Abstracts

Rationale: Inflammation and immune mediated mechanisms are hypothesized to play a role in epileptogenesis. In the face of medically refractory epilepsy, IVIG and corticosteroids have been used as alternatives to conventional anti-epileptic medications in the hope of abrogating the underlying mechanism leading to the cycle of frequent refractory seizures. In this study, we present our experience treating medically refractory epileptic children with either IVIG or corticosteroids and the differences in the respective outcomes.Methods: A systematic and retrospective chart review was performed on all children with medically refractory epilepsy who were treated with either prednisone (2mg/Kg/day for 2 weeks followed by a 6 week taper) or IVIG (1g/Kg/month for 6 months) between 2008-2015. Children with infantile spasms and evidence of a primary autoimmune mediated epilepsy were excluded. Factors studied include: epilepsy type and etiology, developmental outcome, seizure treatment outcome, timing of the best seizure treatment outcome, timing of relapse of seizures, and adverse effects.Results: Twenty-five patients met the inclusion criteria: 12 patients received IVIG, and 13 patients received prednisone. Of the patients receiving IVIG and prednisone, 6 patients and 2 patients, respectively, had focal epilepsy. Etiologies include genetic causes (6 in IVIG and 8 in prednisone), lesional (IVIG (2), prednisone (2)), and cryptogenic (IVIG (4), prednisone (3)). All patients in IVIG group (100%) and 11/13 (85%) patients treated with prednisone were neurodevelopmentally delayed with evidence of epileptic encephalopathy. Of the children treated with IVIG, seizure frequency improved in 7/12 (58%) patients with 4 patients had a greater than 90% seizure reduction. Mean time to best response with IVIG was 2.8 months (range 1-6 months) after initial infusion. Of the responders, 5 children had seizure relapse at 3-4 weeks following the previous infusion. Only 2 children continued to have their best seizure outcome greater than 1 month following the last infusion. Of the children treated with prednisone, 4/13 (31%) patients responded and all became seizure free. Mean time to best response was between 3-4 weeks following the initial treatment. In 3 of these patients, seizure freedom was maintained with continued anti-epileptic medication for periods of at least 12 months. During treatment, 5 children became cushinoid and 3 had significantly worsened behaviour.Conclusions: Both IVIG and high dosage prednisone are viable options in treating medically refractory epilepsy in children. In this study, more of the IVIG treated responded; however, the response was more graded as opposed to the all or none response pattern seen in the prednisone group. In addition, children treated with prednisone responded within 4 weeks of initiation as opposed to a mean delay of 2.8 months with IVIG. Expectedly, major adverse effects occurred in the prednisone treated children thus limiting its repeated use