Infantile spasms (IS) is a rare type of epilepsy that occurs in infancy and childhood. When the triad of symptoms including epileptic spasms, developmental delays, and a specific brain wave pattern (called hypsarrhythmia) on electroencephalography (EEG) are present, the condition is sometimes referred to as “West Syndrome”. The onset of IS usually occurs in the first year of life and is typically seen between 4 to 8 months of age.
Once the spasms begin, other changes may be observed, such as not meeting developmental milestones, decreased social interactions, and increased fussiness. Infantile spasms typically end by age 5; however, they may be replaced with another seizure type. There are many causes associated with IS, such as birth injury, metabolic disorders, and genetic disorders; however, the cause in some babies may be unknown.