Infantile Spasms

What are infantile spasms?

Infantile spasms are a neurological seizure disorder, also known as West syndrome, that occurs in babies. It typically begins between 4 and 8 months of age. This is a very serious form of epilepsy and can have long-term consequences. Early treatment is critical.

When do infantile spasms happen and what do they look like?

Infantile spasms often occur when a child is falling asleep or waking up. The child’s body may suddenly jerk, flex or extend. Sometimes, the arms are flung out, the knees are pulled up and the body bends forward. Less often, the head can be thrown back while the body and legs stiffen to a straight position. Each spasm lasts a few seconds, but multiple may occur close together in a cluster. They should not be confused with colic cramps, which don’t occur in a series. Infantile spasms take many forms and can be subtle.

What are symptoms of infantile spasms?

The most recognizable symptom of infantile spasms is the sudden and brief stiffening of a baby’s muscles. However, in some cases, symptoms are more subtle and look closer to a head nod or quick eye motion. Other typical symptoms of infantile spasms include:

  • Clustered of short spasms that occur in a pattern.
  • Spasms that wake babies from sleep.
  • Jackknife seizures. This is when a baby’s body bends forward with their knees pulled up and arms thrown out their sides.
  • Body and leg stiffening with their head thrown back.
  • Decline in visual alertness.

Babies who have infantile spasms may also experience noticeable changes in development as a symptom. They can start to experience delays or regress in their development. Delays in development may be seen through a noticeable slowdown in their progression of reaching milestones. While developmental regression can be seen through a loss of skills that were already learned/achieved.

What causes infantile spasms?

Infantile spams can be caused by almost any condition that affects the brain. In less common cases, they can also be associated with some metabolic and genetic disorders, and even more rarely are a result of vitamin B6 deficiency. However, the most common causes of infantile spasms include:

  • Improper brain development in the womb
  • Infections affecting the brain
  • Traumatic brain injuries
  • Abnormal blood vessels in the brain

Some children with infantile spasms have no pre-existing brain condition and developed normally prior to the onset of infantile spasms. In these cases, the cause can remain unknown.

How are Infantile Spasms Diagnosed?

Infantile spasms are diagnosed through physical and neurological tests conducted by a pediatric neurologist. Testing looks for both evidence of infantile spasm occurrence as well as underlying conditions that are known to cause infantile spasms. Tests can include:

  • Blood & Urine tests that check for infections.
  • EEG that looks at electrical brain activity.
  • CAT/CT Scan or MRI to look inside the brain.

A unique EEG pattern called hypsarrhythmia is often associated with infantile spasms and can help determine a diagnosis. Hypsarrhythmia is a pattern of disorganized background activity, high-voltage spikes and slow waves. EEGs may be conducted when your child is awake, asleep and during a spasm to help verify diagnosis.

How are infantile spasms treated?

Adrenocorticotropic hormone (ACTH) therapy is the mainstay treatment for infantile spasms. ACTH is a hormone that is produced in the pituitary gland located at the base of the brain. An injection can stimulate the production of cortisol in the brain that helps to relieve infantile spasms. Infants with a dual diagnosis of infantile spasms and tuberous sclerosis may sometimes be placed on another epilepsy medication known as Vigabatrin (also known as Sabril).

What is the long-term outlook for a child with infantile spasms?

In many cases, the earlier the seizures are recognized and treated, the better the outcome will be for the child. Long-term effects of infantile spasms can include epilepsy, further developmental delay, cognitive impairments and autism.

Related Stories

CHOC patient Isa poses with 11th birthday decorations

11-year-old Isa had to relearn everything after treatment for FIRES, a rare epilepsy disorder. With help from CHOC rehab, he’s thriving.

CHOC logo  CHOC Health

Parent feels sick baby's head - what parents should know about febrile seizures

A CHOC neurologist assures parents that most children recover from febrile seizures and offers treatment tips and advice.

CHOC logo  CHOC Health

Bryce standing in front of his brain scans

Responsive neurostimulation (RNS), a new therapy for epilepsy, helped 11-year-old CHOC patient Bryce become nearly seizure-free.

CHOC logo  CHOC Health