Rasmussen's encephalitis occurs most often in children under the age of 10, but may also occur in adolescents and adults. It is estimated to occur in 1 in 500,000 to 1,000,000 individuals.
Symptoms
Symptoms of Rasmussen's encephalitis may include:- frequent and severe seizures
- loss of motor skills and speech
- paralysis on one side of the body (called hemiparesis)
- cognitive problems
- loss of vision on one side
Diagnosis
Diagnosis of Rasmussen's encephalitis can be difficult, since other nervous system disorders, including other types of encephalitis, can produce similar symptoms. Tests will be done to exclude other diseases and help confirm the diagnosis. Magnetic resonance imaging (MRI) of the brain can help uncover brain abnormalities. Blood tests may be done to look for antibodies and exclude infections. A sample of brain tissue (brain biopsy) may be taken and examined to help confirm the inflammation present in Rasmussen's encephalitis.Treatment
Anti-seizure medications often do not control the seizures present in Rasmussen's encephalitis. Studies have shown some success with treatments that reduce the autoimmune response, such as medications that suppress the immune system.Surgery may be used to control seizures and remove diseased brain tissue in individuals who are disabled by Rasmussen's encephalitis. This may mean surgical removal of large areas, or sometimes all, of a hemisphere of the brain (called hemispherectomy). In children, the remaining hemisphere may partially compensate for the lost brain tissue, but some paralysis, cognitive problems, and speech problems usually remain.
It is hoped that in the future, as researchers learn more about the best use of immune therapy in Rasmussen's encephalitis, fewer affected individuals will need brain surgery.
Sources:
"Rasmussen's Encephalitis." Encephalitis. 25 Mar 2008. Encephalitis Society. 6 Dec 2008.
"NINDS Rasmussen's Encephalitis Information Page." Disorders. 7 Feb 2008. National Institute for Neurological Disorders and Stroke. 6 Dec 2008.
