental retardation. The underlying cause of infantile spasms, if identified, is the key factor that can help predict developmental success or failure. Of equal importance, it is essential that infantile spasms are promptly and successfully treated. As such, when infantile spasms are suspected, the diagnosis should be rapidly confirmed, a search for the cause of infantile spasms should begin, and treatment should be started immediately. Normal development is possible in those cases in which an underlying cause of infantile spasms is mild or unknown (often called "cryptogenic"), and treatment is prompt and successful.

6. How is infantile spasms diagnosed?

Children with suspected infantile spasms should be promptly evaluated by a pediatric neurologist or pediatric epileptologist. The cornerstone in the diagnosis of infantile spasms is a test called video-electroencephalography, or "video-EEG" for short. This test consists of simultaneous video and electroencephalography (EEG). EEG testing allows visualization of brain waves and is accomplished by the temporary attachment of electrodes to the scalp with a variety of adhesives. To confirm the diagnosis of infantile spasms, video-EEG is needed to verify specific brain-wave patterns during the spasms and document specific patterns in between the spasms. Neurologists will specifically look for a pattern called hypsarrhythmia, which is characterized by chaotic, high-amplitude brain waves.

7. Which medications are used to treat infantile spasms?

There are a variety of treatments available. There is broad consensus that the most effective drug therapies include several hormonal therapies and a drug called vigabatrin. The hormonal therapies include very high-dose corticosteroids (e.g. prednisolone, prednisone, and others) as well as high-dose adrenocorticotropic hormone (also known as ACTH or corticotropin, and marketed in the United States under the brand name Acthar®). The precise mechanism by which hormonal therapies act on infantile spasms is unknown. Vigabatrin (Sabril®) is a medication used to treat infantile spasms as well as complex partial seizures in adults. Vigabatrin acts by increasing the amount of GABA (an inhibitory brain signaling molecule) in the brain. Less effective therapies include zonisamide (Zonegran®), topiramate (Topamax®), clonazepam (Klonopin®), clobazam (Onfi®), and valproic acid (Depakote®/Depakene®).

8. Are there any treatments in addition to medications?

Among children who do not respond to medications, surgery to remove seizure-generating parts of the brain, as well as the ketogenic diet (a specialized very-high fat diet useful in treating many types of epilepsy) may be helpful in select patients. Of course, decisions regarding therapy should be guided by your pediatric neurologist.


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