Improvement in adult-onset Rasmussen's encephalitis with long-term immunomodulatory therapy.

OBJECTIVE

To study the immediate and chronic effects of high-dose, long-term human i.v. immunoglobulin (h i.v.Ig) therapy in two patients with advanced adult-onset Rasmussen's encephalitis (RE).

BACKGROUND

Despite advances in our understanding of the autoimmune pathogenesis of RE, medical options for chronic treatment are limited.

METHODS

In an open-label treatment trial, treatment started with monthly cycles of high-dose h i.v.Ig (0.4 g/kg/d for 5 days) followed by maintenance therapy (0.4 g/kg 1 day each month) after the patients' conditions began to improve. Outcome measures included clinical, psychological, functional, and laboratory assessments before and at relevant intervals throughout 1 year of treatment.

RESULTS

In both patients, unrelenting pretreatment deterioration halted, and after this they displayed striking improvements in seizure control, hemiparesis, and cognition that produced useful recovery of function. Improvements were delayed until after 2 to 4 monthly cycles of high-dose h i.v.Ig and continued when patients switched to maintenance treatment. Their recoveries were accompanied by increased cerebral perfusion on interictal SPECT and suppression of inflammatory markers in CSF.

CONCLUSIONS

h i.v.Ig can be a useful, possibly disease-modifying, long-term therapy for adult-onset RE that should be considered before radical surgery is performed. Because improvements can be delayed, we propose guidelines for intensive and prolonged trials of immunomodulatory therapy in adults with this syndrome.