Understanding Infantile Spasms (West Syndrome): Symptoms, Causes, and More

Infantile spasms, also known as West syndrome, is a rare type of seizure disorder that affects babies. If your baby has been diagnosed with infantile spasms, it's important to understand the symptoms, causes, and how doctors diagnose this condition.

Symptoms of Infantile Spasms

The main symptoms of infantile spasms are seizures and spasms that last only a few seconds and happen in clusters. These seizures can be mild or forceful, and your baby may have more than one type. Some common types of seizures in infantile spasms include:

• Nodding head seizures

• Stiffening of the body with arms and legs flinging out

• Arms and legs going straight out with head thrown back

• Seizures affecting only one side of the body

Your baby may also cry right before or after a seizure, and they may seem to twitch or jerk a muscle, which is called myoclonus. There are two types of myoclonus:

• Positive myoclonus: Muscles suddenly tense up, causing a twitch

• Negative myoclonus: Muscles suddenly relax, causing a twitch

Infantile spasms can also affect your baby's autonomic nervous system, which controls things like heartbeat and pupil size. During a seizure, your baby may:

• Turn pale or red

• Sweat

• Have big pupils

• Have watery eyes

• Breathe faster or slower

• Have a faster or slower heartbeat

Developmental Changes in Infantile Spasms

Babies with infantile spasms may experience delayed development, meaning it takes them longer to reach milestones like rolling over or recognizing voices. They may also experience developmental regression, which means they forget how to do things they already learned.

Diagnosing Infantile Spasms

To diagnose infantile spasms, doctors may use an electroencephalography (EEG) to measure your baby's brain activity. Babies with infantile spasms often have an abnormal pattern of electrical activity in their brains called hypsarrhythmia.

Doctors may also use brain scans like computed tomography (CT) or magnetic resonance imaging (MRI) to look for parts of the brain that haven't formed correctly or for lesions or damage to the brain.

Causes of Infantile Spasms

Infantile spasms can be caused by anything that damages the brain, either before or after birth. Some common causes include:

• Tuberous sclerosis complex, an inherited condition that causes noncancerous tumors to grow in the brain and other organs

• Genetic conditions like Down syndrome

• Brain injury

• Problems with brain formation

• Changes in brain structure

• Lack of oxygen to the brain

• Brain infections

• Lesions on the brain

• Bleeding inside the skull

• Inflammation in the brain (encephalitis)

• Metabolism disorders

• Vitamin B deficiency

Sometimes, doctors can't find a cause for infantile spasms, but there's no evidence that it's related to vaccinations or your baby's sex.

If you suspect your baby may have infantile spasms, it's important to talk to your doctor right away. Early diagnosis and treatment can help improve outcomes for babies with this condition.

For more information on infantile spasms, visit the National Institute of Neurological Disorders and Stroke, the Epilepsy Foundation, or the National Organization for Rare Disorders.

The Bottom Line

Early recognition and treatment within the first month of symptom onset dramatically improves developmental outcomes, as delayed treatment often leads to permanent intellectual disability. Parents should seek immediate medical evaluation for any baby showing repetitive flexing movements or developmental regression. If you're concerned about unusual movements or developmental changes in your infant, Doctronic can help connect you with pediatric specialists quickly.