Objective: Rasmussen's chronic encephalitis, a cause of intractable epilepsy in childhood, is described in three adults.
Setting: Inpatient epilepsy unit.
Patients: Of 11 patients with pathological confirmation of Rasmussen's encephalitis, three were adults with intractable seizures, progressive sensorimotor deficits, and cognitive decline beginning at the ages of 36, 24, and 16 years.
Results: Clinical, electroencephalographic, and magnetic resonance imaging findings indicated patchy, multifocal involvement of primarily one hemisphere, but the adults had more evidence of disease in the opposite hemisphere than occurs in children. The sensorimotor deficit that the adults developed was greater and the cognitive decline was less than in children. Seizure control following multilobe resection was proportionate to the amount of tissue removed. Cytomegalovirus genome was found in the resected cortical tissue of all three patients.
Conclusions: Rasmussen's encephalitis is a cause of intractable epilepsy with progressive neurological deficit in adults as well as children. Cytomegalovirus may be involved in the pathogenesis of the disease.