The seizures are characterized by sudden, typically bilateral, spasms of the neck, trunk, and/or extremities with associated brief loss of consciousness. Spasms can be flexor, extensor, or mixed. Most seizures last seconds and occur in clusters with up to hundreds of spasms in a day.
Infantile spasms can be associated with many neurologic conditions including tuberous sclerosis, neuronal migration disorders, hypoxic-ischemic injury, cerebral palsy, or Down syndrome. Up to one-third of cases have no obvious underlying abnormality. Prognosis is typically poor (although somewhat better in the cryptogenic group); while spasms usually remit by age 3, most children go on to develop other seizure types, with up to 50% developing Lennox-Gastaut syndrome. Developmental delay and cognitive impairment is common.
G40.822 – Epileptic spasms, not intractable, without status epilepticus
28055006 – West syndrome
Differential Diagnosis & Pitfalls