Infantile Spasms (West Syndrome)

What Are Infantile Spasm (West Syndrome)?

Infantile spasms is a rare type of seizure disorder that occurs in infants between the ages of 4 and 6 months. 

Symptoms of Infantile Spasms

The seizures usually occur when the infant awakening or trying to fall asleep. The infant typically has brief periods of spasms of the neck, trunk or legs that last for a few seconds. Infants may have clusters of seizures with up to hundreds per a day, which can be a serious problem and cause long-term complications. Infants typically have normal development prior to onset of seizures.

Infantile Spasms Diagnosis

About three-fourths of infants with infantile spasms have underlying brain abnormalities. The physician will order a variety of tests, such as EEG, CT, and/or MRI brain imaging. The EEG will show hypsarrhythmia, which is a chaotic pattern between seizures. CT or MRI neuroimaging will test for signs of tuberous sclerosis, a brain infection or structural abnormality.

Normal EEG Awake compared to Infantile Spasms

Treatment for Infantile Spasms

In some infants, spasms will stop spontaneously without any treatment. But most will require anti-epileptic drugs such as Sabril® (vigabatrin), adrenocorticotropic hormone, or ACTH® (corticotrophin), or prednisone, to control the seizures. Infantile spasms caused by tuberous sclerosis respond well to Sabril®.

ketogenic diet may also control or reduce seizures in some infants. 

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