A case of Rasmussen encephalitis treated with rituximab.

BACKGROUND: A 20-year-old woman was referred to our intensive care unit with a high frequency (every 1-2 min) of focal motor seizures. She had been diagnosed as having biopsy-proven Rasmussen encephalitis (RE) of the right hemisphere 7 years previously, since when she had been treated with numerous antiepileptic drugs, as well as with continuous immunotherapies, such as tacrolimus, corticosteroids, mycophenolate mofetil, intravenous immunoglobulin and immunoadsorption. Although hemispherectomy had been avoided due to slow progression of RE, she had not been seizure-free for more than 7 weeks since diagnosis.

INVESTIGATIONS: EEG and MRI.

DIAGNOSIS: Focal motor status epilepticus associated with right hemispheric RE, causing continuous epileptic activity and unilateral atrophy with edema in the right hemisphere.

MANAGEMENT: Immunoadsorption was used initially to treat the seizures. Once they had ceased, we used 375 mg/m2 intravenous rituximab--a monoclonal anti-CD20 antibody--once-weekly for 4 weeks to stabilize the condition, leading to complete depletion of CD19+ B cells. Rituximab infusions were used again when concentrations of CD19+ B cells rose and focal seizures re-emerged. The patient remained on antiepileptic therapy (levetiracetam, oxcarbazepine, zonisamide and phenobarbital) throughout treatment.