Rasmussen's encephalitis

Overview
Rasmussen's encephalitis, also Chronic Focal Encephalitis (CFE), is a rare, progressive neurological disorder, characterized by frequent and severe seizures, loss of motor skills and speech, hemiparesis (paralysis on one side of the body), encephalitis (inflammation of the brain), dementia, and mental deterioration. The disorder, which affects a single cerebral hemisphere, generally occurs in children under the age of 10.

Treatment
When seizures have not spontaneously remitted by the time hemiplegia and aphasia are complete, the standard treatment for Rasmussen's encephalitis is surgery to remove or disconnect the affected part of the brain (hemispherectomy). Although anti-epileptic drugs may be prescribed initially, they are usually not effective in controlling the seizures. Alternative treatments may include plasmapheresis (the removal and reinfusion of blood plasma), intravenous immunoglobulin,ketogenic diet (high fat, low carbohydrate), and steroids.

Associated conditions
Rasmussen's encephalitis has been recorded with a neurovisceral porphyria, acute intermittent porphyria. Drug resistant/drug refractory seizures, Lennox-Gastaut syndrome require deeper investigations for neurovisceral porphyrias including acute intermittent porphyria, hereditary coproporphyria and variegate porphyria. Multiple anti-seizure drugs are porphyrinogenic and should be avoided if these genetic disorders are present. Diagnosis may be difficult in children who require enzyme or DNA testing for these disorders.

Prognosis
Prognosis for individuals with Rasmussen's encephalitis varies. Untreated, the disorder may lead to severe neurological deficits including mental retardation and paralysis. In some patients surgery decreases seizures. However, most patients are left with some paralysis and speech deficits.

Eponym
It is named for Theodore Rasmussen.

Genetics
In the 1990s, there was some evidence tying Rasmussen's encephalitis to GRIA3 (GluR3), but more recent studies have been inconclusive.