West Syndrome: Questions Aplenty- Few Answers

Excerpt

West syndrome is an infantile-onset epileptic encephalopathy, characterized by epileptic spasms, developmental delay or regression, and hypsarrythmia on the EEG [1]. Though it can result from genetic or metabolic causes, a structural etiology is most commonly identified in Indian children [2]. In addition to the epileptic spasms, affected children are at high risk for developmental disabilities, intellectual and behavioral abnormalities, and long-term epilepsy. Epileptic spasms are unique in that they are resistant to most conventional antiepileptic drugs and hormonal therapy with corticosteroids has proven to be the most effective treatment. The mechanism of action of corticosteroids on epileptic spasms is still unclear, but it is believed that it is due to inhibition of Corticotropin-releasing hormone (CRH) overexpression in these children. Though high-dose Adrenocorticotropic hormone (ACTH) had been the standard of treatment, based on limited evidence, international guidelines suggest low-dose ACTH could be used as an alternative to the standard high-dose therapy [3]. The role of the other antiepileptic drugs has at best been unclear except for Vigabatrin. Vigabatrin has been shown to be effective in spasm-control in infants with Tuberous sclerosis (TS) and is considered the drug of choice in these patients. Although Vigabatrin is also efficacious in children with West syndrome resulting from other etiologies, the equivalence of Vigabatrin to corticosteroids in non-TS patients has not been proven [4]. Most trials addressing the use of corticosteroids in treatment of epileptic spasms have involved a small number of participants, studied heterogenous populations, compared varying doses of one treatment with another and used various end-points to measure the success of treatment, making clear recommendations difficult [5]. Furthermore, ACTH therapy has its own set of challenges, the most important of which is the high incidence of adverse effects, requirement of daily injections, and the high cost of treatment. ACTH use in developing countries is further complicated by poor parental literacy and awareness; lack of availability of physicians to administer and monitor therapy; and requirement for refrigeration. The problem is further compounded by non-availability of Vigabatrin in the Indian market. The use of dietary therapies, though encouraging [6], is also fraught with difficulties in resource limited settings. In such a context, oral prednisolone is an attractive option but there is a lack of good quality evidence to support its efficacy. …