Infantile Spasm Syndrome (West Syndrome) is responsible for almost 25% of epilepsies with onset in the first year of life. The condition is typified by the triad of infantile spasms, abnormal and chaotic brain wave patterns, called hypsarrythmia, and mental retardation. The onset of ISSX is generally within the first year of life. The characteristic spasms begin immediately after sleep arousal, and are typically symmetrical, bilateral, brief, and sudden contractions of the axial muscle groups. Although these spasms usually stop by the age of five years, other, more severe seizure types may take over in over half of the affected patients. Worldwide, about 20 in every 100,000 children born are affected by this condition.
CT and MRI scans are used to diagnose this condition in children with spasms. Differentials to be considered include exaggerated startle responses, benign myoclonus of early infancy, myoclonic ecstatic epilepsy, and Sandifer syndrome. Earlier forms of treatment used to focus on corticosteroids such as ACTH and prednisolone. However, newer anticonvulsants, such as GABAergic drugs, have shown more efficiency. Surgery may be required if lesions are noticed on the brain. Since the condition is associated with mental retardation and learning disabilities, occupational, speech, and physio-therapy are also required. The prognosis for children with ISSX is poor, despite treatment. Only about 12% of the affected patients progress to normal mental and motor development. Delay in treatment results in worse outcomes.