NORD gratefully acknowledges W. Mathern, MD, Professor and Neurosurgical Director, Pediatric Epilepsy Surgery Program, Departments of Neurosurgery and Psychiatry & Biobehavioral Medicine, Mattel Children's Hospital, David Geffen School of Medicine, UCLA; William Davis Gaillard, MD, Professor, Pediatrics and Neurology, George Washington University School of Medicine, Professor Neurology, Georgetown University, Chief, Epilepsy, Neurophysiology, and Critical Care Neurology, Children's National Medical Center, Associate Director, Center for Neuroscience Research, Children's Research Institute; J Helen Cross, The Prince of Wales's Chair of Childhood Epilepsy UCL-Institute of Child Health, Great Ormond Street Hospital for Children & Young Epilepsy and Head of Neurosciences Unit, UCL-Institute of Child Health, London, for assistance in the preparation of this report.
Typically, affected individuals develop focal seizures that may progress to near continuous seizures termed epilepsia partialis continua (EPC). EPC is characterized by a rapid, rhythmic succession of contractions and relaxations of a muscle or muscle group (myoclonus), particularly of the arms, legs, and face, that may occur singularly or in a repetitive, continuous series. In Rasmussen this occurs consistently on one side of the body opposite the side of the inflammation.
Most affected children will exhibit progressive paralysis of one side of the body (hemiparesis) and if the seizures continue developmental disabilities. In many cases, the development of physical and mental abilities of affected children may cease (developmental arrest). In addition, affected children may lose previously acquired physical and mental abilities (developmental regression). Some affected children may exhibit degeneration (atrophy) of one side of the brain and/or progressive confusion, disorientation, and deterioration of intellectual abilities (dementia).
The exact cause of Rasmussen encephalitis is not known. Most researchers now suspect that Rasmussen encephalitis is an autoimmune disorder following review of the tissue involved under the microscope. In autoimmune disorders, the body’s natural defenses (antibodies) fight its own tissue, mistaking it for foreign organisms for no apparent reason.
Some researchers believe that Rasmussen encephalitis may be triggered by an unidentified infection such as influenza, measles, or cytomegalovirus.
Rasmussen encephalitis mostly affects children ten years of age and younger. It is unusual to affect children under two years of age. Adolescents and young adults in much smaller proportions are also affected. There may be a history of some prior mild cold or flu prior to the onset of the seizures. The annual number of new-onset Rasmussen has been estimated as 2.4/10,000,000 persons less than or equal to 18 years of age.
Rasmussen encephalitis may be diagnosed clinically based upon a thorough clinical evaluation, a detailed patient history, and a complete neurological evaluation including advanced techniques such as electroencephalography (EEG), and magnetic resonance imaging (MRI).
During an EEG, the brain’s electrical impulses are recorded. Such studies may reveal brain wave patterns that are characteristic of certain types of epilepsy. During MRI, a magnetic field and radio waves are used to create cross-sectional detailed images of the brain. It is usual that the diagnosis is made after a minimum of two scans which will detail progressive shrinkage of the affected side of the brain.
Treatment of Rasmussen encephalitis is mostly symptomatic and supportive. Special services that may be beneficial to affected children include special social support, physical therapy, and other medical, social, and/or vocational services.
Various anti-seizure medications (anticonvulsants) may be prescribed to treat seizures. However, in most cases, anticonvulsants have proven ineffective. Medical treatments targeted at possible autoimmune disease may be tried, including steroids, immunoglobulin and tacrolimus. Immunological therapies (tacrolimus, intravenous immunoglobulins, potentially others as well) may slow down the neurological and structural deterioration but usually does not improve the epilepsy or progressive brain atrophy. Its precise role in management of Rasmussen encephalitis remains to be determined.
Surgery usually in the form of a cerebral hemispherectomy is the only way to cure the seizures and halt neurodevelopmental regression. However, there is the inevitable resultant functional deficits including hemiparesis (weakness of one side) and hemifield defect (impairment of vision to one side), and where the dominant side of the brain is affected, there may be an effect on language. The difficulty is often deciding on the necessary and best timing of surgery, dependent on the severity of epilepsy and degree of effect on learning and progression of the disease. The decision needs to be made jointly by the family and specialist center who deal with this condition regularly.
The RE Children’s Project (http://www.rechildrens.org) a non-profit non-government organization has established a research consortium among US and international research laboratories to identify the cause of Rasmussen encephalitis and develop new more effective treatments. In order to develop new therapies, this group is soliciting families and patients to volunteer their brain tissue obtained at surgery for research. Contact RE Children’s Project for more information.
Information on current clinical trials is posted on the Internet at www.clinicaltrials.gov. All studies receiving U.S. government funding, and some supported by private industry, are posted on this government web site.
