Abstracts

Rationale: Rasmussen s encephalitis (RE) is a rare but severe immune mediated brain disorder leading to unilateral hemispheric atrophy, associated progressive neurological dysfunction and intractable epilepsy. At present there is no conclusive evidence as to why and how RE starts. At our institution 6 patients with RE were diagnosed and treated between 2006 and 2011. Treatment decisions were based on the age of the child at seizure intractability and development of neurologic deficits during disease progression. Methods: Retrospective chart review of pediatric patients with RE at our institution. Information sought included age at first seizure onset, age at diagnosis of RE, seizure types and frequency, age at onset of hemiparesis, EEG and imaging results, and treatment received. Diagnosis of RE was based on published standards. Treatments used included antiepileptic medications (AEDs), steroids, intravenous immunoglobulin (IVIG) and surgery (hemispherotomy/focal resection). Outcome measures were seizure freedom, AED withdrawal, degree of cognitive impairment and presence of hemiparesis.Results: Six patients identified with mean age of seizure onset 5.8 years (range 3-11 years) and mean age at diagnosis of RE 26.3 months (range 2-60 months). 4 patients presented with epilepsia partialis continua (EPC), 1 patient with non convulsive status epilepticus (NCS) and 1 patient with complex partial seizures (CPS) and dystonia. 2/4 patients responded to steroids with resolution of EPC/NCS. Both had edema on MRI of the brain. One had recurrent NCS and re challenge with steroids was not effective after edema resolved. 2/6 patients responded to IVIG with resolution of EPC. 1/6 patients received Tacrolimus without success. 1 patient with NCS had temporal lobectomy but seizures returned and pathology showed RE. 2/6 patients had hemispherotomy and are seizure free and off AEDs. 1/4 patients with medical management is seizure free but all are on AEDs. All patients had normal development prior to onset of RE. 5/6 patients now require special education services. Both patients with hemispherotomies had hemiparesis prior to surgery. 2 of the remaining 4 patients also are hemiparetic. Conclusions: Steroids were effective in treating EPC or NCS when edema was present on MRI of the brain. IVIG stabilized course in 2/4 patients with RE but seizures and cognitive impairment persisted. Hemispherotomy provided long term seizure freedom. Optimal therapy depends on the age, course and associated disability. In our series hemispherotomy provided the best chance of long term seizure freedom.