From the Guidelines
Infantile spasms (IS), also known as West syndrome, are a rare and serious type of seizure disorder that typically begins in the first year of life, characterized by sudden, brief stiffening or jerking movements, often associated with developmental regression and a characteristic EEG pattern called hypsarrhythmia. These seizures often occur in clusters, with the baby's head bending forward while arms and legs extend outward, sometimes referred to as "jackknife" or "salaam" seizures 1. According to the most recent guidelines, first-line treatment typically includes ACTH (adrenocorticotropic hormone) or vigabatrin (Sabril), with oral prednisolone as an alternative steroid option 1.
Key Characteristics of Infantile Spasms
- Sudden, brief stiffening or jerking movements
- Often occur in clusters
- Associated with developmental regression
- Characteristic EEG pattern called hypsarrhythmia
- Typically begins in the first year of life, usually between 4-8 months of age
Treatment and Management
- First-line treatment: ACTH (adrenocorticotropic hormone) or vigabatrin (Sabril)
- Alternative steroid option: oral prednisolone
- Treatment should begin immediately upon diagnosis to prevent delays that can worsen developmental outcomes
- Regular follow-up with a pediatric neurologist is essential to monitor treatment response and developmental progress
Underlying Causes and Risks
- Brain malformations
- Genetic disorders
- Metabolic conditions
- Brain injuries
- Risk of permanent cognitive impairment if left untreated
- Parents should be advised to record any suspicious movements on video to help with diagnosis, as noted in the guidelines for managing cardio-facio-cutaneous syndrome, which may be associated with infantile spasms 1.
From the Research
Definition and Characteristics of Infantile Spasms
- Infantile spasms, also known as West syndrome, is a rare form of epilepsy that begins during early infancy 2, 3, 4, 5, 6.
- It is characterized by brief, symmetrical contractions of the musculature of the neck, trunk, and extremities 4.
- Infantile spasms often occur with a concomitant hypsarrhythmia on electroencephalogram (EEG) and developmental regression, which is known as West Syndrome 4.
Epidemiology and Prognosis
- The estimated prevalence of infantile spasms is 1 in 2000 - 6000 live births 3.
- The peak incidence of infantile spasms is between 4 - 7 months of age 3.
- The majority of patients with infantile spasms have a poor prognosis with intractable epilepsy, severe developmental delays, and/or significant cognitive impairments 3.
- Approximately 70 - 90% of patients with infantile spasms have mental retardation, and 20 - 50% develop Lennox-Gastaut syndrome 3.
Treatment Options
- Adrenocorticotropic hormone (ACTH), corticosteroids, and vigabatrin are commonly used as first-line treatments for infantile spasms 2, 3, 4, 5, 6.
- Other treatment options include valproic acid, topiramate, zonisamide, levetiracetam, and the ketogenic diet 2, 3, 5, 6.
- Surgical resection may be considered for patients with focal cortical dysplasia and intractable infantile spasms 3, 6.