The effective treatment of West syndrome still poses a great challenge in pediatric neurology. In the overall long term view, the majority of patients with the syndrome suffer a poor outcome due to chronic epilepsy, mental retardation, and other neurodevelopmental shortcomings.
However, the prognosis for a case is greatly dependent on the underlying etiology of the seizures. Therefore, each case of symptomatic, cryptogenic and idiopathic West syndrome must be considered on an individual basis. For example, while 28-50% of infants with idiopathic West syndrome will have normal or near-normal cognitive development, for those suffering from symptomatic West syndrome this value is only 14%.
Clinical spasms very rarely persist in adulthood; these and the typical EEG pattern spontaneously disappear by 3 to 4 years of age but up to 50-70% of children diagnosed with infantile spasms develop other types of seizures. In addition to this, mental retardation (usually of a profound nature) also occurs in 70-90% of patients in the future, accompanied by psychiatric problems. Even though epileptic spasms usually reduce in number by mid-childhood, 18-50% of children will develop Lennox-Gastaut syndrome or some other form of symptomatic generalized epilepsy.
However, early detection and prompt administration of effective treatment have been shown to improve the resultant neurodevelopmental outcomes (such as severe-to-profound retardation). Currently, approximately half of all children with the syndrome become entirely free of the attacks with the aid of medication but this would be an even higher value if the optimal regimen for treatment was known.
Early pharmacological action would be particularly beneficial for idiopathic cases where, in general, children have the most promising prognosis. In fact, 28-50% of children with idiopathic West syndrome have normal or borderline-normal cognitive development following diagnosis compared with only 14% of children with symptomatic West syndrome.
In addition to underlying etiology, treatment is also known to influence the outcome a patient faces. For example, a good prognosis might be expected if the age at onset is older than 4 months, if there is an absence of EEG abnormalities, if the spasms are of a short duration or if there is a rapid response to treatment (less than a month) and without recurrence. Therefore, regardless of what the underlying cause is, the aim of treatment is to achieve control of the seizures as soon as possible, particularly if there is a hope for normal intellectual development.
For an unknown reason, West syndrome occurs in 1- 5% of children with Down's syndrome and these may also have a more positive prognosis. They are less likely to develop Lennox-Gastaut syndrome or other forms of epilepsy. On the other hand, if their seizures are difficult to control, the child is at risk of developing an autistic spectrum disorder.
West syndrome is generally not life-threatening but it occurs more often in children with life-threatening conditions. Furthermore, the treatments used for West syndrome can (rarely) cause death. Due to this, only 5 out of every 100 children diagnosed with West syndrome do not survive beyond the age of five years.