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Anti-NMDA (N-methyl D-aspartate) receptor antibody encephalitis, also termed NMDA receptor antibody encephalitis, is an acute form of encephalitis which is potentially lethal but has high probability for recovery. It is caused by an autoimmune reaction primarily against the NR1 subunit of the NMDA receptor. Different descriptions and syndromal designations for this disease existed in medical literature prior to 2007 but it was then that the disease was officially categorized and named by Dr. Josep Dalmau and colleagues. Movement disorder relapses after herpes simplex virus 1 (HSV1) encephalitis have been hypothesized to be secondary to postviral autoimmunity. Recently, a proportion of patients with HSV1 encephalitis (HSE) were shown to produce autoantibodies against N-methyl-D-aspartate receptor (NMDAR). The condition is associated with tumours, mostly teratomas of the ovaries, and thus can be considered a paraneoplastic syndrome. However, there are a substantial number of cases with no detectable tumour and in fact it is emerging that most cases do not have tumour. ==Signs and symptoms== Prior to the development of a symptom complex that is specific to anti-NMDA receptor encephalitis, patients may experience prodromal symptoms. These could include headaches, flu-like illness, or symptoms similar to an upper respiratory infection. These symptoms may be present for weeks or months prior to disease onset.〔 Beyond the prodromal symptoms the disease progresses at varying rates and patients may present with a variety of neurologic symptoms. During the initial stage of the disease symptoms vary slightly between children and adults. However, behavior changes are a common first symptom within both groups. These changes often include increased agitation, paranoia, psychosis, and violent behaviors. Other common first manifestations include seizures and bizarre movements mostly of the lips and mouth but also including pedaling motions with legs or hand movements resembling playing a piano. Some other symptoms typical during the disease onset include impaired cognition, memory deficits, and speech problems (including aphasia or mutism).〔 The symptoms usually show as psychiatric in nature, which may confound the differential diagnosis. In many cases, this leads to the illness going unnoticed. As the disease progresses the symptoms become medically urgent and often include autonomic dysfunction, hypoventilation, cerebellar ataxia, hemiparesis, loss of consciousness, or catatonia. During this acute phase, most patients require care in an intensive care unit to stabilize breathing, heart rate, and blood pressure. Loss of feeling in one side of the body can be a symptom.〔Cahalan, Susannah. Brain on Fire-My Month of Madness, New York: Simon & Schuster, 2013.〕 One distinguishing characteristic of anti-NMDA receptor encephalitis is the concurrent presence of many of the above listed symptoms. The majority of patients experience at least four symptoms with many experiencing six or seven over the course of the disease.〔〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Anti-NMDA receptor encephalitis」の詳細全文を読む スポンサード リンク
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