West Syndrome: Rare form of infantile spasm that manifests during
the first months of life and is characterized by hypsarrhythmia (abnormal
brain waves) and mental retardation. There are two forms: cryptogenic, which has no
known cause, and symptomatic, which results from an underlying condition or factor. The
cryptogenic form usually follows a normal pregnancy, birth, and development
and is associated with a more favorable outcome. Patients affected with the
symptomatic form often develop mental retardation. Clinical features include
involuntary muscle spasms occurring during seizures, typically beginning
suddenly and lasting a few seconds. They may occur during sleep or upon
awakening, are characterized by sudden, involuntary contractions of the
head, neck, and trunk, with uncontrolled extension of the legs and arms. The
syndrome often develops into the Lennox-Gastaut form of epilepsy with
seizures that are difficult to control, making early diagnosis very
important.