Background: Steroids (hydrocortisone or ACTH) still remain the usual treatment for infantile spasms (IS). However, since 1990, some authors have reported the efficacy of vigabatrin (VGB), especially in cases related to tuberous sclerosis.
Population and methods: Seventy children with infantile spasms were treated by VGB first line monotherapy. Modalities of treatment and monitoring were the same for all children. VGB was given at the daily dose of 100 mg/kg during 1 week. If spasms persisted, the daily VGB dose was increased to 150 mg/kg during a 2nd week. In case of persistence of IS, on the 15th day, hydrocortisone was then added to VGB. Of the 70 infants, 39 were symptomatic and 31 cryptogenic.
Results: On VGB, 37 children (54%) stopped having IS within a mean 3.5 days. Response to VGB was different according to etiology. Among cryptogenic cases, 22 infants (71%) definitively stopped having spasms and only one relapsed. Among symptomatic cases, only 15 infants (38%) stopped having IS, and half (8/15) relapsed. VGB mean daily dose at cessation of spasms was 114 mg/kg. Side effects were transient drowsiness (27%) and agitation (12%). Mean follow-up was 10 months (1-24 months). Seventy-five percent of the infants presenting with a focus of spike after the 1st month of treatment relapsed.
Conclusion: Infants with cryptogenic spasms have a good response to VGB monotherapy. When mental retardation is noticed before IS, and MRI is normal, there is no efficacy. In these cases, the best treatment seems to be prolonged corticotherapy associated with VGB.