For information about clinical trials being conducted at the NIH Clinical Center in Bethesda, MD, contact the NIH Patient Recruitment Office:
Toll-free: (800) 411-1222
TTY: (866) 411-1010
For information about clinical trials sponsored by private sources, contact:
For information about clinical trials conducted in Europe, contact
Contacts for additional information about Rasmussen encephalitis:
Gary W. Mathern, MD
The Davies endowed Chair for Epilepsy Research at UCLA
Professor and Neurosurgical Director, Pediatric Epilepsy Surgery Program
Departments of Neurosurgery and Psychiatry & Biobehavioral Medicine
Mattel Children’s Hospital
David Geffen School of Medicine
University of California, Los Angeles
William Davis Gaillard, MD
Professor, Pediatrics and Neurology
George Washington University School of Medicine
Chief, Epilepsy, Neurophysiology, and Critical Care Neurology
Children’s National Medical Center
Associate Director, Center for Neuroscience Research
Children’s Research Institute
J. Helen Cross
The Prince of Wales’s Chair of Childhood Epilepsy UCL-Institute of Child Health, Great Ormond Street Hospital for Children & Young Epilepsy
Head of Neurosciences Unit
UCL-Institute of Child Health
4/5 Long Yard
London WC1N 3LU
Telephone number: 0207 599 4105
Fax Number: 0207 430 0032
PA Anne Brown: firstname.lastname@example.org
The Neville Epilepsy Centre
St Piers Lane
Surrey RH7 6PW
PA: Louise Jones: email@example.com
Tel: 01342 831212
Bien CG et al., Rasmussen encephalitis: Incidence and course under randoized therapy with tacrolimus or intravenous immunoglobulins, Epilepsia. in press.
Kruse, C. A., Pardo, C. A., Hartman, A. L., Jallo, G., Vining, E. P. G., Voros, J., Gaillard, W. D., Liu, J., Oluigbo, C., Malone, S., Bleasel, A. F., Dexter, M., Micati, A., Velasco, T. R., Machado, H. R., Martino, A. M., Huang, A., Wheatley, B. M., Grant, G. A., Granata, T., Freri, E., Garbelli, R., Koh, S., Nordli, D. R., Campos, A. R., O’Neill, B., Handler, M. H., Chapman, K. E., Wilfong, A. A., Curry, D. J., Yaun, A., Madsen, J. R., Smyth, M. D., Mercer, D., Bingaman, W., Harvey, A. S., Leventer, R. J., Lockhart, P. J., Gillies, G., Pope, K., Giller, C. A., Park, Y. D., Rojiani, A. M., Sharma, S. J., Jenkins, P., Tung, S., Huynh, M. N., Chirwa, T. W., Cepeda, C., Levine, M. S., Chang, J. W., Owens, G. C., Vinters, H. V. and Mathern, G. W. Rasmussen encephalitis tissue transfer program. Epilepsia. 2016; 57:1005–1007. doi: 10.1111/epi.13383
Varadkar S, Bien CG, Kruse CA, Jensen F, Bauer J, Pardo CA, Vincent A, Mathern GW, and Cross HJ. Rasmussen’s encephalitis: present understanding and treatment advances. The Lancet-Neurology, 2014;13:195-205. PMID: 24457189
Owens GC, Huynh M, Chang JW, McArthur D, Hickey MJ, Vinters HV, Mathern GW, and Kruse CA. Differential expression of interferon-γ and chemokine genes distinguishes Rasmussen encephalitis from cortical dysplasia and indicates an early Th1 response. Journal of Neuroinflammation, 2013;May 2;10:56. doi: 10.1186/1742-2094-10-56. PMID: 23639073.
Bauer J, Vezzani A, Bien CG. Epileptic encephalitis: the role of the innate and adaptive immune system. Brain Pathology. 2012:22(3):412-21.
Bien CG, Granata t, Antozzi C, et al. Pathogenesis, diagnosis and treatment of Rasmussen encephalitis: a European consensus statement. Brain. 2005:128, 454-71.
Koh S. Mathern GW, Glasser g, et al. Status ellipticus and frequent seizures: incidence and clinical characteristics in pediatric epilepsy surgery patients. Epilepsia. 2005;46:1950-54.
Korkman M, Granstrom ML, Kantola-Sorsa E, et al. Two-year follow-up of intelligence after pediatric epilepsy surgery. Pediatr Neurol. 2005;33:173-78.
Gaynor Y, Freilinger M, Dulac O, Levite M. Monozygotic twins discordant for epilepsy differ in the levels of pathogenic antibodies and cytokines. Autoimmunity.2005;38:139-50.
Freeman JM. Rasmussen’s syndrome: progressive autoimmune multi-focal encephalopathy. Pediatr Neurol. 2005;32:295-99.
Tubbs RS, Nimjee SM, Oakes WJ. Long-term follow-up in children with functional hemispherectomy for Rasmussen’s encephalitis.Childs Nerv Syst. 2005;21:461-65.
Hart Y. Rasmussen’s encephalitis. Epileptic Disord. 2004;6:133-44.
NINDS Rasmussen’s Encephalitis Information Page. National Institute of Neurological Disorders and Strokes. National Institutes of Health. www.ninds.nih.gov/disorders/rasmussen/rasmussen.htm. Last Updated December 19, 2011. Accessed June 21, 2016.
Rasmussen’s Encephalitis. The Hemispherectomy Foundation. http://hemifoundation.intuitwebsites.com/rasmussen.html. Accessed June 21, 2016.
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