Infantile Spasms

What are infantile spasms?

Infantile spasms, sometimes called West syndrome, are a type of seizure that occurs in babies. The spasms look like a sudden stiffening of muscles, and the baby’s arms, legs, or head may bend forward. The seizures occur in a series of short spasms, about one to two seconds in length. Babies may have as many as 100 spasms a day. The seizures may be more likely to happen just as the baby is waking up.

Infantile spasms most often begin between 4 and 7 months, but can start any time in the first few years of life. Later onset spasms may also occur but are rare. Infantile spasms require specific medication to stop the spasms. Children with Infantile spasms are at risk for development of difficult-to-control epilepsy, intellectual disability, and autism. Early and effective treatment is important in improving the prognosis for these infants, as early responders have better long-term epilepsy and developmental outcomes.

How we care for infantile spasms

The Infantile Spasms Program is dedicated to providing timely evaluation, testing, treatment, and follow-up for infants with new onset infantile spasms, refractory infantile spasms, and later-onset epileptic spasms. We offer a full range of epilepsy care, including medication-based  and dietary treatment for spasms, as well as timely evaluation for epilepsy surgery in infants who have difficult-to-control spasms.

We are a Level 4 Epilepsy Center, recognized by the National Association of Epilepsy Centers, and one of the few Level 4 Epilepsy Centers in the country dedicated to caring for children. Our center performs epilepsy surgery in eligible children, including infants.

What are the symptoms of infantile spasms?

Infantile spasms often look like a sudden, brief stiffening of a baby’s muscles. Symptoms may include:

  • a cluster of spasms that may be associated with waking from sleep
  • jackknife seizures, where the body bends forward, the knees are pulled up, and the arms are thrown out to the side
  • a stiffening of the body and legs, with the head thrown back
  • decreased visual alertness

In some cases, the symptoms are subtle, such as a mild head nod or quick eye movements.

What causes infantile spasms?

Infantile spasms may be associated with specific disorders, such as tuberous sclerosis, certain genetic abnormalities, or brain injury or infection. In some cases there is no known cause. 

How are infantile spasms diagnosed?

To diagnose infantile spasms, your child’s doctor will complete a physical and neurologic exam. Your baby will also need a test called an electroencephalogram (EEG), which looks at electrical activity in the brain.

Babies who have infantile spasms often have a unique EEG pattern called hypsarrhythmia. This is a pattern of disorganized background activity and  high-voltage spikes and slow waves. Other EEG patterns are also associated with infantile spasms. Your baby's doctor may want to look at EEG patterns when your child is awake, asleep, as well as capturing spams.

How are infantile spasms treated?

Early diagnosis and treatment of infantile spasms may help to lessen developmental issues. Treatments may include:

  • adrenocorticotropic hormone (ACTH) or high dose prednisolone
  • vigabatrin (a specific anti-seizure medication)
  • ketogenic diet
  • anti-seizure medications

If your child has difficult-to-control spasms, treatment with epilepsy surgery may be an option. When evaluating for epilepsy surgery your doctor may want to get a PET (positron emission tomographyscan in addition to an MRI and EEG. Depending upon the findings from these tests, your child’s doctor may recommend epilepsy surgery, such as lobar resection or hemispherectomy, or a palliative procedure such as corpus callosotomy. Your child’s doctor will review the treatment options that may work best for your child.

What is the long-term outlook for infantile spasms?

Children with infantile spasms are at risk for developing other types of seizures as they age. They also may be at risk for autism and cognitive delays. Early diagnosis and treatment may help reduce this risk.