What Is Infantile Spasm?

Infantile spasms (also called West syndrome because it was first described by Dr. William James West, in the 1840s) consist of a sudden jerk followed by stiffening. Often the arms are flung out as the knees are pulled up and the body bends forward ("jackknife seizures"). Less often, the head can be thrown back as the body and legs stiffen in a straight-out position, or movements can be more subtle and limited to the neck or other body parts. Each seizure lasts only a second or two but they usually occur close together in a series. Sometimes the spasms are mistaken for colic, but the cramps of colic do not occur in a series.
Infantile spasms are most common just after waking up and rarely occur during sleep.

Who gets it?

Infantile spasms begin between 3 and 12 months of age, but could happen up to the age of 4 and usually stop by the age of 2 to 6 years or change to other types of seizures. It is likely that this age dependence is due to the stage of development of the brain. 60% of babies with Infantile Spasm are usually causes by a disease or disorder that affects the brain. Perhaps there was a problem before the child was born. If this problem occurred at a very early stage then the brain may not have been built correctly. This problem might be obvious and the parents might already know that it exists or it may need investigations to find it. Perhaps there was a problem around the time of birth and the brain was developing normally but was damaged. Damage to a normal brain can occur to babies during pregnancy, from child birth, and it can also occur in babies born prematurely – usually before 32 weeks of pregnancy where the brain is not yet strong enough to withstand being born. Damage can also occur after birth from meningitis or trauma for example, but others have had no apparent injury and have been deveoping normal. If you read about infantile spasms, you will come across words about the causes of infantile spasms. Often, doctors talk about idiopathic, cryptogenic and symptomatic causes.

But even after investigations are complete, we still do not know why the condition has started in about one third of infants. They are uncommon, affecting only one baby out of a few thousand babies and there is no evidence that family history, the baby's sex, or factors such as immunizations are related to infantile spasms.

How is the diagnose made?

When a baby with infantile spasms has an EEG, the doctor usually will see an unusual pattern called hypsarrhythmia (HIP-sa-RITH-me-ah) when the seizures are not occurring. This chaotic, high-voltage pattern is often helpful in confirming the diagnosis.
Babies with infantile spasms seem to stop developing and may lose skills that they had already mastered, such as sitting, rolling over, or babbling.

How is it treated?

Steroid therapy (adrenocorticotropic hormone [ACTH] or prednisone) is the primary treatment for infantile spasms. Some experts recommend trying a seizure medicine such as Sabril (vigabatrin, not available in the United States), Depakote (valproate), or Topamax (topiramate) before steroid therapy. In countries where it is available, Sabril is often used as the initial therapy because it is relatively safe (especially for short-term use) and effective. It is especially effective for children with tuberous sclerosis (a disorder associated with abnormalities involving the brain, skin, heart, and other parts of the body). Sabril is associated with damage to the retina of the eye and should be used with caution in children.
What's the outlook?
Most children with infantile spasms are mentally retarded later in life. Those whose spasms are related to an underlying developmental brain disorder or injury have a higher likelihood of moderate to severe retardation. The outlook is brighter for those who were developing normally before the spasms started: 10 to 20% will have normal mental function and some others may be only mildly impaired. Some children with infantile spasms develop autism. Many doctors believe that the quicker the seizures are controlled, the better the results will be.
When the spasms stop, many children later develop other kinds of epilepsy. About one-fifth of children who have had infantile spasms will have the Lennox-Gastaut syndrome.