Long-term follow-up of a patient with subacute sclerosing panencephalitis successfully treated with intrathecal interferon alpha

To clarify long-term effects of intrathecal administration of interferon (IFN)-α in subacute sclerosing panencephalitis (SSPE), we followed up a patient with SSPE for 18 years, who had been treated successfully using intrathecal IFN-α with response-based dose adjustments. IFN-α therapy dramatically induced remission of disease and greatly improved quality of life for 7–8 years, but this was followed by severely deterioration with decorticate posturing and akinetic mutism. Thus, IFN-α-induced remission appears most likely to be temporary, even when an SSPE patient shows an excellent initial response. To improve long-term outcome for SSPE patients, more effective therapy is needed.